Powered by Deep Web Technologies
Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Sample heating in near-field scanning optical microscopy  

E-Print Network [OSTI]

Heating near the aperture of aluminumcoated,fiber opticnear-field scanning optical microscopy probes was studied as a function of input and output powers. Using the shear-force feedback method, near-field probes were positioned nanometers above a...

Erickson, Elizabeth S.; Dunn, Robert C.

2005-10-05T23:59:59.000Z

2

Widely tuneable scattering-type scanning near-field optical microscopy using pulsed quantum cascade lasers  

SciTech Connect (OSTI)

We demonstrate the use of a pulsed quantum cascade laser, wavelength tuneable between 6 and 10??m, with a scattering-type scanning near-field optical microscope (s-SNOM). A simple method for calculating the signal-to-noise ratio (SNR) of the s-SNOM measurement is presented. For pulsed lasers, the SNR is shown to be highly dependent on the degree of synchronization between the laser pulse and the sampling circuitry; in measurements on a gold sample, the SNR is 26 with good synchronization and less than 1 without. Simulations and experimental s-SNOM images, with a resolution of 100?nm, corresponding to ?/80, and an acquisition time of less than 90 s, are presented as proof of concept. They show the change in the field profile of plasmon-resonant broadband antennas when they are excited with wavelengths of 7.9 and 9.5??m.

Yoxall, Edward, E-mail: edward.yoxall@imperial.ac.uk; Rahmani, Mohsen; Maier, Stefan A.; Phillips, Chris C. [The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2AZ (United Kingdom)] [The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2AZ (United Kingdom); Navarro-Cía, Miguel [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2BT (United Kingdom)] [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2BT (United Kingdom)

2013-11-18T23:59:59.000Z

3

Imaging of quantum Hall edge states under quasiresonant excitation by a near-field scanning optical microscope  

SciTech Connect (OSTI)

A high resolution mapping of quantum Hall edge states has been performed by locally creating electrons with small excess energies with a near-field scanning optical microscope in a dilution refrigerator. We have observed fine structures parallel to the edge in photovoltage signals, which appear only at low temperature. The observed fine structures near sample edges have been seen to shift inward with increase in magnetic field in accordance with Chklovskii Shklovskii, and Glazman model.

Ito, H.; Shibata, Y.; Mamyoda, S.; Ootuka, Y.; Nomura, S. [Division of Physics, University of Tsukuba, Tennodai, Tsukuba, 305-8571 (Japan); Kashiwaya, S. [National Institute of Advanced Industrial Science and Technology (AIST), Umezono, Tsukuba, 305-8568 (Japan); Yamaguchi, M.; Akazaki, T.; Tamura, H. [NTT Basic Research Laboratories, NTT Corporation, Morinosato-Wakamiya, Atsugi, 243-0198 (Japan)

2013-12-04T23:59:59.000Z

4

Single Defect Center Scanning Near-Field Optical Microscopy on Graphene  

E-Print Network [OSTI]

We demonstrate high resolution scanning fluorescence resonance energy transfer 10 microscopy between a single nitrogen-vacancy center as donor and graphene as acceptor. 11 Images with few nanometer resolution of single and multilayer graphene structures were 12 attained. An energy transfer efficiency of 30% at distances of 10nm between a single 13 defect and graphene was measured. Further the energy transfer distance dependence of 14 the nitrogen-vacancy center to graphene was measured to show the predicted d-4 15 dependence. Our studies pave the way towards a diamond defect center based versatile 16 single emitter scanning microscope.

J. Tisler; T. Oeckinghaus; R. Stöhr; R. Kolesov; F. Reinhard; J. Wrachtrup

2013-01-02T23:59:59.000Z

5

Probing nanoscale photo-oxidation in organic films using spatial hole burning near-field scanning optical microscopy  

E-Print Network [OSTI]

Probing nanoscale photo-oxidation in organic films using spatial hole burning near-field scanning from a stationary NSOM tip to induce photo-oxidation. The reduction in the fluorescence yield resulting photo-oxidation as a function of time, position, and environment free from the limits of far

Buratto, Steve

6

Scanning tip microwave near field microscope  

DOE Patents [OSTI]

A microwave near field microscope has a novel microwave probe structure wherein the probing field of evanescent radiation is emitted from a sharpened metal tip instead of an aperture or gap. This sharpened tip, which is electrically and mechanically connected to a central electrode, extends through and beyond an aperture in an endwall of a microwave resonating device such as a microwave cavity resonator or a microwave stripline resonator. Since the field intensity at the tip increases as the tip sharpens, the total energy which is radiated from the tip and absorbed by the sample increases as the tip sharpens. The result is improved spatial resolution without sacrificing sensitivity.

