National Library of Energy BETA

Sample records for atmospheric optics sb

  1. Atmospheric optical calibration system

    DOE Patents [OSTI]

    Hulstrom, Roland L. (Bloomfield, CO); Cannon, Theodore W. (Golden, CO)

    1988-01-01

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

  2. Atmospheric optical calibration system

    DOE Patents [OSTI]

    Hulstrom, R.L.; Cannon, T.W.

    1988-10-25

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

  3. The formation mechanisms and optical characteristics of GaSb quantum rings

    SciTech Connect (OSTI)

    Lin, Wei-Hsun; Pao, Chun-Wei [Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China)] [Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Wang, Kai-Wei [College of Photonics, National Chiao-Tung University, Tainan 711, Taiwan (China)] [College of Photonics, National Chiao-Tung University, Tainan 711, Taiwan (China); Liao, Yu-An [Department of Electrophysics, National Chiao-Tung University, Hsinchu 300, Taiwan (China)] [Department of Electrophysics, National Chiao-Tung University, Hsinchu 300, Taiwan (China); Lin, Shih-Yen [Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China) [Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Department of Photonics, National Chiao-Tung University, Hsinchu 300, Taiwan (China); Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2013-08-07

    The growth mechanisms and optical characteristics of GaSb quantum rings (QRs) are investigated. Although As-for-Sb exchange is the mechanism responsible for the dot-to-ring transition, significant height difference between GaSb quantum dots (QDs) and QRs in a dot/ring mixture sample suggests that the dot-to-ring transition is not a spontaneous procedure. Instead, it is a rapid transition procedure as long as it initiates. A model is established to explain this phenomenon. Larger ring inner diameters and heights of the sample with longer post Sb soaking time suggest that As-for-Sb exchange takes places in both vertical and lateral directions. The decreasing ring densities, enlarged ring inner/outer diameters and eventually flat GaSb surfaces observed with increasing growth temperatures are resulted from enhanced adatom migration and As-for-Sb exchange with increasing growth temperatures.

  4. Effect of arsenic on the optical properties of GaSb-based type II quantum wells with quaternary GaInAsSb layers

    SciTech Connect (OSTI)

    Janiak, F. Motyka, M.; S?k, G.; Dyksik, M.; Ryczko, K.; Misiewicz, J.; Weih, R.; Höfling, S.; Kamp, M.; Patriarche, G.

    2013-12-14

    Optical properties of molecular beam epitaxially grown type II “W” shaped GaSb/AlSb/InAs/GaIn(As)Sb/InAs/AlSb/GaSb quantum wells (QWs) designed for the active region of interband cascade lasers have been investigated. Temperature dependence of Fourier-transformed photoluminescence and photoreflectance was employed to probe the effects of addition of arsenic into the original ternary valence band well of GaInSb. It is revealed that adding arsenic provides an additional degree of freedom in terms of band alignment and strain tailoring and allows enhancing the oscillator strength of the active type II transition. On the other hand, however, arsenic incorporation apparently also affects the structural and optical material quality via generating carrier trapping states at the interfaces, which can deteriorate the radiative efficiency. These have been evidenced in several spectroscopic features and are also confirmed by cross-sectional transmission electron microscopy images. While arsenic incorporation into type II QWs is a powerful heterostructure engineering tool for optoelectronic devices, a compromise has to be found between ideal band structure properties and high quality morphological properties.

  5. Self-Assembled ErSb Nanostructures with Optical Applications...

    Office of Scientific and Technical Information (OSTI)

    electrodes - solar, defects, charge transport, materials and chemistry by design, optics, synthesis (novel materials), synthesis (self-assembly), synthesis (scalable...

  6. Time resolved magneto-optical studies of ferromagnetic InMnSb films

    SciTech Connect (OSTI)

    Frazier, M.; Kini, R. N.; Nontapot, K.; Khodaparast, G. A. [Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States); Wojtowicz, T. [Institute of Physics, Polish Academy of Sciences 02-668 Warsaw (Poland); Liu, X.; Furdyna, J. K. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2008-02-11

    We report time resolved magneto-optical measurements in InMnSb ferromagnetic films with 2% and 2.8% Mn contents grown by low temperature molecular beam epitaxy. In order to probe a possible interaction between the spins of photoexcited carriers and the Mn ions, we measured spin dynamics before and after aligning the Mn ions by applying an external magnetic field at temperatures above and below the samples' Curie temperatures. We observed no significant temperature or magnetic field dependence in the relaxation times and attribute the observed dynamics entirely to the relaxation of photoexcited electrons in the conduction band where the s-d coupling with the localized Mn ions is significantly weaker compared to the p-d exchange coupling. We observed several differences in the optical response of our InMnSb samples which could have been influenced mainly by the samples' growth conditions.

  7. Optical Intensity Interferometry through Atmospheric Turbulence

    E-Print Network [OSTI]

    Peng Kian Tan; Aik Hui Chan; Christian Kurtsiefer

    2015-12-29

    Conventional ground-based astronomical observations suffer from image distortion due to atmospheric turbulence. This can be minimized by choosing suitable geographic locations or adaptive optical techniques, and avoided altogether by using orbital platforms outside the atmosphere. One of the promises of optical intensity interferometry is its independence from atmospherically induced phase fluctuations. By performing narrowband spectral filtering on sunlight and conducting temporal intensity interferometry using actively quenched avalanche photon detectors (APDs), the Solar $g^{(2)}(\\tau)$ signature was directly measured. We observe an averaged photon bunching signal of $g^{(2)}(\\tau) = 1.693 \\pm 0.003$ from the Sun, consistently throughout the day despite fluctuating weather conditions, cloud cover and elevation angle. This demonstrates the robustness of the intensity interferometry technique against atmospheric turbulence and opto-mechanical instabilities, and the feasibility to implement measurement schemes with both large baselines and long integration times.

  8. Optical reflection from the Bragg lattice of AsSb metal nanoinclusions in an AlGaAs matrix

    SciTech Connect (OSTI)

    Ushanov, V. I.; Chaldyshev, V. V., E-mail: chald.gvg@mail.ioffe.ru [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Preobrazhenskii, V. V.; Putyato, M. A.; Semyagin, B. R. [Russian Academy of Sciences, Institute of Semiconductor Physics, Siberian Branch (Russian Federation)] [Russian Academy of Sciences, Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

    2013-08-15

    The optical properties of metal-semiconductor metamaterials based on an AlGaAs matrix are studied. The specific feature of these materials is that there are As and AsSb nanoinclusion arrays which modify the dielectric properties of the material. These nanoinclusions are randomly arranged in the medium or form a Bragg structure with a reflectance peak at a wavelength close to 750 nm, corresponding to the transparency region of the matrix. The reflectance spectra are studied for s- and p-polarized light at different angles of incidence. It is shown that (i) As nanoinclusion arrays only slightly influence the optical properties of the medium in the wavelength range 700-900 nm, (ii) chaotic AsSb nanoinclusion arrays cause strong scattering of light, and (iii) the spatial periodicity in the arrangement of AsSb nanoinclusions is responsible for Bragg resonance in the optical reflection.

  9. Structural and optical properties of Sb{sub 2}S{sub 3} nanocrystals in glass

    SciTech Connect (OSTI)

    Mishra, Rakesh K., E-mail: mishrarake@gmail.com; Kashyap, Raman, E-mail: mishrarake@gmail.com; Vedeshwar, A. G., E-mail: mishrarake@gmail.com; Tandon, R. P., E-mail: mishrarake@gmail.com [Department of Physics and Astrophysics, University of Delhi, Delhi 1-10007 (India)

    2014-04-24

    In this work conventional solid state precipitation method is adopted to fabricate Sb{sub 2}S{sub 3} nanocrystals in glass. The glass composition is optimized for proper host glass matrix to grow antimony trisulphide semiconductor quantum dots. The dot size is modified by heat treatment of glass samples in the temperature range from 550°C to 700°C for various time durations. Structural studies are carried out by X-ray diffraction and transmission electron microscopy and nanoparticles with size ranges from 8 nm to 70 nm are obtained. Quantum dots so grown were further characterized by optical absorption spectroscopy and a blue shift is observed for absorption edge energy that conform the quantum confinement effect.

  10. Electronic and optical properties of TiCoSb under different pressures

    SciTech Connect (OSTI)

    Xu Bin; Zhang Jing; Liang Jianchu; Gao Guoying; Yi Lin

    2012-08-15

    The electronic structure and optical properties of TiCoSb are studied by the first-principles calculation. It is found that the band gaps increase with the pressure increasing. It is noted that the increase of the band gap is due to the electrons of Ti 3d and Co 3d of the valence band (VB) shifting away from the Fermi level. Our calculation indicates that TiCoSb has the large density of state near the Fermi level; moreover, the changes of the density of states near the Fermi level mainly are caused by Ti 3d and Co 3d under the different pressures. It is noted that the absorption edge increases with an increase of pressure. As pressure increases, the static dielectric constants {epsilon}{sub 1}(0) decrease. All peaks of the imaginary part of the dielectric function {epsilon}{sub 2}({omega}) move towards higher energies within increasing pressure. - Graphical abstract: The first peak positions of the absorption spectrum increase and shift the high energy with an increase of pressure. The buleshift of the absorption edge could be observed. Highlights: Black-Right-Pointing-Pointer It is noted that the increase of the band gap is due to the electrons of Ti 3d and Co 3d of VB moving away from the Fermi level. Black-Right-Pointing-Pointer It is noted that the absorption edge increases with an increase of pressure. Black-Right-Pointing-Pointer As pressure increases, the static dielectric constant {epsilon}{sub 1}(0) decreases. Black-Right-Pointing-Pointer All peaks of the imaginary part of the dielectric function {epsilon}{sub 2}({omega}) move to wards higher energies within creasing pressure.

  11. Structural, electronic and optical properties of La{sub x}Sc{sub 1-x}Sb alloys

    SciTech Connect (OSTI)

    Ghezali, M.

    2015-03-30

    We present calculations of the structural, electronic and optic properties of LaxSc1-xSb ternary alloys for 0?x?1, by using the first principle full potential linear muffin-tin orbital (FPLMTO) method based on the local density approximation (LDA). the lattice constant, bulk modulus, electronic band structures, density of state and optical properties such as dielectric functions, refractive index and extinction coefficient are calculated and discussed for (x=0.25, 0.5 and 0.75). Our results agree well with the available data in the literature.

  12. Ab initio density functional theory investigation of the structural, electronic and optical properties of Ca{sub 3}Sb{sub 2} in hexagonal and cubic phases

    SciTech Connect (OSTI)

    Arghavani Nia, Borhan; Sedighi, Matin; Shahrokhi, Masoud; Moradian, Rostam

    2013-11-15

    A density functional theory study of structural, electronical and optical properties of Ca{sub 3}Sb{sub 2} compound in hexagonal and cubic phases is presented. In the exchange–correlation potential, generalized gradient approximation (PBE-GGA) has been used to calculate lattice parameters, bulk modulus, cohesive energy, dielectric function and energy loss spectra. The electronic band structure of this compound has been calculated using the above two approximations as well as another form of PBE-GGA, proposed by Engle and Vosko (EV-GGA). It is found that the hexagonal phase of Ca{sub 3}Sb{sub 2} has an indirect gap in the ??N direction; while in the cubic phase there is a direct-gap at the ? point in the PBE-GGA and EV-GGA. Effects of applying pressure on the band structure of the system studied and optical properties of these systems were calculated. - Graphical abstract: A density functional theory study of structural, electronic and optical properties of Ca{sub 3}Sb{sub 2} compound in hexagonal and cubic phases is presented. Display Omitted - Highlights: • Physical properties of Ca{sub 3}Sb{sub 2} in hexagonal and cubic phases are investigated. • It is found that the hexagonal phase is an indirect gap semiconductor. • Ca{sub 3}Sb{sub 2} is a direct-gap semiconductor at the ? point in the cubic phase. • By increasing pressure the semiconducting band gap and anti-symmetry gap are decreased.

  13. METR 3223: Physical Meteorology II: Cloud Physics, Atmospheric Electricity and Optics

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    METR 3223: Physical Meteorology II: Cloud Physics, Atmospheric Electricity and Optics CLASS: Monday as atmospheric electricity and optics. Specific topics that will be covered are as follows: Cloud physics: Review Lightening Atmospheric optics: Reflection and refraction Optical phenomena GRADES Homework problems: 20% Quiz

  14. METR 3223: Physical Meteorology II: Cloud Physics, Atmospheric Electricity and Optics

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    METR 3223: Physical Meteorology II: Cloud Physics, Atmospheric Electricity and Optics CLASS: Monday of the physical states and processes of clouds and precipitation as well as atmospheric electricity and optics Thunderstorm charging Lightening Atmospheric optics: Reflection and refraction Optical phenomena GRADES

  15. Spectral behavior of the optical constants in the visible/near infrared of GeSbSe chalcogenide thin films grown at glancing angle

    SciTech Connect (OSTI)

    Martin-Palma, R. J.; Ryan, Joseph V.; Pantano, C. G.

    2007-04-23

    GeSbSe chalcogenide thin films were deposited using glancing angle deposition onto transparent glass substrates for the determination of the spectral behavior of the optical constants (index of refraction n and extinction coefficient k) in the visible and near infrared ranges (400-2500 nm) as a function of the deposition angle. Computational simulations based on the matrix method were employed to determine the values of the optical constants of the different films from the experimental reflectance and transmittance spectra. A significant dependence of the overall optical behavior on the deposition angle is found. Furthermore, the band gap of the GeSbSe thin films was calculated. The accurate determination of the optical constants of films grown at glancing angle will enable the development of sculptured thin film fiber-optic chemical sensors and biosensors.

  16. Levitating atmospheres of Eddington-luminosity neutron stars I. Optically thin Thomson-scattering atmospheres

    E-Print Network [OSTI]

    Wielgus, M; S?dowski, A; Narayan, R; Abramowicz, M

    2015-01-01

    In general relativity static gaseous atmospheres may be in hydrostatic balance in the absence of a supporting stellar surface, provided that the luminosity is close to the Eddington value. We construct analytic models of optically thin, spherically symmetric shells supported by the radiation pressure of a luminous central body in the Schwarzschild metric.

  17. Levitating atmospheres of Eddington-luminosity neutron stars I. Optically thin Thomson-scattering atmospheres

    E-Print Network [OSTI]

    M. Wielgus; W. Klu?niak; A. S?dowski; R. Narayan; M. Abramowicz

    2015-05-22

    In general relativity static gaseous atmospheres may be in hydrostatic balance in the absence of a supporting stellar surface, provided that the luminosity is close to the Eddington value. We construct analytic models of optically thin, spherically symmetric shells supported by the radiation pressure of a luminous central body in the Schwarzschild metric.

  18. Structural and optical studies on AgSbSe{sub 2} thin films

    SciTech Connect (OSTI)

    Asokan, T. Namitha; Urmila, K. S.; Pradeep, B. [Solid State Physics Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi- 22, Kerala (India)

    2014-01-28

    AgSbSe{sub 2} semiconducting thin films are successfully deposited using reactive evaporation technique at a substrate temperature of 398K. X-ray diffraction studies reveal that the films are polycrystalline in nature. The structural parameters such as average particle size, dislocation density, and number of crystallites per unit have been evaluated. Atomic Force Microscopy is used to study the topographic characteristics of the film including the grain size and surface roughness. The silver antimony selenide thin films have high absorption coefficient of about 10{sup 5} cm{sup ?1} and it has an indirect band gap of 0.64eV.

  19. Determining Nighttime Atmospheric Optical Depth Using Mars Exploration Rover Images 

    E-Print Network [OSTI]

    Bean, Keri Marie

    2013-07-22

    was compared to the expected flux to give nighttime optical depth values. The observed nighttime optical depth was consistently similar to the daytime optical depth values on both an individual image and sol-averaged basis. Recommendations are made going...

  20. Optical Detection of Laser or Scattered Radiation Transmitted Through the Turbulent Atmosphere

    E-Print Network [OSTI]

    Teich, Malvin C.

    Optical Detection of Laser or Scattered Radiation Transmitted Through the Turbulent Atmosphere P. Diament and M. C. Teich Photoelectron counting distributions are obtained for radiation, consisting In recent work,' we have examined the counting statistics obtained for stochastic radiation caused

  1. Optical communication through the turbulent atmosphere with transmitter and receiver diversity, wavefront control, and coherent detection

    E-Print Network [OSTI]

    Puryear, Andrew Lee

    2011-01-01

    Free space optical communication through the atmosphere has the potential to provide secure, low-cost, rapidly deployable, dynamic, data transmission at very high rates. However, the deleterious effects of turbulence can ...

  2. Retrieval of optical and microphysical properties of ice clouds using Atmospheric Radiation Measurement (ARM) data 

    E-Print Network [OSTI]

    Kinney, Jacqueline Anne

    2005-11-01

    The research presented here retrieves the cloud optical thickness and particle effective size of cirrus clouds using surface radiation measurements obtained during the Atmospheric Radiation Measurement (ARM) field campaign. ...

  3. Comparison of optical emission from nanosecond and femtosecond laser produced plasma in atmosphere and vacuum conditions

    E-Print Network [OSTI]

    Harilal, S. S.

    Comparison of optical emission from nanosecond and femtosecond laser produced plasma in atmosphere November 2012 Accepted 12 May 2013 Available online 18 May 2013 Keywords: Optical emission spectroscopy In this study we examine the emission from brass plasma produced by ns and fs laser ablation under both vacuum

  4. Ohmic contacts to n-GaSb 

    E-Print Network [OSTI]

    Yang, Zhengchong

    1997-01-01

    In recent years, the Ill-V semiconductor GaSb and its ternary alloys containing antimony have exhibited interesting electrical and optical properties for device applications which include negative resistance tunnel devices, lasers, detectors and FET...

  5. Optical properties of AlAs{sub x}Sb{sub 1-x} alloys determined by in situ ellipsometry

    SciTech Connect (OSTI)

    Kim, J. Y.; Kim, T. J.; Kim, Y. D. [Nano-Optical Property Laboratory and Department of Physics, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Yoon, J. J.; Lee, E. H.; Bae, M. H.; Song, J. D.; Choi, W. J. [Center for Opto-Electronic Convergence Systems, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Liang, C.-T.; Chang, Y.-C. [Research Center for Applied Sciences, Academia Sinica, Taipei 115, Taiwan (China)

    2013-07-01

    We report pseudodielectric function data <{epsilon}> = <{epsilon}{sub 1}> + i<{epsilon}{sub 2}> from 0.74 to 6.48 eV of oxide-free AlAsSb alloys that are the closest representation to date of the intrinsic bulk dielectric response {epsilon} of the material. Measurements were performed on 1.3 {mu}m thick films grown on (001) GaAs substrates by molecular beam epitaxy. Data were obtained with the films in situ to avoid oxidation artifacts. Critical-point structures were identified by band-structure calculations done with the linear augmented Slater-type orbital method. Crossings of transitions at the {Gamma}- and X-points and the {Gamma}- and L-points with composition were observed.

  6. Lightweight Integrated Optical Sensor for Atmospheric Measurements on Mobile Platforms

    SciTech Connect (OSTI)

    Parameswaran, Krishnan R.

    2013-12-02

    The goal of the Phase I program was to develop a novel open path sensor platform technology based on integration of semiconductor waveguides with efficient optoelectronic components on a monolithic platform. The successful Phase I effort resulted in demonstration of a novel optical resonator structure based on semiconductor high contrast gratings (HCGs) that will enable implementation of an ultra-compact, low-power gas sensor suitable for use on mobile platforms. Extensive numerical modeling was performed to design a device optimized for measuring CO2 at a wavelength for which a laser was available for proof of concept. Devices were fabricated and tested to match the target wavelength, angle, and operating temperature. This demonstration is the first implementation of HCGs at the wavelengths of interest and shows the flexibility of the proposed architecture for gas sensing applications. The measured cavity Q was lower than anticipated due to fabrication process challenges. The PSI and UC Berkeley team has identified solutions to these challenges and will produce optimized devices in a Phase II program where a prototype sensor will be fabricated and tested.

  7. Accuracy of the Water Vapour Content Measurements in the Atmosphere Using Optical Methods

    E-Print Network [OSTI]

    Galkin, V D; Alekseeva, G A; Novikov, V V; Pakhomov, V P

    2010-01-01

    This paper describes the accuracy and the errors of water vapour content measurements in the atmosphere using optical methods, especially starphotometer. After the general explanations of the used expressions for the star-magnitude observations of the water vapour absorption in section 3 the absorption model for the water vapour band will be discussed. Sections 4 and 5 give an overview on the technique to determine the model parameters both from spectroscopic laboratory and radiosonde observation data. Finally, the sections 6 and 7 are dealing with the details of the errors; that means errors of observable magnitude, of instrumental extraterrestrial magnitude, of atmospheric extinction determination and of water vapour content determination by radiosonde humidity measurements. The main conclusion is: Because of the high precision of the results the optical methods for water vapour observation are suited to validate and calibrate alternative methods (GPS, LIDAR, MICROWAVE) which are making constant progress wo...

  8. The optical reflector system for the CANGAROO-II imaging atmospheric Cherenkov telescope

    E-Print Network [OSTI]

    A. Kawachi; Y. Hayami; J. Jimbo; S. Kamei; T. Kifune; H. Kubo; J. Kushida; S. LeBohec; K. Miyawaki; M. Mori; K. Nishijima; J. R. Patterson; R. Suzuki; T. Tanimori; S. Yanagita; T. Yoshikoshi; A. Yuki

    2000-07-14

    A new imaging atmospheric Cherenkov telescope (CANGAROO-II) with a light-weight reflector has been constructed. Light, robust, and durable mirror facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were developed for the telescope. The attitude of each facet can be adjusted by stepping motors. In this paper, we describe the design, manufacturing, alignment procedure, and the performance of the CANGAROO-II optical reflector system.

  9. The optical reflector system for the CANGAROO-II imaging atmospheric Cherenkov telescope

    E-Print Network [OSTI]

    Kawachi, A; Jimbo, J; Kamei, S; Kifune, T; Kubo, H; Kushida, J; Le Bohec, S; Miyawaki, K; Mori, M; Nishijima, K; Patterson, J R; Suzuki, R; Tanimori, T; Yanagita, S; Yoshikoshi, T; Yuki, A

    2001-01-01

    A new imaging atmospheric Cherenkov telescope (CANGAROO-II) with a light-weight reflector has been constructed. Light, robust, and durable mirror facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were developed for the telescope. The attitude of each facet can be adjusted by stepping motors. In this paper, we describe the design, manufacturing, alignment procedure, and the performance of the CANGAROO-II optical reflector system.

  10. Clouds and Chemistry: Ultracool Dwarf Atmospheric Properties from Optical and Infrared Colors

    E-Print Network [OSTI]

    M. S. Marley; S. Seager; D. Saumon; K. Lodders; A. S. Ackerman; R. Freedman; X Fan

    2001-11-16

    The optical and infrared colors of L and T dwarfs are sensitive to cloud sedimentation and chemical equilibrium processes in their atmospheres. The i'-z' vs. J-K color-color diagram provides a window into diverse atmospheric processes mainly because different chemical processes govern each color, and cloud opacity largely affects J-K but not i'-z'. Using theoretical atmosphere models that include for the first time a self-consistent treatment of cloud formation, we present an interpretation of the i'-z' vs. J-K color trends of known L and T dwarfs. We find that the i'-z' color is extremely sensitive to chemical equilibrium assumptions: chemical equilibrium models accounting for cloud sedimentation predict redder i'-z' colors--by up to 2 magnitudes--than models that neglect sedimentation. We explore the previously known J-K color trends where objects first become redder, then bluer with decreasing effective temperature. Only models that include sedimentation of condensates are able to reproduce these trends. We find that the exact track of a cooling brown in J-K (and i'-z') is very sensitive to the details of clouds, in particular to the efficiency of sedimentation of condensates in its atmosphere. We also find that clouds still affect the strength of the J, H, and K band fluxes of even the coolest T dwarfs. In addition, we predict the locus in the i'-z' vs. J-K color-color diagram of brown dwarfs cooler than yet discovered.

  11. The Precipitation of Sb2Te3 in Sb-rich AgSbTe2 via the Intermediate...

    Office of Scientific and Technical Information (OSTI)

    The Precipitation of Sb2Te3 in Sb-rich AgSbTe2 via the Intermediate Phase (AgSb)3Te4. Citation Details In-Document Search Title: The Precipitation of Sb2Te3 in Sb-rich AgSbTe2 via...

  12. Development of an electronic device quality aluminum antimonide (AlSb) semiconductor for solar cell applications

    DOE Patents [OSTI]

    Sherohman, John W; Yee, Jick Hong; Combs, III, Arthur W

    2014-11-11

    Electronic device quality Aluminum Antimonide (AlSb)-based single crystals produced by controlled atmospheric annealing are utilized in various configurations for solar cell applications. Like that of a GaAs-based solar cell devices, the AlSb-based solar cell devices as disclosed herein provides direct conversion of solar energy to electrical power.

  13. Studies of Atmospheric Chemistry and Reaction Mechanisms Using Optical Spectroscopy and Mass Spectrometry

    E-Print Network [OSTI]

    Liu, Yingdi

    2011-01-01

    challenges in analytical chemistry of the atmosphere. Anal.amplification. Analytical Chemistry, 1984. 56(8): p.radical measurements. Analytical Chemistry, 1996. 68(23): p.

  14. Low loss hollow optical-waveguide connection from atmospheric pressure to ultra-high vacuum

    SciTech Connect (OSTI)

    Ermolov, A.; Mak, K. F.; Tani, F.; Hölzer, P.; Travers, J. C. [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany)] [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Russell, P. St. J. [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany) [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Department of Physics, University of Erlangen-Nuremberg, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany)

    2013-12-23

    A technique for optically accessing ultra-high vacuum environments, via a photonic-crystal fiber with a long small hollow core, is described. The small core and the long bore enable a pressure ratio of over 10{sup 8} to be maintained between two environments, while permitting efficient and unimpeded delivery of light, including ultrashort optical pulses. This delivery can be either passive or can encompass nonlinear optical processes such as optical pulse compression, deep UV generation, supercontinuum generation, or other useful phenomena.

  15. Modeling of the optical properties of nonspherical particles in the atmosphere 

    E-Print Network [OSTI]

    Chen, Guang

    2009-05-15

    The single scattering properties of atmospheric particles are fundamental to radiative simulations and remote sensing applications. In this study, an efficient technique, namely, the pseudo-spectral time-domain (PSTD) ...

  16. Effect of Solar Radiation on the Optical Properties and Molecular Composition of Laboratory Proxies of Atmospheric Brown Carbon

    SciTech Connect (OSTI)

    Lee, Hyun Ji; Aiona, Paige K.; Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey

    2014-09-02

    Sources, optical properties, and chemical composition of atmospheric brown carbon (BrC) aerosol are uncertain, making it challenging to estimate its contribution to radiative forcing. Furthermore, optical properties of BrC may change significantly during its atmospheric aging. We examined the effect of solar photolysis on the molecular composition, mass absorption coefficient, and fluorescence of secondary organic aerosol prepared by high-NOx photooxidation of naphthalene (NAP SOA). The aqueous solutions of NAP SOA was observed to photobleach with an effective half-time of ?15 hours (with sun in its zenith) for the loss of the near-UV (300 -400 nm) absorbance. The molecular composition of NAP SOA was significantly modified by photolysis, with the average SOA formula changing from C14.1H14.5O5.1N0.08 to C11.8H14.9O4.5N0.02 after 4 hours of irradiation. The average O/C ratio did not change significantly, however, suggesting that it is not a good metric for assessing the extent of photolysis-driven aging in NAP SOA (and in BrC in general). In contrast to NAP SOA, the photolysis of BrC material produced by aqueous reaction of limonene+O3 SOA (LIM/O3 SOA) with ammonium sulfate was much faster, but it did not result in a significant change in the molecular level composition. The characteristic absorbance of the aged LIM/O3 SOA in the 450-600 nm range decayed with an effective half-time of <0.5 hour. This result emphasizes the highly variable and dynamic nature of different types of atmospheric BrC.

  17. CRAD, NNSA- Safety Basis (SB)

    Broader source: Energy.gov [DOE]

    CRAD for Safety Basis (SB). Criteria Review and Approach Documents (CRADs) that can be used to conduct a well-organized and thorough assessment of elements of safety and health programs.

  18. Soft x ray/extreme ultraviolet images of the solar atmosphere with normal incidence multilayer optics

    SciTech Connect (OSTI)

    Lindblom, J.F.

    1990-01-01

    The first high resolution Soft X-Ray/Extreme Ultraviolet (XUV) images of the Sun with normal incidence multilayer optics were obtained by the Standford/MSFC Rocket X-Ray Spectroheliograph on 23 Oct. 1987. Numerous images at selected wavelengths from 8 to 256 A were obtained simultaneously by the diverse array of telescopes flown on-board the experiment. These telescopes included single reflection normal incidence multilayer systems (Herschelian), double reflection multilayer systems (Cassegrain), a grazing incidence mirror system (Wolter-Schwarzschild), and hybrid systems using normal incidence multilayer optics in conjunction with the grazing incidence primary (Wolter-Cassegrain). Filters comprised of approximately 1700{Angstrom} thick aluminum supported on a nickel mesh were used to transmit the soft x ray/EUV radiation while preventing the intense visible light emission of the Sun from fogging the sensitive experimental T-grain photographic emulsions. These systems yielded high resolution soft x ray/EUV images of the solar corona and transition region, which reveal magnetically confined loops of hot solar plasma, coronal plumes, polar coronal holes, supergranulation, and features associated with overlying cool prominences. The development, testing, and operation of the experiments, and the results from the flight are described. The development of a second generation experiment, the Multi-Spectral Solar Telescope Array, which is scheduled to fly in the summer of 1990, and a recently approved Space Station experiment, the Ultra-High Resolution XUV Spectroheliograph, which is scheduled to fly in 1996 are also described.

  19. Relaxation of photoinduced spins and carriers in ferromagnetic InMnSb films

    SciTech Connect (OSTI)

    Nontapot, K.; Kini, R. N.; Gifford, A.; Merritt, T. R.; Khodaparast, G. A.; Wojtowicz, T.; Liu, X.; Furdyna, J. K. [Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States); Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw (Poland); Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2007-04-02

    The authors report time resolved measurements and control of photoinduced spin and carrier relaxations in InMnSb ferromagnetic films with 2% Mn content (grown by low-temperature molecular beam epitaxy) using femtosecond laser pulses, and compare them to analogous measurements on InBeSb and InSb films. In this work, magneto-optical Kerr effect and standard pump-probe techniques provided a direct measure of the photoexcited spin and carrier lifetimes, respectively. They observe decrease in relaxations times in the high laser fluence regime and an absence of temperature dependence of the relaxation times.

  20. Electronic and structural response of InSb to ultra-short and ultra-intense laser pulses 

    E-Print Network [OSTI]

    Burzo, Andrea Mihaela

    2001-01-01

    The present work is motivated in part by the increasing interest in a better understanding of the optical properties of InSb, the main material used to manufacture infrared detectors. In addition, there have been recent ...

  1. Long-Term, Autonomous Measurement of Atmospheric Carbon Dioxide Using an Ormosil Nanocomposite-Based Optical Sensor

    SciTech Connect (OSTI)

    Kisholoy Goswami

    2005-10-11

    The goal of this project is to construct a prototype carbon dioxide sensor that can be commercialized to offer a low-cost, autonomous instrument for long-term, unattended measurements. Currently, a cost-effective CO2 sensor system is not available that can perform cross-platform measurements (ground-based or airborne platforms such as balloon and unmanned aerial vehicle (UAV)) for understanding the carbon sequestration phenomenon. The CO2 sensor would support the research objectives of DOE-sponsored programs such as AmeriFlux and the North American Carbon Program (NACP). Global energy consumption is projected to rise 60% over the next 20 years and use of oil is projected to increase by approximately 40%. The combustion of coal, oil, and natural gas has increased carbon emissions globally from 1.6 billion tons in 1950 to 6.3 billion tons in 2000. This figure is expected to reach 10 billon tons by 2020. It is important to understand the fate of this excess CO2 in the global carbon cycle. The overall goal of the project is to develop an accurate and reliable optical sensor for monitoring carbon dioxide autonomously at least for one year at a point remote from the actual CO2 release site. In Phase I of this project, InnoSense LLC (ISL) demonstrated the feasibility of an ormosil-monolith based Autonomous Sensor for Atmospheric CO2 (ASAC) device. All of the Phase I objectives were successfully met.

  2. High-temperature luminescence in an n-GaSb/n-InGaAsSb/p-AlGaAsSb light-emitting heterostructure with a high potential barrier

    SciTech Connect (OSTI)

    Petukhov, A. A., E-mail: andrey-rus29@rambler.ru; Zhurtanov, B. E.; Kalinina, K. V.; Stoyanov, N. D.; Salikhov, H. M.; Mikhailova, M. P.; Yakovlev, Yu. P. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)] [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2013-09-15

    The electroluminescent properties of an n-GaSb/n-InGaAsSb/p-AlGaAsSb heterostructure with a high potential barrier in the conduction band (large conduction-band offset) at the n-GaSb/n-InGaAsSb type-II heterointerface ({Delta}E{sub c} = 0.79 eV) are studied. Two bands with peaks at 0.28 and 0.64 eV at 300 K, associated with radiative recombination in n-InGaAsSb and n-GaSb, respectively, are observed in the electroluminescence (EL) spectrum. In the entire temperature range under study, T = 290-480 K, additional electron-hole pairs are formed in the n-InGaAsSb active region by impact ionization with hot electrons heated as a result of the conduction-band offset. These pairs contribute to radiative recombination, which leads to a nonlinear increase in the EL intensity and output optical power with increasing pump current. A superlinear increase in the emission power of the long-wavelength band is observed upon heating in the temperature range T = 290-345 K, and a linear increase is observed at T > 345 K. This work for the first time reports an increase in the emission power of a light-emitting diode structure with increasing temperature. It is shown that this rise is caused by a decrease in the threshold energy of the impact ionization due to narrowing of the band gap of the active region.

  3. Quaternary InGaAsSb Thermophotovoltaic Diodes

    SciTech Connect (OSTI)

    MW Dashiell; JF Beausang; H Ehsani; GJ Nichols; DM Depoy; LR Danielson; P Talamo; KD Rahner; EJ Brown; SR Burger; PM Foruspring; WF Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; J Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryi

    2006-03-09

    In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature of T{sub diode} = 27 C, and diode bandgap of E{sub G} = 0.53eV. Practical limits to TPV energy conversion efficiency are established using measured recombination coefficients and optical properties of front surface spectral control filters, which for 0.53eV InGaAsSb TPV energy conversion is {eta}{sub TPV} = 28% and PD = 0.85W/cm{sup 2} at the above operating temperatures. The most severe performance limits are imposed by (1) diode open-circuit voltage (VOC) limits due to intrinsic Auger recombination and (2) parasitic photon absorption in the inactive regions of the module. Experimentally, the diode V{sub OC} is 15% below the practical limit imposed by intrinsic Auger recombination processes. Analysis of InGaAsSb diode electrical performance vs. diode architecture indicate that the V{sub OC} and thus efficiency is limited by extrinsic recombination processes such as through bulk defects.

  4. Phase transitions in Ge-Sb phase change materials

    SciTech Connect (OSTI)

    Raoux, Simone; Virwani, Kumar; Hitzbleck, Martina; Salinga, Martin; Madan, Anita; Pinto, Teresa L.

    2009-03-15

    Thin films of the phase change material Ge-Sb with Ge concentrations between 7.3 and 81.1 at. % were deposited by cosputtering from elemental targets. Their crystallization behavior was studied using time-resolved x-ray diffraction, Auger electron spectroscopy, differential scanning calorimetry, x-ray reflectivity, profilometry, optical reflectivity, and resistivity versus temperature measurements. It was found that the crystallization temperature increases with Ge content. Calculations of the glass transition temperature (which is a lower limit for the crystallization temperature T{sub x}) also show an increase with Ge concentration closely tracking the measured values of T{sub x}. For low Ge content samples, Sb x-ray diffraction peaks occurred during a heating ramp at lower temperature than Ge diffraction peaks. The appearance of Ge peaks is related to Ge precipitation and agglomeration. For Ge concentrations of 59.3 at. % and higher, Sb and Ge peaks occurred at the same temperature. Upon crystallization, film mass density and optical reflectivity increase as well as electrical contrast (ratio of resistivity in amorphous phase to crystalline phase) all showed a maximum for the eutectic alloy (14.5 at. % Ge). For the alloy with 59.3 at. % Ge there was very little change in any of these parameters, while the alloy with 81.1 at. % Ge behaved opposite to a typical phase change alloy and showed reduced mass density and reflectivity and increased resistivity.

  5. AlGaAsSb/GaSb Distributed Bragg Reflectors Grown by Organometallic Vapor Phase Epitaxy

    SciTech Connect (OSTI)

    C.A. Wang; C.J. Vineis; D.R. Calawa

    2002-02-13

    The first AlGaAsSb/GaSb quarter-wave distributed Bragg reflectors grown by metallic vapor phase epitaxy are reported. The peak reflectance is 96% for a 10-period structure.

  6. Transport properties in AlInSb/InAsSb heterostructures

    SciTech Connect (OSTI)

    Zhang, Yuwei; Zhang, Yang, E-mail: zhang-yang@semi.ac.cn; Wang, Chengyan; Zeng, Yiping [Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2013-12-28

    Based on theoretical studies of transport properties in InAsSb-based quantum well heterostructures, we propose a material design for InAsSb quantum well with AlInSb barrier. Variation of electron mobility and two-dimensional electron gas concentration in Al{sub y}In{sub 1?y}Sb/InAs{sub 1?x}Sb{sub x} heterostructures over the compositional range of which InAsSb is fully strained to AlInSb are investigated, where impact from dislocation scattering could be minimized. In comparison with InAs and InSb based quantum well heterostructures, InAsSb is advantageous in achieving the highest electron mobility despite of alloy disorder scattering. The maximum mobility of 37?000 cm{sup 2}/V s is attainable in 15?nm InAs{sub 0.2}Sb{sub 0.8} quantum well with Al{sub 0.24}In{sub 0.76}Sb barrier and there is great potential for further improvement. Our InAsSb based quantum well heterostructure is proved to be a robust structure for high-speed applications.

  7. The FALCON concept: multi-object adaptive optics and atmospheric tomography for integral field spectroscopy. Principles and performances on an 8 meter telescope

    E-Print Network [OSTI]

    Francois Assemat; Eric Gendron; Francois Hammer

    2006-12-19

    Integral field spectrographs are major instruments to study the mechanisms involved in the formation and the evolution of early galaxies. When combined with multi-object spectroscopy, those spectrographs can behave as machines used to derive physical parameters of galaxies during their formation process. Up to now, there is only one available spectrograph with multiple integral field units, e.g. FLAMES/GIRAFFE on the VLT. However, current ground based instruments suffer from a degradation of their spatial resolution due to atmospheric turbulence. In this article we describe the performance of FALCON, an original concept of a new generation multi-object integral field spectrograph with adaptive optics for the ESO Very Large Telescope. The goal of FALCON is to combine high angular resolution (0.25 arcsec) and high spectral resolution (R > 5000) in J and H bands over a wide field of view (10x10 arcmin2) in the VLT Nasmyth focal plane. However, instead of correcting the whole field, FALCON will use multi-object adaptive optics (MOAO) to perform locally on each scientific target the adaptive optics correction. This requires then to use atmospheric tomography in order to use suitable natural guide stars for wavefront sensing. We will show that merging MOAO and atmospheric tomography allows us to determine the internal kinematics of distant galaxies up to z=2 with a sky coverage of 50%, even for objects observed near the galactic pole. The application of such a concept to Extremely Large Telescopes seems therefore to be a very promising way to study galaxy evolution from z = 1 to redshifts as high as z = 7.

  8. Structural investigation on Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses using x-ray photoelectron spectra

    SciTech Connect (OSTI)

    Wei, Wen-Hou [Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Xiang, Shen [College of Information Science and Engineering, Ningbo University, Ningbo 315211 (China); Xu, Si-Wei; Wang, Rong-Ping, E-mail: rongping.wang@anu.edu.au [Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Fang, Liang [Department of Applied Physics, Chongqing University, Chongqing 401331 (China)

    2014-05-14

    The structure of Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses (x?=?7.5, 10, 15, 20, 25, 27.5, 30, and 32.5 at. %) has been investigated by x-ray photoelectron spectroscopy (XPS). Different structural units have been extracted and characterized by decomposing XPS core level spectra, the evolution of the relative concentration of each structural unit indicates that, the relative contributions of Se-trimers and Se-Se-Ge(Sb) structure decrease with increasing Ge content until they become zero at chemically stoichiometric glasses of Ge{sub 25}Sb{sub 10}Se{sub 65}, and then the homopolar bonds like Ge-Ge and Sb-Sb begin to appear in the spectra. Increase of homopolar bonds will extend band-tails into the gap and narrow the optical band gap. Thus, the glass with a stoichiometric composition generally has fewer defective bonds and larger optical bandgap.

  9. Effect of Solar Radiation on the Optical Properties and Molecular Composition of Laboratory Proxies of Atmospheric Brown Carbon

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    Effect of Solar Radiation on the Optical Properties and Molecular Composition of Laboratory Proxies, making it challenging to estimate its contribution to radiative forcing. Furthermore, optical properties were observed to photobleach (i.e., lose their ability to absorb visible radiation) with an effective

  10. Electrochemical Insertion/extraction of Lithium in Multiwall Carbon Nanotube/Sb and SnSb?.? Nanocomposites

    E-Print Network [OSTI]

    Chen, Wei Xiang

    Multiwall carbon nanotubes (CNTs) were synthesized by catalytic chemical vapor deposition of acetylene and used as templates to prepare CNT-Sb and CNT-SnSb?.? nanocomposites via the chemical reduction of SnCl? and SbCl? ...

  11. InGaAsSb thermophotovoltaic diode physics evaluation

    SciTech Connect (OSTI)

    Charache, G.W.; Baldasaro, P.F.; Danielson, L.R. [Lockheed-Martin, Inc., Schenectady, NY (United States)] [and others

    1998-06-01

    The hotside operating temperatures for many projected thermophotovoltaic (TPV) conversion system applications are approximately 1,000 C, which sets an upper limit on the TPV diode bandgap of 0.6 eV from efficiency and power density considerations. This bandgap requirement has necessitated the development of new diode material systems, never previously considered for energy generation. To date, InGaAsSb quaternary diodes grown lattice-matched on GaSb substrates have achieved the highest performance. This report relates observed diode performance to electro-optic properties such as minority carrier lifetime, diffusion length and mobility and provides initial links to microstructural properties. This analysis has bounded potential diode performance improvements. For the 0.52 eV InGaAsSb diodes used in this analysis the measured dark current is 2 {times} 10{sup {minus}5} A/cm{sup 2}, versus a potential Auger limit 1 {times} 10{sup {minus}5} A/cm{sup 2}, a radiative limit of 2 {times} 10{sup {minus}6} A/cm{sup 2} (no photon recycling), and an absolute thermodynamic limit of 1.4 {times} 10{sup {minus}7} A/cm{sup 2}. These dark currents are equivalent to open circuit voltage gains of 20 mV (7%), 60 mV (20%) and 140 mV (45%), respectively.

  12. Temperature dependence of the dielectric response of AlSb

    SciTech Connect (OSTI)

    Jung, Y. W.; Kim, T. J.; Kim, Y. D.; Shin, S. H.; Kim, S. Y.; Song, J. D.

    2011-12-23

    Spectroscopic ellipometry was used to determine the optical response of an intrinsic AlSb film as a function of temperature. The 1.5 {mu}m thick film was grown on a (001) GaAs substrate by molecular beam epitaxy. Measurements were done at temperatures from 300 K to the growth temperature of 800 K over a spectral range of 0.7 to 5.0 eV. To avoid oxidation artifacts, measurements were done with the film in situ. The data were analyzed using a parametric semiconductor model for its temperature dependence.

  13. SbSI nanocrystal formation in As–Sb–S–I glass under laser beam

    SciTech Connect (OSTI)

    Azhniuk, Yu.M.; Stoyka, V.; Petryshynets, I.; Rubish, V.M.; Guranich, O.G.; Gomonnai, A.V.; Zahn, D.R.T.

    2012-06-15

    Highlights: ? As–Sb–S–I glasses are obtained by co-melting of As{sub 2}S{sub 3} and SbSI. ? The glass structure and composition are confirmed by SEM, EDX, and Raman studies. ? Laser-induced crystallization of SbSI from the glass is observed by Raman spectroscopy. -- Abstract: As–Sb–S–I glasses are obtained by co-melting of As{sub 2}S{sub 3} and SbSI in a broad compositional interval. Their structure and composition are confirmed by the studies of scanning electron microscopy, energy dispersive X-ray spectroscopy, and micro-Raman scattering. Laser-induced crystallization of SbSI crystallites from the glass matrix is observed in the course of the micro-Raman measurement as a result of local laser beam heating.

  14. Growth mechanisms of GaSb heteroepitaxial films on Si with an AlSb buffer layer

    SciTech Connect (OSTI)

    Vajargah, S. Hosseini; Botton, G. A.; Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4M1; Canadian Centre for Electron Microscopy, McMaster University, Hamilton, Ontario L8S 4M1 ; Ghanad-Tavakoli, S.; Preston, J. S.; Kleiman, R. N.; Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7; Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4L7

    2013-09-21

    The initial growth stages of GaSb epilayers on Si substrates and the role of the AlSb buffer layer were studied by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Heteroepitaxy of GaSb and AlSb on Si both occur by Volmer-Weber (i.e., island mode) growth. However, the AlSb and GaSb islands have distinctly different characteristics as revealed through an atomic-resolution structural study using Z-contrast of HAADF-STEM imaging. While GaSb islands are sparse and three dimensional, AlSb islands are numerous and flattened. The introduction of 3D island-forming AlSb buffer layer facilitates the nucleation of GaSb islands. The AlSb islands-assisted nucleation of GaSb islands results in the formation of drastically higher quality planar film at a significantly smaller thickness of films. The interface of the AlSb and GaSb epilayers with the Si substrate was further investigated with energy dispersive X-ray spectrometry to elucidate the key role of the AlSb buffer layer in the growth of GaSb epilayers on Si substrates.

  15. Semiconductor structures having electrically insulating and conducting portions formed from an AlSb-alloy layer

    DOE Patents [OSTI]

    Spahn, Olga B. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM)

    1998-01-01

    A semiconductor structure. The semiconductor structure comprises a plurality of semiconductor layers formed on a substrate including at least one layer of a III-V compound semiconductor alloy comprising aluminum (Al) and antimony (Sb), with at least a part of the AlSb-alloy layer being chemically converted by an oxidation process to form superposed electrically insulating and electrically conducting portions. The electrically insulating portion formed from the AlSb-alloy layer comprises an oxide of aluminum (e.g. Al.sub.2 O.sub.3), while the electrically conducting portion comprises Sb. A lateral oxidation process allows formation of the superposed insulating and conducting portions below monocrystalline semiconductor layers for forming many different types of semiconductor structures having particular utility for optoelectronic devices such as light-emitting diodes, edge-emitting lasers, vertical-cavity surface-emitting lasers, photodetectors and optical modulators (waveguide and surface normal), and for electronic devices such as heterojunction bipolar transistors, field-effect transistors and quantum-effect devices. The invention is expected to be particularly useful for forming light-emitting devices for use in the 1.3-1.6 .mu.m wavelength range, with the AlSb-alloy layer acting to define an active region of the device and to effectively channel an electrical current therein for efficient light generation.

  16. Abundance analysis of SB2 binary stars with HgMn primaries

    E-Print Network [OSTI]

    T. Ryabchikova

    1998-05-06

    We present a short review of the abundances in the atmospheres of SB2 systems with Mercury-Manganese (HgMn) primaries. Up to now a careful study has been made for both components of 8 out of 17 known SB2 binaries with orbital periods shorter than 100 days and mass ratio ranging from 1.08 to 2.2. For all eight systems we observe a lower Mn abundance in the secondary's atmospheres than in the primary's. Significant difference in the abundances is also found for some peculiar elements such as Ga, Xe, Pt. All secondary stars with effective temperatures less than 10000 K show abundance characteristics typical of the metallic-line stars.

  17. DWPF simulant CPC studies for SB8

    SciTech Connect (OSTI)

    Koopman, D. C.; Zamecnik, J. R.