Xiang, Xiao-Dong (Alameda, CA); Schultz, Peter G. (Oakland, CA); Wei, Tao (Albany, CA)

1998-01-01T23:59:59.000Z

7

Infrared Scattering Scanning Near-Field Optical Microscopy Using An External Cavity Quantum Cascade Laser For Nanoscale Chemical Imaging And Spectroscopy of Explosive Residues  

SciTech Connect (OSTI)

Infrared scattering scanning near-field optical microscopy (s-SNOM) is an apertureless superfocusing technique that uses the antenna properties of a conducting atomic force microscope (AFM) tip to achieve infrared spatial resolution below the diffraction limit. The instrument can be used either in imaging mode, where a fixed wavelength light source is tuned to a molecular resonance and the AFM raster scans an image, or in spectroscopy mode where the AFM is held stationary over a feature of interest and the light frequency is varied to obtain a spectrum. In either case, a strong, stable, coherent infrared source is required. Here we demonstrate the integration of a broadly tunable external cavity quantum cascade laser (ECQCL) into an s-SNOM and use it to obtain infrared spectra of microcrystals of chemicals adsorbed onto gold substrates. Residues of the explosive compound tetryl was deposited onto gold substrates. s-SNOM experiments were performed in the 1260-1400 cm?1 tuning range of the ECQCL, corresponding to the NO2 symmetric stretch vibrational fingerprint region. Vibrational infrared spectra were collected on individual chemical domains with a collection area of *500nm2 and compared to ensemble averaged far-field reflection-absorption infrared spectroscopy (RAIRS) results.

Craig, Ian M.; Phillips, Mark C.; Taubman, Matthew S.; Josberger, Erik E.; Raschke, Markus Bernd

2013-02-04T23:59:59.000Z

8

Surface Plasmon mediated near-field imaging and optical addressing in nanoscience  

E-Print Network [OSTI]

We present an overview of recent progress in plasmonics. We focus our study on the observation and excitation of surface plasmon polaritons (SPPs) with optical near-field microscopy. We discuss in particular recent applications of photon scanning tunnelling microscope (PSTM) for imaging of SPP propagating in metal and dielectric wave guides. We show how near-field scanning optical microscopy (NSOM) can be used to optically and actively address remotely nano-objects such as quantum dots. Additionally we compare results obtained with near-field microscopy to those obtained with other optical far-field methods of analysis such as leakage radiation microscopy (LRM).

Drezet, A; Krenn, J R; Brun, M; Huant, S

2007-01-01T23:59:59.000Z

9

Near-Field Magneto-Optical Microscope  

DOE Patents [OSTI]

A device and method for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample is disclosed. A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof in communication with a fiber optic for transferring incoming linearly polarized light from a source thereof to the particle and for transferring reflected light from the particle is provided. The fiber optic has a reflective material trapping light within the fiber optic and in communication with a light detector for determining the polarization of light reflected from the particle as a function of the strength and direction of the magnetic field of the sample. Linearly polarized light from the source thereof transferred to the particle positioned proximate the sample is affected by the magnetic field of the sample sensed by the particle such that the difference in polarization of light entering and leaving the particle is due to the magnetic field of the sample. Relative movement between the particle and sample enables mapping.

Vlasko-Vlasov, Vitalii; Welp, Ulrich; and Crabtree, George W.

2005-12-06T23:59:59.000Z

10

Near Field Magneto-Optical Microscope  

DOE Patents [OSTI]

A device and method for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample is disclosed. A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof in communication with a fiber optic for transferring incoming linearly polarized light from a source thereof to the particle and for transferring reflected light from the particle is provided. The fiber optic has a reflective material trapping light within the fiber optic and in communication with a light detector for determining the polarization of light reflected from the particle as a function of the strength and direction of the magnetic field of the sample. Linearly polarized light from the source thereof transferred to the particle positioned proximate the sample is affected by the magnetic field of the sample sensed by the particle such that the difference in polarization of light entering and leaving the particle is due to the magnetic field of the sample. Relative movement between the particle and sample enables mapping.

Vlasko-Vlasov, Vitalii K. (Downers Grove, IL); Welp, Ulrich (Lisle, IL); Crabtree, George W. (Chicago, IL)

2005-12-06T23:59:59.000Z

11

A near-field scanning microwave microscope based on a superconducting resonator for low power measurements  

E-Print Network [OSTI]

We report on the design and performance of a cryogenic (300 mK) near-field scanning microwave microscope. It uses a microwave resonator as the near-field sensor, operating at a frequency of 6 GHz and microwave probing amplitudes down to 100 uV, approaching low enough photon population (N~1000) of the resonator such that coherent quantum manipulation becomes feasible. The resonator is made out of a miniaturized distributed fractal superconducting circuit that is integrated with the probing tip, micromachined to be compact enough such that it can be mounted directly on a quartz tuning-fork, and used for parallel operation as an atomic force microscope (AFM). The resonator is magnetically coupled to a transmission line for readout, and to achieve enhanced sensitivity we employ a Pound-Drever-Hall measurement scheme to lock to the resonance frequency. We achieve a well localized near-field around the tip such that the microwave resolution is comparable to the AFM resolution, and a capacitive sensitivity down to 6.4x10^-20 F/rtHz, limited by mechanical noise. We believe that the results presented here are a significant step towards probing quantum systems at the nanoscale using near-field scanning microwave microscopy.