    2013-06-25

    The Savannah River National Laboratory (SRNL) accepted a technical task request (TTR) from Waste Solidification Engineering to perform simulant tests to support the qualification of Sludge Batch 8 (SB8) and to develop the flowsheet for SB8 in the Defense Waste Processing Facility (DWPF). These efforts pertained to the DWPF Chemical Process Cell (CPC). Separate studies were conducted for frit development and glass properties (including REDOX). The SRNL CPC effort had two primary phases divided by the decision to drop Tank 12 from the SB8 constituents. This report focuses on the second phase with SB8 compositions that do not contain the Tank 12 piece. A separate report will document the initial phase of SB8 testing that included Tank 12. The second phase of SB8 studies consisted of two sets of CPC studies. The first study involved CPC testing of an SB8 simulant for Tank 51 to support the CPC demonstration of the washed Tank 51 qualification sample in the SRNL Shielded Cells facility. SB8-Tank 51 was a high iron-low aluminum waste with fairly high mercury and moderate noble metal concentrations. Tank 51 was ultimately washed to about 1.5 M sodium which is the highest wash endpoint since SB3-Tank 51. This study included three simulations of the DWPF Sludge Receipt and Adjustment Tank (SRAT) cycle and Slurry Mix Evaporator (SME) cycle with the sludge-only flowsheet at nominal DWPF processing conditions and three different acid stoichiometries. These runs produced a set of recommendations that were used to guide the successful SRNL qualification SRAT/SME demonstration with actual Tank 51 washed waste. The second study involved five SRAT/SME runs with SB8-Tank 40 simulant. Four of the runs were designed to define the acid requirements for sludge-only processing in DWPF with respect to nitrite destruction and hydrogen generation. The fifth run was an intermediate acid stoichiometry demonstration of the coupled flowsheet for SB8. These runs produced a set of processing recommendations for DWPF along with some data related to Safety Class documentation at DWPF. Some significant observations regarding SB8 follow: Reduced washing in Tank 51 led to an increase in the wt.% soluble solids of the DWPF feed. If wt.% total solids for the SRAT and SME product weren’t adjusted upward to maintain insoluble solids levels similar to past sludge batches, then the rheological properties of the slurry went below the low end of the DWPF design bases for the SRAT and SME. Much higher levels of dissolved manganese were found in the SRAT and SME products than in recent sludge batches. Closed crucible melts were more reduced than expected. The working hypothesis is that the soluble Mn is less oxidizing than assumed in the REDOX calculations. A change in the coefficient for Mn in the REDOX equation was recommended in a separate report. The DWPF (Hsu) stoichiometric acid equation was examined in detail to better evaluate how to control acid in DWPF. The existing DWPF equation can likely be improved without changing the required sample analyses through a paper study using existing data. The recommended acid stoichiometry for initial SB8 SRAT batches is 115-120% stoichiometry until some processing experience is gained. The conservative range (based on feed properties) of stoichiometric factors derived in this study was from 110-147%, but SRNL recommends using only the lower half of this range, 110-126% even after initial batches provide processing experience. The stoichiometric range for sludge-only processing appears to be suitable for coupled operation based on results from the run in the middle of the range. Catalytic hydrogen was detectable (>0.005 vol%) in all SRAT and SME cycles. Hydrogen reached 30-35% of the SRAT and SME limits at the mid-point of the stoichiometry window (bounding noble metals and acid demand).

  18. Properties of Sb{sub 2}S{sub 3} and Sb{sub 2}Se{sub 3} thin films obtained by pulsed laser ablation

    SciTech Connect (OSTI)

    Virt, I. S.; Rudyj, I. O.; Kurilo, I. V.; Lopatynskyi, I. Ye.; Linnik, L. F.; Tetyorkin, V. V.; Potera, P.; Luka, G.

    2013-07-15

    The properties of Sb{sub 2}S{sub 3} and Sb{sub 2}Se{sub 3} thin films of variable thickness deposited onto Al{sub 2}O{sub 3}, Si, and KCl substrates are investigated by the method of pulsed laser ablation. The samples are obtained at a substrate temperature of 180 Degree-Sign C in a vacuum chamber with a residual pressure of 10{sup -5} Torr. The thickness of the films amounted to 40-1500 nm. The structure of the bulk material of the targets and films is investigated by the methods of X-ray diffraction and transmission high-energy electron diffraction, respectively. The electrical properties of the films are investigated in the temperature range of 253-310 K. It is shown that the films have semiconductor properties. The structural features of the films determine their optical parameters.

  19. Atmospheric Environment ] (

    E-Print Network [OSTI]

    Raman, Sethu

    that the influence of the urban region on wind patterns and atmospheric stability could be studied. HeightAtmospheric Environment ] (

  20. SB 375 IMPLEMENTATION: FROM PLAN TO REALITY

    E-Print Network [OSTI]

    California at Davis, University of

    sustainable communities in a post-SB 375 world. · Urban Greening: $41.5 million in capital projects and plans Development Cross-Agency Facilitation and Coordination Funding and Support for Sustainable Communities connections between state, local, and regional agencies - Tools and guidance - Sustainable Communities

  1. Interband magneto-spectroscopy in InSb square and parabolic quantum wells

    SciTech Connect (OSTI)

    Kasturiarachchi, T.; Edirisooriya, M.; Mishima, T. D.; Doezema, R. E.; Santos, M. B.; Saha, D.; Pan, X.; Sanders, G. D.; Stanton, C. J.

    2015-06-07

    We measure the magneto-optical absorption due to intersubband optical transitions between conduction and valence subband Landau levels in InSb square and parabolic quantum wells. InSb has the narrowest band gap (0.24?eV at low temperature) of the III–V semiconductors leading to a small effective mass (0.014 m{sub 0}) and a large g–factor (?51). As a result, the Landau level spacing is large at relatively small magnetic fields (<8?T), and one can observe spin-splitting of the Landau levels. We examine two structures: (i) a multiple-square-well structure and (ii) a structure containing multiple parabolic wells. The energies and intensities of the strongest features are well explained by a modified Pidgeon-Brown model based on an 8-band k•p model that explicitly incorporates pseudomorphic strain. The strain is essential for obtaining agreement between theory and experiment. While modeling the square well is relatively straight-forward, the parabolic well consists of 43 different layers of various thickness to approximate a parabolic potential. Agreement between theory and experiment for the parabolic well validates the applicability of the model to complicated structures, which demonstrates the robustness of our model and confirms its relevance for developing electronic and spintronic devices that seek to exploit the properties of the InSb band structure.

  2. InAs quantum dot morphology after capping with In, N, Sb alloyed thin films

    SciTech Connect (OSTI)

    Keizer, J. G.; Koenraad, P. M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven (Netherlands); Ulloa, J. M.; Utrilla, A. D. [Institute for Systems based on Optoelectronics and Microtechnology (ISOM), Universidad Politecnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2014-02-03

    Using a thin capping layer to engineer the structural and optical properties of InAs/GaAs quantum dots (QDs) has become common practice in the last decade. Traditionally, the main parameter considered has been the strain in the QD/capping layer system. With the advent of more exotic alloys, it has become clear that other mechanisms significantly alter the QD size and shape as well. Larger bond strengths, surfactants, and phase separation are known to act on QD properties but are far from being fully understood. In this study, we investigate at the atomic scale the influence of these effects on the morphology of capped QDs with cross-sectional scanning tunneling microscopy. A broad range of capping materials (InGaAs, GaAsSb, GaAsN, InGaAsN, and GaAsSbN) are compared. The QD morphology is related to photoluminescence characteristics.

  3. DWPF Simulant CPC Studies For SB8

    SciTech Connect (OSTI)

    Newell, J. D.

    2013-09-25

    Prior to processing a Sludge Batch (SB) in the Defense Waste Processing Facility (DWPF), flowsheet studies using simulants are performed. Typically, the flowsheet studies are conducted based on projected composition(s). The results from the flowsheet testing are used to 1) guide decisions during sludge batch preparation, 2) serve as a preliminary evaluation of potential processing issues, and 3) provide a basis to support the Shielded Cells qualification runs performed at the Savannah River National Laboratory (SRNL). SB8 was initially projected to be a combination of the Tank 40 heel (Sludge Batch 7b), Tank 13, Tank 12, and the Tank 51 heel. In order to accelerate preparation of SB8, the decision was made to delay the oxalate-rich material from Tank 12 to a future sludge batch. SB8 simulant studies without Tank 12 were reported in a separate report.1 The data presented in this report will be useful when processing future sludge batches containing Tank 12. The wash endpoint target for SB8 was set at a significantly higher sodium concentration to allow acceptable glass compositions at the targeted waste loading. Four non-coupled tests were conducted using simulant representing Tank 40 at 110-146% of the Koopman Minimum Acid requirement. Hydrogen was generated during high acid stoichiometry (146% acid) SRAT testing up to 31% of the DWPF hydrogen limit. SME hydrogen generation reached 48% of of the DWPF limit for the high acid run. Two non-coupled tests were conducted using simulant representing Tank 51 at 110-146% of the Koopman Minimum Acid requirement. Hydrogen was generated during high acid stoichiometry SRAT testing up to 16% of the DWPF limit. SME hydrogen generation reached 49% of the DWPF limit for hydrogen in the SME for the high acid run. Simulant processing was successful using previously established antifoam addition strategy. Foaming during formic acid addition was not observed in any of the runs. Nitrite was destroyed in all runs and no N2O was detected during SME processing. Mercury behavior was consistent with that seen in previous SRAT runs. Mercury was stripped below the DWPF limit on 0.8 wt% for all runs. Rheology yield stress fell within or below the design basis of 1-5 Pa. The low acid Tank 40 run (106% acid stoichiometry) had the highest yield stress at 3.78 Pa.

  4. Pulling of 3 mm diameter AlSb rods by micro-pulling down method

    E-Print Network [OSTI]

    Bourret-Courchesne Ph.D., Edith

    2009-01-01

    Sb) and AlSb crystal zirconia were expected as crucibles,crucible shape with zirconia. Page 3/10 Fig 1 : vitreous

  5. K2CsSb Cathode Development

    SciTech Connect (OSTI)

    Smedley,J.; Rao, T.; Wang, E.

    2008-10-01

    K{sub 2}CsSb is an attractive photocathode for high current applications. With a quantum efficiency of >4% at 532nm and >10% at 355nm, it is the only cathode to have demonstrated an average current of 35mA in an accelerator environment We describe ongoing cathode development work. for the energy recovery linac being constructed at BNL Several cathodes have been created on both copper and stainless steel substrates, and their spatial uniformity and spectral response have been characterized. Preliminary lifetime measurements have been performed at high average current densities (>1 mA/mm{sup 2}).

  6. Fragile structural transition in Mo3Sb7

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yan, Jiaqiang -Q.; McGuire, Michael A; May, Andrew F; Parker, David S.; Mandrus, D. G.; Sales, Brian C.

    2015-08-10

    Mo3Sb7 single crystals lightly doped with Cr, Ru, or Te are studied in order to explore the interplay between superconductivity, magnetism, and the cubic-tetragonal structural transition. The structural transition at 53 K is extremely sensitive to Ru or Te substitution which introduces additional electrons, but robust against Cr substitution. We observed no sign of a structural transition in superconducting Mo2.91Ru0.09Sb7 and Mo3Sb6.975Te0.025. In contrast, 3 at.% Cr doping only slightly suppresses the structural transition to 48 K while leaving no trace of superconductivity above 1.8 K. Analysis of magnetic properties suggests that the interdimer interaction in Mo3Sb7 is near amore »critical value and essential for the structural transition. Futhermore, all dopants suppress the superconductivity of Mo3Sb7. The tetragonal structure is not necessary for superconductivity.« less

  7. Transition threshold in Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses

    SciTech Connect (OSTI)

    Wei, Wen-Hou [Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Fang, Liang, E-mail: lfang@cqu.edu.cn [Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Shen, Xiang [Laboratory of Infrared Material and Devices, Advanced Technology Research Institute, Ningbo University, Ningbo 315211 (China); Wang, Rong-Ping [Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2014-03-21

    Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses with Ge content from 7.5 to 32.5?at.?% have been prepared by melt-quench technique, and the physical parameters including glass transition temperature (T{sub g}), density (?), compactness (C), shear elastic moduli (C{sub s}), compression elastic moduli (C{sub c}), refractive index (n), and optical bandgap (E{sub g}) have been investigated. While all these physical parameters show threshold behavior in the glass with a chemically stoichiometric composition. Raman spectra analysis also indicates that, with increasing Ge content, Se-chains or rings gradually disappear until all Se-atoms are consumed in the glass with a chemically stoichiometric composition. With further increasing Ge content, homopolar Ge-Ge and Sb-Sb bonds are formed and the chemical order in the glasses is violated. The threshold behavior of the physical properties in the Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses can be traced to demixing of networks above the chemically stoichiometric composition.

  8. Astrometric orbits of SB9 stars

    E-Print Network [OSTI]

    Jancart, S; Babusiaux, C; Pourbaix, D

    2005-01-01

    Hipparcos Intermediate Astrometric Data (IAD) have been used to derive astrometric orbital elements for spectroscopic binaries from the newly released Ninth Catalogue of Spectroscopic Binary Orbits (SB9). Among the 1374 binaries from SB9 which have an HIP entry, 282 have detectable orbital astrometric motion (at the 5% significance level). Among those, only 70 have astrometric orbital elements that are reliably determined (according to specific statistical tests discussed in the paper), and for the first time for 20 systems, representing a 10% increase relative to the 235 DMSA/O systems already present in the Hipparcos Double and Multiple Systems Annex. The detection of the astrometric orbital motion when the Hipparcos IAD are supplemented by the spectroscopic orbital elements is close to 100% for binaries with only one visible component, provided that the period is in the 50 - 1000 d range and the parallax is larger than 5 mas. This result is an interesting testbed to guide the choice of algorithms and stati...

  9. Optical analyzer

    DOE Patents [OSTI]

    Hansen, A.D.

    1987-09-28

    An optical analyzer wherein a sample of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter is placed in a combustion tube, and light from a light source is passed through the sample. The temperature of the sample is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample is detected as the temperature is raised. A data processor, differentiator and a two pen recorder provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample. These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample. Additional information is obtained by repeating the run in different atmospheres and/or different rates or heating with other samples of the same particulate material collected on other filters. 7 figs.

  10. Formation of MnSb during the growth of MnSi layers in the presence of an Sb flux

    E-Print Network [OSTI]

    Pennycook, Steve

    Epitaxial growth of silicide layers on Si substrates has attracted much attention due to their technologicalFormation of MnSb during the growth of MnSi layers in the presence of an Sb flux K. Matsuda, Y have been performed to elucidate the growth mechanism. The MnSi layer was grown by reactive deposition

  11. The middle Martian atmosphere

    SciTech Connect (OSTI)

    Jaquin, R.F.

    1989-01-01

    Profiles of scattered light above the planetary limb from 116 Viking Orbiter images are used to constrain the temporal and spatial behavior of aerosols suspended in the Martian atmosphere. The data cover a wide range of seasons, locations, and viewing geometry, providing information about the aerosol optical properties and vertical distribution. The typical atmospheric column contains one or more discrete, optically thin, ice-like haze layers between 30 and 90 km elevation whose composition is inferred to be water ice. Below the detached hazes, a continuous haze, interpreted to have a large dust component, extends from as much as 50 km to the surface. The haze distribution exhibits an annual variation that reflects a seasonally driven circulation in the middle atmosphere. The potential role of stationary gravity waves in modifying the middle atmosphere circulation is explored using a linear theory applied to a realistic Martian environment. Martian topography derived from radar observations is decomposed into Fourier harmonics and used to linearly superpose gravity waves arising from each component. The larger amplitude topography on Mars combined with the absence of extended regions of smooth topography like oceans generates larger wave amplitudes than on the Earth. The circulation of the middle atmosphere is examined using a two-dimensional, linearized, axisymmetric model successfully employed in the study of the terrestrial mesosphere. Illustrations of temperature and wind speeds are presented for the southern summer solstice and southern spring equinox.

  12. Analysis of the Application of the Optical Method to the Measurements of the Water Vapor Content in the Atmosphere. I. Basic Concepts

    E-Print Network [OSTI]

    Galkin, V D; Alekseeva, G A; Berger, F -H; Leiterer, U; Naebert, T; Nikanorova, I N; Novikov, V V; Pakhomov, V P; Sal'nikov, I B

    2010-01-01

    We retrieved the total content of the atmospheric water vapor from extensive sets of photometric data obtained since 1995 at Lindenberg Meteorological Observatory with star and sun photometers. Different methods of determination of the empirical parameters that are necessary for the retrieval are discussed. The instruments were independently calibrated using laboratory measurements made at Pulkovo Observatory with the VKM-100 multi-pass vacuum cell. The empirical parameters were also calculated by the simulation of the atmospheric absorption by water vapor, using the MODRAN-4 program package for different model atmospheres. The results are compared to those presented in the literature, obtained with different instruments and methods of the retrieval. The accuracy of the empirical parameters used for the power approximation that links the water vapor content with the observed absorption is analyzed. Currently, the calibration and measurement errors yield the uncertainty of about 10% in the total column water v...

  13. Using radiative transfer models to study the atmospheric water vapor content and to eliminate telluric lines from high-resolution optical spectra

    E-Print Network [OSTI]

    Gardini, A; Pérez, E; Quesada, J A; Funke, B

    2012-01-01

    The Radiative Transfer Model (RTM) and the retrieval algorithm, incorporated in the SCIATRAN 2.2 software package developed at the Institute of Remote Sensing/Institute of Enviromental Physics of Bremen University (Germany), allows to simulate, among other things, radiance/irradiance spectra in the 2400-24 000 {\\AA} range. In this work we present applications of RTM to two case studies. In the first case the RTM was used to simulate direct solar irradiance spectra, with different water vapor amounts, for the study of the water vapor content in the atmosphere above Sierra Nevada Observatory. Simulated spectra were compared with those measured with a spectrometer operating in the 8000-10 000 {\\AA} range. In the second case the RTM was used to generate telluric model spectra to subtract the atmospheric contribution and correct high-resolution stellar spectra from atmospheric water vapor and oxygen lines. The results of both studies are discussed.

  14. Anisotropic giant magnetoresistance in NbSb?

    SciTech Connect (OSTI)

    Wang, Kefeng; Graf, D.; Li, Lijun; Wang, Limin; Petrovic, C.

    2014-12-05

    We report large transverse magnetoreistance (the magnetoresistant ratio ~ 1.3 × 10?% in 2 K and 9 T field, and 4.3 × 10?% in 0.4 K and 32 T field, without saturation) and field-induced metal semiconductor-like transition in NbSb?. Magnetoresistance is significantly suppressed but the metal-semiconductor-like transition persists when the current is along the ac-plane. The sign reversal of the Hall resistivity and Seebeck coefficient in the field, plus the electronic structure reveal the coexistence of a small number of holes with very high mobility and a large number of electrons with low mobility. The large MR is attributed to the change of the Fermi surface induced by the magnetic field in addition to the high mobility metal.

  15. Anisotropic giant magnetoresistance in NbSb?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Kefeng; Graf, D.; Li, Lijun; Wang, Limin; Petrovic, C.

    2014-12-05

    We report large transverse magnetoreistance (the magnetoresistant ratio ~ 1.3 × 10?% in 2 K and 9 T field, and 4.3 × 10?% in 0.4 K and 32 T field, without saturation) and field-induced metal semiconductor-like transition in NbSb?. Magnetoresistance is significantly suppressed but the metal-semiconductor-like transition persists when the current is along the ac-plane. The sign reversal of the Hall resistivity and Seebeck coefficient in the field, plus the electronic structure reveal the coexistence of a small number of holes with very high mobility and a large number of electrons with low mobility. The large MR is attributed tomore »the change of the Fermi surface induced by the magnetic field in addition to the high mobility metal.« less

  16. SB9: The Ninth Catalogue of Spectroscopic Binary Orbits

    E-Print Network [OSTI]

    Pourbaix, D; Batten, A H; Fekel, F C; Hartkopf, W I; Levato, H; Morrell, N I; Torres, G; Udry, S

    2004-01-01

    The Ninth Catalogue of Spectroscopic Binary Orbits (http://sb9.astro.ulb.ac.be) continues the series of compilations of spectroscopic orbits carried out over the past 35 years by Batten and collaborators. As of 2004 May 1st, the new Catalogue holds orbits for 2,386 systems. Some essential differences between this catalogue and its predecessors are outlined and three straightforward applications are presented: (1) Completeness assessment: period distribution of SB1s and SB2s; (2) Shortest periods across the H-R diagram; (3) Period-eccentricity relation.

  17. SB9: The Ninth Catalogue of Spectroscopic Binary Orbits

    E-Print Network [OSTI]

    D. Pourbaix; A. A. Tokovinin; A. H. Batten; F. C. Fekel; W. I. Hartkopf; H. Levato; N. I. Morrell; G. Torres; S. Udry

    2004-06-25

    The Ninth Catalogue of Spectroscopic Binary Orbits (http://sb9.astro.ulb.ac.be) continues the series of compilations of spectroscopic orbits carried out over the past 35 years by Batten and collaborators. As of 2004 May 1st, the new Catalogue holds orbits for 2,386 systems. Some essential differences between this catalogue and its predecessors are outlined and three straightforward applications are presented: (1) Completeness assessment: period distribution of SB1s and SB2s; (2) Shortest periods across the H-R diagram; (3) Period-eccentricity relation.

  18. Atmospheric Neutrinos

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2006-12-11

    This paper is a brief overview of the theory and experimental data of atmospheric neutrino production at the fiftieth anniversary of the experimental discovery of neutrinos.

  19. Measuring Nighttime Atmospheric Opacity Using Images From the Mars Exploration Rovers 

    E-Print Network [OSTI]

    Bean, Keri M

    2012-07-11

    Atmospheric opacity, otherwise known as optical depth, is the measurement of the amount of radiation reaching the surface through the atmosphere. The spatial and temporal patterns in optical depth tell us about the aerosol and cloud cycles...

  20. The Laboratory Complex for the Calibration of Photometers Using the Optical Method for Determination of the Water Vapor Content in the Earth Atmosphere

    E-Print Network [OSTI]

    Galkin, V D; Nikanorova, I N; Leiterer, U; Niebert, T; Alekseeva, G A; Novikov, V V; Ilyin, G N; Pakhomov, V P

    2010-01-01

    We describe the laboratory complex for the calibration of photometers that are used in weather service to measure the water vapor content in the Earth atmosphere. The complex was built up in Pulkovo Observatory and developed within the framework of collaboration between Pulkovo Observatory and Lindenberg Meteorological Observatory (Meteorologisches Observatorium Lindenberg - Richard-A{\\ss}mann-Observatorium, Lindenberg, Germany). It is used to obtain calibration dependences for individual devices, and also to develop and compare various methods of construction of calibration dependences. These techniques are based on direct calibration of the photometers, on the use of spectral laboratory transmission functions for water vapor, on calculation methods using spectroscopical databases for individual lines. We hope that when the parameters of the equipment are taken into account in detail and new results for the absorptive power of water vapor are used, the accuracy of determination of the water vapor content in ...

  1. TANK 40 FINAL SB6 CHEMICAL CHARACTERIZATION RESULTS

    SciTech Connect (OSTI)

    Bannochie, C.

    2010-08-13

    A sample of Sludge Batch 6 (SB6) was taken from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS), and a portion of the sample was designated for SB6 processing studies. The SB6 WAPS sample was also analyzed for chemical composition including noble metals and fissile composition, and these results are reported here. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to DWPF as SB6. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB6 sample was transferred from the shipping container into a 4-L high density polyethylene vessel and solids were allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 485 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples.

  2. Impact of thermal annealing on bulk InGaAsSbN materials grown by metalorganic vapor phase epitaxy

    SciTech Connect (OSTI)

    Kim, T. W.; Mawst, L. J.; Kim, K.; Lee, J. J.; Kuech, T. F.; Wells, N. P.; LaLumondiere, S. D.; Sin, Y.; Lotshaw, W. T.; Moss, S. C.

    2014-02-03

    Two different thermal annealing techniques (rapid thermal annealing (RTA) and in-situ post-growth annealing in the metalorganic vapor phase epitaxy (MOVPE) chamber) were employed to investigate their impact on the optical characteristics of double-heterostructures (DH) of InGaAsSbN/GaAs and on the performance of single-junction solar cell structures, all grown by MOVPE. We find that an optimized RTA procedure leads to a similar improvement in the photoluminescence (PL) intensity compared with material employing a multi-step optimized anneal within the MOVPE reactor. Time-resolved photoluminescence techniques at low temperature (LT) and room temperature (RT) were performed to characterize the carrier dynamics in bulk InGaAsSbN layers. Room temperature carrier lifetimes were found to be similar for both annealing methods, although the LT-PL (16?K) measurements of the MOVPE-annealed sample found longer lifetimes than the RTA-annealed sample (680?ps vs. 260?ps) for the PL measurement energy of 1.24?eV. InGaAsSbN-based single junction solar cells processed with the optimized RTA procedure exhibited an enhancement of the electrical performance, such as improvements in open circuit voltage, short circuit current, fill factor, and efficiency over solar cells subjected to the in-situ MOVPE annealing technique.

  3. Evaluation of the two-photon absorption characteristics of GaSb/GaAs quantum rings

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R.; Carrington, P. J.; Krier, A.

    2014-07-28

    The optical parameters describing the sub-bandgap response of GaSb/GaAs quantum rings solar cells have been obtained from photocurrent measurements using a modulated pseudo-monochromatic light source in combination with a second, continuous photo-filling source. By controlling the charge state of the quantum rings, the photoemission cross-sections describing the two-photon sub-bandgap transitions could be determined independently. Temperature dependent photo-response measurements also revealed that the barrier for thermal hole emission from the quantum rings is significantly below the quantum ring localisation energy. The temperature dependence of the sub-bandgap photo-response of the solar cell is also described in terms of the photo- and thermal-emission characteristics of the quantum rings.

  4. Photocapacitance study of type-II GaSb/GaAs quantum ring solar cells

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R.; Carrington, P. J.; Krier, A.

    2014-01-07

    In this study, the density of states associated with the localization of holes in GaSb/GaAs quantum rings are determined by the energy selective charging of the quantum ring distribution. The authors show, using conventional photocapacitance measurements, that the excess charge accumulated within the type-II nanostructures increases with increasing excitation energies for photon energies above 0.9?eV. Optical excitation between the localized hole states and the conduction band is therefore not limited to the ?(k?=?0) point, with pseudo-monochromatic light charging all states lying within the photon energy selected. The energy distribution of the quantum ring states could consequently be accurately related from the excitation dependence of the integrated photocapacitance. The resulting band of localized hole states is shown to be well described by a narrow distribution centered 407?meV above the GaAs valence band maximum.

  5. Ultrafast terahertz-induced response of GeSbTe phase-change materials

    SciTech Connect (OSTI)

    Shu, Michael J.; Zalden, Peter; Chen, Frank; Weems, Ben; Chatzakis, Ioannis; Xiong, Feng; Jeyasingh, Rakesh; Pop, Eric; Philip Wong, H.-S.; Hoffmann, Matthias C.; Wuttig, Matthias; Lindenberg, Aaron M.

    2014-06-23

    The time-resolved ultrafast electric field-driven response of crystalline and amorphous GeSbTe films has been measured all-optically, pumping with single-cycle terahertz pulses as a means of biasing phase-change materials on a sub-picosecond time-scale. Utilizing the near-band-gap transmission as a probe of the electronic and structural response below the switching threshold, we observe a field-induced heating of the carrier system and resolve the picosecond-time-scale energy relaxation processes and their dependence on the sample annealing condition in the crystalline phase. In the amorphous phase, an instantaneous electroabsorption response is observed, quadratic in the terahertz field, followed by field-driven lattice heating, with Ohmic behavior up to 200?kV/cm.

  6. Hydrogen passivation of Se and Te in AlSb M. D. McCluskey and E. E. Haller

    E-Print Network [OSTI]

    McCluskey, Matthew

    Hydrogen passivation of Se and Te in AlSb M. D. McCluskey and E. E. Haller Lawrence Berkeley observed local vibrational modes LVM's arising from DX-hydrogen complex in AlSb. Hydrogen was diffused into bulk AlSb:Se and AlSb:Te by annealing in sealed quartz ampoules with either hydrogen gas or methanol CH

  7. TANK 40 FINAL SB7B CHEMICAL CHARACTERIZATION RESULTS

    SciTech Connect (OSTI)

    Bannochie, C.

    2012-03-15

    A sample of Sludge Batch 7b (SB7b) was taken from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). The SB7b WAPS sample was also analyzed for chemical composition including noble metals and fissile constituents, and these results are reported here. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to the Defense Waste Processing Facility (DWPF) as SB7b. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB7b sample was transferred from the shipping container into a 4-L high density polyethylene bottle and solids were allowed to settle over the weekend. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 558 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon{reg_sign} vessels and four with NaOH/Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Two Analytical Reference Glass - 1 (ARG-1) standards were digested along with a blank for each preparation. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma - atomic emission spectroscopy (ICP-AES) analysis, inductively coupled plasma - mass spectrometry (ICP-MS) analysis, atomic absorption spectroscopy (AA) for As and Se, and cold vapor atomic absorption spectroscopy (CV-AA) for Hg. Equivalent dilutions of the alkali fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB7b supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES, ion chromatography (IC), total base/free OH{sup -}/other base, total inorganic carbon/total organic carbon (TIC/TOC) analyses, and Cs-137 gamma scan. Weighted dilutions of slurry were submitted for IC, TIC/TOC, and total base/free OH{sup -}/other base analyses. Activities for U-233, U-235, and Pu-239 were determined from the ICP-MS data for the aqua regia digestions of the Tank 40 WAPS slurry using the specific activity of each isotope. The Pu-241 value was determined from a Pu-238/-241 method developed by SRNL AD and previously described. The following conclusions were drawn from the analytical results reported here: (1) The ratios of the major elements for the SB7b WAPS sample are different from those measured for the SB7a WAPS sample. There is less Al and Mn relative to Fe than the previous sludge batch. (2) The elemental composition of this sample and the analyses conducted here are reasonable and consistent with DWPF batch data measurements in light of DWPF pre-sample concentration and SRAT product heel contributions to the DWPF SRAT receipt analyses. The element ratios for Al/Fe, Ca/Fe, Mn/Fe, and U/Fe agree within 10% between this work and the DWPF Sludge Receipt and Adjustment Tank (SRAT) receipt analyses. (3) Sulfur in the SB7b WAPS sample is 82% soluble, slightly less than results reported for SB3, SB4, and SB6 samples but unlike the 50% insoluble sulfur observed in the SB5 WAPS sample. In addition, 23% of the soluble sulfur is not present as sulfate in SB7b. (4) The average activities of the fissile isotopes of interest in the SB7b WAPS sample are (in {mu}Ci/g of total dried solids): 4.22E-02 U-233, 6.12E-04 U-235, 1.08E+01 Pu-239, and 5.09E+01 Pu-241. The full radionuclide composition will be reported in a future document. (5) The fission product noble metal and Ag concentrations appear to have largely peaked in previous DWPF sludge batches, with the exception of Ru, which still shows a slight increase in SB7b.

  8. Magnetic properties of MnSb inclusions formed in GaSb matrix directly during molecular beam epitaxial growth

    SciTech Connect (OSTI)

    Lawniczak-Jablonska, Krystyna; Wolska, Anna; Klepka, Marcin T.; Kret, Slawomir; Kurowska, Boguslawa; Kowalski, Bogdan J.; Twardowski, Andrzej; Wasik, Dariusz; Kwiatkowski, Adam; Sadowski, Janusz

    2011-04-01

    Despite of intensive search for the proper semiconductor base materials for spintronic devices working at room temperature no appropriate material based on ferromagnetic semiconductors has been found so far. We demonstrate that the phase segregated system with MnSb hexagonal inclusions inside the GaSb matrix, formed directly during the molecular beam epitaxial growth reveals the ferromagnetic properties at room temperature and is a good candidate for exploitation in spintronics. Furthermore, the MnSb inclusions with only one crystalline structure were identified in this GaMn:MnSb granular material. The SQUID magnetometry confirmed that this material exhibits ferromagnetic like behavior starting from helium up to room temperature. Moreover, the magnetic anisotropy was found which was present also at room temperature, and it was proved that by choosing a proper substrate it is possible to control the direction of easy axis of inclusions' magnetization moment between in-plane and out-of-plane; the latter is important in view of potential applications in spintronic devices.

  9. Eight-band k·p modeling of InAs/InGaAsSb type-II W-design quantum well structures for interband cascade lasers emitting in a broad range of mid infrared

    SciTech Connect (OSTI)

    Ryczko, K.; S?k, G.; Misiewicz, J. [Institute of Physics, Wroc?aw University of Technology, Wybrze?e Wyspia?skiego 27, 50-370 Wroc?aw (Poland)

    2013-12-14

    Band structure properties of the type-II W-design AlSb/InAs/GaIn(As)Sb/InAs/AlSb quantum wells have been investigated theoretically in a systematic manner and with respect to their use in the active region of interband cascade laser for a broad range of emission in mid infrared between below 3 to beyond 10??m. Eight-band k·p approach has been utilized to calculate the electronic subbands. The fundamental optical transition energy and the corresponding oscillator strength have been determined in function of the thickness of InAs and GaIn(As)Sb layers and the composition of the latter. There have been considered active structures on two types of relevant substrates, GaSb and InAs, introducing slightly modified strain conditions. Additionally, the effect of external electric field has been taken into account to simulate the conditions occurring in the operational devices. The results show that introducing arsenic as fourth element into the valence band well of the type-II W-design system, and then altering its composition, can efficiently enhance the transition oscillator strength and allow additionally increasing the emission wavelength, which makes this solution prospective for improved performance and long wavelength interband cascade lasers.

  10. Active Optics in Modern, Large Optical Telescopes

    E-Print Network [OSTI]

    Lothar Noethe

    2001-11-07

    Active optics is defined as the control of the shape and the alignment of the components of an optical system at low temporal frequencies. For modern large telescopes with flexible monolithic or segmented primary mirrors and also flexible structures this technique is indispensable to reach a performance which is either diffraction limited for an operation in space or limited by the atmosphere for an operation on the ground. This article first describes the theory of active optics, both of the wavefront analysis and the correction mechanisms, then the design of three representative active optics systems, two in telescopes of the four and eight meter class with meniscus mirrors and one in a telescope with a segmented primary mirror, and, finally, presents practical experience with these active optics systems.

  11. Structural transition and amorphization in compressed ? - Sb 2 O 3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhao, Zhao; Zeng, Qiaoshi; Zhang, Haijun; Wang, Shibing; Hirai, Shigeto; Zeng, Zhidan; Mao, Wendy L.

    2015-05-27

    Sb?O?-based materials are of broad interest in materials science and industry. High-pressure study using diamond anvil cells shows promise in obtaining new crystal and electronic structures different from their pristine states. Here, we conducted in situ angle dispersive synchrotron x-ray-diffraction and Raman spectroscopy experiments on ?-Sb?O? up to 50 GPa with neon as the pressure transmitting medium. A first-order structural transition was observed in between 15 and 20 GPa, where the cubic phase I gradually transformed into a layered tetragonal phase II through structural distortion and symmetry breaking. To explain the dramatic changes in sample color and transparency, we performedmore »first-principles calculations to track the evolution of its density of states and electronic structure under pressure. At higher pressure, a sluggish amorphization was observed. Our results highlight the structural connections among the sesquioxides, where the lone electron pair plays an important role in determining the local structures.« less

  12. Precision Determination of Atmospheric Extinction at Optical...

    Office of Scientific and Technical Information (OSTI)

    PanSTARRS, and the Large Synoptic Survey Telescope, require calibration of broadband photometry that is stable in time and uniform over the sky to precisions of a per cent or...

  13. PRECISION DETERMINATION OF ATMOSPHERIC EXTINCTION AT OPTICAL...

    Office of Scientific and Technical Information (OSTI)

    Stephane 3 ; Claver, Chuck ; Saha, Abhijit 4 ; Ivezic, Zeljko ; Jones, Lynne 5 ; Smith, Allyn 6 ; Smith, R. Chris 7 ; Stubbs, Christopher W., E-mail:...

  14. Free-space optical networks : fade and interference mitigation and network congestion control

    E-Print Network [OSTI]

    Lee, Etty J. (Etty Joanne)

    2010-01-01

    Optical communication through the atmospheric channel is commonly known as free-space optical (FSO) communication. When communicating through a clear FSO channel, not only is there atmospheric turbulence which results in ...

  15. Comparative analysis of hole transport in compressively strained InSb and Ge quantum well heterostructures

    SciTech Connect (OSTI)

    Agrawal, Ashish; Barth, Michael; Madan, Himanshu; Datta, Suman [Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Lee, Yi-Jing; Lin, You-Ru; Wu, Cheng-Hsien; Ko, Chih-Hsin; Wann, Clement H. [Taiwan Semiconductor Manufacturing Company, Hsinchu 30078, Taiwan (China); Loubychev, Dmitri; Liu, Amy; Fastenau, Joel [IQE, Inc., Bethlehem, Pennsylvania 18015 (United States); Lindemuth, Jeff [Lake Shore Cryotronics, Westerville, Ohio 43082 (United States)

    2014-08-04

    Compressively strained InSb (s-InSb) and Ge (s-Ge) quantum well heterostructures are experimentally studied, with emphasis on understanding and comparing hole transport in these two-dimensional confined heterostructures. Magnetotransport measurements and bandstructure calculations indicate 2.5× lower effective mass for s-InSb compared to s-Ge quantum well at 1.9?×?10{sup 12}?cm{sup –2}. Advantage of strain-induced m* reduction is negated by higher phonon scattering, degrading hole transport at room temperature in s-InSb quantum well compared to s-Ge heterostructure. Consequently, effective injection velocity is superior in s-Ge compared to s-InSb. These results suggest s-Ge quantum well heterostructure is more favorable and promising p-channel candidate compared to s-InSb for future technology node.

  16. Ab initio study of structural, electronic, magnetic alloys: XTiSb (X = Co, Ni and Fe)

    SciTech Connect (OSTI)

    Ibrir, M. Berri, S.; Lakel, S.; Alleg, S.; Bensalem, R.

    2015-03-30

    Structural, electronic and magnetic properties of three semi-Heusler compounds of CoTiSb, NiTiSb and FeTiSb were calculated by the method (FP-LAPW) which is based on the DFT code WIEN2k. We used the generalized gradient approximation (GGA (06)) for the term of the potential exchange and correlation (XC) to calculate structural properties, electronic properties and magnetic properties. Structural properties obtained as the lattice parameter are in good agreement with the experimental results available for the electronic and magnetic properties was that: CoTiSb is a semiconductor NiTiSb is a metal and FeTiSb is a half-metal ferromagnetic.

  17. Photoemission study of the electronic structure and charge density waves of Na?Ti?Sb?O

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tan, S. Y. [Science and Technology on Surface Physics and Chemistry Lab., Mianyang (China); Fundan Univ., Shanghai (China); Jiang, J. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China); Ye, Z. R. [Fundan Univ., Shanghai (China); Niu, X. H. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China); Song, Y. [Rice Univ., Houston, TX (United States); Zhang, C. L. [Rice Univ., Houston, TX (United States); Univ. of Tennessee, Knoxville, TN (United States); Dai, P. C. [Rice Univ., Houston, TX (United States); Xie, B. P. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China); Lai, X. C. [Science and Technology on Surface Physics and Chemistry Lab., Mianyang (China); Feng, D. L. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China)

    2015-04-30

    The electronic structure of Na?Ti?Sb?O single crystal is studied by photon energy and polarization dependent angle-resolved photoemission spectroscopy (ARPES). The obtained band structure and Fermi surface agree well with the band structure calculation of Na?Ti?Sb?O in the non-magnetic state, which indicates that there is no magnetic order in Na?Ti?Sb?O and the electronic correlation is weak. Polarization dependent ARPES results suggest the multi-band and multi-orbital nature of Na?Ti?Sb?O. Photon energy dependent ARPES results suggest that the electronic structure of Na?Ti?Sb?O is rather two-dimensional. Moreover, we find a density wave energy gap forms below the transition temperature and reaches 65 meV at 7 K, indicating that Na?Ti?Sb?O is likely a weakly correlated CDW material in the strong electron-phonon interaction regime. (author)

  18. Photoemission study of the electronic structure and charge density waves of Na?Ti?Sb?O

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tan, S. Y.; Jiang, J.; Ye, Z. R.; Niu, X. H.; Song, Y.; Zhang, C. L.; Dai, P. C.; Xie, B. P.; Lai, X. C.; Feng, D. L.

    2015-04-30

    The electronic structure of Na?Ti?Sb?O single crystal is studied by photon energy and polarization dependent angle-resolved photoemission spectroscopy (ARPES). The obtained band structure and Fermi surface agree well with the band structure calculation of Na?Ti?Sb?O in the non-magnetic state, which indicates that there is no magnetic order in Na?Ti?Sb?O and the electronic correlation is weak. Polarization dependent ARPES results suggest the multi-band and multi-orbital nature of Na?Ti?Sb?O. Photon energy dependent ARPES results suggest that the electronic structure of Na?Ti?Sb?O is rather two-dimensional. Moreover, we find a density wave energy gap forms below the transition temperature and reaches 65 meV atmore »7 K, indicating that Na?Ti?Sb?O is likely a weakly correlated CDW material in the strong electron-phonon interaction regime. (author)« less

  19. Cu2Sb thin film electrodes prepared by pulsed laser deposition f or lithium batteries

    E-Print Network [OSTI]

    Song, Seung-Wan; Reade, Ronald P.; Cairns, Elton J.; Vaughey, Jack T.; Thackeray, Michael M.; Striebel, Kathryn A.

    2003-01-01

    The Electrochemical Society (Batteries and Energy ConversionDeposition for Lithium Batteries Seung-Wan Song, a, * Ronaldrechargeable lithium batteries. Introduction Sb-containing

  20. Method of making AlInSb by metal-organic chemical vapor deposition

    DOE Patents [OSTI]

    Biefeld, Robert M. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Baucom, Kevin C. (Albuquerque, NM)

    2000-01-01

    A method for producing aluminum-indium-antimony materials by metal-organic chemical vapor deposition (MOCVD). This invention provides a method of producing Al.sub.X In.sub.1-x Sb crystalline materials by MOCVD wherein an Al source material, an In source material and an Sb source material are supplied as a gas to a heated substrate in a chamber, said Al source material, In source material, and Sb source material decomposing at least partially below 525.degree. C. to produce Al.sub.x In.sub.1-x Sb crystalline materials wherein x is greater than 0.002 and less than one.

  1. Mineral content analysis of atmospheric dust using hyperspectral information from space

    E-Print Network [OSTI]

    Kostinski, Alex

    Mineral content analysis of atmospheric dust using hyperspectral information from space A one of the world's largest sources of atmospheric mineral dust. Mineral composition optical properties, and mineral deposition to Amazon forests. In this study we examine hyperspectral

  2. Direct imaging of InSb (110)-(1x1) surface grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Mishima, T. D. [Homer L. Dodge Department of Physics and Astronomy, and Center for Semiconductor Physics in Nanostructures, University of Oklahoma, Norman, Oklahoma 73019 (United States)

    2011-10-01

    High-resolution transmission electron microscopy under a profile imaging condition (HR-profile TEM) was employed to determine the structural model for the InSb(110)-(1x1) relaxation surface grown by molecular beam epitaxy (MBE). HR-profile TEM analyses indicate that the chevron model, which is widely accepted for zinc-blende-type III-V(110)-(1x1) surfaces prepared by cleavage, is also applicable to the InSb(110)-(1x1) surface prepared under an Sb-rich MBE condition. The assignment of atomic species (In or Sb) of InSb(110)-(1x1) surfaces was confirmed based on a HR-profile TEM image that captures the connected facets of InSb(110)-(1x1) and InSb(111)B-(2x2). On the basis of the well-known atomic species of InSb(111)B-(2x2), the atomic species of the InSb(110)-(1x1) surface were deduced straightforwardly: the atoms shifted upward and downward at the topmost layer of the InSb(110)-(1x1) surface are Sb and In, respectively. The atomic arrangements of the InSb(110)-(1x1)-InSb(111)B-(2x2) facet determined by HR-profile TEM may represent the atomic arrangements of zinc-blende-type III-V(331)B surfaces.

  3. Investigation of high hole mobility In{sub 0.41}Ga{sub 0.59}Sb...

    Office of Scientific and Technical Information (OSTI)

    hole mobility Insub 0.41Gasub 0.59SbAlsub 0.91Gasub 0.09Sb quantum well structures grown by molecular beam epitaxy Citation Details In-Document Search Title:...

  4. Tank 40 Final SB7b Chemical Characterization Results

    SciTech Connect (OSTI)

    Bannochie, C. J.

    2012-11-06

    A sample of Sludge Batch 7b (SB7b) was taken from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). The SB7b WAPS sample was also analyzed for chemical composition including noble metals and fissile constituents. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB7b sample was transferred from the shipping container into a 4-L high density polyethylene bottle and solids were allowed to settle over the weekend. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 558 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon? vessels and four with NaOH/Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Two Analytical Reference Glass ? 1 (ARG-1) standards were digested along with a blank for each preparation. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma ? atomic emission spectroscopy (ICP-AES) analysis, inductively coupled plasma ? mass spectrometry (ICP-MS) analysis, atomic absorption spectroscopy (AA) for As and Se, and cold vapor atomic absorption spectroscopy (CV-AA) for Hg. Equivalent dilutions of the alkali fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB7b supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES, ion chromatography (IC), total base/free OH{sup -}/other base, total inorganic carbon/total organic carbon (TIC/TOC) analyses, and Cs-137 gamma scan. Weighted dilutions of slurry were submitted for IC, TIC/TOC, and total base/free OH-/other base analyses. Activities for U-233, U-235, and Pu-239 were determined from the ICP-MS data for the aqua regia digestions of the Tank 40 WAPS slurry using the specific activity of each isotope. The Pu-241 value was determined from a Pu-238/-241 method.

  5. SB Electronics Breaks Ground on New Factory | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo. 195 -Rob Roberts About Us Rob RobertsSelectSAE3282 August 2011SB

  6. Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3

    E-Print Network [OSTI]

    Shen, Guoyin

    Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3 P. P. Kong1 , F. Sun1,3 , L. Y induce Sb2Se3 into a topological nontrivial state. Here, we report on the discovery of superconductivity superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition

  7. Carbon acceptors and carbon-hydrogen complexes in AlSb M. D. McCluskey*

    E-Print Network [OSTI]

    McCluskey, Matthew

    Carbon acceptors and carbon-hydrogen complexes in AlSb M. D. McCluskey* Department of Physics modes LVM's arising from carbon impurities in n- and p-type AlSb. The first and second harmonics. A peak at 572.9 cm 1 is tentatively identified as the 13 C LVM. Carbon-hydrogen complexes were formed

  8. GaSb/GaAs type II quantum dot solar cells for enhanced infrared spectral response

    E-Print Network [OSTI]

    Jalali. Bahram

    into existing multijunction cells either as a means to increase the current or efficiency by using low band gapGaSb/GaAs type II quantum dot solar cells for enhanced infrared spectral response R. B infrared spectral response of GaAs-based solar cells that incorporate type II GaSb quantum dots QDs formed

  9. Interface Reactions and Electrical Characteristics of Au/GaSb Contacts

    SciTech Connect (OSTI)

    H. Ehsani; R.J. Gutmann; G.W. Charache

    2000-07-07

    The reaction of Au with GaSb occurs at a relatively low temperature (100 C). Upon annealing, a AuSb{sub 2} compound and several Au-Ga phases are produced. Phase transitions occur toward higher Ga concentration with increasing annealing temperatures. Furthermore, the depth of the contact also increases with increased annealing temperature. They found that the AuSb{sub 2} compound forms on the GaSb surface, with the compound crystal partially ordered with respect to the substrate. The transition of Schottky- to ohmic-contact behavior in Au/n-type GaSb occurs simultaneously with the formation of the AuGa compound at about a 250 C annealing temperature. This ohmic contact forms without the segregation of dopants at the metallic compound/GaSb interface. Therefore it is postulated that transition from Schottky- to ohmic-contact behavior is obtained through a series of tunneling transitions of electrons through defects in the depletion region in the Au/n-type GaSb contacts. Contact resistivities of 6-7 x 10{sup -6} {Omega}-cm{sup 2} were obtained with the annealing temperature between 300 and 350 C for 30 seconds. In Au/p-type GaSb contacts, the resistivity was independent of the annealing temperature. This suggested that the carrier transport in p-type contact dominated by thermionic emission.

  10. Effect of annealing on the properties of Sb doped ZnO thin films prepared by spray pyrolysis technique

    SciTech Connect (OSTI)

    Kumar, N. Sadananda; Bangera, Kasturi V.; Shivakumar, G. K. [Thin Films Laboratory, Department of Physics, National Institute of Technology Karnataka,Surathkal - 575025, Mangalore (India)

    2014-01-28

    Sb doped ZnO thin films have been deposited on glass substrate at 450°C using spray pyrolysis technique. The X-ray diffraction studies revealed that the as deposited films are polycrystalline in nature with (100) preferred orientation. Whereas the films annealed at 450° C for 6h show a preferential orientation along (101) direction. Crystallites size varies from 15.7 nm to 34.95 nm with annealing duration. The Scanning electron microscopic analysis shows the plane and smooth surface of the films. The optical properties of annealed films have shown a variation in the band gap between 3.37 eV and 3.19 eV. Transparency of as grown and annealed films decreases from 78 % to 65% respectively in the visible region. The electrical conductivity of the as grown film shows an increase in the electrical conductivity by one order of magnitude with increase in the annealing duration.

  11. Band offsets determination and interfacial chemical properties of the Al2O3/GaSb system

    E-Print Network [OSTI]

    Yener, Aylin

    of a high quality dielectric/substrate interface. Native oxides of III­V com- pounds lead to the formation Sb is formed at the oxide/GaSb interface, which leads to a high leakage current.8 To overcome treatment. In contrast, NH4 2S and HCl solutions inhibit the Sb oxide formation. The lowest amount of Ga

  12. Illinois SB 1987: the Clean Coal Portfolio Standard Law

    SciTech Connect (OSTI)

    NONE

    2009-01-15

    On January 12, 2009, Governor Rod Blagojevich signed SB 1987, the Clean Coal Portfolio Standard Law. The legislation establishes emission standards for new coal-fueled power plants power plants that use coal as their primary feedstock. From 2009-2015, new coal-fueled power plants must capture and store 50 percent of the carbon emissions that the facility would otherwise emit; from 2016-2017, 70 percent must be captured and stored; and after 2017, 90 percent must be captured and stored. SB 1987 also establishes a goal of having 25 percent of electricity used in the state to come from cost-effective coal-fueled power plants that capture and store carbon emissions by 2025. Illinois is the first state to establish a goal for producing electricity from coal-fueled power plants with carbon capture and storage (CCS). To support the commercial development of CCS technology, the legislation guarantees purchase agreements for the first Illinois coal facility with CCS technology, the Taylorville Energy Center (TEC); Illinois utilities are required to purchase at least 5 percent of their electricity supply from the TEC, provided that customer rates experience only modest increases. The TEC is expected to be completed in 2014 with the ability to capture and store at least 50 percent of its carbon emissions.

  13. Optical Fibers Optics and Photonics

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    Optical Fibers Optics and Photonics Dr. Palffy-Muhoray Ines Busuladzic Department of Theoretical and Applied Mathematics The University of Akron April 21, 2008 #12;Outline · History of optical fibers · What are optical fibers? · How are optical fibers made? · Light propagation through optical fibers · Application

  14. Fiber optic fluid detector

    DOE Patents [OSTI]

    Angel, S. Michael (Livermore, CA)

    1989-01-01

    Particular gases or liquids are detected with a fiber optic element (11, 11a to 11j) having a cladding or coating of a material (23, 23a to 23j) which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector (24, 24a to 24j) may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses.

  15. Fiber optic fluid detector

    DOE Patents [OSTI]

    Angel, S.M.

    1987-02-27

    Particular gases or liquids are detected with a fiber optic element having a cladding or coating of a material which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses. 10 figs.

  16. Pressure dependence of donor excitation spectra in AlSb

    SciTech Connect (OSTI)

    Hsu, L.; McCluskey, M.D.; Haller, E.E.

    2002-01-16

    We have investigated the behavior of ground to bound excited-state electronic transitions of Se and Te donors in AlSb as a function of hydrostatic pressure. Using broadband far-infrared Fourier transform spectroscopy, we observe qualitatively different behaviors of the electronic transition energies of the two donors. While the pressure derivative of the Te transition energy is small and constant, as might be expected for a shallow donor, the pressure derivatives of the Se transition energies are quadratic and large at low pressures, indicating that Se is actually a deep donor. In addition, at pressures between 30 and 50 kbar, we observe evidence of an anti-crossing between one of the selenium electronic transitions and a two-phonon mode.

  17. DWPF SIMULANT CPC STUDIES FOR SB7B

    SciTech Connect (OSTI)

    Koopman, D.

    2011-11-01

    Lab-scale DWPF simulations of Sludge Batch 7b (SB7b) processing were performed. Testing was performed at the Savannah River National Laboratory - Aiken County Technology Laboratory (SRNL-ACTL). The primary goal of the simulations was to define a likely operating window for acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT). In addition, the testing established conditions for the SRNL Shielded Cells qualification simulation of SB7b-Tank 40 blend, supported validation of the current glass redox model, and validated the coupled process flowsheet at the nominal acid stoichiometry. An acid window of 105-140% by the Koopman minimum acid (KMA) equation (107-142% DWPF Hsu equation) worked for the sludge-only flowsheet. Nitrite was present in the SRAT product for the 105% KMA run at 366 mg/kg, while SME cycle hydrogen reached 94% of the DWPF Slurry Mix Evaporator (SME) cycle limit in the 140% KMA run. The window was determined for sludge with added caustic (0.28M additional base, or roughly 12,000 gallons 50% NaOH to 820,000 gallons waste slurry). A suitable processing window appears to be 107-130% DWPF acid equation for sludge-only processing allowing some conservatism for the mapping of lab-scale simulant data to full-scale real waste processing including potentially non-conservative noble metal and mercury concentrations. This window should be usable with or without the addition of up to 7,000 gallons of caustic to the batch. The window could potentially be wider if caustic is not added to SB7b. It is recommended that DWPF begin processing SB7b at 115% stoichiometry using the current DWPF equation. The factor could be increased if necessary, but changes should be made with caution and in small increments. DWPF should not concentrate past 48 wt.% total solids in the SME cycle if moderate hydrogen generation is occurring simultaneously. The coupled flowsheet simulation made more hydrogen in the SRAT and SME cycles than the sludge-only run with the same acid stoichiometric factor. The slow acid addition in MCU seemed to alter the reactions that consumed the small excess acid present such that hydrogen generation was promoted relative to sludge-only processing. The coupled test reached higher wt.% total solids, and this likely contributed to the SME cycle hydrogen limit being exceeded at 110% KMA. It is clear from the trends in the SME processing GC data, however, that the frit slurry formic acid contributed to driving the hydrogen generation rate above the SME cycle limit. Hydrogen generation rates after the second frit addition generally exceeded those after the first frit addition. SRAT formate loss increased with increasing acid stoichiometry (15% to 35%). A substantial nitrate gain which was observed to have occurred after acid addition (and nitrite destruction) was reversed to a net nitrate loss in runs with higher acid stoichiometry (nitrate in SRAT product less than sum of sludge nitrate and added nitric acid). Increased ammonium ion formation was also indicated in the runs with nitrate loss. Oxalate loss on the order 20% was indicated in three of the four acid stoichiometry runs and in the coupled flowsheet run. The minimum acid stoichiometry run had no indicated loss. The losses were of the same order as the official analytical uncertainty of the oxalate concentration measurement, but were not randomly distributed about zero loss, so some actual loss was likely occurring. Based on the entire set of SB7b test data, it is recommended that DWPF avoid concentrating additional sludge solids in single SRAT batches to limit the concentrations of noble metals to SB7a processing levels (on a grams noble metal per SRAT batch basis). It is also recommended that DWPF drop the formic acid addition that accompanies the process frit 418 additions, since SME cycle data showed considerable catalytic activity for hydrogen generation from this additional acid (about 5% increase in stoichiometry occurred from the frit formic acid). Frit 418 also does not appear to need formic acid addition to prevent gel formation in

  18. Atmospheric Transport of Radionuclides

    SciTech Connect (OSTI)

    Crawford, T.V.

    2003-03-03

    The purpose of atmospheric transport and diffusion calculations is to provide estimates of concentration and surface deposition from routine and accidental releases of pollutants to the atmosphere. This paper discusses this topic.

  19. Atmospheric chemistry and global change

    E-Print Network [OSTI]

    Prather, MJ

    1999-01-01

    and particles. Thus Atmospheric Chemistry and Global Changethe future of atmospheric chemistry. BROWSINGS Tornadothe complexity of atmospheric chemistry well, but trips a

  20. Effects of Ge replacement in GeTe by [Ag+Sb] on thermoelectric...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in GeTe by Ag+Sb on thermoelectric properties and NMR spectra Requirements for student: general physics and chemistry courses, and desire to work in experimental laboratory. This...

  1. Grain refinement and texture development of cast bi90sb10 alloy via severe plastic deformation 

    E-Print Network [OSTI]

    Im, Jae-taek

    2009-05-15

    The purpose of this work was to study learn about grain refinement mechanisms and texture development in cast n-type Bi90Sb10 alloy caused by severe plastic deformation. The practical objective is to produce a fine grained ...

  2. Pulling of 3 mm diameter AlSb rods by micro-pulling down method

    E-Print Network [OSTI]

    Bourret-Courchesne Ph.D., Edith

    2009-01-01

    SUBCONTRACT #6836278 Pulling of 3 mm diameter AlSb rods by1 cm long, and at least 3 mm in diameter. provided by LBNL.l Crucible Power/T° Speed (mm/min) Seed Results Crucible

  3. Intense terahertz emission from molecular beam epitaxy-grown GaAs/GaSb(001)

    SciTech Connect (OSTI)

    Sadia, Cyril P.; Laganapan, Aleena Maria; Agatha Tumanguil, Mae; Estacio, Elmer; Somintac, Armando; Salvador, Arnel; Que, Christopher T.; Yamamoto, Kohji; Tani, Masahiko

    2012-12-15

    Intense terahertz (THz) electromagnetic wave emission was observed in undoped GaAs thin films deposited on (100) n-GaSb substrates via molecular beam epitaxy. GaAs/n-GaSb heterostructures were found to be viable THz sources having signal amplitude 75% that of bulk p-InAs. The GaAs films were grown by interruption method during the growth initiation and using various metamorphic buffer layers. Reciprocal space maps revealed that the GaAs epilayers are tensile relaxed. Defects at the i-GaAs/n-GaSb interface were confirmed by scanning electron microscope images. Band calculations were performed to infer the depletion region and electric field at the i-GaAs/n-GaSb and the air-GaAs interfaces. However, the resulting band calculations were found to be insufficient to explain the THz emission. The enhanced THz emission is currently attributed to a piezoelectric field induced by incoherent strain and defects.

  4. Thermoelectric properties of AgSbTe? from first-principles calculations

    SciTech Connect (OSTI)

    Rezaei, Nafiseh; Akbarzadeh, Hadi; Hashemifar, S. Javad

    2014-09-14

    The structural, electronic, and transport properties of AgSbTe? are studied by using full-relativistic first-principles electronic structure calculation and semiclassical description of transport parameters. The results indicate that, within various exchange-correlation functionals, the cubic Fd3?m and trigonal R3?m structures of AgSbTe? are more stable than two other considered structures. The computed Seebeck coefficients at different values of the band gap and carrier concentration are accurately compared with the available experimental data to speculate a band gap of about 0.1–0.35 eV for AgSbTe? compound, in agreement with our calculated electronic structure within the hybrid HSE (Heyd-Scuseria-Ernzerhof) functional. By calculating the semiclassical Seebeck coefficient, electrical conductivity, and electronic part of thermal conductivity, we present the theoretical upper limit of the thermoelectric figure of merit of AgSbTe? as a function of temperature and carrier concentration.

  5. Self-Assembled ErSb Nanostructures with Optical Applications in Infrared

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference) |Janka,Ferrara U./INFN,TaÅŸ,Superconductors (Conference)Self

  6. Solvothermal synthesis of graphene-Sb{sub 2}S{sub 3} composite and the degradation activity under visible light

    SciTech Connect (OSTI)

    Tao, Wenguang; Chang, Jiuli; Wu, Dapeng; Gao, Zhiyong; Duan, Xiaoli; Xu, Fang; Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007 ; Jiang, Kai; Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ? Graphene-Sb{sub 2}S{sub 3} composites were synthesized through a facile solvothermal method. ? Hydroxyl radicals are the main species responsible for the photodegradation activity. ? Graphene-Sb{sub 2}S{sub 3} demonstrated dramatically improved visible light degradation activity. -- Abstract: Novel graphene-Sb{sub 2}S{sub 3} (G-Sb{sub 2}S{sub 3}) composites were synthesized via a facile solvothermal method with graphene oxide (GO), SbCl{sub 3} and thiourea as the reactants. GO played an important role in controlling the size and the distribution of the formed Sb{sub 2}S{sub 3} nanoparticles on the graphene sheets with different density. Due to the negative surface charge, smaller Sb{sub 2}S{sub 3} particles size and efficient electrons transfer from Sb{sub 2}S{sub 3} to graphene, the composites demonstrated improved photodegradation activity on rhodamine B (RhB). Among these composites, the product G-Sb{sub 2}S{sub 3} 0.1, which was synthesized with the GO concentration of 0.1 mg/mL, exhibited the highest photodegradation activity owing to the considerable density of Sb{sub 2}S{sub 3} nanoparticles onto graphene sheet free of aggregation. Hydroxyl radicals (·OH) derived from conduction band (CB) electrons of Sb{sub 2}S{sub 3} is suggested to be responsible for the photodegradation of RhB. The high visible light degradation activity and the satisfactory cycling stability made the as-prepared G-Sb{sub 2}S{sub 3} 0.1 an applicable photocatalyst.

  7. Optical microspectrometer

    DOE Patents [OSTI]

    Sweatt, William C.; Christenson, Todd R.

    2004-05-25

    An optical microspectrometer comprises a grism to disperse the spectra in a line object. A single optical microspectrometer can be used to sequentially scan a planar object, such as a dye-tagged microchip. Because the optical microspectrometer is very compact, multiple optical microspectrometers can be arrayed to provide simultaneous readout across the width of the planar object The optical microspectrometer can be fabricated with lithographic process, such as deep X-ray lithography (DXRL), with as few as two perpendicular exposures.

  8. The magnetic structure of EuCu2Sb2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ryan, D. H.; Cadogan, J. M.; Anand, V. K.; Johnston, D. C.; Flacau, R.

    2015-05-06

    Antiferromagnetic ordering of EuCu2Sb2 which forms in the tetragonal CaBe2Ge2-type structure (space group P4/nmm #129) has been studied using neutron powder diffraction and 151Eu Mössbauer spectroscopy. The room temperature 151Eu isomer shift of –12.8(1) mm/s shows the Eu to be divalent, while the 151Eu hyperfine magnetic field (Bhf) reaches 28.7(2) T at 2.1 K, indicating a full Eu2+ magnetic moment. Bhf(T) follows a smooth $S=\\frac{7}{2}$ Brillouin function and yields an ordering temperature of 5.1(1) K. Refinement of the neutron diffraction data reveals a collinear A-type antiferromagnetic arrangement with the Eu moments perpendicular to the tetragonal c-axis. As a result, themore »refined Eu magnetic moment at 0.4 K is 7.08(15) ?B which is the full free-ion moment expected for the Eu2+ ion with $S=\\frac{7}{2}$ and a spectroscopic splitting factor of g = 2.« less

  9. Magnetized Atmospheres around Accreting Neutron Stars

    E-Print Network [OSTI]

    S. Zane; R. Turolla; A. Treves

    2000-02-01

    We present a detailed investigation of atmospheres around accreting neutron stars with high magnetic field ($B\\gtrsim 10^{12}$ G) and low luminosity ($L\\lesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity and emergent spectrum for a plane-parallel, pure hydrogen medium by solving the transfer equations for the normal modes coupled to the hydrostatic and energy balance equations. The hard tail found in previous investigations for accreting, non-magnetic neutron stars with comparable luminosity is suppressed and the X-ray spectrum, although still harder than a blackbody at the star effective temperature, is nearly planckian in shape. Spectra from accreting atmospheres, both with high and low fields, are found to exhibit a significant excess at optical wavelengths above the Rayleigh-Jeans tail of the X-ray continuum.

  10. Atmospheric Neutrino Fluxes

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2005-02-18

    Starting with an historical review, I summarize the status of calculations of the flux of atmospheric neutrinos and how they compare to measurements.

  11. High-power InAs/InAsSbP heterostructure leds for methane spectroscopy ({lambda} {approx} 3.3 {mu}m)

    SciTech Connect (OSTI)

    Astakhova, A. P.; Golovin, A. S.; Il'inskaya, N. D.; Kalinina, K. V.; Kizhayev, S. S., E-mail: serguie@mail.ru; Serebrennikova, O. Yu.; Stoyanov, N. D. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Horvath, Zs. J. [Hungarian Academy of Sciences, Research Institute for Technical Physics and Materials Science (Hungary); Yakovlev, Yu. P. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

    2010-02-15

    Two designs of light-emitting diodes (LEDs) based on InAsSbP/InAs/InAsSbP double hetero-structures grown by metal-organic vapor phase epitaxy on p- and n-InAs substrates have been studied. The current-voltage and electroluminescence characteristics of the LEDs are analyzed. It is shown that the LED design with a light-emitting crystal (chip) mounted with the epitaxial layer down on the LED case and emission extracted through the n-InAs substrate provides better heat removal. As a result, the spectral characteristics remain stable at increased injection currents and the quantum efficiency of radiative recombination is higher. The internal quantum efficiency of light-em itting structures with an emission wavelength {lambda} = 3.3-3.4 {mu}m is as high as 22.3%. The optical emission power of the LEDs is 140 {mu}W at a current of 1 A in the quasi-continuous mode and reaches a value of 5.5 mW at a current of 9 A in the pulsed mode.

  12. Synthesis, characterization and physical properties of the skutterudites Yb{sub x}Fe{sub 2}Ni{sub 2}Sb{sub 12} (0{<=}x{<=}0.4)

    SciTech Connect (OSTI)

    Kaltzoglou, Andreas; Vaqueiro, Paz; Knight, Kevin S.; Powell, Anthony V.

    2012-09-15

    The skutterudites Yb{sub x}Fe{sub 2}Ni{sub 2}Sb{sub 12} (0{<=}x{<=}0.4) have been prepared by solid-state reaction and characterised by powder X-ray diffraction. The compounds crystallise in the cubic space group Im3{sup Macron} (a Almost-Equal-To 9.1 A) with Yb atoms partially filling the voids in the skutterudite framework. A neutron time-of-flight diffraction experiment for Fe{sub 2}Ni{sub 2}Sb{sub 12} confirms the disorder of Fe and Ni atoms on the transition-metal site. Electrical resistivity, Seebeck coefficient and thermal conductivity measurements indicate that the thermoelectric performance of the skutterudites shows a marked dependence on the Yb content. Magnetic measurements over the temperature range 2{<=}T/K{<=}300 show paramagnetic behaviour for all compounds. Decomposition studies under an oxidising atmosphere at elevated temperatures have also been carried out by thermogravimetric analysis. - Graphical abstract: The filled skutterudites Yb{sub x}Fe{sub 2}Ni{sub 2}Sb{sub 12} have been prepared by solid-state reaction and characterised by powder X-ray diffraction. The thermoelectric performance depends strongly on the Yb content. The physical properties and thermal stability of the compounds are further discussed in comparison with the current state-of-the art thermoelectric skutterudites. Highlights: Black-Right-Pointing-Pointer A new series of skutterudites has been prepared and characterised. Black-Right-Pointing-Pointer Physical properties are affected by the degree of Yb filling. Black-Right-Pointing-Pointer The highest thermoelectric performance is found for Yb{sub 0.15}Fe{sub 2}Ni{sub 2}Sb{sub 12}. Black-Right-Pointing-Pointer The skutterudites decompose in air above 550 K.

  13. ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS

    E-Print Network [OSTI]

    ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS MOODY T. CHU Abstract. The wavefront aberrations induced by atmospheric turbulence can severely degrade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions

  14. ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS

    E-Print Network [OSTI]

    ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS MOODY T. CHU \\Lambda Abstract. The wavefront aberrations induced by atmospheric turbulence can severely degrade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions

  15. Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kong, P. P.; Sun, F.; Xing, L. Y.; Zhu, J.; Zhang, S. J.; Li, W. M.; Liu, Q. Q.; Wang, X. C.; Feng, S. M.; Yu, X. H.; et al

    2015-02-17

    Recently, A2B3 type strong spin orbital coupling compounds such as Bi2Te3, Bi2Se3 and Sb2Te3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb2Se3 on the other hand was found to be topological trivial, but theoretical studies indicated that the pressure might induce Sb2Se3 into a topological nontrivial state. We report on the discovery of superconductivity in Sb2Se3 single crystal induced via pressure. Our experiments indicated that Sb2Se3 became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related tomore »the topological quantum transition. The superconducting transition temperature (TC) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. High pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of TC slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.« less

  16. Performance Study of K2CsSb Photocathode Inside a DC High Voltage Gun

    SciTech Connect (OSTI)

    McCarter J. L.; Rao T.; Smedley, J.; Grames, J.; Mammei, R.; Poelker, M.; Suleiman, R.

    2011-09-01

    In the past decade, there has been considerable interest in the generation of tens of mA average current in a photoinjector. Until recently, GaAs:Cs cathodes and K{sub 2}CsSb cathodes have been tested successfully in DC and RF injectors respectively for this application. Our goal is to test the K{sub 2}CsSb photocathode inside a DC gun. Since the multialkali cathode is a compound with constant characteristics over its entire thickness, we anticipate that the lifetime issues seen in GaAs:Cs due to surface damage by ion bombardment would be minimized. Hence successful operation of the K{sub 2}CsSb cathode in a DC gun could lead to a relatively robust electron source capable of delivering ampere level currents. In order to test the performance of a K{sub 2}CsSb cathode in a DC gun, we have designed and built a load lock system that allows the fabrication of the cathode at Brookhaven National Lab (BNL) and its testing at Jefferson Lab (JLab). In this paper, we will present the performance of the K{sub 2}CsSb photocathode in the preparation chamber and in the DC gun.

  17. Lattice-registered growth of GaSb on Si (211) with molecular beam epitaxy

    SciTech Connect (OSTI)

    Hosseini Vajargah, S.; Botton, G. A.; Ghanad-Tavakoli, S.; Preston, J. S.; Kleiman, R. N.

    2012-11-01

    A GaSb film was grown on a Si(211) substrate using molecular beam epitaxy indicating full lattice relaxation as well as full lattice registration and dislocation-free growth in the plane perpendicular to the [01 - 1]-direction. Heteroepitaxy of GaSb on a Si(211) substrate is dominated by numerous first order and multiple higher order micro-twins. The atomic-resolved structural study of GaSb films by high-angle annular dark-field scanning transmission electron microscopy reveals that slight tilt, along with twinning, favors the lattice registry to Si(211) substrates. Preferential bonding of impinging Ga and Sb atoms at the interface due to two distinctive bonding sites on the Si(211) surface enables growth that is sublattice-ordered and free of anti-phase boundaries. The role of the substrate orientation on the strain distribution of GaSb epilayers is further elucidated by investigating the local change in the lattice parameter using the geometric phase analysis method and hence effectiveness of the lattice tilting in reducing the interfacial strain was confirmed further.

  18. Oceanography and Atmospheric Sciences

    E-Print Network [OSTI]

    Kurapov, Alexander

    Oceanography and Atmospheric Sciences 1959­2009 WayneBurt. #12;Oceanography and Atmospheric in Oceanography (TENOC). Wayne Burt immediately responds with proposal to President Strand of Oregon State College to start a graduate Department of Oceanography. 1959 Oregon State Board of Higher Education approves

  19. Structure of amorphous Ge8Sb2Te11: GeTe-Sb2Te3 alloys and optical storage J. Akola1,2,3

    E-Print Network [OSTI]

    of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland Received 28 January

  20. Electron Scattering in InSb Quantum Wells due to Micro-twin Defects

    SciTech Connect (OSTI)

    Mishima, T. D.; Santos, M. B. [Homer L. Dodge Department of Physics and Astronomy, and Center for Semiconductor Physics in Nanostructure University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States)

    2011-12-26

    The transport electron scattering due to micro-twin (MT) defects in InSb quantum wells (QWs) has been investigated at room temperature (RT). A linear-regression-based scattering analysis showed that Matthiessen's rule is applicable to the RT electron mobility in 20-nm-thick InSb QWs that contain MTs (whose density is 5.6x10{sup 2}-1.2x10{sup 4} /cm) and threading dislocations (8.7x10{sup 8}-3.2x10{sup 9} /cm{sup 2}) as dominant structural defects. For such an InSb QW whose local electron mobility in its non-MT regions is 2.8x10{sup 4}-4.5x10{sup 4} cm{sup 2}/(Vs), the MT-originated energy barrier against the electron transport is deduced to be 0.081-0.093 eV at RT.

  1. Natural nanostructure and superlattice nanodomains in AgSbTe{sub 2}

    SciTech Connect (OSTI)

    Carlton, Christopher E.; De Armas, Ricardo; Shao-Horn, Yang E-mail: shaohorn@mit.edu; Ma, Jie; May, Andrew F.; Delaire, Olivier E-mail: shaohorn@mit.edu

    2014-04-14

    AgSbTe{sub 2} has long been of interest for thermoelectric applications because of its favorable electronic properties and its low lattice thermal conductivity of ?0.7?W/mK. In this work, we report new findings from a high-resolution transmission electron microscopy study revealing two nanostructures in single crystal Ag{sub 1?x}Sb{sub 1+x}Sb{sub 2+x} (with x?=?0, 0.1, 0.2); (i) a rippled natural nanostructure with a period of ?2.5–5?nm and (ii) superlattice ordered nanodomains consistent with cation ordering predicted in previous density functional theory studies. These nanostructures, combined with point-defects, probably serve as sources of scattering for phonons, thereby yielding a low lattice thermal conductivity over a wide temperature range.

  2. INFERENCE OF INHOMOGENEOUS CLOUDS IN AN EXOPLANET ATMOSPHERE

    SciTech Connect (OSTI)

    Demory, Brice-Olivier; De Wit, Julien; Lewis, Nikole; Zsom, Andras; Seager, Sara; Fortney, Jonathan; Knutson, Heather; Desert, Jean-Michel; Heng, Kevin; Madhusudhan, Nikku; Gillon, Michael; Barclay, Thomas; Cowan, Nicolas B.

    2013-10-20

    We present new visible and infrared observations of the hot Jupiter Kepler-7b to determine its atmospheric properties. Our analysis allows us to (1) refine Kepler-7b's relatively large geometric albedo of Ag = 0.35 ± 0.02, (2) place upper limits on Kepler-7b thermal emission that remains undetected in both Spitzer bandpasses and (3) report a westward shift in the Kepler optical phase curve. We argue that Kepler-7b's visible flux cannot be due to thermal emission or Rayleigh scattering from H{sub 2} molecules. We therefore conclude that high altitude, optically reflective clouds located west from the substellar point are present in its atmosphere. We find that a silicate-based cloud composition is a possible candidate. Kepler-7b exhibits several properties that may make it particularly amenable to cloud formation in its upper atmosphere. These include a hot deep atmosphere that avoids a cloud cold trap, very low surface gravity to suppress cloud sedimentation, and a planetary equilibrium temperature in a range that allows for silicate clouds to potentially form in the visible atmosphere probed by Kepler. Our analysis does not only present evidence of optically thick clouds on Kepler-7b but also yields the first map of clouds in an exoplanet atmosphere.

  3. Behavior Observation Lab Equipment Manual Room SB208 04/16/14 Behavior Science Core, CHDD, University of Washington 1

    E-Print Network [OSTI]

    Behavior Observation Lab Equipment Manual Room SB208 04/16/14 Behavior Science Core, CHDD visit or out of town researcher is scheduled to be in the lab. #12;Behavior Observation Lab Equipment the breeze from moving the shade out of it's track. #12;Behavior Observation Lab Equipment Manual Room SB208

  4. Stress relief from reconstructions on SbSi,,001... Yao He, X. H. Zhang, and J. G. Che*

    E-Print Network [OSTI]

    Che, Jingguang

    Stress relief from reconstructions on SbÕSi,,001... Yao He, X. H. Zhang, and J. G. Che* Surface; revised manuscript recieved 15 April 2002; published 11 November 2002 The structures and stress of the Sb)2 1 surface is found to be under a tensile stress of 1.0 eV/(1 1 cell along the dimer bond

  5. Evaluation Of Glass Density To Support The Estimation Of Fissile Mass Loadings From Iron Concentrations In SB8 Glasses

    SciTech Connect (OSTI)

    Edwards, T. B.; Peeler, D. K.; Kot, W. K.; Gan, H.; Pegg, I. L.

    2013-04-30

    The Department of Energy – Savannah River (DOE-SR) has provided direction to Savannah River Remediation (SRR) to maintain fissile concentration in glass below 897 g/m{sup 3}. In support of that guidance, the Savannah River National Laboratory (SRNL) provided a technical basis and a supporting Microsoft® Excel® spreadsheet for the evaluation of fissile loading in Sludge Batch 5 (SB5), Sludge Batch 6 (SB6), Sludge Batch 7a (SB7a), and Sludge Batch 7b (SB7b) glass based on the iron (Fe) concentration in glass as determined by the measurements from the Slurry Mix Evaporator (SME) acceptability analysis. SRR has since requested that the necessary density information be provided to allow SRR to update the Excel® spreadsheet so that it may be used to maintain fissile concentration in glass below 897 g/m{sup 3} during the processing of Sludge Batch 8 (SB8). One of the primary inputs into the fissile loading spreadsheet includes an upper bound for the density of SB8-based glasses. Thus, these bounding density values are to be used to assess the fissile concentration in this glass system. It should be noted that no changes are needed to the underlying structure of the Excel-based spreadsheet to support fissile assessments for SB8. However, SRR should update the other key inputs to the spreadsheet that are based on fissile and Fe concentrations reported from the SB8 Waste Acceptance Product Specification (WAPS) sample.

  6. Ensemble Atmospheric Dispersion Modeling

    SciTech Connect (OSTI)

    Addis, R.P.

    2002-06-24

    Prognostic atmospheric dispersion models are used to generate consequence assessments, which assist decision-makers in the event of a release from a nuclear facility. Differences in the forecast wind fields generated by various meteorological agencies, differences in the transport and diffusion models, as well as differences in the way these models treat the release source term, result in differences in the resulting plumes. Even dispersion models using the same wind fields may produce substantially different plumes. This talk will address how ensemble techniques may be used to enable atmospheric modelers to provide decision-makers with a more realistic understanding of how both the atmosphere and the models behave.

  7. Nanoscale structure in AgSbTe2 determined by diffuse elastic neutron scattering

    SciTech Connect (OSTI)

    Specht, Eliot D [ORNL; Ma, Jie [ORNL; Delaire, Olivier A [ORNL; Budai, John D [ORNL; May, Andrew F [ORNL; Karapetrova, Evguenia A. [Argonne National Laboratory (ANL)

    2015-01-01

    Diffuse elastic neutron scattering measurements confirm that AgSbTe2 has a hierarchical structure, with defects on length scales from nanometers to microns. While scattering from mesoscale structure is consistent with previously-proposed structures in which Ag and Sb order on a NaCl lattice, more diffuse scattering from nanoscale structure suggests a structural rearrangement in which hexagonal layers form a combination of (ABC), (ABA), and (AAB) stacking sequences. The AgCrSe2 structure is the best-fitting model for the local atomic arrangements.

  8. A new method based on Markov chains for deriving SB2 orbits directly from their spectra

    E-Print Network [OSTI]

    Salomon, J -B; Guillout, P; Halbwachs, J -L; Arenou, F; Famaey, B; Lebreton, Y; Mazeh, T; Pourbaix, D; Tal-Or, L

    2012-01-01

    We present a new method to derive orbital elements of double-lined spectroscopic binaries (SB2). The aim is to have accurate orbital parameters of a selection of SB2 in order to prepare the exploitation of astrometric Gaia observations. Combined with our results, they should allow one to measure the mass of each star with a precision of better than 1%. The new method presented here consists of using the spectra at all epochs simultaneously to derive the orbital elements without templates. It is based on a Markov chain including a new method for disentangling the spectra.

  9. Flat Plate PV Module Eligibility Listing Procedure Updated 6/2/14 Senate Bill 1 (SB1) defines the solar incentive programs for California, and flat plate PV

    E-Print Network [OSTI]

    Flat Plate PV Module Eligibility Listing Procedure Updated 6/2/14 Senate Bill 1 (SB1) defines the solar incentive programs for California, and flat plate PV modules 1 must be listed on the SB1 for adding PV modules to the SB1 list is as follows: 1 . Data submitted to the Energy Commission

  10. Optical humidity sensor

    DOE Patents [OSTI]

    Tarvin, Jeffrey A. (Ann Arbor, MI)

    1987-01-01

    An optical dielectric humidity sensor which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors.

  11. Optical humidity sensor

    DOE Patents [OSTI]

    Tarvin, J.A.

    1987-02-10

    An optical dielectric humidity sensor is disclosed which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors. 2 figs.

  12. Toxicity of atmospheric aerosols on marine phytoplankton

    E-Print Network [OSTI]

    2009-01-01

    address: Center for Atmospheric Chemistry Study, Departmenttween phytoplankton, atmospheric chemistry, and climate areno. 12 ? 4601– 4605 CHEMISTRY Atmospheric aerosol deposition

  13. Optical Turbulence Characterization at LAMOST Site: Observations and Models

    E-Print Network [OSTI]

    Liu, L -Y; Yao, Y -Q; Vernin, J; Chadid, M; Wang, H -S; Yin, J; Wang, Y -P

    2015-01-01

    Atmospheric optical turbulence seriously limits the performance of high angular resolution instruments. An 8-night campaign of measurements was carried out at the LAMOST site in 2011, to characterize the optical turbulence. Two instruments were set up during the campaign: a Differential Image Motion Monitor (DIMM) used to measure the total atmospheric seeing, and a Single Star Scidar (SSS) to measure the vertical profiles of the turbulence C_n^2(h) and the horizontal wind velocity V(h). The optical turbulence parameters are also calculated with the Weather Research and Forecasting (WRF) model coupled with the Trinquet-Vernin model, which describes optical effects of atmospheric turbulence by using the local meteorological parameters. This paper presents assessment of the optical parameters involved in high angular resolution astronomy. Its includes seeing, isoplanatic angle, coherence time, coherence etendue, vertical profiles of optical turbulence intensity _n^2(h)$ and horizontal wind speed V(h). The median...

  14. Autumn 2014 Atmospheric Circulation

    E-Print Network [OSTI]

    Doty, Sharon Lafferty

    to perform atmospheric chemistry measurements in this remote region of ubiquitous oil and gas drilling 30 days they raised $12,000, enough to support Maria's travel to Utah and to cover the costs

  15. 2254 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 42, NO. 10, OCTOBER 2004 Retrieval of Semitransparent Ice Cloud Optical

    E-Print Network [OSTI]

    Li, Jun

    of Semitransparent Ice Cloud Optical Thickness From Atmospheric Infrared Sounder (AIRS) Measurements Heli Wei, Ping Abstract--An approach is developed to infer the optical thick- ness of semitransparent ice clouds (when optical thickness is less than 5) from Atmospheric Infrared Sounder (AIRS) high spectral resolution

  16. Masses of the components of SB2 binaries observed with Gaia. I. Selection of the sample and mass ratios of 20 new SB2s discovered with Sophie

    E-Print Network [OSTI]

    Halbwachs, Jean-Louis; Pourbaix, Dimitri; Famaey, Benoît; Guillout, Patrick; Lebreton, Yveline; Salomon, Jean-Baptiste; Tal-Or, Lev; Ibata, Rodrigo; Mazeh, Tsevi

    2014-01-01

    In anticipation of the Gaia astrometric mission, a large sample of spectroscopic binaries is being observed since 2010 with the Sophie spectrograph at the Haute--Provence Observatory. Our aim is to derive the orbital elements of double-lined spectroscopic binaries (SB2s) with an accuracy sufficient to finally obtain the masses of the components with relative errors as small as 1% when the astrometric measurements of Gaia are taken into account. Simultaneously, the luminosities of the components in the Gaia photometric band G will also be obtained. Our observation program started with 200 SBs, including 152 systems that were only known as single-lined. Thanks to the high efficiency of the Sophie spectrograph, an additional component was found for 25 SBs. After rejection of 5 multiple systems, 20 new SB2s were retained, including 8 binaries with evolved primary, and their mass ratios were derived. Our final sample contains 68 SB2s, including 2 late-type giants and 10 other evolved stars.

  17. Adaptive Optics for Large Telescopes

    SciTech Connect (OSTI)

    Olivier, S

    2008-06-27

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments.

  18. Journal of Crystal Growth 304 (2007) 399401 Growth of high quality, epitaxial InSb nanowires

    E-Print Network [OSTI]

    Wang, Zhong L.

    2007-01-01

    Journal of Crystal Growth 304 (2007) 399­401 Growth of high quality, epitaxial InSb nanowires Hyun, Washington, DC. 20375, USA b School of Materials Science and Engineering, Georgia Institute of Technology March 2007 Communicated by R.M. Biefeld Available online 1 April 2007 Abstract The growth of In

  19. High resolution InSb quantum well ballistic nanosensors for room temperature applications

    SciTech Connect (OSTI)

    Gilbertson, Adam; Cohen, L. F.; Lambert, C. J.; Solin, S. A.

    2013-12-04

    We report the room temperature operation of a quasi-ballistic InSb quantum well Hall sensor that exhibits a high frequency sensitivity of 560nT/?Hz at 20uA bias current. The device utilizes a partitioned buffer layer design that suppresses leakage currents through the mesa floor and can sustain large current densities.

  20. John von Neumann Institute for Computing Structural Patterns in Ge/Sb/Te Phase-Change

    E-Print Network [OSTI]

    of the phases involved and the nature of the phase transition in the nanoscale bits pose continuing challenges square'. The rapid amorphous- to-crystalline phase change can be viewed as a re-orientation of disorderedJohn von Neumann Institute for Computing Structural Patterns in Ge/Sb/Te Phase-Change Materials J

  1. Performance Study of K2CsSb Photocathode inside a DC High Voltage Gun

    SciTech Connect (OSTI)

    T. Rao, J. Smedley, J.M. Grames, R. Mammei, J.L. McCarter, M. Poelker, R. Suleiman

    2011-03-01

    In the past decade, there has been considerable interest in the generation of tens of mA average current in a photoinjector. Until recently, GaAs:Cs cathodes and K2CsSb cathodes have been tested successfully in DC and RF injectors respectively for this application. Our goal is to test the GaAs:Cs in RF injector and the K2CsSb cathode in the DC gun in order to widen our choices. Since the multialkali cathode is a compound with uniform stochiometry over its entire thickness, we anticipate that the life time issues seen in GaAs:Cs due surface damage by ion bombardment would be minimized with this material. Hence successful operation of the K2CsSb cathode in DC gun could lead to a relatively robust electron source capable of delivering ampere level currents. In order to test the performance of K2CsSb cathode in a DC gun, we have designed and built a load lock system that would allow the fabrication of the cathode at BNL and its testing at JLab. In this paper, we will present the design of the load-lock system, cathode fabrication, and the cathode performance in the preparation chamber and in the DC gun.

  2. Artificial Markets and Intelligent Agents S.B. Massachusetts Institute of Technology (1995)

    E-Print Network [OSTI]

    Poggio, Tomaso

    1995-01-01

    Artificial Markets and Intelligent Agents by Tung Chan S.B. Massachusetts Institute of Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Arthur C. Smith Chairman, Departmental Committee on Graduate Students #12;#12;Artificial Markets and Intelligent Agents by Tung Chan Submitted to the Department of Electrical Engineering and Computer Science

  3. Colorado State Forest Service SB09-020 --Responsibility for Responding to Wildland Fires

    E-Print Network [OSTI]

    Colorado State Forest Service SB09-020 -- Responsibility for Responding to Wildland Fires Summary, and the Colorado State Forest Service in responding to wildland fires. This legislation organizes the roles Forest Service may assist the sheriff in controlling or extinguishing such fires, and may assume command

  4. The radiation chemistry of Cs-7SB, a solvent modifier used in Cs and Sr extraction

    SciTech Connect (OSTI)

    Mincher, B.J.; Martin, L.R.; Elias, G.; Mezyk, S.P.

    2008-07-01

    The solvent modifier 1-(2,2,3,3-tetrafluoro-propoxy)-3-(4-sec-butylphenoxy)-2-propanol, (Cs- 7SB) is used in conjunction with calixarenes and crown ethers dissolved in alkane diluents for the extraction of Cs and Sr from highly radioactive solutions. Its purpose is to solvate the ligands and the resulting ligand-metal complexes in the organic phase. Given this role, and its relatively high concentration in the formulations used for solvent extraction, radiolytic degradation of Cs-7SB might decrease the extraction efficiency of these elements as the solvent accumulates absorbed radiation dose. This work presents the results of studies of Cs-7SB using post-radiolysis gas chromatography with electron-capture detection and solvent-extraction distribution-ratio measurements. Also presented is the kinetic analysis of the bimolecular rate constant for the modifier's reaction with nitrogen trioxide and nitrogen dioxide radicals, major radiolytically-produced radical species in irradiated aqueous nitric acid. Although Cs-7SB was found to undergo reactions with nitrogen-centered radicals, little decrease in extraction efficiency was found. It is concluded the modifier, always present at concentrations much higher than the ligands, acts as a radical scavenger, protecting ligands from radiolytic attack. (authors)

  5. Structural evolution and characterization of heteroepitaxial GaSb thin films on Si(111) substrates

    SciTech Connect (OSTI)

    Nguyen, Thang; Varhue, Walter; Cross, Michael; Pino, Robinson; Adams, Edward; Lavoie, Mark; Lee, Jaichan [School of Engineering, University of Vermont, Burlington, Vermont 05405 (United States); IBM Corporation, Essex Junction, Vermont 05452 (United States); Department of Materials Science and Engineering, Sung Kyun Kwan University, Suwon 440-746 (Korea, Republic of)

    2007-04-01

    This paper describes the structural evolution and characterization of heteroepitaxial GaSb thin films on Si(111) substrates. The growth process used a combination of atomic sources which included the rf sputtering of Sb and the thermal effusion of Ga. The formation of crystalline GaSb thin films required that initially a monolayer thick Sb buffer layer be applied directly to a clean H-passivated Si(111) substrate surface. The resulting film was characterized by high resolution x-ray diffraction, Rutherford backscattering spectrometry, transmission electron microscopy, secondary ion mass spectroscopy, and atomic force microscopy (AFM). The AFM images were taken from the material after several periods of growth to determine the evolution of crystal structure with thickness. Atomic force microscopy images of the film surface showed that the heteroepitaxial layers were formed via the Stranski-Krastanov growth mechanism. This result is consistent with the heteroepitaxial growth of systems representing large differences in lattice constant. The hole mobility and carrier concentration in the deposited material were determined by the Hall measurement, performed at room temperature and on a 140 nm thick sample, to be 66 cm{sup 2}/V sec and 3x10{sup 19} cm{sup -3}, respectively. The carrier mobility was relatively low as expected for measurements taken at room temperature.

  6. Planning for sustainable communities: Regional incentives and local policy under SB375

    E-Print Network [OSTI]

    California at Davis, University of

    -Claudia Sciara, Ph.D., AICP Urban Land Use and Transportation Center University of California, Davis Policy Institute Policy for Energy, Environment and the Economy University of California, Davis March 19, 2014Sacramento Los Angeles S.F. Bay Area Land use component of regional transportation plans #12;2013 SB375

  7. TANK 40 FINAL SB5 CHEMICAL CHARACTERIZATION RESULTS PRIOR TO NP ADDITION

    SciTech Connect (OSTI)

    Bannochie, C.; Click, D.

    2010-01-06

    A sample of Sludge Batch 5 (SB5) was pulled from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). This sample was also analyzed for chemical composition including noble metals. Prior to radionuclide inventory analyses, a final sample of the H-canyon Np stream will be added to bound the Np addition anticipated for Tank 40. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to DWPF as SB5. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB5 sample was transferred from the shipping container into a 4-L high density polyethylene vessel and solids allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 239 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon{reg_sign} vessels and four in Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Due to the use of Zr crucibles and Na in the peroxide fusions, Na and Zr cannot be determined from this preparation. Additionally, other alkali metals, such as Li and K that may be contaminants in the Na{sub 2}O{sub 2} are not determined from this preparation. Three Analytical Reference Glass - 14 (ARG-1) standards were digested along with a blank for each preparation. The ARG-1 glass allows for an assessment of the completeness of each digestion. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma - atomic emission spectroscopy (ICPAES) analysis, inductively coupled plasma - mass spectrometry (ICP-MS) analysis of masses 81-209 and 230-252, and cold vapor atomic absorption (CV-AA) analysis for Hg. Equivalent dilutions of the peroxide fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB5 supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES. Weighted dilutions of slurry were submitted for ion chromatography (IC), total inorganic carbon/total organic carbon (TIC/TOC), and total base analyses. The following conclusions were drawn from the analytical results reported here: (1) The elemental ratios of the major elements for the SB5 WAPS sample, whose major Tank 51 Qualification sample component underwent Al dissolution, are similar to those measured for the SB4 WAPS sample. (2) The elemental composition of this sample and the analyses conducted here are reasonable and consistent with DWPF batch data measurements in light of DWPF pre-sample concentration and SRAT product heel contributions to the DWPF SRAT receipt analyses. (3) Fifty percent of the sulfur in the SB5 WAPS sample is insoluble, and this represents a significantly larger fraction than that observed in previous sludge batches. (4) The noble metal and Ag concentrations predicted from the measured values for the Tank 51 Confirmation sample and Tank 40 SB4 WAPS sample using a two-thirds Tank 51, one-third Tank 40 heel blend ratio used to arrive at the final SB5 composition, agree with the values for the Tank 40 SB5 WAPS sample measured for this report.

  8. 13, 1479714822, 2013 Atmospheric waves

    E-Print Network [OSTI]

    Lovejoy, Shaun

    .5194/acpd-13-14797-2013 © Author(s) 2013. CC Attribution 3.0 License. Sciences ss Atmospheric Chemistry and Physics OpenAccess Atmospheric Chemistry and Physics OpenAccess Discussions Atmospheric Measurement s Discussions This discussion paper is/has been under review for the journal Atmospheric Chemistry and Physics

  9. Improved detection of atmospheric turbulence with SLODAR

    E-Print Network [OSTI]

    Michael Goodwin; Charles Jenkins; Andrew Lambert

    2007-06-19

    We discuss several improvements in the detection of atmospheric turbulence using SLOpe Detection And Ranging (SLODAR). Frequently, SLODAR observations have shown strong ground-layer turbulence, which is beneficial to adaptive optics. We show that current methods which neglect atmospheric propagation effects can underestimate the strength of high altitude turbulence by up to ~ 30%. We show that mirror and dome seeing turbulence can be a significant fraction of measured ground-layer turbulence, some cases up to ~ 50%. We also demonstrate a novel technique to improve the nominal height resolution, by a factor of 3, called Generalized SLODAR. This can be applied when sampling high-altitude turbulence, where the nominal height resolution is the poorest, or for resolving details in the important ground-layer.

  10. Observations of Exoplanet Atmospheres

    E-Print Network [OSTI]

    Crossfield, Ian J M

    2015-01-01

    Detailed characterization of an extrasolar planet's atmosphere provides the best hope for distinguishing the makeup of its outer layers, and the only hope for understanding the interplay between initial composition, chemistry, dynamics & circulation, and disequilibrium processes. In recent years, some areas have seen rapid progress while developments in others have come more slowly and/or have been hotly contested. This article gives an observer's perspective on the current understanding of extrasolar planet atmospheres prior to the considerable advances expected from the next generation of observing facilities. Atmospheric processes of both transiting and directly-imaged planets are discussed, including molecular and atomic abundances, cloud properties, thermal structure, and planetary energy budgets. In the future we can expect a continuing and accelerating stream of new discoveries, which will fuel the ongoing exoplanet revolution for many years to come.

  11. Clear sky atmosphere at cm-wavelengths from climatology data

    E-Print Network [OSTI]

    Lew, Bartosz

    2015-01-01

    We utilise ground-based, balloon-born and satellite climatology data to reconstruct site and season-dependent vertical profiles of precipitable water vapour (PWV). We use these profiles to numerically solve radiative transfer through the atmosphere, and derive atmospheric brightness temperature ($T_{\\rm atm}$) and optical depth ($\\tau$) at the centimetre wavelengths. We validate the reconstruction by comparing the model column PWV, with photometric measurements of PWV, performed in the clear sky conditions towards the Sun. Based on the measurements, we devise a selection criteria to filter the climatology data to match the PWV levels to the expectations of the clear sky conditions. We apply the reconstruction to the location of the Polish 32-metre radio telescope, and characterise $T_{\\rm atm}$ and $\\tau$ year-round, at selected frequencies. We also derive the zenith distance dependence for these parameters, and discuss shortcomings of using planar, single-layer, and optically thin atmospheric model approxima...

  12. Direct Evidence for Abrupt Postcrystallization Germanium Precipitation in Thin Phase-Change Films of Sb-15 at. % Ge

    SciTech Connect (OSTI)

    Cabral,C.; Krusin-Elbaum, L.; Bruley, J.; Raoux, S.; Deline, V.; Madan, A.; Pinto, T.

    2008-01-01

    We present evidence for the instability in the crystalline (metallic) state of binary Te-free phase-change Ge-Sb thin films considered for integration into nonvolatile nanosized memory cells. We find that while the amorphous (semiconducting) phase of eutectic Sb-15 at. % Ge is very robust until Sb crystallization at 240 C, at about 350 C, germanium rapidly precipitates out. Ge precipitation, visualized directly with transmission electron microscopy, is exothermic and is found to affect the films' reflectivity, resistance, and stress. It converts melting into a two-step process, which may seriously impact the switching reliability of a device.

  13. Temperature-dependent structural property and power factor of n type thermoelectric Bi{sub 0.90}Sb{sub 0.10} and Bi{sub 0.86}Sb{sub 0.14} alloys

    SciTech Connect (OSTI)

    Malik, K.; Das, Diptasikha; Bandyopadhyay, S.; Banerjee, Aritra; Center for Research in Nanoscience and Nanotechnology, University of Calcutta, JD-2, Sector-III, Saltlake City, Kolkata 700 098 ; Mandal, P.; Srihari, Velaga

    2013-12-09

    Thermal variation of structural property, linear thermal expansion coefficient (?), resistivity (?), thermopower (S), and power factor (PF) of polycrystalline Bi{sub 1-x}Sb{sub x} (x?=?0.10 and 0.14) samples are reported. Temperature-dependent powder diffraction experiments indicate that samples do not undergo any structural phase transition. Rietveld refinement technique has been used to perform detailed structural analysis. Temperature dependence of ? is found to be stronger for Bi{sub 0.90}Sb{sub 0.10}. Also, PF for direct band gap Bi{sub 0.90}Sb{sub 0.10} is higher as compared to that for indirect band gap Bi{sub 0.86}Sb{sub 0.14}. Role of electron-electron and electron-phonon scattering on ?, S, and PF has been discussed.

  14. Autumn 2012 Atmospheric Circulation

    E-Print Network [OSTI]

    Doty, Sharon Lafferty

    wind, and accumulated precipitation at a designated city. Forecasts are made over a two-week period Department 1 The UW Atmospheric Sciences spring forecast contest has been an annual tradition there will be a marine push or a convergence zone wrecking their forecast for maximum temperature and precipitation

  15. Laboratory for Atmospheric and

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Laboratory for Atmospheric and Space Physics Activity Report 2013 University of Colorado at Boulder from the Naval Research Center and the Air Force Cambridge Research Laboratory (now the Phillips Laboratory), the University of Colorado formed a research group called the Upper Air Laboratory (UAL

  16. Laboratory for Atmospheric and

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Laboratory for Atmospheric and Space Physics Activity Report 2012 University of Colorado at Boulder from the Naval Research Center and the Air Force Cambridge Research Laboratory (now the Phillips Laboratory), the University of Colorado formed a research group called the Upper Air Laboratory (UAL

  17. Laboratory for Atmospheric and

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Laboratory for Atmospheric and Space Physics Activity Report 2008 University of Colorado at Boulder, Jet Propulsion Laboratory) LASP: A Brief History In 1946-47, a handful of American universities joined Laboratory (now the Phillips Laboratory), the University of Colorado formed a research group called the Upper

  18. Laboratory for Atmospheric and

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    1 Laboratory for Atmospheric and Space Physics Activity Report 2010 University of Colorado from the Na- val Research Center and the Air Force Cambridge Research Laboratory (now the Phillips Laboratory), the University of Colorado formed a research group called the Upper Air Laboratory (UAL

  19. ATMOSPHERIC CHEMISTRY AND PHYSICS

    E-Print Network [OSTI]

    Brandenburg, Axel

    of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com. Library of Congress Cataloging components of the atmosphere, nitrogen, oxygen, water, carbon dioxide, and the noble gases. In the late

  20. Growth, strain relaxation properties and high-? dielectric integration of mixed-anion GaAs{sub 1-y}Sb{sub y} metamorphic materials

    SciTech Connect (OSTI)

    Zhu, Y.; Clavel, M.; Goley, P.; Hudait, M. K., E-mail: mantu.hudait@vt.edu [Advanced Devices and Sustainable Energy Laboratory (ADSEL), Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2014-10-07

    Mixed-anion, GaAs{sub 1-y}Sb{sub y} metamorphic materials with a wide range of antimony (Sb) compositions extending from 15% to 62%, were grown by solid source molecular beam epitaxy (MBE) on GaAs substrates. The impact of different growth parameters on the Sb composition in GaAs{sub 1-y}Sb{sub y} materials was systemically investigated. The Sb composition was well-controlled by carefully optimizing the As/Ga ratio, the Sb/Ga ratio, and the substrate temperature during the MBE growth process. High-resolution x-ray diffraction demonstrated a quasi-complete strain relaxation within each composition of GaAs{sub 1-y}Sb{sub y}. Atomic force microscopy exhibited smooth surface morphologies across the wide range of Sb compositions in the GaAs{sub 1-y}Sb{sub y} structures. Selected high-? dielectric materials, Al{sub 2}O{sub 3}, HfO{sub 2}, and Ta{sub 2}O{sub 5} were deposited using atomic layer deposition on the GaAs{sub 0.38}Sb{sub 0.62} material, and their respective band alignment properties were investigated by x-ray photoelectron spectroscopy (XPS). Detailed XPS analysis revealed a valence band offset of >2 eV for all three dielectric materials on GaAs{sub 0.38}Sb{sub 0.62}, indicating the potential of utilizing these dielectrics on GaAs{sub 0.38}Sb{sub 0.62} for p-type metal-oxide-semiconductor (MOS) applications. Moreover, both Al{sub 2}O{sub 3} and HfO{sub 2} showed a conduction band offset of >2 eV on GaAs{sub 0.38}Sb{sub 0.62}, suggesting these two dielectrics can also be used for n-type MOS applications. The well-controlled Sb composition in several GaAs{sub 1-y}Sb{sub y} material systems and the detailed band alignment analysis of multiple high-? dielectric materials on a fixed Sb composition, GaAs{sub 0.38}Sb{sub 0.62}, provides a pathway to utilize GaAs{sub 1-y}Sb{sub y} materials in future microelectronic and optoelectronic applications.

  1. Use of a Seeing Monitor to Determine the Velocities of Turbulent Atmospheric Layers

    E-Print Network [OSTI]

    Meisner, Jeff

    with ground based interferometers and adaptive optics systems, as well as in statistical studies of seeing- tical astronomical images well beyond the di#11;raction limit of the telescopes. An adaptive optics;erential atmospheric delay a#11;ecting the light received at separated points. In all such ground

  2. Atmospheric contamination for CMB ground-based observations

    E-Print Network [OSTI]

    Errard, J; Akiba, Y; Arnold, K; Atlas, M; Baccigalupi, C; Barron, D; Boettger, D; Borrill, J; Chapman, S; Chinone, Y; Cukierman, A; Delabrouille, J; Dobbs, M; Ducout, A; Elleflot, T; Fabbian, G; Feng, C; Feeney, S; Gilbert, A; Goeckner-Wald, N; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Hill, C; Holzapfel, W L; Hori, Y; Inoue, Y; Jaehnig, G C; Jaffe, A H; Jeong, O; Katayama, N; Kaufman, J; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Jeune, M Le; Lee, A T; Leitch, E M; Leon, D; Linder, E; Matsuda, F; Matsumura, T; Miller, N J; Myers, M J; Navaroli, M; Nishino, H; Okamura, T; Paar, H; Peloton, J; Poletti, D; Puglisi, G; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Rotermund, K M; Schenck, D E; Sherwin, B D; Siritanasak, P; Smecher, G; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Tajima, O; Takakura, S; Tikhomirov, A; Tomaru, T; Whitehorn, N; Wilson, B; Yadav, A; Zahn, O

    2015-01-01

    Atmosphere is one of the most important noise sources for ground-based Cosmic Microwave Background (CMB) experiments. By increasing optical loading on the detectors, it amplifies their effective noise, while its fluctuations introduce spatial and temporal correlations between detected signals. We present a physically motivated 3d-model of the atmosphere total intensity emission in the millimeter and sub-millimeter wavelengths. We derive an analytical estimate for the correlation between detectors time-ordered data as a function of the instrument and survey design, as well as several atmospheric parameters such as wind, relative humidity, temperature and turbulence characteristics. Using numerical computation, we examine the effect of each physical parameter on the correlations in the time series of a given experiment. We then use a parametric-likelihood approach to validate the modeling and estimate atmosphere parameters from the POLARBEAR-I project first season data set. We compare our results to previous st...

  3. Nanostructured Ge{sub 2}Sb{sub 2}Te{sub 5} chalcogenide films produced by laser electrodispersion

    SciTech Connect (OSTI)

    Yavsin, D. A., E-mail: yavsin@mail.ioffe.ru; Kozhevin, V. M.; Gurevich, S. A.; Yakovlev, S. A.; Melekh, B. T.; Yagovkina, M. A.; Pevtsov, A. B. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2014-12-15

    Amorphous nanostructured films of a complex chalcogenide (Ge{sub 2}Sb{sub 2}Te{sub 5}) are produced by laser electrodispersion and their structural and electrical properties are studied. It is found that the characteristic size of Ge{sub 2}Sb{sub 2}Te{sub 5} nanoparticles in the structure of the films is 1.5–5 nm.

  4. Surface alloy model of p(2 2)Sb/Cu(001) from LEED I/V data Shougo Higashi a

    E-Print Network [OSTI]

    Saldin, Dilano

    Surface alloy model of p(2 Â 2)Sb/Cu(001) from LEED I/V data Shougo Higashi a , Hiroshi Tochihara 2008 Keywords: Surface structure Metallic surfaces LEED Chemisorption a b s t r a c t We report on the re-determination of the structure of p(2 Â 2)Sb/Cu(001) from measured LEED I/V data. The structure

  5. Fiber Optics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    said Todd Eckman, vice president of Information Management for MSA. "This new fiber optics will benefit DOE, Benton PUD and NoaNet (Northwest Open Access Network) users. This,...

  6. Irreversible altering of crystalline phase of phase-change Ge-Sb thin films

    SciTech Connect (OSTI)

    Krusin-Elbaum, L.; Shakhvorostov, D.; Cabral, C. Jr.; Raoux, S.; Jordan-Sweet, J. L.

    2010-03-22

    The stability of the crystalline phase of binary phase-change Ge{sub x}Sb{sub 1-x} films is investigated over a wide range of Ge content. From Raman spectroscopy we find the Ge-Sb crystalline structure irreversibly altered after exposure to a laser beam. We show that with increasing beam intensity/temperature Ge agglomerates and precipitates out in the amount growing with x. A simple empirical relation links Ge precipitation temperature T{sub Ge}{sup p} to the rate of change dT{sub cryst}/dx of crystallization, with the precipitation easiest on the mid-range x plateau, where T{sub cryst} is nearly constant. Our findings point to a preferable 15% < or approx. x < 50% window, that may achieve the desired cycling/archival properties of a phase-change cell.

  7. Differential atmospheric tritium sampler

    DOE Patents [OSTI]

    Griesbach, O.A.; Stencel, J.R.

    1987-10-02

    An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The moisture then passes through a combustion chamber where hydrogen gas in the form of H/sub 2/ or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

  8. Thin-film Sb2Se3 photovoltaics with oriented one-dimensional ribbons and benign

    E-Print Network [OSTI]

    Sargent, Edward H. "Ted"

    to the substrate, and produced Sb2Se3 thin-film solar cells with a certified device efficiency of 5.6%. Our results are one of the major limiting factors for high-efficiency thin-film solar cells. We began with first cells based on inorganic absorbers, such as Si, GaAs, CdTe and Cu(In,Ga)Se2, permit a high device

  9. Terahertz emission from Ga1-xInxSb Ricardo Ascazubi and Ingrid Wilke

    E-Print Network [OSTI]

    Wilke, Ingrid

    by semiconductor properties. Narrow direct band gap semiconductors such as InAs Eg=0.35 eV ,8­16 and InN Eg=0.68 eInxSb with 0 x 1. THz emission is excited by femtosecond near-infrared laser pulses. For this material system as a result of carrier compensation NA NB for this specific material composition. The THz emission from n

  10. Bi flux-dependent MBE growth of GaSbBi alloys

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rajpalke, M. K.; Linhart, W. M.; Yu, K. M.; Jones, T. S.; Ashwin, M. J.; Veal, T. D.

    2015-09-01

    The incorporation of Bi in GaSb1-xBix alloys grown by molecular beam epitaxy is investigated as a function of Bi flux at fixed growth temperature (275 °C) and growth rate (1 ?m h?¹). The Bi content is found to vary proportionally with Bi flux with Bi contents, as measured by Rutherford backscattering, in the range 0more »with a reduction of ~32 meV/%Bi.« less

  11. Electronic structure of rare-earth chromium antimonides RECrSb{sub 3} (RE=La-Nd, Sm, Gd-Dy, Yb) by X-ray photoelectron spectroscopy

    SciTech Connect (OSTI)

    Crerar, Shane J. [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada)] [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada); Mar, Arthur, E-mail: arthur.mar@ualberta.ca [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada)] [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada); Grosvenor, Andrew P. [Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5C9 (Canada)] [Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5C9 (Canada)

    2012-12-15

    The electronic structure of the ternary rare-earth chromium antimonides RECrSb{sub 3} (RE=La-Nd, Sm, Gd-Dy, Yb) has been examined by high-resolution X-ray photoelectron spectroscopy (XPS) for the first time. The RE 3d or 4d core-line spectra are substantially complicated by the presence of satellite peaks but their general resemblance to those of RE{sub 2}O{sub 3} tends to support the presence of trivalent RE atoms in RECrSb{sub 3}. However, the Yb 4d spectrum of YbCrSb{sub 3} also shows peaks that are characteristic of divalent ytterbium. The Cr 2p core-line spectra exhibit asymmetric lineshapes and little change in binding energy (BE) relative to Cr metal, providing strong evidence for electronic delocalization. The Sb 3d core-line spectra reveal slightly negative BE shifts relative to elemental antimony, supporting the presence of anionic Sb species in RECrSb{sub 3}. The experimental valence band spectrum of LaCrSb{sub 3} matches well with the calculated density of states, and it can be fitted to component peaks belonging to individual atoms to yield an average formulation that agrees well with expectations ('La{sup 3+}Cr{sup 3+}(Sb{sup 2-}){sub 3}'). On progressing from LaCrSb{sub 3} to NdCrSb{sub 3}, the 4f-band in the valence band spectra grows in intensity and shifts to higher BE. The valence band spectrum for YbCrSb{sub 3} also supports the presence of divalent ytterbium. - Graphical Abstract: In their valence band spectra, the 4f-band intensifies and shifts to higher BE on progressing from LaCrSb{sub 3} to NdCrSb{sub 3}. Highlights: Black-Right-Pointing-Pointer High-resolution core-line and valence band XPS spectra were measured for RECrSb{sub 3}. Black-Right-Pointing-Pointer Divalent Yb is present in YbCrSb{sub 3}, in contrast to trivalent RE in other members. Black-Right-Pointing-Pointer Asymmetric Cr 2p spectral lineshape confirms delocalization of Cr valence electrons. Black-Right-Pointing-Pointer Small negative Sb 3d BE shifts support assignment of anionic Sb atoms. Black-Right-Pointing-Pointer Fitted valence band spectra show shifts in the 4f band as RE is changed.

  12. Gain and tuning characteristics of mid-infrared InSb quantum dot diode lasers

    SciTech Connect (OSTI)

    Lu, Q.; Zhuang, Q.; Hayton, J.; Yin, M.; Krier, A.

    2014-07-21

    There have been relatively few reports of lasing from InSb quantum dots (QDs). In this work, type II InSb/InAs QD laser diodes emitting in the mid-infrared at 3.1??m have been demonstrated and characterized. The gain was determined to be 2.9?cm{sup ?1} per QD layer, and the waveguide loss was ?15?cm{sup ?1} at 4?K. Spontaneous emission measurements below threshold revealed a blue shift of the peak wavelength with increasing current, indicating filling of ground state heavy hole levels in the QDs. The characteristic temperature, T{sub 0}?=?101?K below 50?K, but decreased to 48?K at higher temperatures. The emission wavelength of these lasers showed first a blue shift followed by a red shift with increasing temperature. A hybrid structure was used to fabricate the laser by combining a liquid phase epitaxy grown p-InAs{sub 0.61}Sb{sub 0.13}P{sub 0.26} lower cladding layer and an upper n{sup +} InAs plasmon cladding layer which resulted in a maximum operating temperature (T{sub max}) of 120?K in pulsed mode, which is the highest reported to date.

  13. Atmospheric Chemistry Theodore S. Dibble

    E-Print Network [OSTI]

    Dibble, Theodore

    SYLLABUS FOR Atmospheric Chemistry FCH 511 Fall 2014 Theodore S. Dibble Professor of Chemistry 421 in Required Text Seinfeld, J. H. and Pandis, S. N. Atmospheric Chemistry and Physics: From Air Pollution nineteenth year at ESF, and my seventeenth year teaching FCH 511 (Atmospheric Chemistry). I have done a lot

  14. Lifetimes and eigenstates in atmospheric chemistry

    E-Print Network [OSTI]

    Prather, Michael J

    1994-01-01

    Perturbation dynamics in atmospheric chemistry. J. Geophys.isotopic variations in atmospheric chemistry. Geophys. Res.M. et al. 2001 Atmospheric chemistry and greenhouse gases (

  15. Atmospheric chemistry of an Antarctic volcanic plume

    E-Print Network [OSTI]

    2010-01-01

    L. , et al. (2010), Atmospheric chemistry results from theI. , et al. (2006), Atmospheric chemistry of a 33 – 34 hourvolcanic eruptions on atmospheric chemistry, Chem. Geol. ,

  16. Strong H...F hydrogen bonds as synthons in polymeric quantum magnets: structural, magnetic, and theoretical characterization of [Cu(HF)(pyrazine)]SbF, [CuF(HF)(FH)(pyrazine)].(SbF), and [CuAg(HF)(pyrazine)](SbF).

    SciTech Connect (OSTI)

    Manson, J. L.; Schlueter, J. A.; Funk, K. A.; Southerland, H. I.; Twamley, B.; Lancaster, T.; Blundell, S. J.; Baker, P. J.; Pratt, F. L.; Singleton, J.; McDonald, R. D.; Goddard, P. A.; Sengupta, P.; Batista, C. D.; Ding, L.; Lee, C.; Whangbo, M.-H.; Franke, I.; Cox, S.; Baines, C.; Trail, D.; Eastern Washington Univ.; Univ. of Idaho; Oxford Univ.; Rutherford Appleton Lab.; LANL; Univ. of Southern California; North Carolina State Univ.; Paul Scherrer Inst.

    2009-01-01

    Three Cu{sup 2+}-containing coordination polymers were synthesized and characterized by experimental (X-ray diffraction, magnetic susceptibility, pulsed-field magnetization, heat capacity, and muon-spin relaxation) and electronic structure studies (quantum Monte Carlo simulations and density functional theory calculations). [Cu(HF{sub 2})(pyz){sub 2}]SbF{sub 6} (pyz = pyrazine) (1a), [Cu{sub 2}F(HF)(HF{sub 2})(pyz){sub 4}](SbF{sub 6}){sub 2} (1b), and [CuAg(H{sub 3}F{sub 4})(pyz){sub 5}](SbF{sub 6}){sub 2} (2) crystallize in either tetragonal or orthorhombic space groups; their structures consist of 2D square layers of [M(pyz){sub 2}]{sup n+} that are linked in the third dimension by either HF{sub 2}{sup -} (1a and 1b) or H{sub 3}F{sub 4}{sup -} (2). The resulting 3D frameworks contain charge-balancing SbF{sub 6}{sup -} anions in every void. Compound 1b is a defective polymorph of 1a, with the difference being that 50% of the HF{sub 2}{sup -} links are broken in the former, which leads to a cooperative Jahn-Teller distortion and d{sub x{sup 2}-y{sup 2}} orbital ordering. Magnetic data for 1a and 1b reveal broad maxima in x at 12.5 and 2.6 K and long-range magnetic order below 4.3 and 1.7 K, respectively, while 2 displays negligible spin interactions owing to long and disrupted superexchange pathways. The isothermal magnetization, M(B), for 1a and 1b measured at 0.5 K reveals contrasting behaviors: 1a exhibits a concave shape as B increases to a saturation field, B{sub c}, of 37.6 T, whereas 1b presents an unusual two-step saturation in which M(B) is convex until it reaches a step near 10.8 T and then becomes concave until saturation is reached at 15.8 T. The step occurs at two-thirds of M{sub sat}, suggesting the presence of a ferrimagnetic structure. Compound 2 shows unusual hysteresis in M(B) at low temperature, although x vs T does not reveal the presence of a magnetic phase transition. Quantum Monte Carlo simulations based on an anisotropic cubic lattice were applied to the magnetic data of 1a to afford g = 2.14, J = ?13.4 K (Cu-pyz-Cu), and J = ?0.20 K (Cu?F {hor_ellipsis} H {hor_ellipsis} F?Cu), while x vs T for 1b could be well reproduced by a spin-1/2 Heisenberg uniform chain model for g = 2.127(1), J{sub 1} = ?3.81(1), and zJ{sub 2} = ?0.48(1) K, where J{sub 1} and J{sub 2} are the intra- and interchain exchange couplings, respectively, which considers the number of magnetic nearest-neighbors (z). The M(B) data for 1b could not be satisfactorily explained by the chain model, suggesting a more complex magnetic structure in the ordered state and the need for additional terms in the spin Hamiltonian. The observed variation in magnetic behaviors is driven by differences in the H {hor_ellipsis} F hydrogen-bonding motifs.

  17. Atmospheric aerosol optical property retrieval with scanning polarimeters

    E-Print Network [OSTI]

    scatter and absorb incident solar radiation and emitted infra-red radiation. Climate models simulate Mexico suspended over low altitude marine stratocumulus clouds in the Gulf of Mexico. These studies

  18. PRECISION DETERMINATION OF ATMOSPHERIC EXTINCTION AT OPTICAL AND

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to(Conference) |ofPDVGLENELG IN GALE CRATER ON MARS.GLENELG

  19. Precision Determination of Atmospheric Extinction at Optical and Near IR

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding accessusers'(x≤2) surface: A combined

  20. Precision Determination of Atmospheric Extinction at Optical and Near IR

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding accessusers'(x≤2) surface: A combinedWavelengths (Journal Article)

  1. Hierardlicsl Diagnosis V. V. Zuev Institute of Atmospheric Optics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-DoseOptions forHeavy-DutyHere�sHiddenDevelopment

  2. Optical coupler

    DOE Patents [OSTI]

    Majewski, Stanislaw; Weisenberger, Andrew G.

    2004-06-15

    In a camera or similar radiation sensitive device comprising a pixilated scintillation layer, a light guide and an array of position sensitive photomultiplier tubes, wherein there exists so-called dead space between adjacent photomultiplier tubes the improvement comprising a two part light guide comprising a first planar light spreading layer or portion having a first surface that addresses the scintillation layer and optically coupled thereto at a second surface that addresses the photomultiplier tubes, a second layer or portion comprising an array of trapezoidal light collectors defining gaps that span said dead space and are individually optically coupled to individual position sensitive photomultiplier tubes. According to a preferred embodiment, coupling of the trapezoidal light collectors to the position sensitive photomultiplier tubes is accomplished using an optical grease having about the same refractive index as the material of construction of the two part light guide.

  3. Optical memory

    DOE Patents [OSTI]

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  4. Beam Control and a New Laboratory Testbed for Adaptive Optics in a Maritime Environment

    E-Print Network [OSTI]

    in astronomical adaptive optics systems [5], [6]. Maritime beam control for shipboard applications and high energy1 Beam Control and a New Laboratory Testbed for Adaptive Optics in a Maritime Environment Capt methods for compensation of atmospheric turbulence in adaptive optics for use in a maritime environment

  5. A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS

    E-Print Network [OSTI]

    A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS MOODY T. CHU induced by atmospheric turbulence can severely de- grade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions in real time, i

  6. A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS

    E-Print Network [OSTI]

    A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS MOODY T. CHU aberrations induced by atmospheric turbulence can severely de­ grade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions in real time, i

  7. ARM - Atmospheric Heat Budget

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.TheoryTuesday, August 10, 20102016Study (CHAPS)Archive CampaignListAtmospheric Heat

  8. ARM - Atmospheric Pressure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.TheoryTuesday, August 10, 20102016Study (CHAPS)Archive CampaignListAtmospheric

  9. Atmospheric PSF Interpolation

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby a contractor ofvarDOE PAGES11 PPPL-Atmospheric PSF

  10. Microstructural evaluation of Sb-adjusted Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} buffer layer systems for IR applications

    SciTech Connect (OSTI)

    Chen, E.; Paine, D.C.; Uppal, P.; Ahearn, J.S.; Nichols, K.; Charache, G.W.

    1998-06-01

    The authors report on a transmission electron microscopy (TEM) study of Sb-adjusted quaternary Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} buffer-layers grown on <001> GaAs substrates. A series of structures were grown by MBE at 470 C that utilize a multilayer grading scheme in which the Sb content of Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} buffer-layers grown on <001> GaAs substrates. A series of structures were grown by MBe at 470 C that utilize a multilayer grading scheme in which the Sb content of Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} is successively increased in a series of 125 nm thick layers. Post growth analysis using conventional bright field and weak beam dark field imaging of these buffer layers in cross-section reveals that the interface misfit dislocations are primarily of the 60{degree} type and are distributed through out the interfaces of the buffer layer. When optimized, the authors have shown, using plan view and cross-sectional TEM, that this approach can reduce the threading defect density to below the detectability limit of TEM (< 10{sup 5}/cm{sup 2}) and preserve growth surface planarity. The Sb-graded approach was used to fabricate two 2.2 {micro}m power converter structures fabricated using InGaAs grown on Sb-based buffer layers on GaAs substrates. A microstructural and electrical characterization was performed on these device structures and the results are contrasted with a sample in which InP was selected as the substrate. Microstructure, defect density and device performance in these not-yet-optimized Sb-based buffer layers compares favorably to equivalent devices fabricated using InP substrates.

  11. An Open-path Laser Transmissometer for Atmospheric Extinction Measurements

    SciTech Connect (OSTI)

    Chandran, P. M. Satheesh; Krishnakumar, C. P.; Varma, Ravi [Department of Physics, National Institute of Technology Calicut, Calicut, Kerala 673 601 (India); Yuen, Wangki; Rood, Mark J. [Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, Urbana (United States)

    2011-10-20

    A transmissometer is an optical instrument which measures transmitted intensity of monochromatic light over a fixed pathlength. Prototype of a simple laser transmissometer has been developed for transmission (or extinction) measurements through suspended absorbers and scatterers in the atmosphere over tens of meters. Instrument consists of a continuous green diode pumped solid state laser, transmission optics, photodiode detectors and A/D data acquisition components. A modulated laser beam is transmitted and subsequently reflected and returned to the unit by a retroreflecting mirror assembly placed several tens of meters away. Results from an open-path field measurement of the instrument are described.

  12. Investigation of high hole mobility In{sub 0.41}Ga{sub 0.59}Sb/Al{sub 0.91}Ga{sub 0.09}Sb quantum well structures grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Wang, Juan; Xing, Jun-Liang; Xiang, Wei; Wang, Guo-Wei; Xu, Ying-Qiang; Ren, Zheng-Wei; Niu, Zhi-Chuan

    2014-02-03

    Modulation-doped In{sub 0.41}Ga{sub 0.59}Sb/Al{sub 0.91}Ga{sub 0.09}Sb quantum-well (QW) structures were grown by molecular beam epitaxy. Cross-sectional transmission electron microscopy and atomic force microscopy studies show high crystalline quality and smooth surface morphology. X-ray diffraction investigations confirm 1.94% compressive strain within In{sub 0.41}Ga{sub 0.59}Sb channel. High room temperature hole mobility with high sheet density of 1000 cm{sup 2}/Vs, 0.877?×?10{sup 12}/cm{sup 2}, and 965 cm{sup 2}/Vs, 1.112?×?10{sup 12}/cm{sup 2} were obtained with different doping concentrations. Temperature dependent Hall measurements show different scattering mechanisms on hole mobility at different temperature range. The sheet hole density keeps almost constantly from 300?K to 77?K. This study shows great potential of In{sub 0.41}Ga{sub 0.59}Sb/Al{sub 0.91}Ga{sub 0.09}Sb QW for high-hole-mobility device applications.

  13. Spectrometer for Sky-Scanning Sun-Tracking Atmospheric Research (4STAR): Instrument Technology

    SciTech Connect (OSTI)

    Dunagan, Stephen; Johnson, Roy; Zavaleta, Jhony; Russell, P. B.; Schmid, Beat; Flynn, Connor J.; Redemann, Jens; Shinozuka, Yohei; Livingston, J.; Segal Rozenhaimer, Michal

    2013-08-06

    The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) combines airborne sun tracking and sky scanning with diffraction spectroscopy, to improve knowledge of atmospheric constituents and their links to air-pollution/climate. Direct beam hyper-spectral measurement of optical depth improves retrievals of gas constituents and determination of aerosol properties. Sky scanning enhances retrievals of aerosol type and size distribution. 4STAR measurements will tighten the closure between satellite and ground-based measurements. 4STAR incorporates a modular sun-tracking/ sky-scanning optical head with fiber optic signal transmission to rack mounted spectrometers, permitting miniaturization of the external optical head, and future detector evolution. Technical challenges include compact optical collector design, radiometric dynamic range and stability, and broad spectral coverage. Test results establishing the performance of the instrument against the full range of operational requirements are presented, along with calibration, engineering flight test, and scientific field campaign data and results.

  14. Unusual magnetic hysteresis and the weakened transition behavior induced by Sn substitution in Mn{sub 3}SbN

    SciTech Connect (OSTI)

    Sun, Ying, E-mail: sunying@buaa.edu.cn [Center for Condensed Matter and Materials Physics, Department of Physics, Beihang University, Beijing 100191 (China); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Guo, Yanfeng; Li, Jun; Wang, Xia [Superconducting Properties Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Tsujimoto, Yoshihiro [Materials Processing Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan); Wang, Cong [Center for Condensed Matter and Materials Physics, Department of Physics, Beihang University, Beijing 100191 (China); Feng, Hai L.; Sathish, Clastin I.; Yamaura, Kazunari, E-mail: yamaura.kazunari@nims.go.jp [Superconducting Properties Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Matsushita, Yoshitaka [Analysis Station, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan)

    2014-01-28

    Substitution of Sb with Sn was achieved in ferrimagnetic antiperovskite Mn{sub 3}SbN. The experimental results indicate that with an increase in Sn concentration, the magnetization continuously decreases and the crystal structure of Mn{sub 3}Sb{sub 1-x}Sn{sub x}N changes from tetragonal to cubic phase at around x of 0.8. In the doping series, step-like anomaly in the isothermal magnetization was found and this behavior was highlighted at x?=?0.4. The anomaly could be attributed to the magnetic frustration, resulting from competition between the multiple spin configurations in the antiperovskite lattice. Meantime, H{sub c} of 18 kOe was observed at x?=?0.3, which is probably the highest among those of manganese antiperovskite materials reported so far. With increasing Sn content, the abrupt change of resistivity and the sharp peak of heat capacity in Mn{sub 3}SbN were gradually weakened. The crystal structure refinements indicate the weakened change at the magnetic transition is close related to the change of c/a ratio variation from tetragonal to cubic with Sn content. The results derived from this study indicate that the behavior of Mn{sub 3}Sb{sub 1-x}Sn{sub x}N could potentially enhance its scientific and technical applications, such as spin torque transfer and hard magnets.

  15. Sandia Energy - Quantum Optics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Quantum Optics Home Energy Research EFRCs Solid-State Lighting Science EFRC Quantum Optics Quantum OpticsTara Camacho-Lopez2015-03-30T16:37:03+00:00 Quantum Optics with a Single...

  16. Controlling SEI Formation on SnSb-Porous Carbon Nanofibers for Improved Na Ion Storage

    SciTech Connect (OSTI)

    Ji, Liwen; Gu, Meng; Shao, Yuyan; Li, Xiaolin; Engelhard, Mark H.; Arey, Bruce W.; Wang, Wei; Nie, Zimin; Xiao, Jie; Wang, Chong M.; Zhang, Jiguang; Liu, Jun

    2014-05-14

    Porous carbon nanofiber (CNF)-supported tin-antimony (SnSb) alloys is synthesized and applied as sodium ion battery anode. The chemistry and morphology of the solid electrolyte interphase (SEI) film and its correlation with the electrode performance are studied. The addition of fluoroethylene carbonate (FEC) in electrolyte significantly reduces electrolyte decomposition and creates a very thin and uniform SEI layer on the cycled electrode surface which could promote the kinetics of Na-ion migration/transportation, leading to excellent electrochemical performance.

  17. TRAC-PF1/MOD1 post-test calculations of the OECD LOFT Experiment LP-SB-3

    SciTech Connect (OSTI)

    Allen, E J; Neill, A P [UKAEA Atomic Energy Establishment, Winfrith (UK)

    1990-04-01

    Analysis of the small, cold leg break, OECD LOFT Experiment LP-SB-3 using the best-estimate computer code TRAC-PF1/MOD1 is presented. Descriptions of the LOFT facility and the LP-SB-3 experiment are given and development of the TRAC-PF1/MOD1 input model is detailed. The calculations performed in achieving the steady state conditions, from which the experiment was initiated, and the specification of experimental boundary conditions are outlined. Results of the TRAC-PF1/MOD1 calculation are found to be generally consistent with those reported, by members of the OECD LOFT Program Review Group, in the LP-SB-3 Comparison Report.'' Overall trends with respect to pressure histories, minimum primary system mass inventory and accumulator behaviour are reasonably well reproduced by TRAC-PF1/MOD1. 17 refs., 26 figs., 3 tabs.

  18. Depth-dependent magnetism in epitaxial MnSb thin films: effects of surface passivation and cleaning

    SciTech Connect (OSTI)

    Aldous J. D.; Sanchez-Hanke C.; Burrows, C.W.; Maskery, I.; Brewer, M.S.; Hase, T.P.A.; Duffy, J.A.; Lees, M. Rs; Decoster, T.; Theis, W.; Quesada, A.; Schmid, A.K.; Bell, G.R.

    2012-03-15

    Depth-dependent magnetism in MnSb(0001) epitaxial films has been studied by combining experimental methods with different surface specificities: polarized neutron reflectivity, x-ray magnetic circular dichroism (XMCD), x-ray resonant magnetic scattering and spin-polarized low energy electron microscopy (SPLEEM). A native oxide {approx}4.5 nm thick covers air-exposed samples which increases the film's coercivity. HCl etching efficiently removes this oxide and in situ surface treatment of etched samples enables surface magnetic contrast to be observed in SPLEEM. A thin Sb capping layer prevents oxidation and preserves ferromagnetism throughout the MnSb film. The interpretation of Mn L{sub 3,2} edge XMCD data is discussed.

  19. Parallel optical sampler

    DOE Patents [OSTI]

    Tauke-Pedretti, Anna; Skogen, Erik J; Vawter, Gregory A

    2014-05-20

    An optical sampler includes a first and second 1.times.n optical beam splitters splitting an input optical sampling signal and an optical analog input signal into n parallel channels, respectively, a plurality of optical delay elements providing n parallel delayed input optical sampling signals, n photodiodes converting the n parallel optical analog input signals into n respective electrical output signals, and n optical modulators modulating the input optical sampling signal or the optical analog input signal by the respective electrical output signals, and providing n successive optical samples of the optical analog input signal. A plurality of output photodiodes and eADCs convert the n successive optical samples to n successive digital samples. The optical modulator may be a photodiode interconnected Mach-Zehnder Modulator. A method of sampling the optical analog input signal is disclosed.

  20. Stable p-Type Conduction from Sb-Decorated Head-to-Head Basal Plane Inversion Domain Boundaries in ZnO Nanowires

    E-Print Network [OSTI]

    Wang, Xudong

    Stable p-Type Conduction from Sb-Decorated Head-to-Head Basal Plane Inversion Domain Boundaries of WisconsinMadison, Madison, Wisconsin 53706, United States ABSTRACT: We report that Sb-decorated head-to-head-type dopant due to low dopant solubility, native donor defects, and large acceptor ionization energies has

  1. GaSb-based Type-I QW LEDs and addressable arrays operated at wavelengths up to 3.66 m

    E-Print Network [OSTI]

    Sb-based quantum wells (QW) light emitting diodes (LED) and LED arrays operating at room temperature at wavelengths. Kipshidze, D.Westerfeld, D. Snyder, M.Johnson, G. Belenky, "GaSb-Based Type I Quantum Well Light Emitting Diode Addressable Array Operated at Wavelengths up to 3.66 µm", IEEE Photonics Technol. Lett. 21, 1087

  2. J. Phys.: Condens. Matter 8 (1996) 41894193. Printed in the UK Angle-resolved photoemission of InSb(111)2 2

    E-Print Network [OSTI]

    Kim, Sehun

    1996-01-01

    Abstract. The electronic band structure of InSb(111) along the ­ ­L 111 direction was determined using structures of GaAs(111)­2 × 2 surfaces was also carried out to determine the atomic geometry [7, 8]. However to the surface state and the resonance process of the InSb(111)­2 × 2. Investigations of electronic properties

  3. Stibioclaudetite is a new mineral species with ideal chemistry AsSbO3. The symmetry is monoclinic, P21/n, with a 5 4.5757(4) ,

    E-Print Network [OSTI]

    Downs, Robert T.

    AbstrAct Stibioclaudetite is a new mineral species with ideal chemistry AsSbO3. The symmetry, colorless transparent bladed crystals to 6 mm, bound by {010}, {110}, {111}, and {101}. The mineral of stibioclaudetite, claudetite, and leiteite are presented and compared. Stibioclaudetite AsSbO3 A New Mineral from

  4. Characterization and modeling of nanocomposite thermoelectric materials system bismuth antimony telluride ((Biy?Sb1?-?y?)2?Te3?) as a function of temperature and magnetic field

    E-Print Network [OSTI]

    Tang, Ming Y., 1979-

    2011-01-01

    This thesis looks at (BiySb1-y)2Te3 nanocomposites as an example of the currently available nano systems. In this thesis, (BiySb-y)2Te3 nanocomposites are characterized from ~325K down to ~3K. Advantages of this low ...

  5. Optical Tweezers Physics 464 Applied Optics,

    E-Print Network [OSTI]

    Optical Tweezers Physics 464 ­ Applied Optics, By Scott Cline #12;Project Topics · Brief history · Typical set-up · How they work · Common use #12;Discovery · Effects of optical scattering and gradient forces discovered by Arthur Ashkin 1970 · Method of creating an "optical trap" established in 1986

  6. Optical Packet Switching -1 Optical Networks

    E-Print Network [OSTI]

    Mellia, Marco

    Optical Packet Switching - 1 Optical Networks: from fiber transmission to photonic switching Optical Packet Switching Fabio Neri and Marco Mellia TLC Networks Group ­ Electronics Department e.mellia@polito.it ­ tel. 011 564 4173 #12;Optical Packet Switching - 2 · This work is licensed under the Creative Commons

  7. Probing Spin-Relaxation Anisotropy in 1D InSb Wires by Weak Anti-Localization

    SciTech Connect (OSTI)

    Jayathilaka, P. A. R. D.; Cairns, S.; Keay, J.; Murphy, S. Q.; Gaspe, C. K.; Mishima, T. D.; Santos, M. B. [Homer L. Dodge Department of Physics and Astronomy, Center for Semiconductor Physics in Nanostructures (C-SPIN), University of Oklahoma, Norman, OK (United States)

    2011-12-26

    Arrays of quasi-one-dimensional wires were fabricated in symmetrically doped AlInSb/InSb heterostructures to investigate the dimensional suppression of electron spin relaxation. Using weak localization analysis, it was discovered that the spin relaxation length in 300nm wide wires was enhanced by 40% relative to the two-dimensional value. Moreover, wires aligned along the <100> direction showed spin relaxation lengths {approx}30% longer than for wires aligned along <110>. This anisotropy is consistent with the additional influence of the cubic Dresselhaus interaction along the <110> direction which is predicted to be unaffected by dimensional confinement.

  8. TRAC-PF1 MOD1 post test calculations of the OECD LOFT Experiment LP-SB-1

    SciTech Connect (OSTI)

    Allen, E J [UKAEA Atomic Energy Establishment, Winfrith (UK)

    1990-04-01

    Analysis of the small, hot leg break, OECD LOFT Experiment LP-SB-1. using the best-estimate'' computer code TRAC-PF1/MOD1 is presented. Descriptions of the LOFT facility and the LP-SB-1 experiment are given and development of the TRAC-PF1/MOD1 input model is detailed. The calculations performed in achieving the steady state conditions, from which the experiment was initiated, and the specification of experimental boundary conditions are outlined. 24 refs., 66 figs., 12 tabs.

  9. Antiferromagnetism in EuCu2As2 and EuCu1.82Sb2 single crystals

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Anand, V. K.; Johnston, D. C.

    2015-05-07

    Single crystals of EuCu2As2 and EuCu2Sb2 were grown from CuAs and CuSb self-flux, respectively. The crystallographic, magnetic, thermal, and electronic transport properties of the single crystals were investigated by room-temperature x-ray diffraction (XRD), magnetic susceptibility ? versus temperature T, isothermal magnetization M versus magnetic field H, specific heat Cp(T), and electrical resistivity ?(T) measurements. EuCu2As2 crystallizes in the body-centered tetragonal ThCr2Si2-type structure (space group I4/mmm), whereas EuCu2Sb2 crystallizes in the related primitive tetragonal CaBe2Ge2-type structure (space group P4/nmm). The energy-dispersive x-ray spectroscopy and XRD data for the EuCu2Sb2 crystals showed the presence of vacancies on the Cu sites, yielding themore »actual composition EuCu1.82Sb2. The ?(T) and Cp(T) data reveal metallic character for both EuCu2As2 and EuCu1.82Sb2. Antiferromagnetic (AFM) ordering is indicated from the ?(T),Cp(T), and ?(T) data for both EuCu2As2 (TN = 17.5 K) and EuCu1.82Sb2 (TN = 5.1 K). In EuCu1.82Sb2, the ordered-state ?(T) and M(H) data suggest either a collinear A-type AFM ordering of Eu+2 spins S = 7/2 or a planar noncollinear AFM structure, with the ordered moments oriented in the tetragonal ab plane in either case. This ordered-moment orientation for the A-type AFM is consistent with calculations with magnetic dipole interactions. As a result, the anisotropic ?(T) and isothermal M(H) data for EuCu2As2, also containing Eu+2 spins S = 7/2, strongly deviate from the predictions of molecular field theory for collinear AFM ordering and the AFM structure appears to be both noncollinear and noncoplanar.« less

  10. Design and fabrication of 6.1-.ANG. family semiconductor devices using semi-insulating A1Sb substrate

    DOE Patents [OSTI]

    Sherohman, John W. (Livermore, CA); Coombs, III, Arthur W. (Patterson, CA); Yee, Jick Hong (Livermore, CA); Wu, Kuang Jen J. (Cupertino, CA)

    2007-05-29

    For the first time, an aluminum antimonide (AlSb) single crystal substrate is utilized to lattice-match to overlying semiconductor layers. The AlSb substrate establishes a new design and fabrication approach to construct high-speed, low-power electronic devices while establishing inter-device isolation. Such lattice matching between the substrate and overlying semiconductor layers minimizes the formation of defects, such as threaded dislocations, which can decrease the production yield and operational life-time of 6.1-.ANG. family heterostructure devices.

  11. Volmer–Weber InAs quantum dot formation on InP (113)B substrates under the surfactant effect of Sb

    SciTech Connect (OSTI)

    Zhao, Yu Bertru, Nicolas; Folliot, Hervé; Rohel, Tony; Mauger, Samuel J. C.; Koenraad, Paul M.

    2014-07-21

    We report on Sb surfactant growth of InAs nanostructures on GaAs{sub 0.51}Sb{sub 0.49} layers deposited on InP (001) and on (113)B oriented substrates. On the (001) orientation, the presence of Sb significantly favors the two-dimensional growth regime. Even after the deposition of 5 mono-layers of InAs, the epitaxial film remains flat and InAs/GaAs{sub 0.51}Sb{sub 0.49} type-II quantum wells are achieved. On (113)B substrates, same growth runs resulted in formation of high density InAs islands. Microscopic studies show that wetting layer is missing on (113)B substrates, and thus, a Volmer-Weber growth mode is concluded. These different behaviors are attributed to the surface energy changes induced by Sb atoms on surface.

  12. The Role of Anti-Phase Domains in InSb-Based Structures Grown on On-Axis and Off-Axis Ge Substrates

    SciTech Connect (OSTI)

    Debnath, M. C.; Mishima, T. D.; Santos, M. B.; Hossain, K.; Holland, O. W.

    2011-12-26

    Anti-phase domains form in InSb epilayers and InSb/Al{sub 0.20}In{sub 0.80}Sb single quantum wells when grown upon on-axis (001) Ge substrates by molecular beam epitaxy. Domain formation is partially suppressed through growth on Ge substrates with surfaces that are several degrees off the (001) or (211) axis. By using off-axis Ge substrates, room-temperature electron mobilities increased to {approx}60,000 cm{sup 2}/V-s and {approx}14,000 cm{sup 2}/V-s for a 4.0-{mu}m-thick InSb epilayer and a 25-nm InSb quantum well, respectively.

  13. Space Science : Atmosphere Greenhouse Effect

    E-Print Network [OSTI]

    Johnson, Robert E.

    Space Science : Atmosphere Greenhouse Effect Part-5a Solar + Earth Spectrum IR Absorbers Grey Atmosphere Greenhouse Effect #12;Radiation: Solar and Earth Surface B"(T) Planck Ideal Emission Integrate and it emits Note: heat balance Fvis( = Fout = Te 4 z #12;(simple Greenhouse cont.) 0 1 2 3 4 Ground Space Top

  14. Atmospheric science encompasses meteorology and climatology, as well as fields such as atmospheric chemistry and remote sensing.Atmospheric

    E-Print Network [OSTI]

    chemistry and remote sensing.Atmospheric scientists apply physics, mathematics, and chemistry to understandAtmospheric science encompasses meteorology and climatology, as well as fields such as atmospheric the atmosphere and its interactions with land and sea. One of the goals of atmospheric science is to understand

  15. Comparison of a TRAC calculation to the data from LSTF run SB-CL-05

    SciTech Connect (OSTI)

    Motley, F.; Schultz, R.

    1986-01-01

    Run SB-CL-05 is a 5% break in the side of the cold leg. The test results show that the core was uncovered briefly and that the rods overheated at certain core locations. Liquid holdup on the upflow side of the steam generator tubes was observed. When the loop seal cleared, the core refilled and the rods cooled. The TRAC results are in reasonable agreement with the test data, meaning that TRAC correctly predicted the major trends and phenomena. TRAC predicted the core uncovery, the resulting rod heatup, and the liquid holdup on the upflow side of the steam generator tubes correctly. The clearing of the loop seal allowed core recovery and cooled the overheated rods just as it had in the data, but TRAC predicted its occurrence 20 s late. The experimental and TRAC analysis results of run SB-CL-05 are similar to those for Semiscale Run S-UT-8. In both runs there was core uncovery, rod overheating, and steam generator liquid holdup. These results confirm scaling of these phenomena from Semiscale (1/1650) to LSTF (1/48).

  16. Decay heat removal during SB LOCA with loss of all feedwater

    SciTech Connect (OSTI)

    Prosek, A.; Mavko, B.; Petelin, S. [Jozef Stefan Institute, Ljubljana (Slovenia). Reactor Engineering Division

    1994-12-31

    The aim of this research was to investigate decay heat removal during SB LOCA with simultaneous loss of all feedwater in a two loop PWR plant. Following a SB LOCA, the major concern is to keep the core covered assuring decay heat removal from the core thereby preventing cladding damage. Analysis was performed based on the data for Krsko NPP in Slovenia. The spectrum of break sizes in the cold leg was analyzed using the RELAP5/MOD2 code. The results indicate that when the break diameter is lower than 2.5 cm, the steam generators will dry out and the primary side bleed and feed procedure should be initiated. For break diameters between 2.5 cm to 5.1 cm the decay heat can be removed by the break flow and by relieving the steam through the steam generator relief valves. For break diameters greater than 5.1 cm the break flow is sufficient to remove all dissipated decay heat.

  17. CaMn2Sb2: Spin waves on a frustrated antiferromagnetic honeycomb lattice

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    McNally, D. E.; Simonson, J. W.; Kistner-Morris, J. J.; Smith, G. J.; Hassinger, J. E.; DeBeer-Schmidt, L.; Kolesnikov, A. I.; Zaliznyak, I.; Aronson, M. C.

    2015-05-22

    We present inelastic neutron scattering measurements of the antiferromagnetic insulator CaMn2Sb2:, which consists of corrugated honeycomb layers of Mn. The dispersion of magnetic excitations has been measured along the H and L directions in reciprocal space, with a maximum excitation energy of ? 24 meV. These excitations are well described by spin waves in a Heisenberg model, including first and second neighbor exchange interactions, J1 and J2, in the Mn plane and also an exchange interaction between planes. The determined ratio J2/J1 ? 1/6 suggests that CaMn2Sb2: is the first example of a compound that lies very close to themore »mean field tricritical point, known for the classical Heisenberg model on the honeycomb lattice, where the N´eel phase and two different spiral phases coexist. The magnitude of the determined exchange interactions reveal a mean field ordering temperature ? 4 times larger than the reported N´eel temperature TN = 85 K, suggesting significant frustration arising from proximity to the tricritical point.« less

  18. Optics and Optical Engineering Program Assessment Plan Program Learning Objectives

    E-Print Network [OSTI]

    Cantlon, Jessica F.

    Optics and Optical Engineering Program Assessment Plan Program Learning, and processes that underlie optics and optical engineering. 2. Strong understanding of the fundamental science, mathematics, and processes that underlie optics and optical

  19. Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials...

    Office of Scientific and Technical Information (OSTI)

    C.; Pop, Eric; Wong, H.-S.Philip; Wuttig, Matthias; Lindenberg, Aaron M. MATSCI, OPTICS, PHYS MATSCI, OPTICS, PHYS Abstract Not Provided http:www-public.slac.stanford.edu...

  20. Optical microphone

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY)

    2000-01-11

    An optical microphone includes a laser and beam splitter cooperating therewith for splitting a laser beam into a reference beam and a signal beam. A reflecting sensor receives the signal beam and reflects it in a plurality of reflections through sound pressure waves. A photodetector receives both the reference beam and reflected signal beam for heterodyning thereof to produce an acoustic signal for the sound waves. The sound waves vary the local refractive index in the path of the signal beam which experiences a Doppler frequency shift directly analogous with the sound waves.

  1. Optical microfluidics

    SciTech Connect (OSTI)

    Kotz, K.T.; Noble, K.A.; Faris, G.W. [Molecular Physics Laboratory, SRI International, 333 Ravenswood Avenue, Menlo Park, California 94025 (United States)

    2004-09-27

    We present a method for the control of small droplets based on the thermal Marangoni effect using laser heating. With this approach, droplets covering five orders of magnitude in volume ({approx}1.7 {mu}L to 14 pL), immersed in decanol, were moved on an unmodified polystyrene surface, with speeds of up to 3 mm/s. When two droplets were brought into contact, they spontaneously fused and rapidly mixed in less than 33 ms. This optically addressed microfluidic approach has many advantages for microfluidic transport, including exceptional reconfigurability, low intersample contamination, large volume range, extremely simple substrates, no electrical connections, and ready scaling to large arrays.

  2. Optical devices

    DOE Patents [OSTI]

    Chaves, Julio C.; Falicoff, Waqidi; Minano, Juan C.; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-07-13

    An optical manifold for efficiently combining a plurality of blue LED outputs to illuminate a phosphor for a single, substantially homogeneous output, in a small, cost-effective package. Embodiments are disclosed that use a single or multiple LEDs and a remote phosphor, and an intermediate wavelength-selective filter arranged so that backscattered photoluminescence is recycled to boost the luminance and flux of the output aperture. A further aperture mask is used to boost phosphor luminance with only modest loss of luminosity. Alternative non-recycling embodiments provide blue and yellow light in collimated beams, either separately or combined into white.

  3. DIVISION OF MARINE AND ATMOSPHERIC CHEMISTRY

    E-Print Network [OSTI]

    Shyu, Mei-Ling

    DIVISION OF MARINE AND ATMOSPHERIC CHEMISTRY The missions of the Division of Marine and Atmospheric Chemistry (MAC) are to carry out broadly based research on the chemistry of the atmosphere and marine and stratosphere. Atmospheric Chemistry Research activities in atmospheric chemistry and modeling are diverse

  4. Experimental study on the emission spectra of microwave plasma at atmospheric pressure

    SciTech Connect (OSTI)

    Zhang, Boya; Wang, Qiang; Zhang, Guixin, E-mail: guixin@mail.tsinghua.edu.cn [Department of Electrical Engineering, Tsinghua University, Beijing 100084 (China); Liao, Shanshan [Department of Electrical Engineering, Tsinghua University, Beijing 100084 (China); Shenzhen Power Supply Co. Ltd., Shenzhen 518000, Guangdong (China)

    2014-01-28

    An experimental study on microwave plasma at atmospheric pressure was conducted by employing optical emission spectroscopy. Based on a microwave plasma generation device developed for nanoparticle synthesis, we studied the influence of input microwave power and gas flow rate on the optical emission behaviors and electron temperature of plasma using Ar, He, and N{sub 2} as working gas, respectively. The physics behind these behaviors was discussed. The results are useful in characterizing microwave plasma at atmospheric pressure and can be used for improving nanoparticle synthesis system for commercial use in the future.

  5. System of laser pump and synchrotron radiation probe microdiffraction to investigate optical recording process

    SciTech Connect (OSTI)

    Yasuda, Nobuhiro; Fukuyama, Yoshimitsu; Osawa, Hitoshi; Kimura, Shigeru; Ito, Kiminori; Tanaka, Yoshihito; Matsunaga, Toshiyuki; Kojima, Rie; Hisada, Kazuya; Tsuchino, Akio; Birukawa, Masahiro; Yamada, Noboru; Sekiguchi, Koji; Fujiie, Kazuhiko; Kawakubo, Osamu; Takata, Masaki

    2013-06-15

    We have developed a system of laser-pump and synchrotron radiation probe microdiffraction to investigate the phase-change process on a nanosecond time scale of Ge{sub 2}Sb{sub 2}Te{sub 5} film embedded in multi-layer structures, which corresponds to real optical recording media. The measurements were achieved by combining (i) the pump-laser system with a pulse width of 300 ps, (ii) a highly brilliant focused microbeam with wide peak-energy width ({Delta}E/E {approx} 2%) made by focusing helical undulator radiation without monochromatization, and (iii) a precise sample rotation stage to make repetitive measurements. We successfully detected a very weak time-resolved diffraction signal by using this system from 100-nm-thick Ge{sub 2}Sb{sub 2}Te{sub 5} phase-change layers. This enabled us to find the dependence of the crystal-amorphous phase change process of the Ge{sub 2}Sb{sub 2}Te{sub 5} layers on laser power.

  6. Electro-optical SLS devices for operating at new wavelength ranges

    DOE Patents [OSTI]

    Osbourn, Gordon C. (Albuquerque, NM)

    1986-01-01

    An intrinsic semiconductor electro-optical device includes a p-n junction intrinsically responsive, when cooled, to electromagnetic radiation in the wavelength range of 8-12 um. The junction consists of a strained-layer superlattice of alternating layers of two different III-V semiconductors having mismatched lattice constants when in bulk form. A first set of layers is either InAs.sub.1-x Sb.sub.x (where x is aobut 0.5 to 0.7) or In.sub.1-x Ga.sub.x As.sub.1-y Sb.sub.y (where x and y are chosen such that the bulk bandgap of the resulting layer is about the same as the minimum bandgap in the In.sub.1-x Ga.sub.x As.sub.1-y Sb.sub.y family). The second set of layers has a lattice constant larger than the lattice constant of the layers in the first set.

  7. Bias dependent dual band response from InAs/Ga,,In...Sb type II strain layer superlattice detectors

    E-Print Network [OSTI]

    New Mexico, University of

    available readout integrated circuits. © 2007 American Institute of Physics. DOI: 10.1063/1.2824819 Infrared, University of New Mexico, Albuquerque, New Mexico 87106, USA Received 10 October 2007; accepted 23 November photodetectors based on type II InAs/Ga In Sb strain layer superlattices using an nBn heterostructure design

  8. Performance of Gd-doped Ti-based Sb-SnO2 anodes for electrochemical destruction of phenol

    E-Print Network [OSTI]

    O2 anodes (Ti/SnO2-Sb), based on their electro-catalytic activities and organic oxidation rates (Ko Available online 24 October 2007 Abstract The performance of electrodes for the electro-catalytic the elec- tro-catalytic characteristics and stability of the electrodes. Some researchers have found

  9. ATMOSPHERIC CHEMISTRY - RESPONSE TO HUMAN INFLUENCE

    E-Print Network [OSTI]

    LOGAN, J; PRATHER, M; WOFSY, S; MCELROY, M

    1978-01-01

    Trans. II 70, 253. ATMOSPHERIC CHEMISTRY Clyne, M. A. A. &data for modelling atmospheric chemistry. NBS Technical NoteChem. 80, 2711. ATMOSPHERIC CHEMISTRY Sanadze, G. A. 1963 On

  10. IMPROVED QUASISTEADYSTATEAPPROXIMATION METHODS FOR ATMOSPHERIC CHEMISTRY INTEGRATION #

    E-Print Network [OSTI]

    Jay, Laurent O.

    IMPROVED QUASI­STEADY­STATE­APPROXIMATION METHODS FOR ATMOSPHERIC CHEMISTRY INTEGRATION # L. O. JAY QSSA are presented. Key words. atmospheric chemistry, sti# ordinary di#erential equations, quasi PII. S1064827595283033 1. Introduction. As our scientific understanding of atmospheric chemistry

  11. SLUDGE BATCH 7 ACCEPTANCE EVALUATION: RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB7 QUALIFICATION SAMPLE PREPARED AT SRNL

    SciTech Connect (OSTI)

    Pareizs, J.; Hay, M.

    2011-02-22

    Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch Seven (SB7) for processing in the Defense Waste Processing Facility (DWPF). The SB7 material is currently in Tank 51 being washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40. The sludge slurry in Tank 40 has already been qualified for DWPF and is currently being processed as SB6. The radionuclide concentrations were measured or estimated in the Tank 51 SB7 Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from the three liter qualification sample of Tank 51 sludge slurry (HTF-51-10-125) received on September 18, 2010. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. With consultation from the Liquid Waste Organization, the qualification sample was then modified by several washes and decants, which included addition of Pu from H Canyon and sodium nitrite per the Tank Farm corrosion control program. This final slurry now has a composition expected to be similar to that of the slurry in Tank 51 after final preparations have been made for transfer of that slurry to Tank 40. Determining the radionuclide concentrations in this Tank 51 SB7 Qualification Sample is part of the work requested in Technical Task Request (TTR) No. HLW-DWPF-TTR-2010-0031. The radionuclides included in this report are needed for the DWPF Radiological Program Evaluation, the DWPF Waste Acceptance Criteria (TSR/WAC) Evaluation, and the DWPF Solid Waste Characterization Program (TTR Task I.2). Radionuclides required to meet the Waste Acceptance Product Specifications (TTR Task III.2.) will be measured at a later date after the slurry from Tank 51 has been transferred to Tank 40. Then a sample of the as-processed SB7 will be taken and transferred to SRNL for measurement of these radionuclides. The results presented in this report are those necessary for DWPF to assess if the Tank 51 SB7 sample prepared at SRNL meets the requirements for the DWPF Radiological Program Evaluation, the DWPF Waste Acceptance Criteria evaluation, and the DWPF Solid Waste Characterization Program. Concentrations are given for thirty-four radionuclides along with total alpha and beta activity. Values for total gamma and total gamma plus beta activities are also calculated.

  12. Global atmospheric chemistry: Integrating over fractional cloud cover

    E-Print Network [OSTI]

    Neu, Jessica L; Prather, Michael J; Penner, Joyce E

    2007-01-01

    trace gases and atmospheric chemistry, in Climate Change2007 Global atmospheric chemistry: Integrating over2007), Global atmospheric chemistry: Integrating over

  13. Optical manifold

    DOE Patents [OSTI]

    Falicoff, Waqidi; Chaves, Julio C.; Minano, Juan Carlos; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-02-23

    Optical systems are described that have at least one source of a beam of blue light with divergence under 15.degree.. A phosphor emits yellow light when excited by the blue light. A collimator is disposed with the phosphor and forms a yellow beam with divergence under 15.degree.. A dichroic filter is positioned to transmit the beam of blue light to the phosphor and to reflect the beam of yellow light to an exit aperture. In different embodiments, the beams of blue and yellow light are incident upon said filter with central angles of 15.degree., 22.degree., and 45.degree.. The filter may reflect all of one polarization and part of the other polarization, and a polarization rotating retroreflector may then be provided to return the unreflected light to the filter.

  14. Water Vapour Absorption in the Clear Atmosphere of an exo-Neptune

    E-Print Network [OSTI]

    Fraine, Jonathan; Benneke, Björn; Knutson, Heather; Jordán, Andrés; Espinoza, Néstor; Madhusudhan, Nikku; Wilkins, Ashlee; Todorov, Kamen

    2014-01-01

    Transmission spectroscopy to date has detected atomic and molecular absorption in Jupiter-sized exoplanets, but intense efforts to measure molecular absorption in the atmospheres of smaller (Neptune-sized) planets during transits have revealed only featureless spectra. From this it was concluded that the majority of small, warm planets evolve to sustain high mean molecular weights, opaque clouds, or scattering hazes in their atmospheres, obscuring our ability to observe the composition of these atmospheres. Here we report observations of the transmission spectrum of HAT-P-11b (~4 Earth radii) from the optical to the infrared. We detected water vapour absorption at 1.4 micrometre wavelength. The amplitude of the water absorption (approximately 250 parts-per- million) indicates that the planetary atmosphere is predominantly clear down to ~1 mbar, and sufficiently hydrogen-rich to exhibit a large scale height. The spectrum is indicative of a planetary atmosphere with an upper limit of ~700 times the abundance of...

  15. The Influence of Chemi-ionization and Recombination Processes on Spectral Line Shapes in Stellar Atmospheres

    E-Print Network [OSTI]

    Mihajlov, Anatolij A; Sreckovic, Vladimir A; Dimitrijevic, Milan S

    2011-01-01

    In this work, the chemi-ionization processes in atom- Rydberg atom collisions, as well as the corresponding chemi-recombination processes are considered as factors of influence on the atom exited-state populations in weakly ionized layers of stellar atmospheres. The presented results are related to the photospheres of the Sun and some M red dwarfs as well as weakly ionized layers of DB white dwarfs atmospheres. It has been found that the mentioned chemi ionization/recombination processes dominate over the relevant concurrent electron-atom and electron-ion ionization and recombination process in all parts of considered stellar atmospheres. The obtained results demonstrate the fact that the considered chemi ionization/recombination processes must have a very significant influence on the optical properties of the stellar atmospheres. Thus, it is shown that these processes and their importance for non-local thermodynamic equilibrium (non-LTE) modeling of the solar atmospheres should be investigated further.

  16. Non-Ideal p-n junction Diode of Sb{sub x}Se{sub 1-x}(x = 0.4, 0.5, 0.6, 0.7) Thin Films

    SciTech Connect (OSTI)

    Mustafa, Falah I. [Solar Energy Research Center, Renewable Energy Directorate, Ministry of Science and Technology, Baghdad (Iraq); Gupta, Shikha; Goyal, N.; Tripathi, S. K. [Department of Physics, Panjab University, Chandigarh -160014 (India)

    2011-12-12

    We have made diodes consisting of the same alloy i.e. Sb{sub x}Se{sub 1-x}(x = 0.4, 0.5, 0.6 and 0.7), but change the concentration of Sb metal from 40% to 70% atomic weight percentage. It is observed from the Hall measurements that the nature of charge carriers have changed from p- to n-type at x = 0.6 for Sb{sub x}Se{sub 1-x}. We have measured I-V characteristics of four p-n junction diodes i.e. p-Sb{sub 2}Se{sub 3}/n-Sb{sub 3}Se{sub 2}, p-Sb{sub 2}Se{sub 3}/n-Sb{sub 7}Se{sub 3}, p-SbSe/n-Sb{sub 3}Se{sub 2}, p-SbSe/n-Sb{sub 7}Se{sub 3}. From the I-V plots we have calculated the parameters as built-in voltage (V{sub bi}), forward resistance (R{sub f}), ideal factor (n), saturation current (I{sub o}), breakdown current (I{sub Bd}) and breakdown voltage (V{sub Bd}).

  17. Infrared Observations of Exoplanet Atmospheres

    E-Print Network [OSTI]

    Crossfield, Ian James Mills

    2012-01-01

    However, atmospheres of cool planets can still be studiedvia outgassing as the planet cools (Rogers & Seager 2010).at low resolution) and the cool, low-mass planet GJ 1214b (

  18. Composition and Reactions of Atmospheric Aerosol Particles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion...

  19. The SLS optics beamline

    E-Print Network [OSTI]

    2006-01-01

    The SLS Optics Beamline U. Flechsig ? , R. Abela ? , R.in the ?eld of x-ray optics and synchrotron radiation in-radiation, beamline optics, channel cut monochromator,

  20. SURFACE NONLINEAR OPTICS

    E-Print Network [OSTI]

    Shen, Y.R.

    2010-01-01

    B. de Castro, and Y. R. Shen, Optics Lett. i, 393 See, for3, 1980 SURFACE NONLINEAR OPTICS Y.R. Shen, C.K. Chen, andde Janiero SURFRACE NONLINEAR OPTICS Y. R. Shen, C. K. Chen,

  1. NONLINEAR OPTICS AT INTERFACES

    E-Print Network [OSTI]

    Chen, Chenson K.

    2010-01-01

    N. Bloembergen, Nonlinear Optics (W. A. Benjamin, 1977) p.Research Division NONLINEAR OPTICS AT INTERFACES Chenson K.ED LBL-12084 NONLINEAR OPTICS AT INTERFACES Chenson K. Chen

  2. Laser Atmospheric Studies with VERITAS

    E-Print Network [OSTI]

    C. M. Hui; for the VERITAS collaboration

    2007-09-25

    As a calibrated laser pulse propagates through the atmosphere, the amount of Rayleigh-scattered light arriving at the VERITAS telescopes can be calculated precisely. This technique was originally developed for the absolute calibration of ultra-high-energy cosmic-ray fluorescence telescopes but is also applicable to imaging atmospheric Cherenkov telescopes (IACTs). In this paper, we present two nights of laser data taken with the laser at various distances away from the VERITAS telescopes and compare it to Rayleigh scattering simulations.

  3. Atmospheric science and power production

    SciTech Connect (OSTI)

    Randerson, D.

    1984-07-01

    This is the third in a series of scientific publications sponsored by the US Atomic Energy Commission and the two later organizations, the US Energy Research and Development Adminstration, and the US Department of Energy. The first book, Meteorology and Atomic Energy, was published in 1955; the second, in 1968. The present volume is designed to update and to expand upon many of the important concepts presented previously. However, the present edition draws heavily on recent contributions made by atmospheric science to the analysis of air quality and on results originating from research conducted and completed in the 1970s. Special emphasis is placed on how atmospheric science can contribute to solving problems relating to the fate of combustion products released into the atmosphere. The framework of this book is built around the concept of air-quality modeling. Fundamentals are addressed first to equip the reader with basic background information and to focus on available meteorological instrumentation and to emphasize the importance of data management procedures. Atmospheric physics and field experiments are described in detail to provide an overview of atmospheric boundary layer processes, of how air flows around obstacles, and of the mechanism of plume rise. Atmospheric chemistry and removal processes are also detailed to provide fundamental knowledge on how gases and particulate matter can be transformed while in the atmosphere and how they can be removed from the atmosphere. The book closes with a review of how air-quality models are being applied to solve a wide variety of problems. Separate analytics have been prepared for each chapter.

  4. NGC 1266: Characterization of the Nuclear Molecular Gas in an Unusual SB0 Galaxy

    E-Print Network [OSTI]

    Glenn, Jason; Maloney, Philip R; Kamenetzky, Julia R

    2015-01-01

    With a substantial nuclear molecular gas reservoir and broad, high-velocity CO molecular line wings previously interpreted as an outflow, NGC 1266 is a rare SB$0$ galaxy. Previous analyses of interferometry, spectrally resolved low-$J$ CO emission lines, and unresolved high-$J$ emission lines have established basic properties of the molecular gas and the likely presence of an AGN. Here, new spectrally resolved CO $J = 5 - 4$ to $J = 8 - 7$ lines from {\\it Herschel Space Observatory} HIFI observations are combined with ground-based observations and high-$J$ {\\it Herschel} SPIRE observations to decompose the nuclear and putative outflow velocity components and to model the molecular gas to quantify its properties. Details of the modeling and results are described, with comparisons to previous results and exploration of the implications for the gas excitation mechanisms. Among the findings, like for other galaxies, the nuclear and putative outflow molecular gas are well represented by components that are cool ($...

  5. RELAP5 simulation of SB LOCA in a VVER 440 model

    SciTech Connect (OSTI)

    Parzer, I.; Mavko, B.; Petelin, S.

    1992-01-01

    The VVER-440-type plants differ considerably from western-type pressurized water reactors (PWR). The two main distinguishing characteristics are horizontal steam generators and loop seals in both hot and cold legs, which are lately a great safety concern worldwide. In 1987, the International Atomic Energy Agency (IAEA) organized and sponsored one of the tests performed on the Hungarian PMK-NVH test facility and called it IAEA-SPE-2. The test was chosen from a wider test matrix performed to investigate emergency core cooling system capability in VVER-440 plants for a small-break loss-of-coolant accident (SB LOCA). PMK-NVA is a one-loop, full-height, full-pressure model of the Hungarian Paks nuclear power plant, type VVER-440, Soviet production. The facility power level is 100%, according to the 1:2070 scaling factor.

  6. Evaluation of electron mobility in InSb quantum wells by means of percentage-impact

    SciTech Connect (OSTI)

    Mishima, T. D.; Edirisooriya, M.; Santos, M. B. [Homer L. Dodge Department of Physics and Astronomy, and Center for Semiconductor Physics in Nanostructure, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States)

    2014-05-15

    In order to quantitatively analyze the contribution of each scattering factor toward the total carrier mobility, we use a new convenient figure-of-merit, named a percentage impact. The mobility limit due to a scattering factor, which is widely used to summarize a scattering analysis, has its own advantage. However, a mobility limit is not quite appropriate for the above purpose. A comprehensive understanding of the difference in contribution among many scattering factors toward the total carrier mobility can be obtained by evaluating percentage impacts of scattering factors, which can be straightforwardly calculated from their mobility limits and the total mobility. Our percentage impact analysis shows that threading dislocation is one of the dominant scattering factors for the electron transport in InSb quantum wells at room temperature.

  7. Chapter 2 Diffractive Optics

    E-Print Network [OSTI]

    2010-09-14

    Diffractive optics is an emerging technology with many applications. Some of the important applications include the design and fabrication of optical elements ...

  8. Advanced Optical Technologies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    laser. Today, the optical team designs and fabricates a variety of custom diffractive optics for researchers worldwide. Included are multilayer dielectric and gold-overcoated...

  9. Planar micro-optic solar concentration

    E-Print Network [OSTI]

    Karp, Jason Harris

    2010-01-01

    Planar Micro-Optic Solar Collectors," Optics for Solarin planar micro-optic solar collectors,” Optics Express, (inin planar micro-optic solar collectors,” Optics Express (in

  10. ARESE (ARM Enhanced Shortwave Experiment) Science Plan [Atmospheric Radiation Program

    SciTech Connect (OSTI)

    Valero, F.P.J.; Schwartz, S.E.; Cess, R.D.; Ramanathan, V.; Collins, W.D.; Minnis, P.; Ackerman, T.P.; Vitko, J.; Tooman, T.P.

    1995-09-27

    Several recent studies have indicated that cloudy atmospheres may absorb significantly more solar radiation than currently predicted by models. The magnitude of this excess atmospheric absorption, is about 50% more than currently predicted and would have major impact on our understanding of atmospheric heating. Incorporation of this excess heating into existing general circulation models also appears to ameliorate some significant shortcomings of these models, most notably a tendency to overpredict the amount of radiant energy going into the oceans and to underpredict the tropopause temperature. However, some earlier studies do not show this excess absorption and an underlying physical mechanism that would give rise to such absorption has yet to be defined. Given the importance of this issue, the Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) program is sponsoring the ARM Enhanced Shortwave Experiment (ARESE) to study the absorption of solar radiation by clear and cloudy atmospheres. The experimental results will be compared with model calculations. Measurements will be conducted using three aircraft platforms (ARM-UAV Egrett, NASA ER-2, and an instrumented Twin Otter), as well as satellites and the ARM central and extended facilities in North Central Oklahoma. The project will occur over a four week period beginning in late September, 1995. Spectral broadband, partial bandpass, and narrow bandpass (10nm) solar radiative fluxes will be measured at different altitudes and at the surface with the objective to determine directly the magnitude and spectral characteristics of the absorption of shortwave radiation by the atmosphere (clear and cloudy). Narrow spectral channels selected to coincide with absorption by liquid water and ice will help in identifying the process of absorption of radiation. Additionally, information such as water vapor profiles, aerosol optical depths, cloud structure and ozone profiles, needed to use as input in radiative transfer calculations, will be acquired using the aircraft and surface facilities available to ARESE. This document outlines the scientific approach and measurement requirements of the project.

  11. Chemistry of Atmospheric Brown Carbon Alexander Laskin,*,

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    Chemistry of Atmospheric Brown Carbon Alexander Laskin,*, Julia Laskin,*, and Sergey A. Nizkorodov fraction of atmospheric aerosol and has profound effects on air quality, atmospheric chemistry, and climate of radiation through Earth's atmosphere. The cloud albedo effect, Special Issue: 2015 Chemistry in Climate

  12. Using observations of deep convective systems to constrain atmospheric column absorption of solar radiation in the

    E-Print Network [OSTI]

    Dong, Xiquan

    column absorption of solar radiation (Acol) is a fundamental part of the Earth's energy cycle.e., the Acol values at both regions converge to the same value ($0.27 of the total incoming solar radiation to constrain atmospheric column absorption of solar radiation in the optically thick limit, J. Geophys. Res

  13. Habitability of waterworlds: runaway greenhouses, atmospheric expansion and multiple climate states of pure water atmospheres

    E-Print Network [OSTI]

    Goldblatt, Colin

    2015-01-01

    There are four different stable climate states for pure water atmospheres, as might exist on so-called "waterworlds". I map these as a function of solar constant for planets ranging in size from Mars size to 10 Earth-mass. The states are: globally ice covered (Ts< 245K), cold and damp (270 < Ts< 290K), hot and moist (350< Ts< 550K) and very hot and dry (Ts< 900K). No stable climate exists for 290< Ts < 350K or 550 < Ts < 900K. The union of hot moist and cold damp climates describe the liquid water habitable zone, the width and location of which depends on planet mass. At each solar constant, two or three different climate states are stable. This is a consequence of strong non-linearities in both thermal emission and the net absorption of sunlight. Across the range of planet sizes, I account for the atmospheres expanding to high altitudes as they warm. The emitting and absorbing surfaces (optical depth of unity) move to high altitude, making their area larger than the planet surfa...

  14. Simulation of Crystallization in Ge[subscript 2]Sb[subscript 2]Te[subscript 2]: A Memory Effect in the Canonical Phase-Change Material

    E-Print Network [OSTI]

    Akola, J.

    Crystallization of amorphous Ge[subscript 2]Sb[subscript 2]Te[subscript 5] (GST) has been studied using four extensive (460 atoms, up to 4 ns) density functional/molecular dynamics simulations at 600 K. This phase change ...

  15. Electronic structure and thermoelectric performance of Zintl compound Sr{sub 3}GaSb{sub 3}: A first-principles study

    SciTech Connect (OSTI)

    Feng Shi, Qing; Li Yan, Yu; Xu Wang, Yuan, E-mail: wangyx@henu.edu.cn [Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004 (China)

    2014-01-06

    By using first-principles method and Boltzmann theory, we simulated the thermoelectric transport properties of p-type and n-type Sr{sub 3}GaSb{sub 3}. It is found that the thermoelectric figure-of merit (ZT) of n-type Sr{sub 3}GaSb{sub 3} is probably better than that of p-type, mainly due to its large band degeneracy. Moreover, a high ZT value of 1.74 at 850?K can be achieved for n-type Sr{sub 3}GaSb{sub 3} along the yy direction, corresponding to the carrier concentration 3.5?×?10{sup 20}?e cm{sup ?3}. We propose that the high ZT value of experimentally synthesized p-type Sr{sub 3}GaSb{sub 3} is originated from appearing of the larger number of band valley on the top of valence bands.

  16. Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system

    DOE Patents [OSTI]

    Moon, Ronald L. (Palo Alto, CA)

    1981-01-01

    Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5.mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photovoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of the growing layer.

  17. Influence of in-situ annealing ambient on p-type conduction in dual ion beam sputtered Sb-doped ZnO thin films

    SciTech Connect (OSTI)

    Pandey, Sushil Kumar; Kumar Pandey, Saurabh; Awasthi, Vishnu; Mukherjee, Shaibal; Gupta, M.; Deshpande, U. P.

    2013-08-12

    Sb-doped ZnO (SZO) films were deposited on c-plane sapphire substrates by dual ion beam sputtering deposition system and subsequently annealed in-situ in vacuum and in various proportions of O{sub 2}/(O{sub 2} + N{sub 2})% from 0% (N{sub 2}) to 100% (O{sub 2}). Hall measurements established all SZO films were p-type, as was also confirmed by typical diode-like rectifying current-voltage characteristics from p-ZnO/n-ZnO homojunction. SZO films annealed in O{sub 2} ambient exhibited higher hole concentration as compared with films annealed in vacuum or N{sub 2} ambient. X-ray photoelectron spectroscopic analysis confirmed that Sb{sup 5+} states were more preferable in comparison to Sb{sup 3+} states for acceptor-like Sb{sub Zn}-2V{sub Zn} complex formation in SZO films.

  18. Lattice constant grading in the Al.sub.y Ga.sub.1-y As.sub.1-x Sb.sub.x alloy system

    DOE Patents [OSTI]

    Moon, Ronald L. (Palo Alto, CA)

    1980-01-01

    Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5 .mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photolvoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of growing layer.

  19. LABORATORY I: GEOMETRIC OPTICS

    E-Print Network [OSTI]

    Minnesota, University of

    Lab I - 1 LABORATORY I: GEOMETRIC OPTICS In this lab, you will solve several problems related to the formation of optical images. Most of us have a great deal of experience with the formation of optical images this laboratory, you should be able to: · Describe features of real optical systems in terms of ray diagrams

  20. Cumulant expansions for atmospheric flows

    E-Print Network [OSTI]

    Ait-Chaalal, Farid; Meyer, Bettina; Marston, J B

    2015-01-01

    The equations governing atmospheric flows are nonlinear, and consequently the hierarchy of cumulant equations is not closed. But because atmospheric flows are inhomogeneous and anisotropic, the nonlinearity may manifests itself only weakly through interactions of mean fields with disturbances such as thermals or eddies. In such situations, truncations of the hierarchy of cumulant equations hold promise as a closure strategy. We review how truncations at second order can be used to model and elucidate the dynamics of turbulent atmospheric flows. Two examples are considered. First, we study the growth of a dry convective boundary layer, which is heated from below, leading to turbulent upward energy transport and growth of the boundary layer. We demonstrate that a quasilinear truncation of the equations of motion, in which interactions of disturbances among each other are neglected but interactions with mean fields are taken into account, can successfully capture the growth of the convective boundary layer. Seco...

  1. Optical XOR gate

    DOE Patents [OSTI]

    Vawter, G. Allen

    2013-11-12

    An optical XOR gate is formed as a photonic integrated circuit (PIC) from two sets of optical waveguide devices on a substrate, with each set of the optical waveguide devices including an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical XOR gate utilizes two digital optical inputs to generate an XOR function digital optical output. The optical XOR gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 .mu.m.

  2. Effect of fog on free-space optical links employing imaging receivers

    E-Print Network [OSTI]

    Kahn, Joseph M.

    Effect of fog on free-space optical links employing imaging receivers Reza Nasiri Mahalati in the presence of misalignment and atmospheric effects, such as haze, fog or rain. We present a detailed that image blooming dominates over attenuation, except under medium-to-heavy fog conditions. ©2012 Optical

  3. High resolution transmission spectroscopy as a diagnostic for Jovian exoplanet atmospheres: constraints from theoretical models

    SciTech Connect (OSTI)

    Kempton, Eliza M.-R.; Perna, Rosalba; Heng, Kevin

    2014-11-01

    We present high resolution transmission spectra of giant planet atmospheres from a coupled three-dimensional (3D) atmospheric dynamics and transmission spectrum model that includes Doppler shifts which arise from winds and planetary motion. We model Jovian planets covering more than two orders of magnitude in incident flux, corresponding to planets with 0.9-55 day orbital periods around solar-type stars. The results of our 3D dynamical models reveal certain aspects of high resolution transmission spectra that are not present in simple one-dimensional (1D) models. We find that the hottest planets experience strong substellar to anti-stellar (SSAS) winds, resulting in transmission spectra with net blueshifts of up to 3 km s{sup –1}, whereas less irradiated planets show almost no net Doppler shifts. We find only minor differences between transmission spectra for atmospheres with temperature inversions and those without. Compared to 1D models, peak line strengths are significantly reduced for the hottest atmospheres owing to Doppler broadening from a combination of rotation (which is faster for close-in planets under the assumption of tidal locking) and atmospheric winds. Finally, high resolution transmission spectra may be useful in studying the atmospheres of exoplanets with optically thick clouds since line cores for very strong transitions should remain optically thick to very high altitude. High resolution transmission spectra are an excellent observational test for the validity of 3D atmospheric dynamics models, because they provide a direct probe of wind structures and heat circulation. Ground-based exoplanet spectroscopy is currently on the verge of being able to verify some of our modeling predictions, most notably the dependence of SSAS winds on insolation. We caution that interpretation of high resolution transmission spectra based on 1D atmospheric models may be inadequate, as 3D atmospheric motions can produce a noticeable effect on the absorption signatures.

  4. Atomistic modeling and HAADF investigations of misfit and threading dislocations in GaSb/GaAs hetero-structures for applications in high electron mobility transistors

    SciTech Connect (OSTI)

    Ruterana, Pierre Wang, Yi Chen, Jun Chauvat, Marie-Pierre; El Kazzi, S.; Deplanque, L.; Wallart, X.

    2014-10-06

    A detailed investigation on the misfit and threading dislocations at GaSb/GaAs interface has been carried out using molecular dynamics simulation and quantitative electron microscopy techniques. The sources and propagation of misfit dislocations have been elucidated. The nature and formation mechanisms of the misfit dislocations as well as the role of Sb on the stability of the Lomer configuration have been explained.

  5. Evaluation of Optical Magnitude of Deep Space Spacecraft

    E-Print Network [OSTI]

    Liu Wei; Tang Zheng-Hong; Li Yong-Da

    2007-12-10

    Optical-electric technology can measure the tangential position and velocity of spacecraft. To know the feasibility of the use of optical-electric technology, it is necessary to estimate the magnitude of spacecraft first. Since the spacecrafts are non-self-illumination objects, the estimation formulas of the optical magnitude of spacecraft is constructed according to the radiation theory and the extra-atmospheric radiant emittance of the Sun in the visible light wave band. Taking Chang'e-1 as an example, the magnitude of it in different situations is calculated.

  6. Observations of atmospheric tides on Mars at the season and latitude of the Phoenix atmospheric entry

    E-Print Network [OSTI]

    Withers, Paul

    Observations of atmospheric tides on Mars at the season and latitude of the Phoenix atmospheric atmospheric entry of NASA's Phoenix Mars probe using Phoenix Atmospheric Structure Experiment (ASE) data atmospheric entry, Geophys. Res. Lett., 37, L24204, doi:10.1029/2010GL045382. 1. Introduction [2] Phoenix

  7. Effect of antimony on the deep-level traps in GaInNAsSb thin films

    SciTech Connect (OSTI)

    Islam, Muhammad Monirul Miyashita, Naoya; Ahsan, Nazmul; Okada, Yoshitaka; Sakurai, Takeaki; Akimoto, Katsuhiro

    2014-09-15

    Admittance spectroscopy has been performed to investigate the effect of antimony (Sb) on GaInNAs material in relation to the deep-level defects in this material. Two electron traps, E1 and E2 at an energy level 0.12 and 0.41?eV below the conduction band (E{sub C}), respectively, were found in undoped GaInNAs. Bias-voltage dependent admittance confirmed that E1 is an interface-type defect being spatially localized at the GaInNAs/GaAs interface, while E2 is a bulk-type defect located around mid-gap of GaInNAs layer. Introduction of Sb improved the material quality which was evident from the reduction of both the interface and bulk-type defects.

  8. Phase transitions in double perovskite Sr{sub 2}ScSbO{sub 6}: An Ab-initio study

    SciTech Connect (OSTI)

    Ray, Rajyavardhan; Kumar, Uday; Sinha, T. P.

    2014-04-24

    First Principles study of the electronic properties of recently synthesized double perovskite Sr{sub 2}ScSbO{sub 6} have been performed using density functional theory. With increasing temperature, the Sr compound undergoes three structural phase transitions at 400K, 550K and 650K approximately, leading to the following sequence of phases: P21/n ? I2/m ? I4/m ? Fm-3m. Starting from the monoclinic phase P21/n at room temperature, resulting from the Sc/Sb ordering, the electronic structure for the tetragonal I4/m at 613K and cubic Fm-3m for T?660K has been studied in terms of the density of states and band-structure. Presence of large band gap, both direct and indirect, has been reported and analyzed.

  9. Methods for chemical recovery of non-carrier-added radioactive tin from irradiated intermetallic Ti-Sb targets

    DOE Patents [OSTI]

    Lapshina, Elena V. (Troitsk, RU); Zhuikov, Boris L. (Troitsk, RU); Srivastava, Suresh C. (Setauket, NY); Ermolaev, Stanislav V. (Obninsk, RU); Togaeva, Natalia R. (Obninsk, RU)

    2012-01-17

    The invention provides a method of chemical recovery of no-carrier-added radioactive tin (NCA radiotin) from intermetallide TiSb irradiated with accelerated charged particles. An irradiated sample of TiSb can be dissolved in acidic solutions. Antimony can be removed from the solution by extraction with dibutyl ether. Titanium in the form of peroxide can be separated from tin using chromatography on strong anion-exchange resin. In another embodiment NCA radiotin can be separated from iodide solution containing titanium by extraction with benzene, toluene or chloroform. NCA radiotin can be finally purified from the remaining antimony and other impurities using chromatography on silica gel. NCA tin-117m can be obtained from this process. NCA tin-117m can be used for labeling organic compounds and biological objects to be applied in medicine for imaging and therapy of various diseases.

  10. USING OPTICAL COHERENCE TOMOGRAPHY TO EXAMINE THE SUBSURFACE MORPHOLOGY OF

    E-Print Network [OSTI]

    Barton, Jennifer K.

    ), a new method for ceramics research, is a non-destructive, three-dimensional tomography system, which;However, optical coherence tomography (OCT) provides a non-destructive, three-dimensional technique and atmosphere controlled, cooling rates modified, additive experimental testing and other parameters measured

  11. New method for atmospheric calibration at the Pierre Auger Observatory using FRAM, a robotic astronomical telescope

    E-Print Network [OSTI]

    Segev BenZvi; Martina Bohacova; Brian Connolly; Jiri Grygar; Miroslav Hrabovsky; Tatiana Karova; Dusan Mandat; Petr Necesal; Dalibor Nosek; Libor Nozka; Miroslav Palatka; Miroslav Pech; Michael Prouza; Jan Ridky; Petr Schovanek; Radomir Smida; Petr Travnicek; Primo Vitale; Stefan Westerhoff; for the Pierre Auger Collaboration

    2007-06-12

    FRAM - F/(Ph)otometric Robotic Atmospheric Monitor is the latest addition to the atmospheric monitoring instruments of the Pierre Auger Observatory. An optical telescope equipped with CCD camera and photometer, it automatically observes a set of selected standard stars and a calibrated terrestrial source. Primarily, the wavelength dependence of the attenuation is derived and the comparison between its vertical values (for stars) and horizontal values (for the terrestrial source) is made. Further, the integral vertical aerosol optical depth can be obtained. A secondary program of the instrument, the detection of optical counterparts of gamma-ray bursts, has already proven successful. The hardware setup, software system, data taking procedures, and first analysis results are described in this paper.

  12. Pulsed atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1992-08-01

    The general specifications for a Pulsed Atmospheric Fluidized Bed Combustor Design Report (PAFBC) plant are presented. The design tasks for the PAFBC are described in the following areas: Coal/Limestone preparation and feed system; pulse combustor; fluidized bed; boiler parts; and ash handling system.

  13. Critical phenomena in atmospheric precipitation

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS Critical phenomena in atmospheric precipitation OLE PETERS1,2,3 * AND J. DAVID NEELIN3 1 convection and precipitation (the order parameter)--with correlated regions on scales of tens to hundreds the climatological mean by an order of magnitude or more. Moist convection and the accompanying precipitation have

  14. Synthesis of nanocrystalline thin films of gold on the surface of GaSb by swift heavy ion

    SciTech Connect (OSTI)

    Jadhav, Vidya; Dubey, S. K.; Yadav, A. D.; Singh, A.

    2013-02-05

    Thin films of gold ({approx}100 nm thick) were deposited on p-type GaSb substrates. These samples were irradiated with 100 MeV Fe{sup 7+}ions for the fluence of 1 Multiplication-Sign 10{sup 13} and 1 Multiplication-Sign 10{sup 14} ions cm{sup -2}. After irradiation, samples were characterized using AFM, UV-VIS -NIR, X-Ray Diffraction techniques. AFM studies showed the presence of clusters on the surface of GaSb. R.M.S. roughness of the sample was found to increase w.r.t ion fluence. Absorption coefficient obtained from the Ultra violet - Visible NIR (UV-VIS -NIR) spectra of the samples irradiated with various fluences compared with non irradiated GaSb. The annealing experiment showed a significant improvement in the absorption coefficient after rapid thermal annealing at temperature of 400 Degree-Sign C. X-Ray Diffraction study reveals different orientations of Au film.

  15. Electron interactions and Dirac fermions in graphene-Ge{sub 2}Sb{sub 2}Te{sub 5} superlattices

    SciTech Connect (OSTI)

    Sa, Baisheng [College of Materials, and Collaborative Innovation Center of Chemistry for Energy Materials, Xiamen University, Xiamen 361005 (China); Sun, Zhimei, E-mail: zmsun@buaa.edu.cn [School of Materials Science and Engineering, and Center for Integrated Computational Materials Engineering, International Research Institute for Multidisciplinary Science, Beihang University, Beijing 100191 (China)

    2014-06-21

    Graphene based superlattices have been attracted worldwide interest due to the combined properties of the graphene Dirac cone feature and all kinds of advanced functional materials. In this work, we proposed a novel series of graphene-Ge{sub 2}Sb{sub 2}Te{sub 5} superlattices based on the density functional theory calculations. We demonstrated the stability in terms of energy and lattice dynamics for such kind of artificial materials. The analysis of the electronic structures unravels the gap opening nature at Dirac cone of the insert graphene layer. The Dirac fermions in the graphene layers are strongly affected by the electron spin orbital coupling in the Ge{sub 2}Sb{sub 2}Te{sub 5} layers. The present results show the possible application in phase-change data storage of such kind of superlattice materials, where the Ge{sub 2}Sb{sub 2}Te{sub 5} layers exhibit as the phase-change data storage media and the graphene layer works as the electrode, probe, and heat conductor.

  16. Atomic-resolution study of polarity reversal in GaSb grown on Si by scanning transmission electron microscopy

    SciTech Connect (OSTI)

    Hosseini Vajargah, S.; Woo, S. Y.; Botton, G. A.; Ghanad-Tavakoli, S.; Kleiman, R. N.; Preston, J. S.

    2012-11-01

    The atomic-resolved reversal of the polarity across an antiphase boundary (APB) was observed in GaSb films grown on Si by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The investigation of the interface structure at the origin of the APB reveals that coalescence of two domains with Ga-prelayer and Sb-prelayer causes the sublattice reversal. The local strain and lattice rotation distributions of the APB, attributed to the discordant bonding length at the APB with the surrounding GaSb lattice, were further studied using the geometric phase analysis technique. The crystallographic characteristics of the APBs and their interaction with other planar defects were observed with HAADF-STEM. The quantitative agreement between experimental and simulated images confirms the observed polarities in the acquired HAADF-STEM data. The self-annihilation mechanism of the APBs is addressed based on the rotation induced by anti-site bonds and APBs' faceting.

  17. Argon-ion-induced formation of nanoporous GaSb layer: Microstructure, infrared luminescence, and vibrational properties

    SciTech Connect (OSTI)

    Datta, D. P.; Som, T., E-mail: tsom@iopb.res.in [SUNAG Laboratory, Institute of Physics, Bhubaneswar, Odisha 751 005 (India); Kanjilal, A. [Department of Physics, Shiv Nadar University, Uttar Pradesh 201 314 (India); Satpati, B. [Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India); Dhara, S. [Surface and Nanoscience Division, Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Das, T. D. [Department of Electronic Science, University of Calcutta, APC Road, Kolkata 700 009 (India); Kanjilal, D. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067 (India)

    2014-07-21

    Room temperature implantation of 60?keV Ar{sup +}-ions in GaSb to the fluences of 7?×?10{sup 16} to 3?×?10{sup 18} ions cm{sup ?2} is carried out at two incidence angles, viz 0° and 60°, leading to formation of a nanoporous layer. As the ion fluence increases, patches grow on the porous layer under normal ion implantation, whereas the porous layer gradually becomes embedded under a rough top surface for oblique incidence of ions. Grazing incidence x-ray diffraction and cross-sectional transmission electron microscopy studies reveal the existence of nanocrystallites embedded in the ion-beam amorphized GaSb matrix up to the highest fluence used in our experiment. Oxidation of the nanoporous layers becomes obvious from x-ray photoelectron spectroscopy and Raman mapping. The correlation of ion-beam induced structural modification with photoluminescence signals in the infrared region has further been studied, showing defect induced emission of additional peaks near the band edge of GaSb.

  18. 60 keV Ar?-ion induced modification of microstructural, compositional, and vibrational properties of InSb

    SciTech Connect (OSTI)

    Datta, D. P.; Garg, S. K.; Som, T., E-mail: tsom@iopb.res.in [SUNAG Laboratory, Institute of Physics, Bhubaneswar, Odisha 751005 (India); Satpati, B. [Surface Physics and Materials Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Sahoo, P. K. [School of Physical Sciences, National Institute of Science Education and Research, Bhubaneswar 751005, Odisha (India); Kanjilal, A. [Department of Physics, Shiv Nadar University, Uttar Pradesh 203207 (India); Dhara, S. [Surface and Nanoscience Division, Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Kanjilal, D. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

    2014-10-14

    Room temperature irradiation of InSb(111) by 60 keV Ar?-ions at normal (0°) and oblique (60°) angles of incidence led to the formation of nanoporous structure in the high fluence regime of 1×10¹? to 3×10¹? ions cm?². While a porous layer comprising of a network of interconnected nanofibers was generated by normal ion incidence, evolution of plate-like structures was observed for obliquely incident ions. Systematic studies of composition and structure using energy dispersive x-ray spectroscopy, Raman spectroscopy, x-ray photoelectron spectroscopy, Raman mapping, grazing incidence x-ray diffraction, and cross-sectional transmission electron microscopy revealed a high degree of oxidation of the ion-induced microstructures with the presence of In?O? and Sb?O? phases and presence of nanocrystallites within the nanoporous structures. The observed structural evolution was understood in terms of processes driven by ion-induced defect accumulation within InSb.

  19. Latching micro optical switch

    DOE Patents [OSTI]

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

    An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.

  20. Influence of interstitial Mn on magnetism in room-temperature ferromagnet Mn(1+delta)Sb

    SciTech Connect (OSTI)

    Taylor, Alice E [ORNL; Berlijn, Tom [ORNL; Hahn, Steven E [ORNL; May, Andrew F [ORNL; Williams, Travis J [ORNL; Poudel, Lekhanath N [ORNL; Calder, Stuart A [ORNL; Fishman, Randy Scott [ORNL; Stone, Matthew B [ORNL; Aczel, Adam A [ORNL; Cao, Huibo [ORNL; Lumsden, Mark D [ORNL; Christianson, Andrew D [ORNL

    2015-01-01

    We report elastic and inelastic neutron scattering measurements of the high-TC ferromagnet Mn(1+delta)Sb. Measurements were performed on a large, TC = 434 K, single crystal with interstitial Mn content of delta=0.13. The neutron diffraction results reveal that the interstitial Mn has a magnetic moment, and that it is aligned antiparallel to the main Mn moment. We perform density functional theory calculations including the interstitial Mn, and find the interstitial to be magnetic in agreement with the diffraction data. The inelastic neutron scattering measurements reveal two features in the magnetic dynamics: i) a spin-wave-like dispersion emanating from ferromagnetic Bragg positions (H K 2n), and ii) a broad, non-dispersive signal centered at forbidden Bragg positions (H K 2n+1). The inelastic spectrum cannot be modeled by simple linear spin-wave theory calculations, and appears to be significantly altered by the presence of the interstitial Mn ions. The results show that the influence of the int

  1. Activity of the kinesin spindle protein inhibitor ispinesib (SB-715992) in models of breast cancer

    SciTech Connect (OSTI)

    Purcell, James W; Davis, Jefferson; Reddy, Mamatha; Martin, Shamra; Samayoa, Kimberly; Vo, Hung; Thomsen, Karen; Bean, Peter; Kuo, Wen Lin; Ziyad, Safiyyah; Billig, Jessica; Feiler, Heidi S; Gray, Joe W; Wood, Kenneth W; Cases, Sylvaine

    2009-06-10

    Ispinesib (SB-715992) is a potent inhibitor of kinesin spindle protein (KSP), a kinesin motor protein essential for the formation of a bipolar mitotic spindle and cell cycle progression through mitosis. Clinical studies of ispinesib have demonstrated a 9% response rate in patients with locally advanced or metastatic breast cancer, and a favorable safety profile without significant neurotoxicities, gastrointestinal toxicities or hair loss. To better understand the potential of ispinesib in the treatment of breast cancer we explored the activity of ispinesib alone and in combination several therapies approved for the treatment of breast cancer. We measured the ispinesib sensitivity and pharmacodynamic response of breast cancer cell lines representative of various subtypes in vitro and as xenografts in vivo, and tested the ability of ispinesib to enhance the anti-tumor activity of approved therapies. In vitro, ispinesib displayed broad anti-proliferative activity against a panel of 53 breast cell-lines. In vivo, ispinesib produced regressions in each of five breast cancer models, and tumor free survivors in three of these models. The effects of ispinesib treatment on pharmacodynamic markers of mitosis and apoptosis were examined in vitro and in vivo, revealing a greater increase in both mitotic and apoptotic markers in the MDA-MB-468 model than in the less sensitive BT-474 model. In vivo, ispinesib enhanced the anti-tumor activity of trastuzumab, lapatinib, doxorubicin, and capecitabine, and exhibited activity comparable to paclitaxel and ixabepilone. These findings support further clinical exploration of KSP inhibitors for the treatment of breast cancer.

  2. The young nuclear stellar disc in the SB0 galaxy NGC 1023

    E-Print Network [OSTI]

    Corsini, E M; Pastorello, N; Bontà, E Dalla; Pizzella, A; Portaluri, E

    2015-01-01

    Small kinematically-decoupled stellar discs with scalelengths of a few tens of parsec are known to reside in the centre of galaxies. Different mechanisms have been proposed to explain how they form, including gas dissipation and merging of globular clusters. Using archival Hubble Space Telescope imaging and ground-based integral-field spectroscopy, we investigated the structure and stellar populations of the nuclear stellar disc hosted in the interacting SB0 galaxy NGC 1023. The stars of the nuclear disc are remarkably younger and more metal rich with respect to the host bulge. These findings support a scenario in which the nuclear disc is the end result of star formation in metal enriched gas piled up in the galaxy centre. The gas can be of either internal or external origin, i.e. from either the main disc of NGC 1023 or the nearby satellite galaxy NGC 1023A. The dissipationless formation of the nuclear disc from already formed stars, through the migration and accretion of star clusters into the galactic cen...

  3. Active optical zoom system

    DOE Patents [OSTI]

    Wick, David V.

    2005-12-20

    An active optical zoom system changes the magnification (or effective focal length) of an optical imaging system by utilizing two or more active optics in a conventional optical system. The system can create relatively large changes in system magnification with very small changes in the focal lengths of individual active elements by leveraging the optical power of the conventional optical elements (e.g., passive lenses and mirrors) surrounding the active optics. The active optics serve primarily as variable focal-length lenses or mirrors, although adding other aberrations enables increased utility. The active optics can either be LC SLMs, used in a transmissive optical zoom system, or DMs, used in a reflective optical zoom system. By appropriately designing the optical system, the variable focal-length lenses or mirrors can provide the flexibility necessary to change the overall system focal length (i.e., effective focal length), and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses. The active optics can provide additional flexibility by allowing magnification to occur anywhere within the FOV of the system, not just on-axis as in a conventional system.

  4. SLUDGE BATCH 5 ACCEPTANCE EVALUATION RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB5 QUALIFICATION SAMPLE PREPARED AT SRNL

    SciTech Connect (OSTI)

    Bannochie, C; Ned Bibler, N; David Diprete, D

    2008-07-28

    Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch Five (SB5) for processing in the Defense Waste Processing Facility (DWPF). Part of this SB5 material is currently in Tank 51 being washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40 to complete the formation of SB5. The sludge slurry in Tank 40 has already been qualified for DWPF and is currently being processed as SB4. The radionuclide concentrations were measured or estimated in the Tank 51 SB5 Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from the three liter sample of Tank 51 sludge slurry taken on March 21, 2008. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. Under direction of the Liquid Waste Organization it was then modified by five washes, six decants, an addition of Pu/Be from Canyon Tank 16.4, and an addition of NaNO2. This final slurry now has a composition expected to be similar to that of the slurry in Tank 51 after final preparations have been made for transfer of that slurry to Ta Determining the radionuclide concentrations in this Tank 51 SB5 Qualification Sample is part of the work requested in Technical Task Request (TTR) No. HLW-DWPF-TTR-2008-0010. The work with this qualification sample is covered by a Task Technical and Quality Assurance Plan and an Analytical Study Plan. The radionuclides included in this report are needed for the DWPF Radiological Program Evaluation, the DWPF Waste Acceptance Criteria (TSR/WAC) Evaluation, and the DWPF Solid Waste Characterization Program (TTR Task 2). Radionuclides required to meet the Waste Acceptance Product Specifications (TTR Task 5) will be measured at a later date after the slurry from Tank 51 has been transferred to Tank 40. Then a sample of the as-processed SB5 will be taken and transferred to SRNL for measurement of these radionuclides. Data presented in this report represents the measured or estimated radionuclide concentrations obtained from several standard and special analytical methods performed by Analytical Development (AD) personnel within SRNL. The method for I-129 measurement in sludge is described in detail. Most of these methods were performed on solutions resulting from the dissolutions of the slurry samples. Concentrations are given for twenty-nine radionuclides along with total alpha and beta activity. Values for total gamma and total gamma plus beta activities are also calculated. Results also indicate that 98% of the Tc-99 and 92% of the I-129 that could have been in this sludge batch have been removed by chemical processing steps in the SRS Canyons or Tank Farm.

  5. SLUDGE BATCH 6 ACCEPTANCE EVALUATION: RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB6 QUALIFICATION SAMPLE PREPARED AT SRNL

    SciTech Connect (OSTI)

    Bannochie, C.; Bibler, N.; Diprete, D.

    2010-05-21

    Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch Six (SB6) for processing in the Defense Waste Processing Facility (DWPF). The SB6 material is currently in Tank 51 being washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40. The sludge slurry in Tank 40 has already been qualified for DWPF and is currently being processed as SB5. The radionuclide concentrations were measured or estimated in the Tank 51 SB6 Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from the three liter sample of Tank 51 sludge slurry (HTF-51-09-110) taken on October 8, 2009. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. Under the direction of the Liquid Waste Organization it was then modified by eight washes, nine decants, an addition of Pu from Canyon Tank 16.3, and an addition of NaNO{sub 2}. This final slurry now has a composition expected to be similar to that of the slurry in Tank 51 after final preparations have been made for transfer of that slurry to Tank 40. Determining the radionuclide concentrations in this Tank 51 SB6 Qualification Sample is part of the work requested in Technical Task Request (TTR) No. HLW-DWPF-TTR-2009-0014. The work with this qualification sample is covered by a Task Technical and Quality Assurance Plan and an Analytical Study Plan. The radionuclides included in this report are needed for the DWPF Radiological Program Evaluation, the DWPF Waste Acceptance Criteria (TSR/WAC) Evaluation, and the DWPF Solid Waste Characterization Program (TTR Task I.2). Radionuclides required to meet the Waste Acceptance Product Specifications (TTR Task II.2.) will be measured at a later date after the slurry from Tank 51 has been transferred to Tank 40. Then a sample of the as-processed SB6 will be taken and transferred to SRNL for measurement of these radionuclides. The results presented in this report are those necessary for DWPF to assess if the Tank 51 SB6 sample prepared at SRNL meets the requirements for the DWPF Radiological Program Evaluation, the DWPF Waste Acceptance Criteria evaluation, and the DWPF Solid Waste Characterization Program. The sample is the same as that on which the chemical composition was reported. Concentrations are given for thirty-four radionuclides along with total alpha and beta activity. Values for total gamma and total gamma plus beta activities are also calculated. Results also indicate that 99% of the Tc-99 and at least 90% of the I-129 that could have been in this sludge batch have been removed by chemical processing steps in the SRS Canyons or Tank Farm.

  6. LABORATORY VII: WAVE OPTICS

    E-Print Network [OSTI]

    Minnesota, University of

    LABORATORY VII: WAVE OPTICS Lab VII - 1 In this lab, you will solve problems in ways that take-like behavior. These conditions may be less familiar to you than the conditions for which geometrical optics

  7. High bandwidth optical mount

    DOE Patents [OSTI]

    Bender, D.A.; Kuklo, T.

    1994-11-08

    An optical mount, which directs a laser beam to a point by controlling the position of a light-transmitting optic, is stiffened so that a lowest resonant frequency of the mount is approximately one kilohertz. The optical mount, which is cylindrically-shaped, positions the optic by individually moving a plurality of carriages which are positioned longitudinally within a sidewall of the mount. The optical mount is stiffened by allowing each carriage, which is attached to the optic, to move only in a direction which is substantially parallel to a center axis of the optic. The carriage is limited to an axial movement by flexures or linear bearings which connect the carriage to the mount. The carriage is moved by a piezoelectric transducer. By limiting the carriage to axial movement, the optic can be kinematically clamped to a carriage. 5 figs.

  8. Space Science: Atmospheres Evolution of planets

    E-Print Network [OSTI]

    Johnson, Robert E.

    ;Atmospheres / Evolution Heat Sources Compressional Energy Trapped Radioactive Material Tidal InteractionsSpace Science: Atmospheres Part- 7a Evolution of planets Out-Gassing/ Volcanoes Evolution Initial Species Solar abundance Solar wind composition? Carbonaceous chondrites? Variables Early sun

  9. ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2012)

    E-Print Network [OSTI]

    Gerber, Edwin

    2012-01-01

    ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2012) Published online in Wiley Online Library using National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP) concentrations and sea- surface temperatures (SSTs). These integrations enable the relative role of ozone

  10. Equilibration of an atmosphere by geostrophic turbulence

    E-Print Network [OSTI]

    Jansen, Malte F. (Malte Friedrich)

    2013-01-01

    A major question for climate studies is to quantify the role of turbulent eddy fluxes in maintaining the observed atmospheric mean state. It has been argued that eddy fluxes keep the mid-latitude atmosphere in a state that ...

  11. Land and Atmospheric Science GRAD STUDENT HANDBOOK

    E-Print Network [OSTI]

    Minnesota, University of

    Land and Atmospheric Science GRAD STUDENT HANDBOOK 20142015 WELCOME Welcome to the Graduate Program in Land and Atmospheric Science at the University of Minnesota. It is a sciencebased interdisciplinary program focused on the fundamentals of Earth system processes related

  12. Atmospheric Chemistry and Air Pollution

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gaffney, Jeffrey S.; Marley, Nancy A.

    2003-01-01

    Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry in industrial areas. Regional air pollution issues such as acid rain, long-range transport of aerosols and visibility loss, and the connections of aerosols to ozonemore »and peroxyacetyl nitrate chemistry are examined. Finally, the potential impacts of air pollutants on the global-scale radiative balances of gases and aerosols are discussed briefly.« less

  13. Reflective optical imaging system

    DOE Patents [OSTI]

    Shafer, David R. (Fairfield, CT)

    2000-01-01

    An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four reflective elements for projecting a mask image onto a substrate. The four optical elements are characterized in order from object to image as convex, concave, convex and concave mirrors. The optical system is particularly suited for step and scan lithography methods. The invention increases the slit dimensions associated with ringfield scanning optics, improves wafer throughput and allows higher semiconductor device density.

  14. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, R.; Kotter, D.

    1994-04-26

    An optical voltage reference for providing an alternative to a battery source is described. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function. 2 figures.

  15. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, Richard (Ammon, ID); Kotter, Dale (Bingham County, ID)

    1994-01-01

    An optical voltage reference for providing an alternative to a battery source. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function.

  16. Radar range measurements in the atmosphere.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2013-02-01

    The earth's atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.

  17. Earth and Atmospheric Sciences | More Science | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Earth and Atmospheric Sciences Nuclear Forensics Climate & Environment Sensors and Measurements Chemical & Engineering Materials Computational Earth Science Systems Modeling...

  18. Atmospheric-pressure plasma jet

    DOE Patents [OSTI]

    Selwyn, Gary S. (Los Alamos, NM)

    1999-01-01

    Atmospheric-pressure plasma jet. A .gamma.-mode, resonant-cavity plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two concentric cylindrical electrodes are employed to generate a plasma in the annular region therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly shaping the rf-powered electrode. Because of the atmospheric pressure operation, no ions survive for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike low-pressure plasma sources and conventional plasma processing methods.

  19. A Recognized Leader in Marine & Atmospheric

    E-Print Network [OSTI]

    Miami, University of

    D/Masters Applied Marine Physics Marine & Atmospheric Chemistry Marine Affairs & Policy (Masters Only) MarineA Recognized Leader in Marine & Atmospheric Studies Our graduate program has over 250 students University of MiaMi rosenstiel school of Marine & atMospheric science #12;Miami Ranks #5: fDi Magazine's Top

  20. Atmospheric evolution on Venus Bruce Fegley, Jr.

    E-Print Network [OSTI]

    1 Atmospheric evolution on Venus Bruce Fegley, Jr. Planetary Chemistry Laboratory Department by Hunten et al. (1983), of Magellan results by Bougher et al. (1997), and atmospheric chemistry on Venus and Ancient Environments Edited by Vivien Gornitz January 2004 #12;2 ATMOSPHERIC EVOLUTION ON VENUS Overview

  1. Atmospheric Lifetime of Fossil Fuel Carbon Dioxide

    E-Print Network [OSTI]

    Atmospheric Lifetime of Fossil Fuel Carbon Dioxide David Archer,1 Michael Eby,2 Victor Brovkin,3 released from combustion of fossil fuels equilibrates among the various carbon reservoirs of the atmosphere literature on the atmospheric lifetime of fossil fuel CO2 and its impact on climate, and we present initial

  2. Proof of the Atmospheric Greenhouse Effect

    E-Print Network [OSTI]

    Smith, Arthur P

    2008-01-01

    A recently advanced argument against the atmospheric greenhouse effect is refuted. A planet without an infrared absorbing atmosphere is mathematically constrained to have an average temperature less than or equal to the effective radiating temperature. Observed parameters for Earth prove that without infrared absorption by the atmosphere, the average temperature of Earth's surface would be at least 33 K lower than what is observed.

  3. University of Central Florida College of Optics & Photonics Optics

    E-Print Network [OSTI]

    Van Stryland, Eric

    University of Central Florida College of Optics & Photonics Optics Spring 2010 OSE-6432: Principles of guided wave optics; electro -optics, acousto-optics and optoelectronics. Location: CREOL-A-214 or by Appointment Reference Materials: 1. Class Notes. 2. "Fundamentals of Optical Waveguides", K. Okamoto, Academic

  4. Stable microwave coaxial cavity plasma system at atmospheric pressure

    SciTech Connect (OSTI)

    Song, H. [Department of Electrical and Computer Engineering, University of Colorado, Colorado Springs, Colorado 80918 (United States); Hong, J. M.; Lee, K. H. [Plasma Systems and Materials (PSM) Inc., Sungnam-Si, Gyonggi-Do 190-1 (Korea, Republic of); Choi, J. J. [Department of Radio Science and Engineering, Kwangwoon University, Nowon-Gu, Seoul 447-1 (Korea, Republic of)

    2008-05-15

    We present a systematic study of the development of a novel atmospheric microwave plasma system for material processing in the pressure range up to 760 torr and the microwave input power up to 6 kW. Atmospheric microwave plasma was reliably produced and sustained by using a cylindrical resonator with the TM{sub 011} cavity mode. The applicator and the microwave cavity, which is a cylindrical resonator, are carefully designed and optimized with the time dependent finite element Maxwell equation solver. The azimuthal apertures are placed at the maximum magnetic field positions between the cavity and the applicator to maximize the coupling efficiency into the microwave plasma at a resonant frequency of 2.45 GHz. The system consists of a magnetron power supply, a circulator, a directional coupler, a three-stub tuner, a dummy load, a coaxial cavity, and a central cavity. Design and construction of the resonant structures and diagnostics of atmospheric plasma using optical experiments are discussed in various ranges of pressure and microwave input power for different types of gases.

  5. Atmospheric characterization of the hot Jupiter Kepler-13Ab

    SciTech Connect (OSTI)

    Shporer, Avi; O'Rourke, Joseph G.; Knutson, Heather A.; Szabó, Gyula M.; Zhao, Ming; Burrows, Adam; Fortney, Jonathan; Agol, Eric; Cowan, Nicolas B.; Desert, Jean-Michel; Howard, Andrew W.; Isaacson, Howard; Lewis, Nikole K.; Showman, Adam P.; Todorov, Kamen O.

    2014-06-10

    Kepler-13Ab (= KOI-13.01) is a unique transiting hot Jupiter. It is one of very few known short-period planets orbiting a hot A-type star, making it one of the hottest planets currently known. The availability of Kepler data allows us to measure the planet's occultation (secondary eclipse) and phase curve in the optical, which we combine with occultations observed by warm Spitzer at 4.5 ?m and 3.6 ?m and a ground-based occultation observation in the K{sub s} band (2.1 ?m). We derive a day-side hemisphere temperature of 2750 ± 160 K as the effective temperature of a black body showing the same occultation depths. Comparing the occultation depths with one-dimensional planetary atmosphere models suggests the presence of an atmospheric temperature inversion. Our analysis shows evidence for a relatively high geometric albedo, A {sub g} = 0.33{sub ?0.06}{sup +0.04}. While measured with a simplistic method, a high A {sub g} is supported also by the fact that the one-dimensional atmosphere models underestimate the occultation depth in the optical. We use stellar spectra to determine the dilution, in the four wide bands where occultation was measured, due to the visual stellar binary companion 1.''15 ± 0.''05 away. The revised stellar parameters measured using these spectra are combined with other measurements, leading to revised planetary mass and radius estimates of M{sub p} = 4.94-8.09 M {sub J} and R{sub p} = 1.406 ± 0.038 R {sub J}. Finally, we measure a Kepler midoccultation time that is 34.0 ± 6.9 s earlier than expected based on the midtransit time and the delay due to light-travel time and discuss possible scenarios.

  6. A TRANSMISSION SPECTRUM OF TITAN'S NORTH POLAR ATMOSPHERE FROM A SPECULAR REFLECTION OF THE SUN

    SciTech Connect (OSTI)

    Barnes, Jason W.; Clark, Roger N.; Sotin, Christophe; Buratti, Bonnie J.; Ádámkovics, Máté; Appéré, Thomas; Rodriguez, Sebastien; Brown, Robert H.; Baines, Kevin H.; Le Mouélic, Stéphane; Nicholson, Philip D.

    2013-11-10

    Cassini/VIMS T85 observations of a solar specular reflection off of Kivu Lacus (87.°4N 241.°1E) provide an empirical transmission spectrum of Titan's atmosphere. Because this observation was acquired from short range (33,000 km), its intensity makes it visible within the 2.0, 2.7, and 2.8 ?m atmospheric windows in addition to the 5 ?m window where all previous specular reflections have been seen. The resulting measurement of the total one-way normal atmospheric optical depth (corresponding to haze scattering plus haze and gas absorption) provides strong empirical constraints on radiative transfer models. Using those models, we find that the total haze column abundance in our observation is 20% higher than the Huygens equatorial value. Ours is the first measurement in the 2-5 ?m wavelength range that probes all the way to the surface in Titan's arctic, where the vast majority of surface liquids are located. The specular technique complements other probes of atmospheric properties such as solar occultations and the direct measurements from Huygens. In breaking the degeneracy between surface and atmospheric absorptions, our measured optical depths will help to drive future calculations of deconvolved surface albedo spectra.

  7. Atmospheric composition change - global and regional air quality

    E-Print Network [OSTI]

    2009-01-01

    in urban air. Atmospheric Chemistry and Physics 5, 2881–deep convective system. Atmospheric Chemistry and Physics 4,processes in atmospheric chemistry. Chemical Society Review

  8. Coupling of nitrous oxide and methane by global atmospheric chemistry

    E-Print Network [OSTI]

    Prather, MJ; Hsu, J

    2010-01-01

    supported by NSF’s Atmospheric Chemistry program (grant ATM-Methane by Global Atmospheric Chemistry Michael J. Prathergas, through atmospheric chemistry that en- hances the

  9. Formation mechanisms and quantification of organic nitrates in atmospheric aerosol

    E-Print Network [OSTI]

    Rollins, Andrew Waite

    2010-01-01

    and J. Viidanoja, Atmospheric chemistry of c 3 -c 6organic nitrates, Atmospheric Chemistry and Physics, 9 (4),organic aerosol yields, Atmospheric Chemistry and Physics

  10. 1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists

    SciTech Connect (OSTI)

    Paul H. Wine

    1998-11-23

    DOE's Atmospheric Chemistry Program is providing partial funding for the Atmospheric Chemistry Colloquium for Emerging Senior Scientists (ACCESS) and FY 1997 Gordon Research Conference in Atmospheric Chemistry

  11. Improved determination of the atmospheric parameters of the pulsating sdB star Feige 48

    SciTech Connect (OSTI)

    Latour, M.; Fontaine, G.; Brassard, P.; Green, E. M.; Chayer, P.

    2014-06-10

    As part of a multifaceted effort to better exploit the asteroseismological potential of the pulsating sdB star Feige 48, we present an improved spectroscopic analysis of that star based on new grids of NLTE, fully line-blanketed model atmospheres. To that end, we gathered four high signal-to-noise ratio time-averaged optical spectra of varying spectral resolutions from 1.0 Å to 8.7 Å, and we made use of the results of four independent studies to fix the abundances of the most important metals in the atmosphere of Feige 48. The mean atmospheric parameters we obtained from our four spectra of Feige 48 are: T {sub eff} = 29,850 ± 60 K, log g = 5.46 ± 0.01, and log N(He)/N(H) = –2.88 ± 0.02. We also modeled, for the first time, the He II line at 1640 Å from the STIS archive spectrum of the star, and with this line we found an effective temperature and a surface gravity that match well with the values obtained with the optical data. With some fine tuning of the abundances of the metals visible in the optical domain, we were able to achieve a very good agreement between our best available spectrum and our best-fitting synthetic one. Our derived atmospheric parameters for Feige 48 are in rather good agreement with previous estimates based on less sophisticated models. This underlines the relatively small effects of the NLTE approach combined with line blanketing in the atmosphere of this particular star, implying that the current estimates of the atmospheric parameters of Feige 48 are reliable and secure.

  12. Quantum Optics (Nir Davidson -

    E-Print Network [OSTI]

    Ribak, Erez

    Digital Holography" Georg Witt, and A. Cohen*, University of Stockholm, Sweden and *Dept. of Atmospheric (Dony Meshulach - Applied Materials, Israel) Naor Wainer, Philips Medical Systems Technologies

  13. High quality HfO{sub 2}/p-GaSb(001) metal-oxide-semiconductor capacitors with 0.8?nm equivalent oxide thickness

    SciTech Connect (OSTI)

    Barth, Michael; Datta, Suman; Bruce Rayner, G.; McDonnell, Stephen; Wallace, Robert M.; Bennett, Brian R.; Engel-Herbert, Roman

    2014-12-01

    We investigate in-situ cleaning of GaSb surfaces and its effect on the electrical performance of p-type GaSb metal-oxide-semiconductor capacitor (MOSCAP) using a remote hydrogen plasma. Ultrathin HfO{sub 2} films grown by atomic layer deposition were used as a high permittivity gate dielectric. Compared to conventional ex-situ chemical cleaning methods, the in-situ GaSb surface treatment resulted in a drastic improvement in the impedance characteristics of the MOSCAPs, directly evidencing a much lower interface trap density and enhanced Fermi level movement efficiency. We demonstrate that by using a combination of ex-situ and in-situ surface cleaning steps, aggressively scaled HfO{sub 2}/p-GaSb MOSCAP structures with a low equivalent oxide thickness of 0.8?nm and efficient gate modulation of the surface potential are achieved, allowing to push the Fermi level far away from the valence band edge high up into the band gap of GaSb.

  14. Interfacial structure, bonding and composition of InAs and GaSb thin films determined using coherent Bragg rod analysis.

    SciTech Connect (OSTI)

    Cionca, C.; Walko, D. A.; Yacoby, Y.; Dorin, C.; Millunchick, J. M.; Clarke, R.; X-Ray Science Division; Univ. of Michigan; Hebrew Univ.

    2007-01-01

    We have used Bragg rod x-ray diffraction combined with a direct method of phase retrieval to extract atomic resolution electron-density maps of a complementary series of heteroepitaxial III-V semiconductor samples. From the three-dimensional electron-density maps we derive the monolayer spacings, the chemical compositions, and the characteristics of the bonding for all atomic planes in the film and across the film-substrate interface. InAs films grown on GaSb(001) under two different As conditions (using dimer or tetramer forms) both showed conformal roughness and mixed GaAs/InSb interfacial bonding character. The As tetramer conditions favored InSb bonding at the interface while, in the case of the dimer, the percentages corresponding to GaAs and InSb bonding were equal within the experimental error. The GaSb film grown on InAs(001) displayed significant In and As interdiffusion and had a relatively large fraction of GaAs-like bonds at the interface.

  15. INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF OPTICS A: PURE AND APPLIED OPTICS Nanostructures + Light = `New Optics'

    E-Print Network [OSTI]

    Zheludev, Nikolay

    INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF OPTICS A: PURE AND APPLIED OPTICS EDITORIAL Nanostructures + Light = `New Optics' Guest Editors Nikolay Zheludev University of Southampton, UK Vladimir optics and classical electrodynamics became fashionable again. Fields that several generations

  16. Fiber optic vibration sensor

    DOE Patents [OSTI]

    Dooley, Joseph B. (Harriman, TN); Muhs, Jeffrey D. (Lenoir City, TN); Tobin, Kenneth W. (Harriman, TN)

    1995-01-01

    A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity.

  17. Fiber optic vibration sensor

    DOE Patents [OSTI]

    Dooley, J.B.; Muhs, J.D.; Tobin, K.W.

    1995-01-10

    A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity. 2 figures.

  18. Omnidirectional fiber optic tiltmeter

    DOE Patents [OSTI]

    Benjamin, B.C.; Miller, H.M.

    1983-06-30

    A tiltmeter is provided which is useful in detecting very small movements such as earth tides. The device comprises a single optical fiber, and an associated weight affixed thereto, suspended from a support to form a pendulum. A light source, e.g., a light emitting diode, mounted on the support transmits light through the optical fiber to a group of further optical fibers located adjacent to but spaced from the free end of the single optical fiber so that displacement of the single optical fiber with respect to the group will result in a change in the amount of light received by the individual optical fibers of the group. Photodetectors individually connectd to the fibers produce corresponding electrical outputs which are differentially compared and processed to produce a resultant continuous analog output representative of the amount and direction of displacement of the single optical fiber.

  19. Pulsed atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Design and Engineering of most components in the Pulsed Atmospheric Fluidized Bed System was completed prior to September 1992. The components remaining to be designed at that time were: Aerovalves for the Pulse Combustor; Gas and coal injectors for the Pulse Combustor; Lines for PC tailpipes; Air plenum and inlet silencer; Refractory lined hot gas duct connecting outlet hot cyclone to boiler; Structure and platforms, and ladders around PAFBC vessel access and major equipment. Design work is currently in progress on all of the above components. Items 1, 2, 3 and 4 are 50% completed, and items 5 6 are 75% complete.

  20. Natalie Marie Mahowald Department of Earth and Atmospheric Sciences

    E-Print Network [OSTI]

    Mahowald, Natalie

    in the Community Atmosphere Model: development of framework and impact on radiative forcing, Atmospheric Chemistry, Atmospheric Chemistry and 1 1 Natalie Marie Mahowald Department of Earth and Atmospheric Sciences Professor Director

  1. Anisotropic magnetization and transport properties of RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm)

    SciTech Connect (OSTI)

    Myers, Kenneth D.

    1999-11-08

    This study of the RAgSb{sub 2} series of compounds arose as part of an investigation of rare earth intermetallic compounds containing antimony with the rare earth in a position with tetragonal point symmetry. Materials with the rare earth in a position with tetragonal point symmetry frequently manifest strong anisotropies and rich complexity in the magnetic properties, and yet are simple enough to analyze. Antimony containing intermetallic compounds commonly possess low carrier densities and have only recently been the subject of study. Large single grain crystals were grown of the RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm) series of compounds out of a high temperature solution. This method of crystal growth, commonly known as flux growth is a versatile method which takes advantage of the decreasing solubility of the target compound with decreasing temperature. Overall, the results of the crystal growth were impressive with the synthesis of single crystals of LaAgSb{sub 2} approaching one gram. However, the sample yield diminishes as the rare earth elements become smaller and heavier. Consequently, no crystals could be grown with R=Yb or Lu. Furthermore, EuAgSb{sub 2} could not be synthesized, likely due to the divalency of the Eu ion. For most of the RAgSb{sub 2} compounds, strong magnetic anisotropies are created by the crystal electric field splitting of the Hund's rule ground state. This splitting confines the local moments to lie in the basal plane (easy plane) for the majority of the members of the series. Exceptions to this include ErAgSb{sub 2} and TmAgSb{sub 2}, which have moments along the c-axis (easy axis) and CeAgSb{sub 2}, which at intermediate temperatures has an easy plane, but exchange coupling at low temperatures is anisotropic with an easy axis. Additional anisotropy is also observed within the basal plane of DyAgSb{sub 2}, where the moments are restricted to align along one of the {l_angle}110{r_angle} axes. Most of the RAgSb{sub 2} compounds containing magnetic rare earths, antiferromagnetically ordered at low temperatures. The ordering temperatures of these compounds are approximately proportional to the de Gennes factor, which suggests that the RKKY interaction is the dominant exchange interaction between local moments. Although metamagnetic transitions were observed in many members of the series, the series of sharp step-like transitions in DyAgSb{sub 2} are impressive. In this compound, up to 11 different magnetic states are stable depending on the magnitude and direction of the applied field. The saturated magnetization of these states and the critical fields needed to induce a phase transition vary with the direction of the applied field. Through detailed study of the angular dependence of the magnetization and critical fields, the net distribution of magnetic moments was determined for most, of the metamagnetic states. In DyAgSb{sub 2}, the crystal electric field (CEF) splitting of the Hund's rule ground state creates a strong anisotropy where the local Dy{sup 3+} magnetic moments are constrained to one of the equivalent {l_angle}110{r_angle} directions within the basal plane. The four position clock model was introduced to account for this rich metamagnetic system. Within this model, the magnetic moments are constrained to one of four equivalent orientations within the basal plane and interactions are calculated for up third nearest neighbors. The theoretical phase diagram, generated from the coupling constants is in excellent agreement with the experimental phase diagram. Further investigation of this compound using magnetic X-ray or neutron diffraction would be extremely useful to verify the net distributions of moments and determine the wave vectors of each of the ordered states.

  2. Demonstrating 1 nm-oxide-equivalent-thickness HfO{sub 2}/InSb structure with unpinning Fermi level and low gate leakage current density

    SciTech Connect (OSTI)

    Trinh, Hai-Dang [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China) [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Lin, Yueh-Chin; Nguyen, Hong-Quan; Luc, Quang-Ho [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China)] [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Nguyen, Minh-Thuy; Duong, Quoc-Van; Nguyen, Manh-Nghia [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam)] [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Wang, Shin-Yuan [Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China)] [Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China); Yi Chang, Edward [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China) [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China)

    2013-09-30

    In this work, the band alignment, interface, and electrical characteristics of HfO{sub 2}/InSb metal-oxide-semiconductor structure have been investigated. By using x-ray photoelectron spectroscopy analysis, the conduction band offset of 1.78 ± 0.1 eV and valence band offset of 3.35 ± 0.1 eV have been extracted. The transmission electron microscopy analysis has shown that HfO{sub 2} layer would be a good diffusion barrier for InSb. As a result, 1 nm equivalent-oxide-thickness in the 4 nm HfO{sub 2}/InSb structure has been demonstrated with unpinning Fermi level and low leakage current of 10{sup ?4} A/cm{sup ?2}. The D{sub it} value of smaller than 10{sup 12} eV{sup ?1}cm{sup ?2} has been obtained using conduction method.

  3. Growth and transport properties of epitaxial lattice matched half Heusler CoTiSb/InAlAs/InP(001) heterostructures

    SciTech Connect (OSTI)

    Kawasaki, Jason K.; Johansson, Linda I. M.; Schultz, Brian D.; Palmstrøm, Chris J.

    2014-01-13

    We demonstrate the integration of the lattice matched single crystal epitaxial Half Heusler compound CoTiSb with In{sub 0.52}Al{sub 0.48}As/InP(001) heterostructures using molecular beam epitaxy. CoTiSb belongs to the subset of Half Heusler compounds that is expected to be semiconducting, despite being composed entirely of metallic constituents. The lattice matching and epitaxial alignment of the CoTiSb films were confirmed by reflection high energy electron diffraction and X-ray diffraction. Temperature dependent transport measurements indicate semiconducting-like behavior, with a room temperature Hall mobility of 530 cm{sup 2}/Vs and background Hall carrier density of 9.0?×?10{sup 17}?cm{sup ?3}, which is comparable to n-Si with similar carrier density. Below 100?K, the films show a large negative magnetoresistance, and possible origins of this negative magnetoresistance are discussed.

  4. Regional Ecosystem-Atmosphere CO2 Exchange Via Atmospheric Budgets

    SciTech Connect (OSTI)

    Davis, K.J.; Richardson, S.J.; Miles, N.L.

    2007-03-07

    Inversions of atmospheric CO2 mixing ratio measurements to determine CO2 sources and sinks are typically limited to coarse spatial and temporal resolution. This limits our ability to evaluate efforts to upscale chamber- and stand-level CO2 flux measurements to regional scales, where coherent climate and ecosystem mechanisms govern the carbon cycle. As a step towards the goal of implementing atmospheric budget or inversion methodology on a regional scale, a network of five relatively inexpensive CO2 mixing ratio measurement systems was deployed on towers in northern Wisconsin. Four systems were distributed on a circle of roughly 150-km radius, surrounding one centrally located system at the WLEF tower near Park Falls, WI. All measurements were taken at a height of 76 m AGL. The systems used single-cell infrared CO2 analyzers (Licor, model LI-820) rather than the siginificantly more costly two-cell models, and were calibrated every two hours using four samples known to within ± 0.2 ppm CO2. Tests prior to deployment in which the systems sampled the same air indicate the precision of the systems to be better than ± 0.3 ppm and the accuracy, based on the difference between the daily mean of one system and a co-located NOAA-ESRL system, is consistently better than ± 0.3 ppm. We demonstrate the utility of the network in two ways. We interpret regional CO2 differences using a Lagrangian parcel approach. The difference in the CO2 mixing ratios across the network is at least 2?3 ppm, which is large compared to the accuracy and precision of the systems. Fluxes estimated assuming Lagrangian parcel transport are of the same sign and magnitude as eddy-covariance flux measurements at the centrally-located WLEF tower. These results indicate that the network will be useful in a full inversion model. Second, we present a case study involving a frontal passage through the region. The progression of a front across the network is evident; changes as large as four ppm in one minute are captured. Influence functions, derived using a Lagrangian Particle Dispersion model driven by the CSU Regional Atmospheric Modeling System and nudged to NCEP reanalysis meteorological fields, are used to determine source regions for the towers. The influence functions are combined with satellite vegetation observations to interpret the observed trends in CO2 concentration. Full inversions will combine these elements in a more formal analytic framework.

  5. 1EV GaN[subscript x]As[subscript 1-x-y]Sb[subscript y] material for lattice-matched III-V solar cell implementation on GaAs and Ge

    E-Print Network [OSTI]

    Yoon, Soon Fatt

    The effect of different arsenic species (As[subscript 2] or As[subscript 4]) on the quality of molecular beam epitaxy (MBE) grown GaNAsSb materials (samples A and B) and GaAs/ GaNAsSb/GaAs p+n-n+ devices (samples C and D) ...

  6. No. 16 ISSN 10278389 March 2012 The Southern African Large Telescope (Courtesy: S.B. Potter)

    E-Print Network [OSTI]

    Jarrett, Thomas H.

    P. Martinez South Africa Editor: wgssa@saao.ac.za P. Spargo South Africa P. Okeke Nigeria misunn-East and Africa. In partic- ular, the completion of HESS (the High Energy Stereoscopic System, in Namibia-class observational capability from ultra-high energy gamma-rays, through optical/near-IR to radio wave- lengths

  7. Compound semiconductor optical waveguide switch

    DOE Patents [OSTI]

    Spahn, Olga B.; Sullivan, Charles T.; Garcia, Ernest J.

    2003-06-10

    An optical waveguide switch is disclosed which is formed from III-V compound semiconductors and which has a moveable optical waveguide with a cantilevered portion that can be bent laterally by an integral electrostatic actuator to route an optical signal (i.e. light) between the moveable optical waveguide and one of a plurality of fixed optical waveguides. A plurality of optical waveguide switches can be formed on a common substrate and interconnected to form an optical switching network.

  8. Transpiration purged optical probe

    DOE Patents [OSTI]

    2004-01-06

    An optical apparatus for clearly viewing the interior of a containment vessel by applying a transpiration fluid to a volume directly in front of the external surface of the optical element of the optical apparatus. The fluid is provided by an external source and transported by means of an annular tube to a capped end region where the inner tube is perforated. The perforation allows the fluid to stream axially towards the center of the inner tube and then axially away from an optical element which is positioned in the inner tube just prior to the porous sleeve. This arrangement draws any contaminants away from the optical element keeping it free of contaminants. In one of several embodiments, the optical element can be a lens, a viewing port or a laser, and the external source can provide a transpiration fluid having either steady properties or time varying properties.

  9. Optical atomic magnetometer

    DOE Patents [OSTI]

    Budker, Dmitry; Higbie, James; Corsini, Eric P.

    2013-11-19

    An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

  10. 27 Jan 2003 Smart Optics Faraday Partnership 1 Smart Optics

    E-Print Network [OSTI]

    Greenaway, Alan

    27 Jan 2003 Smart Optics Faraday Partnership 1 Smart Optics Technologies, Techniques and Space Applications Alan Greenaway Physics, EPS Heriot-Watt University #12;27 Jan 2003 Smart Optics Faraday Partnership 2 Smart? · The Smart Optics Faraday Partnership interprets `Smart Optics' to mean: ­ `... includes

  11. NONLINEAR OPTICS AT INTERFACES

    E-Print Network [OSTI]

    Chen, Chenson K.

    2010-01-01

    Surface Plasmons at a Metal-Dielectric Interface . . . .Plasmons at Metal-Dielectric Interfaces . . . . A. GeneralNONLINEAR OPTICS AT INTERFACES Chenson K. Chen (Ph.D.

  12. Ground-state wave function of plutonium in PuSb as determined via x-ray magnetic circular dichroism

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Janoschek, M.; Haskel, D.; Fernandez-Rodriguez, J.; van Veenendaal, M.; Rebizant, J.; Lander, G. H.; Zhu, J. -X.; Thompson, J. D.; Bauer, E. D.

    2015-01-14

    Measurements of x-ray magnetic circular dichroism (XMCD) and x-ray absorption near-edge structure (XANES) spectroscopy at the Pu M?,? edges of the ferromagnet PuSb are reported. Using bulk magnetization measurements and a sum rule analysis of the XMCD spectra, we determine the individual orbital [?L = 2.8(1)?B/Pu] and spin moments [?S = –2.0(1)?B/Pu] of the Pu 5f electrons for the first time. Atomic multiplet calculations of the XMCD and XANES spectra reproduce well the experimental data and are consistent with the experimental value of the spin moment. These measurements of Lz and Sz are in excellent agreement with the values thatmore »have been extracted from neutron magnetic form factor measurements, and confirm the local character of the 5f electrons in PuSb. We demonstrate that a split M? as well as a narrow M? XMCD signal may serve as a signature of 5f electron localization in actinide compounds.« less

  13. Direct spectroscopic evidence for completely filled Cu 3d shell in BaCu?As? and ? – BaCu?Sb?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wu, S. F.; Richard, P.; van Roekeghem, A.; Nie, S. M.; Miao, H.; Xu, N.; Qian, T.; Saparov, B.; Fang, Z.; Biermann, S.; et al

    2015-06-08

    We use angle-resolved photoemission spectroscopy to extract the band dispersion and the Fermi surface of BaCu?As? and ? - BaCu?Sb?. While the Cu 3d bands in both materials are located around 3.5 eV below the Fermi level, the low-energy photoemission intensity mainly comes from As 4p states, suggesting a completely filled Cu 3d shell. The splitting of the As 3d core levels and the lack of pronounced three-dimensionality in the measured band structure of BaCu?As? indicate a surface state likely induced by the cleavage of this material in the collapsed tetragonal phase, which is consistent with our observation of amore »Cu?¹ oxidation state. However, the observation of Cu states at similar energy in ? - BaCu?Sb? without the pnictide-pnictide interlayer bonding characteristic of the collapsed tetragonal phase suggests that the short interlayer distance in BaCu?As? follows from the stability of the Cu?¹ rather than the other way around. Our results confirm the prediction that BaCu?As? is an sp metal with weak electronic correlations.« less

  14. Ground-state wave function of plutonium in PuSb as determined via x-ray magnetic circular dichroism

    SciTech Connect (OSTI)

    Janoschek, M.; Haskel, D.; Fernandez-Rodriguez, J.; van Veenendaal, M.; Rebizant, J.; Lander, G. H.; Zhu, J. -X.; Thompson, J. D.; Bauer, E. D.

    2015-01-01

    Measurements of x-ray magnetic circular dichroism (XMCD) and x-ray absorption near-edge structure (XANES) spectroscopy at the Pu M?,? edges of the ferromagnet PuSb are reported. Using bulk magnetization measurements and a sum rule analysis of the XMCD spectra, we determine the individual orbital [?L = 2.8(1)?B/Pu] and spin moments [?S = ?2.0(1)?B/Pu] of the Pu 5f electrons for the first time. Atomic multiplet calculations of the XMCD and XANES spectra reproduce well the experimental data and are consistent with the experimental value of the spin moment. These measurements of ?Lz? and ?Sz? are in excellent agreement with the values that have been extracted from neutron magnetic form factor measurements, and confirm the local character of the 5f electrons in PuSb. Finally, we demonstrate that a split M? as well as a narrow M? XMCD signal may serve as a signature of 5f electron localization in actinide compounds.

  15. Pulsed atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1992-10-01

    The design of the Pulsed Atmospheric Fluidized Bed Combustor (PAFBC) as described in the Quarterly Report for the period April--June, 1992 was reviewed and minor modifications were included. The most important change made was in the coal/limestone preparation and feed system. Instead of procuring pre-sized coal for testing of the PAFBC, it was decided that the installation of a milling system would permit greater flexibility in the testing with respect to size distributions and combustion characteristics in the pulse combustor and the fluid bed. Particle size separation for pulse combustor and fluid bed will be performed by an air classifier. The modified process flow diagram for the coal/limestone handling system is presented in Figure 1. The modified process flow diagrams of the fluidized bed/steam cycle and ash handling systems are presented in Figures 2 and 3, respectively.

  16. Development of Atmospheric Monitoring System at Akeno Observatory for the Telescope Array Project

    E-Print Network [OSTI]

    T. Yamamoto; M. Teshima; M. Chikawa; N. Hayashida; S. Kawakami; N. Minagawa; Y. Morizane; M. Sasano; K. Yasui

    2002-08-09

    We have developed an atmospheric monitoring system for the Telescope Array experiment at Akeno Observatory. It consists of a Nd:YAG laser with an alt-azimuth shooting system and a small light receiver. This system is installed inside an air conditioned weather-proof dome. All parts, including the dome, laser, shooter, receiver, and optical devices are fully controlled by a personal computer utilizing the Linux operating system. It is now operated as a back-scattering LIDAR System. For the Telescope Array experiment, to estimate energy reliably and to obtain the correct shower development profile, the light transmittance in the atmosphere needs to be calibrated with high accuracy. Based on observational results using this monitoring system, we consider this LIDAR to be a very powerful technique for Telescope Array experiments. The details of this system and its atmospheric monitoring technique will be discussed.

  17. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    mesoscale oceanic features are current coarse resolutionmesoscale r current variability associated with oceanic ringthe TIW- currents. These mesoscale oceanic and atmospheric

  18. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    mesoscale oceanic features are current coarse resolutionmesoscale r current variability associated with oceanic ringthe TIW- currents. These mesoscale oceanic and atmospheric

  19. Physics Potential of Future Atmospheric Neutrino Searches

    E-Print Network [OSTI]

    Thomas Schwetz

    2008-12-12

    The potential of future high statistics atmospheric neutrino experiments is considered, having in mind currently discussed huge detectors of various technologies (water Cerekov, magnetized iron, liquid Argon). I focus on the possibility to use atmospheric data to determine the octant of $\\theta_{23}$ and the neutrino mass hierarchy. The sensitivity to the $\\theta_{23}$-octant of atmospheric neutrinos is competitive (or even superior) to long-baseline experiments. I discuss the ideal properties of a fictitious atmospheric neutrino detector to determine the neutrino mass hierarchy.

  20. 4, 497545, 2011 atmosphere-wildland

    E-Print Network [OSTI]

    Mandel, Jan

    by the coupling of a mesoscale weather 498 #12;GMDD 4, 497­545, 2011 Coupled atmosphere-wildland model WRF-Fire 3

  1. Impacts of Atmospheric Anthropogenic Nitrogen on the

    E-Print Network [OSTI]

    Ward, Bess

    discharges from wastewater treatment, atmospheric deposition, and so forth, resulting in increasing), including oxidized and reduced inorganic and organic forms. The availability of Nr limits primary pro

  2. Composition and Reactions of Atmospheric Aerosol Particles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth...

  3. Atmospheric chemistry of an Antarctic volcanic plume

    E-Print Network [OSTI]

    2010-01-01

    ET AL. : EREBUS PLUME CHEMISTRY Horrocks, L. A. , C.et al. (2010), Atmospheric chemistry results from the ANTCI2007), Reactive halogen chemistry in volca- nic plumes, J.

  4. Hyperspectral Aerosol Optical Depths from TCAP Flights

    SciTech Connect (OSTI)

    Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

    2013-11-13

    4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the world’s first hyperspectral airborne tracking sunphotometer, acquired aerosol optical depths (AOD) at 1 Hz during all July 2012 flights of the Two Column Aerosol Project (TCAP). Root-mean square differences from AERONET ground-based observations were 0.01 at wavelengths between 500-1020 nm, 0.02 at 380 and 1640 nm and 0.03 at 440 nm in four clear-sky fly-over events, and similar in ground side-by-side comparisons. Changes in the above-aircraft AOD across 3-km-deep spirals were typically consistent with integrals of coincident in situ (on DOE Gulfstream 1 with 4STAR) and lidar (on NASA B200) extinction measurements within 0.01, 0.03, 0.01, 0.02, 0.02, 0.02 at 355, 450, 532, 550, 700, 1064 nm, respectively, despite atmospheric variations and combined measurement uncertainties. Finer vertical differentials of the 4STAR measurements matched the in situ ambient extinction profile within 14% for one homogeneous column. For the AOD observed between 350-1660 nm, excluding strong water vapor and oxygen absorption bands, estimated uncertainties were ~0.01 and dominated by (then) unpredictable throughput changes, up to +/-0.8%, of the fiber optic rotary joint. The favorable intercomparisons herald 4STAR’s spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

  5. AN INTRODUCTION TO QUANTUM OPTICS...

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    AN INTRODUCTION TO QUANTUM OPTICS... ...the light as you've never seen before... Optics:http://science.howstuffworks.com/laser5.htm #12;5 DEFINITION Quantum Optics: "Quantum optics is a field in quantum physics, dealing OPTICS OPERATORS Light is described in terms of field operators for creation and annihilation of photons

  6. SEARCH FOR RAYLEIGH SCATTERING IN THE ATMOSPHERE OF GJ1214b

    SciTech Connect (OSTI)

    De Mooij, E. J. W.; Jayawardhana, R. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Brogi, M.; Snellen, I. A. G.; Hoekstra, H.; Otten, G. P. P. L.; Bekkers, D. H.; Haffert, S. Y.; Van Houdt, J. J. [Leiden Observatory, Leiden University, Postbus 9513, 2300-RA, Leiden (Netherlands); De Kok, R. J. [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584-CA, Utrecht (Netherlands); Croll, B., E-mail: demooij@astro.utoronto.ca [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2013-07-10

    We investigate the atmosphere of GJ1214b, a transiting super-Earth planet with a low mean density, by measuring its transit depth as a function of wavelength in the blue optical portion of the spectrum. It is thought that this planet is either a mini-Neptune, consisting of a rocky core with a thick, hydrogen-rich atmosphere, or a planet with a composition dominated by water. Most observations favor a water-dominated atmosphere with a small scale-height, however, some observations indicate that GJ1214b could have an extended atmosphere with a cloud layer muting the molecular features. In an atmosphere with a large scale-height, Rayleigh scattering at blue wavelengths is likely to cause a measurable increase in the apparent size of the planet toward the blue. We observed the transit of GJ1214b in the B band with the FOcal Reducing Spectrograph at the Very Large Telescope and in the g band with both ACAM on the William Herschel Telescope (WHT) and the Wide Field Camera at the Isaac Newton Telescope (INT). We find a planet-to-star radius ratio in the B band of 0.1162 {+-} 0.0017, and in the g band 0.1180 {+-} 0.0009 and 0.1174 {+-} 0.0017 for the WHT and INT observations, respectively. These optical data do not show significant deviations from previous measurements at longer wavelengths. In fact, a flat transmission spectrum across all wavelengths best describes the combined observations. When atmospheric models are considered, a small scale-height water-dominated model fits the data best.

  7. Response of global soil consumption of atmospheric methane to changes in atmospheric climate and nitrogen deposition

    E-Print Network [OSTI]

    Zhuang, Qianlai

    Soil consumption of atmospheric methane plays an important secondary role in regulating the atmospheric CH4 budget, next to the dominant loss mechanism involving reaction with the hydroxyl radical (OH). Here we used a ...

  8. Dual frequency optical cavity

    DOE Patents [OSTI]

    George, E. Victor (Livermore, CA); Schipper, John F. (Palo Alto, CA)

    1985-01-01

    Method and apparatus for generating two distinct laser frequencies in an optical cavity, using a "T" configuration laser cavity and means for intermittently increasing or decreasing the index of refraction n of an associated transmission medium in one arm of the optical cavity to enhance laser action in one arm or the second arm of the cavity.

  9. Optical scanning apparatus

    DOE Patents [OSTI]

    Villarreal, R.A.

    1985-11-06

    An optical scanner employed in a radioactive environment for reading indicia imprinted about a cylindrical surface of an article by means of an optical system including metallic reflective and mirror surfaces resistant to degradation and discoloration otherwise imparted to glass surfaces exposed to radiation is described.

  10. Fiber optic hydrophone

    DOE Patents [OSTI]

    Kuzmenko, Paul J. (Livermore, CA); Davis, Donald T. (Livermore, CA)

    1994-01-01

    A miniature fiber optic hydrophone based on the principles of a Fabry-Perot interferometer. The hydrophone, in one embodiment, includes a body having a shaped flexible bladder at one end which defines a volume containing air or suitable gas, and including a membrane disposed adjacent a vent. An optic fiber extends into the body with one end terminating in spaced relation to the membrane. Acoustic waves in the water that impinge on the bladder cause the pressure of the volume therein to vary causing the membrane to deflect and modulate the reflectivity of the Fabry-Perot cavity formed by the membrane surface and the cleaved end of the optical fiber disposed adjacent to the membrane. When the light is transmitted down the optical fiber, the reflected signal is amplitude modulated by the incident acoustic wave. Another embodiment utilizes a fluid filled volume within which the fiber optic extends.

  11. Optically Induced Transparency

    E-Print Network [OSTI]

    Zheng, Yuanlin; Shen, Zhenhua; Cao, Jianjun; Chen, Xianfeng; Liang, Xiaogan; Wan, Wenjie

    2015-01-01

    Light-matter-light interactions serve as the backbone technology of all-optical information processing for both on-chip and long-haul communication purposes. The representative example of electromagnetically induced transparency has its unique ability of optically controlling transparency windows with relative low light in atomic systems, though its practical applications are limited due to rigid experimental requirements. Here we demonstrate a new form of optically induced transparency in a micro-cavity by introducing four-wave mixing gain in order to couple nonlinearly two separated resonances of the micro-cavity in ambient environment. A signature Fano-like resonance is also observed owing to the nonlinear interference of two coupled resonances. Moreover, we show that the unidirectional gain of four-wave mixing can lead to non-reciprocal transmission at the transparency windows. Optically induced transparency may offer a unique platform for a compact, integrated solution to all-optical processing and quant...

  12. Digital optical conversion module

    DOE Patents [OSTI]

    Kotter, D.K.; Rankin, R.A.

    1988-07-19

    A digital optical conversion module used to convert an analog signal to a computer compatible digital signal including a voltage-to-frequency converter, frequency offset response circuitry, and an electrical-to-optical converter. Also used in conjunction with the digital optical conversion module is an optical link and an interface at the computer for converting the optical signal back to an electrical signal. Suitable for use in hostile environments having high levels of electromagnetic interference, the conversion module retains high resolution of the analog signal while eliminating the potential for errors due to noise and interference. The module can be used to link analog output scientific equipment such as an electrometer used with a mass spectrometer to a computer. 2 figs.

  13. Fiber optic hydrophone

    DOE Patents [OSTI]

    Kuzmenko, P.J.; Davis, D.T.

    1994-05-10

    A miniature fiber optic hydrophone based on the principles of a Fabry-Perot interferometer is disclosed. The hydrophone, in one embodiment, includes a body having a shaped flexible bladder at one end which defines a volume containing air or suitable gas, and including a membrane disposed adjacent a vent. An optical fiber extends into the body with one end terminating in spaced relation to the membrane. Acoustic waves in the water that impinge on the bladder cause the pressure of the volume therein to vary causing the membrane to deflect and modulate the reflectivity of the Fabry-Perot cavity formed by the membrane surface and the cleaved end of the optical fiber disposed adjacent to the membrane. When the light is transmitted down the optical fiber, the reflected signal is amplitude modulated by the incident acoustic wave. Another embodiment utilizes a fluid filled volume within which the fiber optic extends. 2 figures.

  14. Shallow to deep transformation of Se donors in GaSb under hydrostatic pressure H. Navarro-Contreras, F. de Anda-Salazar, and J. Olvera-Hernandez

    E-Print Network [OSTI]

    McCluskey, Matthew

    Shallow to deep transformation of Se donors in GaSb under hydrostatic pressure H. Navarro, although it may be also an indication that the Se shallow donors change to deep donors associated pressures above a certain threshold value. The DX center is a deep-level defect found in many n

  15. Limitations on Subcontracting Service-Disabled Veteran-Owned SB Set-Aside UT-B Contracts Div Page 1 of 1

    E-Print Network [OSTI]

    Limitations on Subcontracting ­ Service-Disabled Veteran-Owned SB Set-Aside UT-B Contracts Div Mar LIMITATIONS ON SUBCONTRACTING ­ SERVICE-DISABLED VETERAN-OWNED SMALL BUSINESS SET-ASIDE OR SOLE SOURCE AWARD of other service-disabled veteran-owned small business concerns. (b) Supplies (other than procurement from

  16. A simple production-consumption system This note is for SB200, "A systems approach to biology". It provides more details of the analysis

    E-Print Network [OSTI]

    Gunawardena, Jeremy

    A simple production-consumption system This note is for SB200, "A systems approach to biology". It provides more details of the analysis of the production-consumption system that was done in the first to one of the TAs. I explained in class how the production-consumption system leads to the differential

  17. Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge2Sb2Te5 and GeTe

    E-Print Network [OSTI]

    Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge and computer memory, but the structure of the amorphous phases and the nature of the phase transition of types A Ge and Sb and B Te , an "ABAB square." The rapid amorphous-to-crystalline phase change

  18. Comparison of Pb, Zn, Cd, As, Cr, Mo and Sb Adsorption onto Natural Surface Coatings in a Stream Draining Natural As

    E-Print Network [OSTI]

    Comparison of Pb, Zn, Cd, As, Cr, Mo and Sb Adsorption onto Natural Surface Coatings in a Stream Science+Business Media New York 2014 Abstract Natural surface coatings (biofilms) were col- lected elements Á Distribution coefficient Á Biogenic Mn oxide Natural surface coatings are ubiquitous

  19. ZnO:Sb/ZnO:Ga Light Emitting Diode on c-Plane Sapphire by Molecular Beam Epitaxy Zheng Yang, Sheng Chu, Winnie V. Chen1

    E-Print Network [OSTI]

    Yang, Zheng

    ZnO:Sb/ZnO:Ga Light Emitting Diode on c-Plane Sapphire by Molecular Beam Epitaxy Zheng Yang, Sheng substrates using plasma-assisted molecular-beam epitaxy. Mesa geometry light emitting diodes (LEDs) were demonstrated in recent years, such as photodetectors,8,9) light-emitting diodes (LEDs),10­13) and random lasing

  20. Evolution of glass properties during a substitution of S by Se in Ge28Sb12S60-xSex glass Guillaume Guery1,2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Evolution of glass properties during a substitution of S by Se in Ge28Sb12S60-xSex glass network, Université de Bordeaux I, Avenue du Dr Schweitzer, 33608 Pessac Cedex, France. Keywords: Chalcogenide glass; Raman spectroscopy; X-ray photoelectron spectroscopy; Glass properties Author whom correspondence should

  1. 504 IEEE ELECTRON DEVICE LETTERS, VOL. 33, NO. 4, APRIL 2012 Ultrathin-Body High-Mobility InAsSb-on-Insulator

    E-Print Network [OSTI]

    Javey, Ali

    504 IEEE ELECTRON DEVICE LETTERS, VOL. 33, NO. 4, APRIL 2012 Ultrathin-Body High-Mobility In- effect transistors (FETs) with ultrahigh electron mobilities are reported. The devices are obtainedAsSb-on-insulator FETs exhibit an effective mobility of 3400 cm2 /V · s for a body thickness of 7 nm, which rep- resents

  2. ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2013)

    E-Print Network [OSTI]

    Lee, Sukyoung

    2013-01-01

    ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2013) Published online in Wiley Online Library Sciences, Seoul National University, Seoul, South Korea *Correspondence to: C. Yoo, Center for Atmosphere). A number of studies have shown that the MJO plays an important role in modulating the extratropical cir

  3. Stellar Atmospheres, Ht 2007 Problem Set 1

    E-Print Network [OSTI]

    Korn, Andreas

    Stellar Atmospheres, Ht 2007 Problem Set 1 Due date: Monday, 24 September 2007 at 10.15 1. LTE of how temperature is defined. (b) Where in the solar atmosphere would you expect the strongest for the photosphere? (c) How does the relation between matter and radiation differ between LTE and NLTE? What must

  4. Results from the Phoenix Atmospheric Structure Experiment

    E-Print Network [OSTI]

    Withers, Paul

    Results from the Phoenix Atmospheric Structure Experiment Paul Withers1 and David Catling2 (1 and atmospheric structure reconstruction for Phoenix · Highlight selected aspects of Phoenix reconstruction reconstruction for Phoenix · Highlight selected aspects of Phoenix reconstruction that offer lessons for future

  5. Geochemistry of Surface-Atmosphere Interactions on

    E-Print Network [OSTI]

    Withers, Paul

    , T, and atmospheric composition ¥ ...Kinetics ¥ What are the major minerals? ¥ What is the oxidation of terrestrial alkaline igneous rocks #12;Oxidation State of the Surface ¥ 2CO + O2 = 2CO2 controls O2 ¥ Lack. ¥ S in lower atmosphere is kinetically controlled ¥ CaCO3 + SO2 = CaSO4 + CO removes SO2 , deposits CaSO4 ¥ Fe

  6. Design of a differential radiometer for atmospheric radiative flux measurements

    SciTech Connect (OSTI)

    LaDelfe, P.C.; Weber, P.G.; Rodriguez, C.W.

    1994-11-01

    The Hemispherical Optimized NEt Radiometer (HONER) is an instrument under development at the Los Alamos National Laboratory for deployment on an unmanned aerospace vehicle as part of the Atmospheric Radiation Measurements (ARM/UAV) program. HONER is a differential radiometer which will measure the difference between the total upwelling and downwelling fluxes and is intended to provide a means of measuring the atmospheric radiative flux divergence. Unlike existing instruments which measure the upwelling and downwelling fluxes separately, HONER will achieve an optical difference by chopping the two fluxes alternately onto a common pyroelectric detector. HONER will provide data resolved into two spectral bands; one covering the solar dominated region from less than 0.4 micrometer to approximately 4.5 micrometers and the other covering the region from approximately 4.5 micrometers to greater than 50 micrometers, dominated by thermal radiation. The means of separating the spectral regions guarantees seamless summation to calculate the total flux. The fields-of-view are near-hemispherical, upward and downward. The instrument can be converted, in flight, from the differential mode to absolute mode, measuring the upwelling and downwelling fluxes separately and simultaneously. The instrument also features continuous calibration from on-board sources. We will describe the design and operation of the sensor head and the on-board reference sources as well as the means of deployment.

  7. Atmospheric-pressure plasma decontamination/sterilization chamber

    DOE Patents [OSTI]

    Herrmann, Hans W. (Los Alamos, NM); Selwyn, Gary S. (Los Alamos, NM)

    2001-01-01

    An atmospheric-pressure plasma decontamination/sterilization chamber is described. The apparatus is useful for decontaminating sensitive equipment and materials, such as electronics, optics and national treasures, which have been contaminated with chemical and/or biological warfare agents, such as anthrax, mustard blistering agent, VX nerve gas, and the like. There is currently no acceptable procedure for decontaminating such equipment. The apparatus may also be used for sterilization in the medical and food industries. Items to be decontaminated or sterilized are supported inside the chamber. Reactive gases containing atomic and metastable oxygen species are generated by an atmospheric-pressure plasma discharge in a He/O.sub.2 mixture and directed into the region of these items resulting in chemical reaction between the reactive species and organic substances. This reaction typically kills and/or neutralizes the contamination without damaging most equipment and materials. The plasma gases are recirculated through a closed-loop system to minimize the loss of helium and the possibility of escape of aerosolized harmful substances.

  8. High-Temperature Thermoelectric Properties of the Solid–Solution Zintl Phase Eu11Cd6Sb12–xAsx (x < 3)

    SciTech Connect (OSTI)

    Kazem, Nasrin; Xie, Weiwei; Ohno, Saneyuki; Zevalkink, Alexandra; Miller, Gordon J; Snyder, G Jeffrey; Kauzlarich, Susan M

    2014-02-11

    Zintl phases are compounds that have shown promise for thermoelectric applications. The title solid–solution Zintl compounds were prepared from the elements as single crystals using a tin flux for compositions x = 0, 1, 2, and 3. Eu11Cd6Sb12–xAsx (x < 3) crystallize isostructurally in the centrosymmetric monoclinic space group C2/m (no. 12, Z = 2) as the Sr11Cd6Sb12 structure type (Pearson symbol mC58). Efforts to make the As compositions for x exceeding ?3 resulted in structures other than the Sr11Cd6Sb12 structure type. Single-crystal X-ray diffraction indicates that As does not randomly substitute for Sb in the structure but is site specific for each composition. The amount of As determined by structural refinement was verified by electron microprobe analysis. Electronic structures and energies calculated for various model structures of Eu11Cd6Sb10As2 (x = 2) indicated that the preferred As substitution pattern involves a mixture of three of the six pnicogen sites in the asymmetric unit. In addition, As substitution at the Pn4 site opens an energy gap at the Fermi level, whereas substitution at the other five pnicogen sites remains semimetallic with a pseudo gap. Thermoelectric properties of these compounds were measured on hot-pressed, fully densified pellets. Samples show exceptionally low lattice thermal conductivities from room temperature to 775 K: 0.78–0.49 W/mK for x = 0; 0.72–0.53 W/mK for x = 1; and 0.70–0.56 W/mK for x = 2. Eu11Cd6Sb12 shows a high p-type Seebeck coefficient (from +118 to 153 ? V/K) but also high electrical resistivity (6.8 to 12.8 m?·cm). The value of zT reaches 0.23 at 774 K. The properties of Eu11Cd6Sb12–xAsx are interpreted in discussion with the As site substitution.

  9. Atmospheric sampling glow discharge ionization source

    DOE Patents [OSTI]

    McLuckey, S.A.; Glish, G.L.

    1989-07-18

    An atmospheric sampling glow discharge ionization source that can be used in combination with an analytical instrument which operates at high vacuum, such as a mass spectrometer. The atmospheric sampling glow discharge ionization source comprises a chamber with at least one pair of electrodes disposed therein, an inlet for a gaseous sample to be analyzed and an outlet communicating with an analyzer which operates at subatmospheric pressure. The ionization chamber is maintained at a pressure below atmospheric pressure, and a voltage difference is applied across the electrodes to induce a glow discharge between the electrodes, so that molecules passing through the inlet are ionized by the glow discharge and directed into the analyzer. The ionization source accepts the sample under atmospheric pressure conditions and processes it directly into the high vacuum instrument, bridging the pressure gap and drawing off unwanted atmospheric gases. The invention also includes a method for analyzing a gaseous sample using the glow discharge ionization source described above. 3 figs.

  10. Observation and modeling of polycrystalline grain formation in Ge{sub 2}Sb{sub 2}Te{sub 5}

    SciTech Connect (OSTI)

    Burr, Geoffrey W.; Tchoulfian, Pierre; Topuria, Teya; Nyffeler, Clemens; Virwani, Kumar; Padilla, Alvaro; Shelby, Robert M.; Eskandari, Mona; Jackson, Bryan; Lee, Bong-Sub

    2012-05-15

    The relationship between the polycrystalline nature of phase change materials (such as Ge{sub 2}Sb{sub 2}Te{sub 5}) and the intermediate resistance states of phase change memory (PCM) devices has not been widely studied. A full understanding of such states will require knowledge of how polycrystalline grains form, how they interact with each other at various temperatures, and how the differing electrical (and thermal) characteristics within the grains and at their boundaries combine through percolation to produce the externally observed electrical (and thermal) characteristics of a PCM device. We address the first of these tasks (and introduce a vehicle for the second) by studying the formation of fcc polycrystalline grains from the as-deposited amorphous state in undoped Ge{sub 2}Sb{sub 2}Te{sub 5}. We perform ex situ transmission electron microscopy membrane experiments and then match these observations against numerical simulation. Ramped-anneal experiments show that the temperature ramp-rate strongly influences the median grain size. By truncating such ramped-anneal experiments at various peak temperatures, we convincingly demonstrate that the temperature range over which these grains are established is quite narrow. Subsequent annealing at elevated temperature appears to change these established distributions of grain sizes only slightly. Our numerical simulator--which models nuclei formation through classical nucleation theory and then tracks the subsequent time- and temperature-dependent growth of these grains--can match these experimental observations of initial grain distributions and crystallization temperature both qualitatively and quantitatively. These simulations show that the particular narrow temperature range over which crystallization occurs shifts as a function of temperature ramp-rate, which allows us to quantify the lower portions of the time-temperature-transformation map for Ge{sub 2}Sb{sub 2}Te{sub 5}. Future experiments and extensions of the simulator to investigate temperature-dependent interactions between neighboring grains, and to study nucleation from within the melt-quenched amorphous state, are discussed.

  11. Bringing Optical Metamaterials to Reality

    E-Print Network [OSTI]

    Valentine, Jason Gage

    2010-01-01

    refraction in bulk metamaterials of nanowires. ," Science ,Optical negative-index metamaterials," Nature Photonics ,Optical negative-index bulk metamaterials consisting of 2D

  12. Non-equilibrium atmospheric pressure microplasma jet: An approach to endoscopic therapies

    SciTech Connect (OSTI)

    Zuo, Xiao; Wei, Yu; Wei Chen, Long; Dong Meng, Yue; Collaboration: Plasma Medicine Team

    2013-08-15

    Atmospheric pressure microplasma jet generated in a long hollow core optical fiber is studied to verify the potential feasibility of endoscopic therapies. Thermal damage and electric shock to the human body were suppressed by two technical methods, i.e., the high-voltage resistant flexible tube wrapped on the optical fiber and a power resistor of 100 k? connected between the power supply and the copper foil electrode. Optical emission spectra analysis indicated that many kinds of active radicals like excited atomic O and OH, were generated in the microplasma jet. In addition, the applications of the microplasma jet on sterilization and lung cancer cell apoptosis were presented. After 5 min of exposures to the microplasma jet, the cell viability and the bacillus subtilis replication decreased to about 3% and zero, respectively. More investigations are needed to improve the plasma-aided endoscopic therapies.

  13. Projection optics box

    DOE Patents [OSTI]

    Hale, Layton C. (Livermore, CA); Malsbury, Terry (Tracy, CA); Hudyma, Russell M. (San Ramon, CA); Parker, John M. (Tracy, CA)

    2000-01-01

    A projection optics box or assembly for use in an optical assembly, such as in an extreme ultraviolet lithography (EUVL) system using 10-14 nm soft x-ray photons. The projection optics box utilizes a plurality of highly reflective optics or mirrors, each mounted on a precision actuator, and which reflects an optical image, such as from a mask, in the EUVL system onto a point of use, such as a target or silicon wafer, the mask, for example, receiving an optical signal from a source assembly, such as a developed from laser system, via a series of highly reflective mirrors of the EUVL system. The plurality of highly reflective optics or mirrors are mounted in a housing assembly comprised of a series of bulkheads having wall members secured together to form a unit construction of maximum rigidity. Due to the precision actuators, the mirrors must be positioned precisely and remotely in tip, tilt, and piston (three degrees of freedom), while also providing exact constraint.

  14. Trends in Electrical Transport of p-type Skutterudites RFe4Sb12 (R-Na,K,Ca,Sr,Ba,La,Ce,Pr,Yb) from First Principles Calculations and Boltzmann Transport Theory

    SciTech Connect (OSTI)

    Yang, Jiong [Chinese Academy of Sciences; Qiu, P [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Liu, R [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Xi, L [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Zheng, S [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Zhang, W [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Chen, Lidong [Chinese Academy of Sciences; Singh, David J [ORNL

    2011-01-01

    We report a consistent set of ab initio calculations of the electronic structures and electrical transport properties of p-type thermoelectric compounds RFe{sub 4}Sb{sub 12}, where R is a rattling filler selected from alkali metals (Na, K), alkaline earths (Ca, Sr, Ba), and rare earth metals (La, Ce, Pr, Yb). Different from the single Sb-dominated light band in the valence band edge of CoSb{sub 3}, the heavy bands from Fe d electronic states also fall in the energy range close to the valence band edges in the RFe{sub 4}Sb{sub 12}. These heavy bands dominate the band-edge density of states, pin the Fermi levels, and mostly determine the electrical transport properties of those p-type RFe{sub 4}Sb{sub 12}. The Seebeck coefficients can be roughly categorized into three groups based on the charge states of fillers, and the maxima are lower than those of n-type CoSb{sub 3} skutterudites. Effective carrier relaxation time in p-type RFe{sub 4}Sb{sub 12}, obtained from the combinations of calculations and experiments, is remarkably similar among different compounds with values around 7.5 x 10{sup -15} s and weak temperature dependence. The optimal doping levels of those RFe{sub 4}Sb{sub 12} are estimated to be around 0.6-0.8 holes per unit cell at 850 K, which is difficult to achieve in RFe{sub 4}Sb{sub 12} compounds. Prospects for further improving the performance of p-type skutterudites are also discussed.

  15. Gregorian optical system with non-linear optical technology for protection against intense optical transients

    DOE Patents [OSTI]

    Ackermann, Mark R. (Albuquerque, NM); Diels, Jean-Claude M. (Albuquerque, NM)

    2007-06-26

    An optical system comprising a concave primary mirror reflects light through an intermediate focus to a secondary mirror. The secondary mirror re-focuses the image to a final image plane. Optical limiter material is placed near the intermediate focus to optically limit the intensity of light so that downstream components of the optical system are protected from intense optical transients. Additional lenses before and/or after the intermediate focus correct optical aberrations.

  16. Scalable optical quantum computer

    SciTech Connect (OSTI)

    Manykin, E A; Mel'nichenko, E V [Institute for Superconductivity and Solid-State Physics, Russian Research Centre 'Kurchatov Institute', Moscow (Russian Federation)

    2014-12-31

    A way of designing a scalable optical quantum computer based on the photon echo effect is proposed. Individual rare earth ions Pr{sup 3+}, regularly located in the lattice of the orthosilicate (Y{sub 2}SiO{sub 5}) crystal, are suggested to be used as optical qubits. Operations with qubits are performed using coherent and incoherent laser pulses. The operation protocol includes both the method of measurement-based quantum computations and the technique of optical computations. Modern hybrid photon echo protocols, which provide a sufficient quantum efficiency when reading recorded states, are considered as most promising for quantum computations and communications. (quantum computer)

  17. Optical limiting materials

    DOE Patents [OSTI]

    McBranch, D.W.; Mattes, B.R.; Koskelo, A.C.; Heeger, A.J.; Robinson, J.M.; Smilowitz, L.B.; Klimov, V.I.; Cha, M.; Sariciftci, N.S.; Hummelen, J.C.

    1998-04-21

    Methanofullerenes, fulleroids and/or other fullerenes chemically altered for enhanced solubility, in liquid solution, and in solid blends with transparent glass (SiO{sub 2}) gels or polymers, or semiconducting (conjugated) polymers, are shown to be useful as optical limiters (optical surge protectors). The nonlinear absorption is tunable such that the energy transmitted through such blends saturates at high input energy per pulse over a wide range of wavelengths from 400--1,100 nm by selecting the host material for its absorption wavelength and ability to transfer the absorbed energy into the optical limiting composition dissolved therein. This phenomenon should be generalizable to other compositions than substituted fullerenes. 5 figs.

  18. Fiber optic laser rod

    DOE Patents [OSTI]

    Erickson, G.F.

    1988-04-13

    A laser rod is formed from a plurality of optical fibers, each forming an individual laser. Synchronization of the individual fiber lasers is obtained by evanescent wave coupling between adjacent optical fiber cores. The fiber cores are dye-doped and spaced at a distance appropriate for evanescent wave coupling at the wavelength of the selected dye. An interstitial material having an index of refraction lower than that of the fiber core provides the optical isolation for effective lasing action while maintaining the cores at the appropriate coupling distance. 2 figs.

  19. Silicon fiber optic sensors

    DOE Patents [OSTI]

    Pocha, Michael D. (Livermore, CA); Swierkowski, Steve P. (Livermore, CA); Wood, Billy E. (Livermore, CA)

    2007-10-02

    A Fabry-Perot cavity is formed by a partially or wholly reflective surface on the free end of an integrated elongate channel or an integrated bounding wall of a chip of a wafer and a partially reflective surface on the end of the optical fiber. Such a constructed device can be utilized to detect one or more physical parameters, such as, for example, strain, through the optical fiber using an optical detection system to provide measuring accuracies of less than aboutb0.1%.

  20. Studying atmosphere-dominated hot Jupiter Kepler phase curves: Evidence that inhomogeneous atmospheric reflection is common

    E-Print Network [OSTI]

    Shporer, Avi

    2015-01-01

    We identify 3 Kepler transiting planet systems, Kepler-7, Kepler-12, and Kepler-41, whose orbital phase-folded light curves are dominated by planetary atmospheric processes including thermal emission and reflected light, while the impact of non-atmospheric (i.e. gravitational) processes, including beaming (Doppler boosting) and tidal ellipsoidal distortion, is negligible. Therefore, those systems allow a direct view of their atmospheres without being hampered by the approximations used in the inclusion of both atmospheric and non-atmospheric processes when modeling the phase curve shape. Here we analyze Kepler-12b and Kepler-41b atmosphere based on their Kepler phase curve, while the analysis of Kepler-7b was presented elsewhere. The model we used efficiently computes reflection and thermal emission contributions to the phase curve, including inhomogeneous atmospheric reflection due to longitudinally varying cloud coverage. We confirm Kepler-12b and Kepler-41b show a westward phase shift between the brightest...

  1. Characteristics of GaAsSb single quantum well lasers emitting near 1.3 {micro}m

    SciTech Connect (OSTI)

    SPAHN,OLGA B.; KLEM,JOHN F.

    2000-02-17

    The authors report data on GaAsSb single quantum well lasers grown on GaAs substrates. Room temperature pulsed emission at 1.275 {micro}m in a 1,250 {micro}m-long device has been observed. Minimum threshold current densities of 535 A/cm{sup 2} were measured in 2000 {micro}m long lasers. The authors also measured internal losses of 2--5 cm{sup {minus}1}, internal quantum efficiencies of 30-38% and characteristic temperature T{sub 0} of 67--77 C. From these parameters a gain constant G{sub 0} of 1,660 cm{sup {minus}1} and a transparency current density J{sub tr} of 134 A/cm{sup 2} were calculated. The results indicate the potential for fabricating 1.3 {micro}m VCSELs from these materials.

  2. Enhancement mechanisms for optical forces in integrated optics

    E-Print Network [OSTI]

    Enhancement mechanisms for optical forces in integrated optics M. L. Povinelli(a) , M. Loncar, Massachusetts Institute of Technology, Cambridge MA 02139 ABSTRACT We investigate the extension of optical micromanipulation to integrated optics. In particular, we consider whether propagating light signals can cause

  3. Adaptive optics enhanced simultaneous en-face optical coherence tomography

    E-Print Network [OSTI]

    Dainty, Chris

    Adaptive optics enhanced simultaneous en-face optical coherence tomography and scanning laser ophthalmoscopy David Merino and Chris Dainty Applied Optics Group, Department of Experimental Physics, National and Adrian Gh. Podoleanu Applied Optics Group, School of Physical Sciences, University of Kent at Canterbury

  4. Methods for globally treating silica optics to reduce optical damage

    DOE Patents [OSTI]

    Miller, Philip Edward; Suratwala, Tayyab Ishaq; Bude, Jeffrey Devin; Shen, Nan; Steele, William Augustus; Laurence, Ted Alfred; Feit, Michael Dennis; Wong, Lana Louie

    2012-11-20

    A method for preventing damage caused by high intensity light sources to optical components includes annealing the optical component for a predetermined period. Another method includes etching the optical component in an etchant including fluoride and bi-fluoride ions. The method also includes ultrasonically agitating the etching solution during the process followed by rinsing of the optical component in a rinse bath.

  5. A lateral optical equilibrium in waveguide-resonator optical force

    E-Print Network [OSTI]

    Fan, Shanhui

    A lateral optical equilibrium in waveguide-resonator optical force Varat Intaraprasonk,1@stanford.edu Abstract: We consider the lateral optical force between a resonator and a waveguide, and study the possibility of an equilibrium that occurs solely from the optical force in such system. We prove analytically

  6. Structural characterization of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} as a function of temperature using neutron powder diffraction and extended X-ray absorption fine structure techniques

    SciTech Connect (OSTI)

    Mansour, A. N.; Wong-Ng, W.; Huang, Q.; Tang, W.; Thompson, A.; Sharp, J.

    2014-08-28

    The structure of Bi{sub 2}Te{sub 3} (Seebeck coefficient Standard Reference Material (SRM™ 3451)) and the related phase Sb{sub 2}Te{sub 3} have been characterized as a function of temperature using the neutron powder diffraction (NPD) and the extended X-ray absorption fine structure (EXAFS) techniques. The neutron structural studies were carried out from 20?K to 300?K for Bi{sub 2}Te{sub 3} and from 10?K to 298?K for Sb{sub 2}Te{sub 3}. The EXAFS technique for studying the local structure of the two compounds was conducted from 19?K to 298?K. Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} are isostructural, with a space group of R3{sup ¯}m. The structure consists of repeated quintuple layers of atoms, Te2-M-Te1-M-Te2 (where M?=?Bi or Sb) stacking along the c-axis of the unit cell. EXAFS was used to examine the bond distances and static and thermal disorders for the first three shells of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} as a function of temperature. The temperature dependencies of thermal disorders were analyzed using the Debye and Einstein models for lattice vibrations. The Debye and Einstein temperatures for the first two shells of Bi{sub 2}Te{sub 3} are similar to those of Sb{sub 2}Te{sub 3} within the uncertainty in the data. However, the Debye and Einstein temperatures for the third shell of Bi-Bi are significantly lower than those of the third shell of Sb-Sb. The Einstein temperature for the third shell is consistent with a soft phonon mode in both Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3}. The lower Einstein temperature of Bi-Bi relative to Sb-Sb is consistent with the lower value of thermal conductivity of Bi{sub 2}Te{sub 3} relative to Sb{sub 2}Te{sub 3}.

  7. Thermoelectric properties of chalcopyrite type CuGaTe{sub 2} and chalcostibite CuSbS{sub 2}

    SciTech Connect (OSTI)

    Kumar Gudelli, Vijay; Kanchana, V., E-mail: kanchana@iith.ac.in [Department of Physics, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram 502 205, Andhra Pradesh (India); Vaitheeswaran, G. [Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, Prof. C. R. Rao Road, Gachibowli, Hyderabad 500 046, Andhra Pradesh (India); Svane, A.; Christensen, N. E. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)

    2013-12-14

    Electronic and transport properties of CuGaTe{sub 2}, a hole-doped ternary copper based chalcopyrite type semiconductor, are studied using calculations within the Density Functional Theory and solving the Boltzmann transport equation within the constant relaxation time approximation. The electronic band structures are calculated by means of the full-potential linear augmented plane wave method, using the Tran-Blaha modified Becke-Johnson potential. The calculated band gap of 1.23?eV is in agreement with the experimental value of 1.2?eV. The carrier concentration- and temperature dependent thermoelectric properties of CuGaTe{sub 2} are derived, and a figure of merit of zT?=?1.69 is obtained at 950?K for a hole concentration of 3.7·10{sup 19}?cm{sup ?3}, in agreement with a recent experimental finding of zT?=?1.4, confirming that CuGaTe{sub 2} is a promising material for high temperature thermoelectric applications. The good thermoelectric performance of p-type CuGaTe{sub 2} is associated with anisotropic transport from a combination of heavy and light bands. Also for CuSbS{sub 2} (chalcostibite), a better performance is obtained for p-type than for n-type doping. The variation of the thermopower as a function of temperature and concentration suggests that CuSbS{sub 2} will be a good thermoelectric material at low temperatures, similarly to the isostructural CuBiS{sub 2} compound.

  8. JournalofGeophysicalResearch: Atmospheres RESEARCH ARTICLE

    E-Print Network [OSTI]

    to optical frequencies, extending to X-rays and gamma rays. The electromagnetic pulse associated to its abundance in nature. Lightning processes radiate impulsive electromagnetic waves from DC

  9. Metasurface optical antireflection coating

    SciTech Connect (OSTI)

    Zhang, Boyang [Univ. of Alabama, Huntsville, AL (United States). Department of Electrical and Computer Engineering.; Hendrickson, Joshua [Air Force Research Lab., Wright Patterson Air Force Base, OH (United States); Nader, Nima [Air Force Research Lab., Wright Patterson Air Force Base, OH (United States); Solid State Scientific Corporation, Nashua, New Hampshire (United States); Chen, Hou -Tong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Center for Integrated Nanotechnologies.; Guo, Junpeng [Univ. of Alabama, Huntsville, AL (United States). Department of Electrical and Computer Engineering.

    2014-12-15

    Light reflection at the boundary of two different media is one of the fundamental phenomena in optics, and reduction of reflection is highly desirable in many optical systems. Traditionally, optical antireflection has been accomplished using single- or multiple-layer dielectric films and graded index surface structures in various wavelength ranges. However, these approaches either impose strict requirements on the refractive index matching and film thickness, or involve complicated fabrication processes and non-planar surfaces that are challenging for device integration. Here, we demonstrate an antireflection coating strategy, both experimentally and numerically, by using metasurfaces with designer optical properties in the mid-wave infrared. Our results show that the metasurface antireflection is capable of eliminating reflection and enhancing transmission over a broad spectral band and a wide incidence angle range. The demonstrated antireflection technique has no requirement on the choice of materials and is scalable to other wavelengths.

  10. Metasurface optical antireflection coating

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Boyang; Hendrickson, Joshua; Nader, Nima; Chen, Hou -Tong; Guo, Junpeng

    2014-12-15

    Light reflection at the boundary of two different media is one of the fundamental phenomena in optics, and reduction of reflection is highly desirable in many optical systems. Traditionally, optical antireflection has been accomplished using single- or multiple-layer dielectric films and graded index surface structures in various wavelength ranges. However, these approaches either impose strict requirements on the refractive index matching and film thickness, or involve complicated fabrication processes and non-planar surfaces that are challenging for device integration. Here, we demonstrate an antireflection coating strategy, both experimentally and numerically, by using metasurfaces with designer optical properties in the mid-wave infrared.more »Our results show that the metasurface antireflection is capable of eliminating reflection and enhancing transmission over a broad spectral band and a wide incidence angle range. The demonstrated antireflection technique has no requirement on the choice of materials and is scalable to other wavelengths.« less

  11. Optical gamma thermometer

    DOE Patents [OSTI]

    Koster, Glen Peter; Xia, Hua; Lee, Boon Kwee

    2013-08-06

    An optical gamma thermometer includes a metal mass having a temperature proportional to a gamma flux within a core of a nuclear reactor, and an optical fiber cable for measuring the temperature of the heated metal mass. The temperature of the heated mass may be measured by using one or more fiber grating structures and/or by using scattering techniques, such as Raman, Brillouin, and the like. The optical gamma thermometer may be used in conjunction with a conventional reactor heat balance to calibrate the local power range monitors over their useful in-service life. The optical gamma thermometer occupies much less space within the in-core instrument tube and costs much less than the conventional gamma thermometer.

  12. Erected mirror optical switch

    DOE Patents [OSTI]

    Allen, James J.

    2005-06-07

    A microelectromechanical (MEM) optical switching apparatus is disclosed that is based on an erectable mirror which is formed on a rotatable stage using surface micromachining. An electrostatic actuator is also formed on the substrate to rotate the stage and mirror with a high angular precision. The mirror can be erected manually after fabrication of the device and used to redirect an incident light beam at an arbitrary angel and to maintain this state in the absence of any applied electrical power. A 1.times.N optical switch can be formed using a single rotatable mirror. In some embodiments of the present invention, a plurality of rotatable mirrors can be configured so that the stages and mirrors rotate in unison when driven by a single micromotor thereby forming a 2.times.2 optical switch which can be used to switch a pair of incident light beams, or as a building block to form a higher-order optical switch.

  13. Optical fiber switch

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2002-01-01

    Optical fiber switches operated by electrical activation of at least one laser light modulator through which laser light is directed into at least one polarizer are used for the sequential transport of laser light from a single laser into a plurality of optical fibers. In one embodiment of the invention, laser light from a single excitation laser is sequentially transported to a plurality of optical fibers which in turn transport the laser light to separate individual remotely located laser fuel ignitors. The invention can be operated electro-optically with no need for any mechanical or moving parts, or, alternatively, can be operated electro-mechanically. The invention can be used to switch either pulsed or continuous wave laser light.

  14. Method of fabricating optical waveguides by ion implantation doping

    DOE Patents [OSTI]

    Appleton, B.R.; Ashley, P.R.; Buchal, C.J.

    1987-03-24

    A method for fabricating high-quality optical waveguides in optical quality oxide crystals by ion implantation doping and controlled epitaxial recrystallization is provided. Masked LiNbO/sub 3/ crystals are implanted with high concentrations of Ti dopant at ion energies of about 360 keV while maintaining the crystal near liquid nitrogen temperature. Ion implantation doping produces an amorphous, Ti-rich nonequilibrium phase in the implanted region. Subsequent thermal annealing in a water-saturated oxygen atmosphere at up to 1000/degree/C produces solid-phase epitaxial regrowth onto the crystalline substrate. A high-quality crystalline layer results which incorporates the Ti into the crystal structure at much higher concentrations than is possible by standard diffusion techniques, and this implanted region has excellent optical waveguiding properties.

  15. Toroidal optical activity

    E-Print Network [OSTI]

    Raybould, T A; Papasimakis, N; Kuprov, I; Youngs, I; Chen, W T; Tsai, D P; Zheludev, N I

    2015-01-01

    Optical activity is ubiquitous across natural and artificial media and is conventionally understood in terms of scattering from electric and magnetic moments. Here we demonstrate experimentally and confirm numerically a type of optical activity that cannot be attributed to electric and magnetic multipoles. We show that our observations can only be accounted for by the inclusion of the toroidal dipole moment, the first term of the recently established peculiar family of toroidal multipoles.

  16. PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Photonic RF Waveform Synthesis,

    E-Print Network [OSTI]

    Purdue University

    PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Photonic RF Waveform, Shijun Xiao Funding from ARO, DARPA, and NSF #12;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER performance (spectral engineering, dispersion compensation) #12;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL

  17. PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Andrew M. Weiner and Ehsan Hamidi

    E-Print Network [OSTI]

    Purdue University

    PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Andrew M. Weiner ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Ultrawideband (UWB) Radio-frequency Photonics UWB;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Femtosecond Pulse Shaping A

  18. Fault location in optical networks

    SciTech Connect (OSTI)

    Stevens, Rick C.; Kryzak, Charles J.; Keeler, Gordon A.; Serkland, Darwin K.; Geib, Kent M.; Kornrumpf, William P.

    2008-07-01

    One apparatus embodiment includes an optical emitter and a photodetector. At least a portion of the optical emitter extends a radial distance from a center point. The photodetector provided around at least a portion of the optical emitter and positioned outside the radial distance of the portion of the optical emitter.

  19. The Mathematics of Nonlinear Optics

    E-Print Network [OSTI]

    Métivier, Guy

    The Mathematics of Nonlinear Optics Guy M´etivier March 7, 2009 Contents 1 Introduction 4 2 Examples of equations arising in nonlinear optics 11 3 The framework of hyperbolic systems 18 3.1 Equations Optics 49 5.1 Linear geometric optics . . . . . . . . . . . . . . . . . . . . . . . . . 49 5

  20. Undergraduate Handbook Dear Optics student,

    E-Print Network [OSTI]

    Cantlon, Jessica F.

    Undergraduate Handbook Fall 2013 #12;2 Dear Optics student, It is my great pleasure to welcome you to The Institute of Optics. The Institute of Optics has been educating the next generation of leaders in the field since it was founded in 1929 as the first optics department in the country

  1. SCIENCE, OPTICS & YOU GUIDEBOOK INTRODUCTION

    E-Print Network [OSTI]

    Weston, Ken

    SCIENCE, OPTICS & YOU GUIDEBOOK - i - INTRODUCTION WHAT IS SCIENCE, 0PTICS & YOU? The Science, Optics and You Guidebook is made up as follows: Science, Optics and You is a standards light, color, and optics. Activities are designed to engage students in active investigation

  2. Fibre optics: Forty years later

    SciTech Connect (OSTI)

    Dianov, Evgenii M

    2010-01-31

    This paper presents a brief overview of the state of the art in fibre optics and its main applications: optical fibre communications, fibre lasers and fibre sensors for various physical property measurements. The future of fibre optics and the status of this important area of the modern technology in Russia are discussed. (fiber optics)

  3. Constraining the atmospheric composition of the day-night terminators of HD 189733b: Atmospheric retrieval with aerosols

    SciTech Connect (OSTI)

    Lee, Jae-Min; Irwin, Patrick G. J.; Fletcher, Leigh N.; Barstow, Joanna K.; Heng, Kevin

    2014-07-01

    A number of observations have shown that Rayleigh scattering by aerosols dominates the transmission spectrum of HD 189733b at wavelengths shortward of 1 ?m. In this study, we retrieve a range of aerosol distributions consistent with transmission spectroscopy between 0.3-24 ?m that were recently re-analyzed by Pont et al. To constrain the particle size and the optical depth of the aerosol layer, we investigate the degeneracies between aerosol composition, temperature, planetary radius, and molecular abundances that prevent unique solutions for transit spectroscopy. Assuming that the aerosol is composed of MgSiO{sub 3}, we suggest that a vertically uniform aerosol layer over all pressures with a monodisperse particle size smaller than about 0.1 ?m and an optical depth in the range 0.002-0.02 at 1 ?m provides statistically meaningful solutions for the day/night terminator regions of HD 189733b. Generally, we find that a uniform aerosol layer provide adequate fits to the data if the optical depth is less than 0.1 and the particle size is smaller than 0.1 ?m, irrespective of the atmospheric temperature, planetary radius, aerosol composition, and gaseous molecules. Strong constraints on the aerosol properties are provided by spectra at wavelengths shortward of 1 ?m as well as longward of 8 ?m, if the aerosol material has absorption features in this region. We show that these are the optimal wavelengths for quantifying the effects of aerosols, which may guide the design of future space observations. The present investigation indicates that the current data offer sufficient information to constrain some of the aerosol properties of HD189733b, but the chemistry in the terminator regions remains uncertain.

  4. Oil and gas exploration system and method for detecting trace amounts of hydrocarbon gases in the atmosphere

    DOE Patents [OSTI]

    Wamsley, Paula R. (Littleton, CO); Weimer, Carl S. (Littleton, CO); Nelson, Loren D. (Evergreen, CO); O'Brien, Martin J. (Pine, CO)

    2003-01-01

    An oil and gas exploration system and method for land and airborne operations, the system and method used for locating subsurface hydrocarbon deposits based upon a remote detection of trace amounts of gases in the atmosphere. The detection of one or more target gases in the atmosphere is used to indicate a possible subsurface oil and gas deposit. By mapping a plurality of gas targets over a selected survey area, the survey area can be analyzed for measurable concentration anomalies. The anomalies are interpreted along with other exploration data to evaluate the value of an underground deposit. The system includes a differential absorption lidar (DIAL) system with a spectroscopic grade laser light and a light detector. The laser light is continuously tunable in a mid-infrared range, 2 to 5 micrometers, for choosing appropriate wavelengths to measure different gases and avoid absorption bands of interference gases. The laser light has sufficient optical energy to measure atmospheric concentrations of a gas over a path as long as a mile and greater. The detection of the gas is based on optical absorption measurements at specific wavelengths in the open atmosphere. Light that is detected using the light detector contains an absorption signature acquired as the light travels through the atmosphere from the laser source and back to the light detector. The absorption signature of each gas is processed and then analyzed to determine if a potential anomaly exists.

  5. Embedded fiducials in optical surfaces

    DOE Patents [OSTI]

    Sommargren, Gary E. (Santa Cruz, CA)

    2000-01-01

    Embedded fiducials are provided in optical surfaces and a method for embedding the fiducials. Fiducials, or marks on a surface, are important for optical fabrication and alignment, particularly when individual optical elements are aspheres. Fiducials are used during the course of the polishing process to connect interferometric data, and the equation describing the asphere, to physical points on the optic. By embedding fiducials below the surface of the optic and slightly outside the clear aperture of the optic, the fiducials are not removed by polishing, do not interfere with the polishing process, and do not affect the performance of the finished optic.

  6. Modeling Stellar Atmospheres with a Spherically Symmetric Version of the Atlas Code: Testing the Code by Comparisons to Interferometric Observations and PHOENIX Models

    E-Print Network [OSTI]

    Hilding R. Neilson; John B. Lester

    2008-09-01

    One of the current opportunities for stellar atmospheric modeling is the interpretation of optical interferometric data of stars. Starting from the robust, open source ATLAS atmospheric code (Kurucz, 1979), we have developed a spherically symmetric code, SATLAS, as a new option for modeling stellar atmospheres of low gravity stars. The SATLAS code is tested against both interferometric observations of M giants by Wittkowski and collaborators, and spherically symmetric M giant NextGen models from the PHOENIX code. The SATLAS models predict interferometric visibilities that agree with the observed visibilities and with predicted visibilities, and the SATLAS atmospheric structures also agree with those from spherical PHOENIX models, with just small differences in temperature and pressure at large depths in the atmospheres.

  7. Modeling of Adaptive Optics-Based Free-Space Communications Systems

    SciTech Connect (OSTI)

    Wilks, S C; Morris, J R; Brase, J M; Olivier, S S; Henderson, J R; Thyompson, C; Kartz, M; Ruggiero, A J

    2002-08-06

    We introduce a wave-optics based simulation code written for air-optic laser communications links, that includes a detailed model of an adaptive optics compensation system. We present the results obtained by this model, where the phase of a communications laser beam is corrected, after it propagates through a turbulent atmosphere. The phase of the received laser beam is measured using a Shack-Hartmann wavefront sensor, and the correction method utilizes a MEMS mirror. Strehl improvement and amount of power coupled to the receiving fiber for both 1 km horizontal and 28 km slant paths are presented.

  8. Composition and Reactions of Atmospheric Aerosol Particles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS...

  9. Transport impacts on atmosphere and climate: Aviation

    E-Print Network [OSTI]

    2010-01-01

    Environment 44 (2010) 4678–4734 Brunner, D. , Staehelin,Environment 44 (2010) 4678–4734 Vedantham, A. , Wuebbles,Environment 44 (2010) 4678–4734 global atmosphere’. In:

  10. HYPERsensarium : an archive of atmospheric conditions

    E-Print Network [OSTI]

    Shaw, Kelly E. (Kelly Evelyn)

    2013-01-01

    HYPERsensarium proposes a tangible interface of atmospheres for public experience through an archive of historical and projected weathers. While architecture's purpose has long been to act as the technical boundary between ...

  11. Uraninite and Fullerene in Atmospheric Particulates

    E-Print Network [OSTI]

    Utsunomiya, Satoshi

    incineration, uranium mining, and atmospheric testing of nuclearweapons-burning power plants typically contain very small amounts of uranium ( concentrations, the form of the uranium has been unknown. Using a variety of advanced electron microscopy

  12. Transparent electrode for optical switch

    DOE Patents [OSTI]

    Goldhar, J.; Henesian, M.A.

    1984-10-19

    The invention relates generally to optical switches and techniques for applying a voltage to an electro-optical crystal, and more particularly, to transparent electodes for an optical switch. System architectures for very large inertial confinement fusion (ICF) lasers require active optical elements with apertures on the order of one meter. Large aperture optical switches are needed for isolation of stages, switch-out from regenerative amplifier cavities and protection from target retroreflections.

  13. Fehner and Gosling, Atmospheric Nuclear Weapons Testing, 1951...

    Energy Savers [EERE]

    Atmospheric Nuclear Weapons Testing, 1951-1963. Battlefield of the Cold War: The Nevada Test Site, Volume I Fehner and Gosling, Atmospheric Nuclear Weapons Testing, 1951-1963....

  14. The faculty and students in the Atmospheric Sciences Department use physics, chemistry, and mathematics to better understand the atmosphere

    E-Print Network [OSTI]

    Doty, Sharon Lafferty

    The faculty and students in the Atmospheric Sciences Department use physics, chemistry chemistry Atmospheric fluid dynamics Biosphere interactions Climate variability Clouds & storms Radiative, and mathematics to better understand the atmosphere and improve the prediction of its future state, both over

  15. INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF OPTICS A: PURE AND APPLIED OPTICS Polarization Optics

    E-Print Network [OSTI]

    Friesem, Asher A.

    INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF OPTICS A: PURE AND APPLIED OPTICS EDITORIAL Polarization Optics Guest Editors Jari Turunen University of Joensuu, Finland Asher A Friesem Weizmann Institute This special issue on Polarization Optics contains one review article and 23 research papers, many of which

  16. Atmospheric State, Cloud Microphysics and Radiative Flux

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mace, Gerald

    2008-01-15

    Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.

  17. Air Activation Following an Atmospheric Explosion

    SciTech Connect (OSTI)

    Lowrey, Justin D.; McIntyre, Justin I.; Prichard, Andrew W.; Gesh, Christopher J.

    2013-03-13

    In addition to thermal radiation and fission products, nuclear explosions result in a very high flux of unfissioned neutrons. Within an atmospheric nuclear explosion, these neutrons can activate the various elemental components of natural air, potentially adding to the radioactive signature of the event as a whole. The goal of this work is to make an order-of-magnitude estimate of the total amount of air activation products that can result from an atmospheric nuclear explosion.

  18. Atmospheric State, Cloud Microphysics and Radiative Flux

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mace, Gerald

    Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.

  19. Basalt-Atmosphere Interactions on Venus -

    E-Print Network [OSTI]

    Treiman, Allan H.

    Atmosphere? · CaAl2Si2O8 + SO3 CaSO4 + Al2SiO5 + SiO2 ­ Anhydrite + andalusite + quartz !!! · Does this reaction proceed? ­ Venus atmosphere est'd 0.2 - 0.3 ppt SO3. #12;Reaction Position · From this, very possible that SO3 is buffered! · But ... SO3 value is not known very well - who knows what is really going

  20. Lookup tables to compute high energy cosmic ray induced atmospheric ionization and changes in atmospheric chemistry

    E-Print Network [OSTI]

    Dimitra Atri; Adrian L. Melott; Brian C. Thomas

    2010-05-03

    A variety of events such as gamma-ray bursts and supernovae may expose the Earth to an increased flux of high-energy cosmic rays, with potentially important effects on the biosphere. Existing atmospheric chemistry software does not have the capability of incorporating the effects of substantial cosmic ray flux above 10 GeV . An atmospheric code, the NASA-Goddard Space Flight Center two-dimensional (latitude, altitude) time-dependent atmospheric model (NGSFC), is used to study atmospheric chemistry changes. Using CORSIKA, we have created tables that can be used to compute high energy cosmic ray (10 GeV - 1 PeV) induced atmospheric ionization and also, with the use of the NGSFC code, can be used to simulate the resulting atmospheric chemistry changes. We discuss the tables, their uses, weaknesses, and strengths.

  1. Investigation of arsenic and antimony capping layers, and half cycle reactions during atomic layer deposition of Al{sub 2}O{sub 3} on GaSb(100)

    SciTech Connect (OSTI)

    Zhernokletov, Dmitry M. [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States); Dong, Hong; Brennan, Barry; Kim, Jiyoung; Wallace, Robert M. [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States); Yakimov, Michael; Tokranov, Vadim; Oktyabrsky, Serge [College of Nanoscale Science and Engineering, University at Albany–SUNY, Albany, New York 12203 (United States)] [College of Nanoscale Science and Engineering, University at Albany–SUNY, Albany, New York 12203 (United States)

    2013-11-15

    In-situ monochromatic x-ray photoelectron spectroscopy, low energy electron diffraction, ion scattering spectroscopy, and transmission electron microscopy are used to examine the GaSb(100) surfaces grown by molecular beam epitaxy after thermal desorption of a protective As or Sb layer and subsequent atomic layer deposition (ALD) of Al{sub 2}O{sub 3}. An antimony protective layer is found to be more favorable compared to an arsenic capping layer as it prevents As alloys from forming with the GaSb substrate. The evolution of oxide free GaSb/Al{sub 2}O{sub 3} interface is investigated by “half-cycle” ALD reactions of trimethyl aluminum and deionized water.

  2. Optical assessment of particle size and composition in the Santa Barbara Channel, California

    E-Print Network [OSTI]

    Siegel, David A.

    the carbon cycle, atmospheric carbon dioxide concentration, and, thus, climate [2,3]. Phytoplankton species is important for understanding regional primary productivity and rates of carbon sequestration, the fate, which influence the passive optical remote sensing of the coastal ocean. Here, the extensive bio

  3. Internal solitary waves in the Coastal Mixing and Optics 1996 experiment: Multimodal structure and

    E-Print Network [OSTI]

    Kurapov, Alexander

    and resuspension D. J. Bogucki Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami in sediment resuspension during the Coastal Mixing and Optics 1996 (CMO 96) experiment are reported. The largest resuspension events observed in the experiment can be related to retarded flow under the wave

  4. Atmospheric Neutrinos in the MINOS Far Detector

    SciTech Connect (OSTI)

    Howcroft, Caius L.F.

    2004-12-01

    The phenomenon of flavour oscillations of neutrinos created in the atmosphere was first reported by the Super-Kamiokande collaboration in 1998 and since then has been confirmed by Soudan 2 and MACRO. The MINOS Far Detector is the first magnetized neutrino detector able to study atmospheric neutrino oscillations. Although it was designed to detect neutrinos from the NuMI beam, it provides a unique opportunity to measure the oscillation parameters for neutrinos and anti-neutrinos independently. The MINOS Far Detector was completed in August 2003 and since then has collected 2.52 kton-years of atmospheric data. Atmospheric neutrino interactions contained within the volume of the detector are separated from the dominant background from cosmic ray muons. Thirty seven events are selected with an estimated background contamination of less than 10%. Using the detector's magnetic field, 17 neutrino events and 6 anti-neutrino events are identified, 14 events have ambiguous charge. The neutrino oscillation parameters for {nu}{sub {mu}} and {bar {nu}}{sub {mu}} are studied using a maximum likelihood analysis. The measurement does not place constraining limits on the neutrino oscillation parameters due to the limited statistics of the data set analysed. However, this thesis represents the first observation of charge separated atmospheric neutrino interactions. It also details the techniques developed to perform atmospheric neutrino analyses in the MINOS Far Detector.

  5. Niamey Aerosol Optical Depths

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Flynn, Connor

    2008-10-01

    MFRSR irradiance data collected during the ACRF AMF deployment in Niamey, Niger have been used to derive AOD for five wavelength channels of the MFRSR. These data have been corrected to adjust for filter drift over the course of the campaign and contamination due to forward scattering as a result of large dust particles in the atmosphere around Niamey.

  6. Energy transport, overshoot, and mixing in the atmospheres of very cool stars

    E-Print Network [OSTI]

    H. -G. Ludwig

    2002-08-30

    We constructed hydrodynamical model atmospheres for mid M-type main-, as well as pre-main-sequence objects. Despite the complex chemistry encountered in such cool atmospheres a reasonably accurate representation of the radiative transfer is possible. The detailed treatment of the interplay between radiation and convection in the hydrodynamical models allows to study processes usually not accessible within the framework conventional model atmospheres. In particular, we determined the efficiency of the convective energy transport, and the efficiency of mixing by convective overshoot. The convective transport efficiency expressed in terms of an equivalent mixing-length parameter amounts to values around ~2 in the optically thick, and ~2.8 in the optically thin regime. The thermal structure of the formally convectively stable layers is little affected by convective overshoot and wave heating, i.e. stays close to radiative equilibrium. Mixing by convective overshoot shows an exponential decline with geometrical distance from the Schwarzschild stability boundary. The scale height of the decline varies with gravitational acceleration roughly as g^(-1/2), with 0.5 pressure scale heights at log(g)=5.0.

  7. Fiber optic hydrogen sensor

    DOE Patents [OSTI]

    Buchanan, B.R.; Prather, W.S.

    1991-01-01

    Apparatus and method for detecting a chemical substance by exposing an optic fiber having a core and a cladding to the chemical substance so that the chemical substance can be adsorbed onto the surface of the cladding. The optic fiber is coiled inside a container having a pair of valves for controlling the entrance and exit of the substance. Light from a light source is received by one end of the optic fiber, preferably external to the container, and carried by the core of the fiber. Adsorbed substance changes the transmissivity of the fiber as measured by a spectrophotometer at the other end, also preferably external to the container. Hydrogen is detected by the absorption of infrared light carried by an optic fiber with a silica cladding. Since the adsorption is reversible, a sensor according to the present invention can be used repeatedly. Multiple positions in a process system can be monitored using a single container that can be connected to each location to be monitored so that a sample can be obtained for measurement, or, alternatively, containers can be placed near each position and the optic fibers carrying the partially-absorbed light can be multiplexed for rapid sequential reading, by a single spectrophotometer.

  8. Optical key system

    DOE Patents [OSTI]

    Hagans, Karla G. (Livermore, CA); Clough, Robert E. (Danville, CA)

    2000-01-01

    An optical key system comprises a battery-operated optical key and an isolated lock that derives both its operating power and unlock signals from the correct optical key. A light emitting diode or laser diode is included within the optical key and is connected to transmit a bit-serial password. The key user physically enters either the code-to-transmit directly, or an index to a pseudorandom number code, in the key. Such person identification numbers can be retained permanently, or ephemeral. When a send button is pressed, the key transmits a beam of light modulated with the password information. The modulated beam of light is received by a corresponding optical lock with a photovoltaic cell that produces enough power from the beam of light to operate a password-screen digital logic. In one application, an acceptable password allows a two watt power laser diode to pump ignition and timing information over a fiberoptic cable into a sealed engine compartment. The receipt of a good password allows the fuel pump, spark, and starter systems to each operate. Therefore, bypassing the lock mechanism as is now routine with automobile thieves is pointless because the engine is so thoroughly disabled.

  9. Generalizing Optical Geometry

    E-Print Network [OSTI]

    Rickard Jonsson; Hans Westman

    2007-08-21

    We show that by employing the standard projected curvature as a measure of spatial curvature, we can make a certain generalization of optical geometry (Abramowicz and Lasota 1997, Class. Quantum Grav. 14 (1997) A23). This generalization applies to any spacetime that admits a hypersurface orthogonal shearfree congruence of worldlines. This is a somewhat larger class of spacetimes than the conformally static spacetimes assumed in standard optical geometry. In the generalized optical geometry, which in the generic case is time dependent, photons move with unit speed along spatial geodesics and the sideways force experienced by a particle following a spatially straight line is independent of the velocity. Also gyroscopes moving along spatial geodesics do not precess (relative to the forward direction). Gyroscopes that follow a curved spatial trajectory precess according to a very simple law of three-rotation. We also present an inertial force formalism in coordinate representation for this generalization. Furthermore, we show that by employing a new sense of spatial curvature (Jonsson, Class. Quantum Grav. 23 (2006) 1) closely connected to Fermat's principle, we can make a more extensive generalization of optical geometry that applies to arbitrary spacetimes. In general this optical geometry will be time dependent, but still geodesic photons move with unit speed and follow lines that are spatially straight in the new sense. Also, the sideways experienced (comoving) force on a test particle following a line that is straight in the new sense will be independent of the velocity.

  10. Absolute calibration of optical flats

    DOE Patents [OSTI]

    Sommargren, Gary E.

    2005-04-05

    The invention uses the phase shifting diffraction interferometer (PSDI) to provide a true point-by-point measurement of absolute flatness over the surface of optical flats. Beams exiting the fiber optics in a PSDI have perfect spherical wavefronts. The measurement beam is reflected from the optical flat and passed through an auxiliary optic to then be combined with the reference beam on a CCD. The combined beams include phase errors due to both the optic under test and the auxiliary optic. Standard phase extraction algorithms are used to calculate this combined phase error. The optical flat is then removed from the system and the measurement fiber is moved to recombine the two beams. The newly combined beams include only the phase errors due to the auxiliary optic. When the second phase measurement is subtracted from the first phase measurement, the absolute phase error of the optical flat is obtained.

  11. Using the transit of Venus to probe the upper planetary atmosphere

    E-Print Network [OSTI]

    Reale, Fabio; Micela, Giuseppina; Maggio, Antonio; Widemann, Thomas; Piccioni, Giuseppe

    2015-01-01

    The atmosphere of a transiting planet shields the stellar radiation providing us with a powerful method to estimate its size and density. In particular, because of their high ionization energy, atoms with high atomic number (Z) absorb short-wavelength radiation in the upper atmosphere, undetectable with observations in visible light. One implication is that the planet should appear larger during a primary transit observed in high energy bands than in the optical band. The last Venus transit in 2012 offered a unique opportunity to study this effect. The transit has been monitored by solar space observations from Hinode and Solar Dynamics Observatory (SDO). We measure the radius of Venus during the transit in three different bands with subpixel accuracy: optical (4500A), UV (1600A, 1700A), Extreme UltraViolet (EUV, 171-335A) and soft X-rays (about 10A). We find that, while the Venus optical radius is about 80 km larger than the solid body radius (the expected opacity mainly due to clouds and haze), the radius i...

  12. Optically Reconfigurable Photonic Devices

    E-Print Network [OSTI]

    Wang, Qian; Gholipour, Behrad; Wang, Chih-Ming; Yuan, Guanghui; Teng, Jinghua; Zheludev, Nikolay I

    2015-01-01

    Optoelectronic components with adjustable parameters, from variable-focal-length lenses to spectral filters that can change functionality upon stimulation, have enormous technological importance. Tuning of such components is conventionally achieved by either micro- or nano-mechanical actuation of their consitutive parts, stretching or application of thermal stimuli. Here we report a new dielectric metasurface platform for reconfigurable optical components that are created with light in a non-volatile and reversible fashion. Such components are written, erased and re-written as two-dimensional binary or grey-scale patterns into a nanoscale film of phase change material by inducing a refractive-index-changing phase-transition with tailored trains of femtosecond pulses. We combine germanium-antimony-tellurium-based films optimized for high-optical-contrast ovonic switching with a sub-wavelength-resolution optical writing process to demonstrate technologically relevant devices: visible-range reconfigurable bi-chr...

  13. Explosive boiling of Ge{sub 35}Sb{sub 10}S{sub 55} glass induced by a CW laser

    SciTech Connect (OSTI)

    Knotek, P.; Tichy, L.

    2013-09-01

    Graphical abstract: - Highlights: • Interaction of the CW 785 nm laser with chalcogenide GeSbS glass. • First demonstration of the explosive boiling induced by CW laser in glass. • Different processes as photo-induced oxidation, expansion, and viscosity-flow observed. • Applied diagnostics SEM, DHM, AFM, force spectroscopy, and micro-Raman spectroscopy. • Damage threshold determined at 1.2 × 10{sup 24}s{sup ?1} cm{sup ?3} of absorbed photons. - Abstract: The response of bulk Ge{sub 35}Sb{sub 10}S{sub 55} glass to illumination by a continuous wave (CW) laser, sub-band-gap photons, was studied specifically with an atomic force microscopy including a force spectroscopy, with a digital holographic microscopy and with a scanning electron microscopy. Depending on the number of photons absorbed, photo-expansion, photo-oxidation and explosive boiling were observed.

  14. Annealing effects on structural, electrical and optical properties of antimony-tinoxide thin films deposited by sol gel dip coating technique

    SciTech Connect (OSTI)

    Lekshmy, S. Sujatha, E-mail: jolly2jolly@gmail.com; Anitha, V. S., E-mail: jolly2jolly@gmail.com; Berlin, I. John, E-mail: jolly2jolly@gmail.com; Joy, K., E-mail: jolly2jolly@gmail.com [Thin film Laboratory, Post Graduate and Research Department of Physics, Mar Ivanios College, Thiruvananthapuram 695 015 (India)

    2014-01-28

    Antimony-doped tin dioxide possess interesting physical and chemical properties. These properties have a wide range of applications such as catalysis and optoelectronic devices. In the present study, antimony-doped tin oxide (SnO2:Sb) thin films were deposited on the quartz substrates by sol-gel dip coating technique. The films were annealed at temperatures 350°C, 550°C and 850°C in air for 2 hours. The structure and surface morphologies were observed by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD patterns shows tetragonal structure for the SnO2:Sb films annealed at different temperatures. Crystallite size increased from 6 to 14 nm as annealing temperature increased from 350°C to 850°C. SEM studies reveals crack free and smooth surface for all the films. The grains are found to be homogenously distributed for films annealed at higher temperature. The electrical conductivity of the films annealed at 350°C and 550°C decreased and increased for the films annealed at 850°C. The optical properties of the films were investigated in the UV-visible-NIR region (200-900 nm) using UV spectra. The transmittance of the films decreased for films annealed at higher temperature. The optical energy band gap values (4.13 eV-4.83 eV) increased with the increase in annealing temperature.

  15. Optical plasma microelectronic devices

    E-Print Network [OSTI]

    Forati, Ebrahim; Dill, Thyler; Sievenpiper, Dan

    2015-01-01

    The semiconductor channel in conventional microelectronic devices was successfully replaced with an optically triggered gas plasma channel. The combination of DC and laser-induced gas ionizations controls the conductivity of the channel, enabling us to realize different electronic devices such as transistors, switches, modulators, etc. A special micro-scale metasurface was used to enhance the laser-gas interaction, as well as combining it with DC ionization properly. Optical plasma devices benefit form the advantages of plasma/vacuum electronic devices while preserving most of the integrablity of semiconductor based devices.

  16. Nonimaging optical illumination system

    DOE Patents [OSTI]

    Winston, R.; Ries, H.

    1998-10-06

    A nonimaging illumination optical device for producing a selected far field illuminance over an angular range. The optical device includes a light source a light reflecting surface, and a family of light edge rays defined along a reference line with the reflecting surface defined in terms of the reference lines a parametric function R(t) where t is a scalar parameter position and R(t)=k(t)+Du(t) where k(t) is a parameterization of the reference line, and D is a distance from a point on the reference line to the reflection surface along the desired edge ray through the point. 35 figs.

  17. Nonimaging optical illumination system

    DOE Patents [OSTI]

    Winston, R.; Ries, H.

    1996-12-17

    A nonimaging illumination optical device for producing a selected far field illuminance over an angular range. The optical device includes a light source, a light reflecting surface, and a family of light edge rays defined along a reference line with the reflecting surface defined in terms of the reference line as a parametric function R(t) where t is a scalar parameter position and R(t)=k(t)+Du(t) where k(t) is a parameterization of the reference line, and D is a distance from a point on the reference line to the reflection surface along the desired edge ray through the point. 35 figs.

  18. Record figure of merit values of highly stoichiometric Sb2Te3 porous bulk synthesized from tailor-made molecular precursors in ionic liquids

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Heimann, Stefan; Schulz, Stephan; Schaumann, Julian; Mudring, Anja; Stötzel, Julia; Maculewicz, Franziska; Schierning, Gabi

    2015-08-06

    We report on the synthesis of Sb2Te3 nanoparticles with record-high figure of merit values of up to 1.5. The central thermoelectric parameters, electrical conductivity, thermal conductivity and Seebeck coefficient, were independently optimized. Critical influence of porosity for the fabrication of highly efficient thermoelectric materials is firstly demonstrated, giving a strong guidance for the optimization of other thermoelectric materials.

  19. Cavity quantum electro-optics

    E-Print Network [OSTI]

    Mankei Tsang

    2010-06-30

    The quantum dynamics of the coupling between a cavity optical field and a resonator microwave field via the electro-optic effect is studied. This coupling has the same form as the opto-mechanical coupling via radiation pressure, so all previously considered opto-mechanical effects can in principle be observed in electro-optic systems as well. In particular, I point out the possibilities of laser cooling of the microwave mode, entanglement between the optical mode and the microwave mode via electro-optic parametric amplification, and back-action-evading optical measurements of a microwave quadrature.

  20. Optical Characterization Laboratory (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-10-01

    This fact sheet describes the purpose, lab specifications, applications scenarios, and information on how to partner with NREL's Optical Characterization Laboratory at the Energy Systems Integration Facility. The Optical Characterization Laboratory at NREL's Energy Systems Integration Facility (ESIF) conducts optical characterization of large solar concentration devices. Concentration solar power (CSP) mirror panels and concentrating solar systems are tested with an emphasis is on measurement of parabolic trough mirror panels. The Optical Characterization Laboratory provides state-of-the-art characterization and testing capabilities for assessing the optical surface quality and optical performance for various CSP technologies including parabolic troughs, linear Fresnel, dishes, and heliostats.

  1. Magnetospherically driven optical and radio aurorae at the end of the stellar main sequence

    E-Print Network [OSTI]

    Hallinan, G; Cotter, G; Bourke, S; Harding, L K; Pineda, J S; Butler, R P; Golden, A; Basri, G; Doyle, J G; Kao, M M; Berdyugina, S V; Kuznetsov, A; Rupen, M P; Antonova, A

    2015-01-01

    Aurorae are detected from all the magnetized planets in our Solar System, including Earth. They are powered by magnetospheric current systems that lead to the precipitation of energetic electrons into the high-latitude regions of the upper atmosphere. In the case of the gas-giant planets, these aurorae include highly polarized radio emission at kilohertz and megahertz frequencies produced by the precipitating electrons, as well as continuum and line emission in the infrared, optical, ultraviolet and X-ray parts of the spectrum, associated with the collisional excitation and heating of the hydrogen-dominated atmosphere. Here we report simultaneous radio and optical spectroscopic observations of an object at the end of the stellar main sequence, located right at the boundary between stars and brown dwarfs, from which we have detected radio and optical auroral emissions both powered by magnetospheric currents. Whereas the magnetic activity of stars like our Sun is powered by processes that occur in their lower a...

  2. Optical fiber based ultrashort pulse multispectral nonlinear optical microscopy 

    E-Print Network [OSTI]

    Larson, Adam Michael

    2009-05-15

    Nonlinear optical microscopy (NLOM) utilizing femtosecond laser pulses is well suited for imaging living tissues. This work reports on the design and development of an optical fiber based multispectral NLOM developed around ...

  3. SLUDGE BATCH 7 (SB7) WASHING DEMONSTRATION TO DETERMINE SULFATE/OXALATE REMOVAL EFFICIENCY AND SETTLING BEHAVIOR

    SciTech Connect (OSTI)

    Reboul, S.; Click, D.; Lambert, D.

    2010-12-10

    To support Sludge Batch 7 (SB7) washing, a demonstration of the proposed Tank Farm washing operation was performed utilizing a real-waste test slurry generated from Tank 4, 7, and 12 samples. The purpose of the demonstration was twofold: (1) to determine the settling time requirements and washing strategy needed to bring the SB7 slurry to the desired endpoint; and (2) to determine the impact of washing on the chemical and physical characteristics of the sludge, particularly those of sulfur content, oxalate content, and rheology. Seven wash cycles were conducted over a four month period to reduce the supernatant sodium concentration to approximately one molar. The long washing duration was due to the slow settling of the sludge and the limited compaction. Approximately 90% of the sulfur was removed through washing, and the vast majority of the sulfur was determined to be soluble from the start. In contrast, only about half of the oxalate was removed through washing, as most of the oxalate was initially insoluble and did not partition to the liquid phase until the latter washes. The final sulfur concentration was 0.45 wt% of the total solids, and the final oxalate concentration was 9,900 mg/kg slurry. More oxalate could have been removed through additional washing, although the washing would have reduced the supernatant sodium concentration.The yield stress of the final washed sludge (35 Pa) was an order of magnitude higher than that of the unwashed sludge ({approx}4 Pa) and was deemed potentially problematic. The high yield stress was related to the significant increase in insoluble solids that occurred ({approx}8 wt% to {approx}18 wt%) as soluble solids and water were removed from the slurry. Reduction of the insoluble solids concentration to {approx}14 wt% was needed to reduce the yield stress to an acceptable level. However, depending on the manner that the insoluble solids adjustment was performed, the final sodium concentration and extent of oxalate removal would be prone to change. As such, the strategy for completing the final wash cycle is integral to maintaining the proper balance of chemical and physical requirements.

  4. Optics in data center network architecture

    E-Print Network [OSTI]

    Farrington, Nathan

    2012-01-01

    Chapter 2 Reducing Cabling Complexity with Optics . . . . .Advances in Information Optics and Photonics. SPIE, 2008. [c-Through: Part-time Optics in Data Centers,” in Proceedings

  5. High-index-contrast electromechanical optical switches

    E-Print Network [OSTI]

    Bryant, Reginald (Reginald Eugene), 1978-

    2011-01-01

    System developers are looking to replace protocol-dependent, bandwidth-limited optical networks with intelligent optically-transparent integrated photonic networks. Several electromechanical optical switches are explored ...

  6. 2.71 Optics, Fall 2001

    E-Print Network [OSTI]

    Barbastathis, George

    Introduction to optical science with elementary engineering applications. Geometrical optics: ray-tracing, aberrations, lens design, apertures and stops, radiometry and photometry. Wave optics: basic electrodynamics, ...

  7. Electroforming of Bi(1-x)Sb(x) nanowires for high-efficiency micro-thermoelectric cooling devices on a chip.

    SciTech Connect (OSTI)

    Overmyer, Donald L.; Webb, Edmund Blackburn, III; Siegal, Michael P.; Yelton, William Graham

    2006-11-01

    Active cooling of electronic systems for space-based and terrestrial National Security missions has demanded use of Stirling, reverse-Brayton, closed Joule-Thompson, pulse tube and more elaborate refrigeration cycles. Such cryocoolers are large systems that are expensive, demand large powers, often contain moving parts and are difficult to integrate with electronic systems. On-chip, solid-state, active cooling would greatly enhance the capabilities of future systems by reducing the size, cost and inefficiencies compared to existing solutions. We proposed to develop the technology for a thermoelectric cooler capable of reaching 77K by replacing bulk thermoelectric materials with arrays of Bi{sub 1-x}Sb{sub x} nanowires. Furthermore, the Sandia-developed technique we will use to produce the oriented nanowires occurs at room temperature and can be applied directly to a silicon substrate. Key obstacles include (1) optimizing the Bi{sub 1-x}Sb{sub x} alloy composition for thermoelectric properties; (2) increasing wire aspect ratios to 3000:1; and (3) increasing the array density to {ge} 10{sup 9} wires/cm{sup 2}. The primary objective of this LDRD was to fabricate and test the thermoelectric properties of arrays of Bi{sub 1-x}Sb{sub x} nanowires. With this proof-of-concept data under our belts we are positioned to engage National Security systems customers to invest in the integration of on-chip thermoelectric coolers for future missions.

  8. p-type conduction from Sb-doped ZnO thin films grown by dual ion beam sputtering in the absence of oxygen ambient

    SciTech Connect (OSTI)

    Kumar Pandey, Sushil; Kumar Pandey, Saurabh; Awasthi, Vishnu; Kumar, Ashish; Mukherjee, Shaibal; Deshpande, Uday P.; Gupta, Mukul

    2013-10-28

    Sb-doped ZnO (SZO) thin films were deposited on c-plane sapphire substrates by dual ion beam sputtering deposition system in the absence of oxygen ambient. The electrical, structural, morphological, and elemental properties of SZO thin films were studied for films grown at different substrate temperatures ranging from 200 °C to 600 °C and then annealed in situ at 800 °C under vacuum (pressure ?5 × 10{sup ?8} mbar). Films grown for temperature range of 200–500 °C showed p-type conduction with hole concentration of 1.374 × 10{sup 16} to 5.538 × 10{sup 16} cm{sup ?3}, resistivity of 66.733–12.758 ? cm, and carrier mobility of 4.964–8.846 cm{sup 2} V{sup ?1} s{sup ?1} at room temperature. However, the film grown at 600 °C showed n-type behavior. Additionally, current-voltage (I–V) characteristic of p-ZnO/n-Si heterojunction showed a diode-like behavior, and that further confirmed the p-type conduction in ZnO by Sb doping. X-ray diffraction measurements showed that all SZO films had (002) preferred crystal orientation. X-ray photoelectron spectroscopy analysis confirmed the formation of Sb{sub Zn}–2V{sub Zn} complex caused acceptor-like behavior in SZO films.

  9. Method and apparatus for simulating atmospheric absorption of solar energy due to water vapor and CO{sub 2}

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-06-20

    A method and apparatus for improving the accuracy of the simulation of sunlight reaching the earth`s surface includes a relatively small heated chamber having an optical inlet and an optical outlet, the chamber having a cavity that can be filled with a heated stream of CO{sub 2} and water vapor. A simulated beam comprising infrared and near infrared light can be directed through the chamber cavity containing the CO{sub 2} and water vapor, whereby the spectral characteristics of the beam are altered so that the output beam from the chamber contains wavelength bands that accurately replicate atmospheric absorption of solar energy due to atmospheric CO{sub 2} and moisture. 8 figs.

  10. The coupling of winds, aerosols and chemistry in Titan's atmosphere

    E-Print Network [OSTI]

    Hourdin, Chez Frédéric

    REVIEW The coupling of winds, aerosols and chemistry in Titan's atmosphere BY SEBASTIEN LEBONNOIS 1'Ae´ronomie, IPSL, CNRS, BP3, 91371 Verrie`res le Buisson, France The atmosphere of Titan is a complex system, where the observed atmospheric structure of Titan's lower atmosphere (mainly in the stratosphere and troposphere

  11. Phase of atmospheric secondary organic material affects its reactivity

    E-Print Network [OSTI]

    of the reactivity of atmospheric SOM particles. atmospheric chemistry chemical aging organic aerosol collectionPhase of atmospheric secondary organic material affects its reactivity Mikinori Kuwata and Scot T of atmospheric organic particles among solid, semisolid, and liquid phases is of keen current scientific interest

  12. ATM401, ATM601, CHEM601 Introduction to Atmospheric Sciences

    E-Print Network [OSTI]

    Moelders, Nicole

    as atmospheric chemistry. You should be able to read and analyze weather maps or climate diagrams, interpret as atmospheric chemistry. Fundamental goals are that you develop skills to think as an atmospheric scientistATM401, ATM601, CHEM601 Introduction to Atmospheric Sciences Fall 2013 Class time: TR 11:30am

  13. Simulation and Theory of Ions at Atmospherically Relevant

    E-Print Network [OSTI]

    Levin, Yan

    Simulation and Theory of Ions at Atmospherically Relevant Aqueous Liquid-Air Interfaces Douglas J in the atmosphere influences air quality and climate. Molecular dy- namics simulations are becoming increasingly in the atmosphere. Here we review simulation studies of atmospherically relevant aqueous liquid-air interfaces

  14. Atmospheric Modelling for Neptune's Methane D/H Ratio - Preliminary Results

    E-Print Network [OSTI]

    Cotton, Daniel V; Bott, Kimberly; Bailey, Jeremy

    2015-01-01

    The ratio of deuterium to hydrogen (D/H ratio) of Solar System bodies is an important clue to their formation histories. Here we fit a Neptunian atmospheric model to Gemini Near Infrared Spectrograph (GNIRS) high spectral resolution observations and determine the D/H ratio in methane absorption in the infrared H-band ($\\sim$ 1.6 {\\mu}m). The model was derived using our radiative transfer software VSTAR (Versatile Software for the Transfer of Atmospheric Radiation) and atmospheric fitting software ATMOF (ATMOspheric Fitting). The methane line list used for this work has only become available in the last few years, enabling a refinement of earlier estimates. We identify a bright region on the planetary disc and find it to correspond to an optically thick lower cloud. Our preliminary determination of CH$_{\\rm 3}$D/CH$_{\\rm 4}$ is 3.0$\\times10^{-4}$, which is in line with the recent determination of Irwin et al. (2014) of 3.0$^{+1.0}_{-0.9}\\sim\\times10^{-4}$, made using the same model parameters and line list but...

  15. Ellerman bombs—evidence for magnetic reconnection in the lower solar atmosphere

    SciTech Connect (OSTI)

    Nelson, C. J.; Doyle, J. G.; Madjarska, M. S. [Armagh Observatory, College Hill, Armagh BT61 9DG (United Kingdom); Shelyag, S. [Monash Centre for Astrophysics, School of Mathematical Sciences, Monash University, Clayton, VIC 3800 (Australia); Mathioudakis, M. [Astrophysical Research Centre, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom); Uitenbroek, H. [National Solar Observatory, Sacramento Peak, P.O. Box 62, Sunpsot, NM 88349 (United States); Erdélyi, R. [Solar Physics and Space Plasma Research Centre, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2013-12-20

    The presence of photospheric magnetic reconnection has long been thought to give rise to short and impulsive events, such as Ellerman bombs (EBs) and Type II spicules. In this article, we combine high-resolution, high-cadence observations from the Interferometric BIdimensional Spectrometer and Rapid Oscillations in the Solar Atmosphere instruments at the Dunn Solar Telescope, National Solar Observatory, New Mexico, with co-aligned Solar Dynamics Observatory Atmospheric Imaging Assembly and Hinode Solar Optical Telescope (SOT) data to observe small-scale events situated within an active region. These data are then compared with state-of-the-art numerical simulations of the lower atmosphere made using the MURaM code. It is found that brightenings, in both the observations and the simulations, of the wings of the H? line profile, interpreted as EBs, are often spatially correlated with increases in the intensity of the Fe I ?6302.5 line core. Bipolar regions inferred from Hinode/SOT magnetic field data show evidence of flux cancellation associated, co-spatially, with these EBs, suggesting that magnetic reconnection could be a driver of these high-energy events. Through the analysis of similar events in the simulated lower atmosphere, we are able to infer that line profiles analogous to the observations occur co-spatially with regions of strong opposite-polarity magnetic flux. These observed events and their simulated counterparts are interpreted as evidence of photospheric magnetic reconnection at scales observable using current observational instrumentation.

  16. The Atmospheric Monitoring System of the JEM-EUSO Space Mission

    E-Print Network [OSTI]

    Frias, M D Rodriguez; Bozzo, E; del Peral, L; Neronov, A; Wada, S

    2015-01-01

    An Atmospheric Monitoring System (AMS) is a mandatory and key device of a space-based mission which aims to detect Ultra-High Energy Cosmic Rays (UHECR) and Extremely-High Energy Cosmic Rays (EHECR) from Space. JEM-EUSO has a dedicated atmospheric monitoring system that plays a fundamental role in our understanding of the atmospheric conditions in the Field of View (FoV) of the telescope. Our AMS consists of a very challenging space infrared camera and a LIDAR device, that are being fully designed with space qualification to fulfil the scientific requirements of this space mission. The AMS will provide information of the cloud cover in the FoV of JEM-EUSO, as well as measurements of the cloud top altitudes with an accuracy of 500 m and the optical depth profile of the atmosphere transmittance in the direction of each air shower with an accuracy of 0.15 degree and a resolution of 500 m. This will ensure that the energy of the primary UHECR and the depth of maximum development of the EAS ( Extensive Air Shower)...

  17. Atmospheric effects on Quaternary polarization encoding for free space communication, laboratory simulation

    E-Print Network [OSTI]

    Soorat, Ram

    2015-01-01

    We have simulated atmospheric effects such as fog and smoke in laboratory environment to simulate depolarisation due to atmospheric effects during a free space optical communi- cation. This has been used to study noise in two components of quaternary encoding for polarization shift keying. Individual components of a Quaternary encoding, such as vertical and horizontal as well as 45$^\\circ$ and 135$^\\circ$ , are tested separately and indicates that the depo- larization effects are different for these two situation. However, due to a differential method used to extract information bits, the protocol shows extremely low bit error rates. The information obtained is useful during deployment of a fully functional Quaternary encoded PolSK scheme in free space.

  18. Atmospheric-pressure air microplasma jets in aqueous media for the inactivation of Pseudomonas fluorescens cells

    SciTech Connect (OSTI)

    Zhang, Xianhui; Yang, Si-ze [Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005 (China)] [Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Liu, Dongping [Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005 (China) [Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); Song, Ying [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China) [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); Sun, Yue [School of Physics, Changchun University of Science and Technology, Changchun 130022 (China)] [School of Physics, Changchun University of Science and Technology, Changchun 130022 (China)

    2013-05-15

    The hollow fiber-based cold air microplasma jet array running at atmospheric pressure has been designed to inactivate Pseudomonas fluorescens (P. fluorescens) cells in vitro in aqueous media. The influences of electrode configurations, air flow rate, and applied voltage on the discharge characteristics of the single microplasma jet operating in aqueous media are presented, and the bactericidal efficiency of the hollow fibers-based and large-volume microplasma jet array is reported. Optical emission spectroscopy is utilized to identify excited species during the antibacterial testing of plasma in solutions. These well-aligned and rather stable air microplasma jets containing a variety of short-lived species, such as OH and O radicals and charged particles, are in direct contact with aqueous media and are very effective in killing P. fluorescens cells in aqueous media. This design shows its potential application for atmospheric pressure air plasma inactivation of bacteria cells in aqueous media.

  19. Optical apparatus for forming correlation spectrometers and optical processors

    DOE Patents [OSTI]

    Butler, M.A.; Ricco, A.J.; Sinclair, M.B.; Senturia, S.D.

    1999-05-18

    Optical apparatus is disclosed for forming correlation spectrometers and optical processors. The optical apparatus comprises one or more diffractive optical elements formed on a substrate for receiving light from a source and processing the incident light. The optical apparatus includes an addressing element for alternately addressing each diffractive optical element thereof to produce for one unit of time a first correlation with the incident light, and to produce for a different unit of time a second correlation with the incident light that is different from the first correlation. In preferred embodiments of the invention, the optical apparatus is in the form of a correlation spectrometer; and in other embodiments, the apparatus is in the form of an optical processor. In some embodiments, the optical apparatus comprises a plurality of diffractive optical elements on a common substrate for forming first and second gratings that alternately intercept the incident light for different units of time. In other embodiments, the optical apparatus includes an electrically-programmable diffraction grating that may be alternately switched between a plurality of grating states thereof for processing the incident light. The optical apparatus may be formed, at least in part, by a micromachining process. 24 figs.

  20. Fiber optic compass development 

    E-Print Network [OSTI]

    Park, Kyongtae

    2005-11-01

    magnetometer based on this principle, a single mode optical fiber coated with nickel [6] 3 or wrapped around a Metglas cylinder [7] experiences a strain which is dependent on the external magnetic field [8-10]. The fiber is deployed in one arm of a Michelson...

  1. Optical cloaking with metamaterials

    E-Print Network [OSTI]

    F. Bilotti; S. Tricarico; L. Vegni

    2008-06-06

    In this contribution, we present the design of cylindrical electromagnetic cloaks working at optical frequencies, making use of layered structures of plasmonic and non-plasmonic materials. The simulated results confirm the validity of the proposed approach and show a rather broad-band behavior of the cloaking device.

  2. High throughput optical scanner

    DOE Patents [OSTI]

    Basiji, David A. (Seattle, WA); van den Engh, Gerrit J. (Seattle, WA)

    2001-01-01

    A scanning apparatus is provided to obtain automated, rapid and sensitive scanning of substrate fluorescence, optical density or phosphorescence. The scanner uses a constant path length optical train, which enables the combination of a moving beam for high speed scanning with phase-sensitive detection for noise reduction, comprising a light source, a scanning mirror to receive light from the light source and sweep it across a steering mirror, a steering mirror to receive light from the scanning mirror and reflect it to the substrate, whereby it is swept across the substrate along a scan arc, and a photodetector to receive emitted or scattered light from the substrate, wherein the optical path length from the light source to the photodetector is substantially constant throughout the sweep across the substrate. The optical train can further include a waveguide or mirror to collect emitted or scattered light from the substrate and direct it to the photodetector. For phase-sensitive detection the light source is intensity modulated and the detector is connected to phase-sensitive detection electronics. A scanner using a substrate translator is also provided. For two dimensional imaging the substrate is translated in one dimension while the scanning mirror scans the beam in a second dimension. For a high throughput scanner, stacks of substrates are loaded onto a conveyor belt from a tray feeder.

  3. Genesis of CREOLGenesis of CREOL The College of Optics & PhotonicsThe College of Optics & Photonics

    E-Print Network [OSTI]

    Van Stryland, Eric

    Genesis of CREOLGenesis of CREOL The College of Optics & PhotonicsThe College of Optics & Photonics, the School of OpticsCREOL, the School of Optics CREOL, The College of Optics & PhotonicsCREOL, The College of Optics & Photonics CREOL & FPCE, The College of Optics and PhotonicsCREOL & FPCE, The College of Optics

  4. Bachelor of Science Degree in Optics Bachelor of Science Degree in Optical Engineering

    E-Print Network [OSTI]

    Cantlon, Jessica F.

    Bachelor of Science Degree in Optics Bachelor of Science Degree in Optical Engineering The Institute of Optics Major Requirements OPT 201 Geometrical Optics Lab (2 cr.) OPT 202 Physical Optics Lab (2 Theory of Optics OPT 225 Optical Sources and Detectors OPT 241 Geometrical Optics OPT 242 Aberrations

  5. Bachelor of Science Degree in Optics Bachelor of Science Degree in Optical Engineering

    E-Print Network [OSTI]

    Mahon, Bradford Z.

    Bachelor of Science Degree in Optics Bachelor of Science Degree in Optical Engineering The Institute of Optics Major Requirements OPT 197 Geometrical Optics Lab (2 cr.) OPT 198 Physical Optics Lab (2 Theory of Optics OPT 225 Optical Sources and Detectors OPT 241 Geometrical Optics OPT 242 Aberrations

  6. Optical single sideband modulation using strong optical injection-locked semiconductor lasers

    E-Print Network [OSTI]

    Sung, Hyuk-Kee; Lau, Erwin K.; Wu, Ming C.

    2007-01-01

    generation by direct modulation of optical injection-lockedreported direct SSB modulation from an optically injection-

  7. 4-ID-D optics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4-ID-D Beamline Optics A schetch of the major optical components for beam line 4-ID-D are shown above. All these components located in the B-station upstream from the D...

  8. Frame dragging with optical vortices 

    E-Print Network [OSTI]

    Strohaber, James

    2011-12-22

    General Relativistic calculations in the linear regime have been made for electromagnetic beams of radiation known as optical vortices. These exotic beams of light carry a physical quantity known as optical orbital angular momentum (OAM...

  9. Diagnostics Implemented on NIF - Optical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Streaked Optical Pyrometer Shared LOS 90-315 DIM LLNL SOP measures the breakout time of an optically emitting shock. Robert M. Malone et al., "Combining a thermal-imaging...

  10. Optics (XSD) | Advanced Photon Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Optics Group (X-ray Science Division) The mission of the Optics Group is to facilitate the efficient and productive use and operation of APS beamline-based research facilities. In...

  11. Distributed optical fiber vibration sensing 

    E-Print Network [OSTI]

    Yu, Hui

    2001-01-01

    This thesis presents a distributed optical fiber vibration sensor. The purpose of this sensing system is to monitor, in real time, the status of railcars by burying an optical fiber underground beside the rails. Using a coherent homodyne technique...

  12. Atmospheric Pressure Plasma Process And Applications

    SciTech Connect (OSTI)

    Peter C. Kong; Myrtle

    2006-09-01

    This paper provides a general discussion of atmospheric-pressure plasma generation, processes, and applications. There are two distinct categories of atmospheric-pressure plasmas: thermal and nonthermal. Thermal atmospheric-pressure plasmas include those produced in high intensity arcs, plasma torches, or in high intensity, high frequency discharges. Although nonthermal plasmas are at room temperatures, they are extremely effective in producing activated species, e.g., free radicals and excited state atoms. Thus, both thermal and nonthermal atmosphericpressure plasmas are finding applications in a wide variety of industrial processes, e.g. waste destruction, material recovery, extractive metallurgy, powder synthesis, and energy conversion. A brief discussion of recent plasma technology research and development activities at the Idaho National Laboratory is included.

  13. A Community Atmosphere Model with Superparameterized Clouds

    SciTech Connect (OSTI)

    Randall, David; Branson, Mark; Wang, Minghuai; Ghan, Steven J.; Craig, Cheryl; Gettelman, A.; Edwards, Jim

    2013-06-18

    In 1999, National Center for Atmospheric Research (NCAR) scientists Wojciech Grabowski and Piotr Smolarkiewicz created a "multiscale" atmospheric model in which the physical processes associated with clouds were represented by running a simple high-resolution model within each grid column of a lowresolution global model. In idealized experiments, they found that the multiscale model produced promising simulations of organized tropical convection, which other models had struggled to produce. Inspired by their results, Colorado State University (CSU) scientists Marat Khairoutdinov and David Randall created a multiscale version of the Community Atmosphere Model (CAM). They removed the cloud parameterizations of the CAM, and replaced them with Khairoutdinov's high-resolution cloud model. They dubbed the embedded cloud model a "super-parameterization," and the modified CAM is now called the "SP-CAM." Over the next several years, many scientists, from many institutions, have explored the ability of the SP-CAM to simulate tropical weather systems, the day-night changes of precipitation, the Asian and African monsoons, and a number of other climate processes. Cristiana Stan of the Center for Ocean-Land-Atmosphere Interactions found that the SP-CAM gives improved results when coupled to an ocean model, and follow-on studies have explored the SP-CAM's utility when used as the atmospheric component of the Community Earth System Model. Much of this research has been performed under the auspices of the Center for Multiscale Modeling of Atmospheric Processes, a National Science Foundation (NSF) Science and Technology Center for which the lead institution is CSU.

  14. Optics learning through affordable kit

    SciTech Connect (OSTI)

    P, Anusha N, E-mail: anushnp@gmail.com, E-mail: chitrashaji@gmail.com, E-mail: aloksharan@gmail.com; Shaji, Chitra, E-mail: anushnp@gmail.com, E-mail: chitrashaji@gmail.com, E-mail: aloksharan@gmail.com; Sharan, Alok, E-mail: anushnp@gmail.com, E-mail: chitrashaji@gmail.com, E-mail: aloksharan@gmail.com [Department of Physics, Pondicherry University, Puducherry-605014 (India)

    2014-10-15

    An affordable kit which helps to understand some of the optical phenomena qualitatively and quantitatively is presented in this paper. It supplements optics taught in classes. The kit consists of equipments which are available in the market at nominal cost such as laser pointer, lenses, glass plates, razor blades, coins, ball bearing etc. Experiments which come under wave optics (interference and diffraction) and ray optics (reflection and refraction) are explained using this kit.

  15. Ultrafast Optics and Optical Fiber Communications Laboratory http://purcell.ecn.purdue.edu/~fsoptics/

    E-Print Network [OSTI]

    Purdue University

    Ultrafast Optics and Optical Fiber Communications Laboratory http, A. M. Weiner Purdue University C. Lin Avanex Corporation Conference on Lasers and Electro Optics;Ultrafast Optics and Optical Fiber Communications Laboratory http://purcell.ecn.purdue.edu/~fsoptics/ 2

  16. Catalog Entry for PHYS 522: NONLINEAR OPTICS PHYS 522 (3) Nonlinear Optics (3)

    E-Print Network [OSTI]

    Akerib, Daniel S.

    Catalog Entry for PHYS 522: NONLINEAR OPTICS PHYS 522 (3) Nonlinear Optics (3) Classical and propagation. Properties of optical fibers and nonlinear materials. Theory of nonlinear propagation, solitons, inverse scattering transforms, optical chaos. Applications to lasers, optical violability, self

  17. Controlled atmosphere for fabrication of cermet electrodes

    DOE Patents [OSTI]

    Ray, Siba P. (Murrysville, PA); Woods, Robert W. (New Kensington, PA)

    1998-01-01

    A process for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750.degree. C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5-3000 ppm in order to obtain a desired composition in the resulting composite.

  18. Controlled atmosphere for fabrication of cermet electrodes

    DOE Patents [OSTI]

    Ray, S.P.; Woods, R.W.

    1998-08-11

    A process is disclosed for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750 C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5--3000 ppm in order to obtain a desired composition in the resulting composite. 2 figs.

  19. A field study on the trace metal behavior in atmospheric circulating fluidized-bed coal combustion

    SciTech Connect (OSTI)

    Lind, T.; Kauppinen, E.I.; Jokiniemi, J.K.; Maenhaut, W.

    1994-12-31

    Trace element behavior in atmospheric circulating fluidized-bed combustion (CFBC) of Venezuelan bituminous coal was studied by determining particle size distributions in the CFBC flue gas. The size distributions of calcium, iron, aluminium, and 21 trace elements, Sc, V, Cr, Mn, Co, Ni, Zn, Ga, As, Se, Sr, Cd, Sb, Cs, Ba, La, Ce, Sm, Lu, Pb, and Th, in the size range 0.01--70{micro}m, were determined by collecting aerosols with a low-pressure impactor-cyclone sampling train from the flue gases of an 80-MW(th) CFBC boiler upstream of the electrostatic precipitator. The collected samples were analyzed gravimetrically and with instrumental neutron activation analysis (INAA), particle-induced X-ray emission analysis (PIXE), and inductively coupled plasma mass spectrometry (ICP-MS). The number size distributions of the aerosols were determined with a differential electrical mobility method in the size range 0.01--0.8 {micro}m. In the ultrafine particle mode, i.e., D{sub p} < 0.1 {micro}m, the CFBC number concentrations varied strongly during the experiments, being one to two orders of magnitude lower than those observed in pulverized coal combustion. For all of the elements studied, 75% or more were found in particles larger than 5{micro}m. None of the studied elements showed significant vaporization and subsequent chemical surface reaction or condensation in the CFBC. The Sr, Se, V, Zn, Ga, Cs, Ba, La, Sm, Lu, and Th size distributions resembled those of aluminium, suggesting their occurrence in aluminosilicate-rich particles in the fly ash. The association of the trace elements with aluminium in the fly ash particles may result from reactions of the trace elements with the aluminosilicate mineral particles inside the burning coal particles, or their initial occurrence in association with these minerals.

  20. Large core fiber optic cleaver

    DOE Patents [OSTI]

    Halpin, J.M.

    1996-03-26

    The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 {micro}m. 30 figs.