S. E. de Graaf; A. V. Danilov; A. Adamyan; S. E. Kubatkin

2014-04-02T23:59:59.000Z

12

Near-field microscopy with a scanning nitrogen-vacancy color center in a diamond nanocrystal: A brief review  

E-Print Network [OSTI]

We review our recent developments of near-field scanning optical microscopy (NSOM) that uses an active tip made of a single fluorescent nanodiamond (ND) grafted onto the apex of a substrate fiber tip. The ND hosting a limited number of nitrogen-vacancy (NV) color centers, such a tip is a scanning quantum source of light. The method for preparing the ND-based tips and their basic properties are summarized. Then we discuss theoretically the concept of spatial resolution that is achievable in this special NSOM configuration and find it to be only limited by the scan height over the imaged system, in contrast with the standard aperture-tip NSOM whose resolution depends critically on both the scan height and aperture diameter. Finally, we describe a scheme we have introduced recently for high-resolution imaging of nanoplasmonic structures with ND-based tips that is capable of approaching the ultimate resolution anticipated by theory.

Drezet, A; Cuche, A; Mollet, O; Berthel, M; Huant, S

2015-01-01T23:59:59.000Z

13

A near-field scanning microwave microscope based on a superconducting resonator for low power measurements  

E-Print Network [OSTI]

We report on the design and performance of a cryogenic (300 mK) near-field scanning microwave microscope. It uses a microwave resonator as the near-field sensor, operating at a frequency of 6 GHz and microwave probing amplitudes down to 100 uV, approaching low enough photon population (N~1000) of the resonator such that coherent quantum manipulation becomes feasible. The resonator is made out of a miniaturized distributed fractal superconducting circuit that is integrated with the probing tip, micromachined to be compact enough such that it can be mounted directly on a quartz tuning-fork, and used for parallel operation as an atomic force microscope (AFM). The resonator is magnetically coupled to a transmission line for readout, and to achieve enhanced sensitivity we employ a Pound-Drever-Hall measurement scheme to lock to the resonance frequency. We achieve a well localized near-field around the tip such that the microwave resolution is comparable to the AFM resolution, and a capacitive sensitivity down to 6...

de Graaf, S E; Adamyan, A; Kubatkin, S E

2014-01-01T23:59:59.000Z

14

Nonlinear optical tuning of photonic crystal microcavities by near-field probe  

SciTech Connect (OSTI)

We report on a nonlinear way to control and tune the dielectric environment of photonic crystal microcavities exploiting the local heating induced by near-field laser excitation at different excitation powers. The temperature gradient due to the optical absorption results in an index of refraction gradient which modifies the dielectric surroundings of the cavity and shifts the optical modes. Reversible tuning can be obtained either by changing the excitation power density or by exciting in different points of the photonic crystal microcavity.

Vignolini, Silvia; Zani, Margherita; Riboli, Francesco; Vinattieri, Anna; Wiersma, Diederik S.; Gurioli, Massimo [LENS and Department of Physics, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); Intonti, Francesca [LENS and Department of Physics, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); CNISM, Unita di Ricerca di Firenze, Via Sansone 1, 50019 Sesto Fiorentino (Italy); Balet, Laurent; Li, Lianhe [Ecole Polytechnique Federale de Lausanne, Institute of Photonics and Quantum Electronics, Station 3, CH-1015 Lausanne (Switzerland); Colocci, Marcello [CNISM, Unita di Ricerca di Firenze, Via Sansone 1, 50019 Sesto Fiorentino (Italy); Francardi, Marco; Gerardino, Annamaria [Institute of Photonics and Nanotechnology, CNR, via del Cineto Romano 42, 00156 Roma (Italy); Fiore, Andrea [COBRA Research Institute, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands)

2008-07-14T23:59:59.000Z

15

Fluorescence resonance energy transfer scanning near-field optical microscopy  

Science Journals Connector (OSTI)

...and applications. New York: Wiley Interscience...Fluorescence resonance energy transfer SNOM 919...fluorescence resonance energy transfer source...Electromagnetic theory. New York: McGraw-Hill...hierarchy and directed energy transfer in conjugated...

2004-01-01T23:59:59.000Z

16

A gap capacitance method for slider flying height measurement in near-field optical disk drives  

Science Journals Connector (OSTI)

In order to overcome the diffraction limit of conventional optical disk drives, and substantially increase data storage capacity and density, near-field optical disk drives remain to be realized. The slider of a flying pickup head in a near-field optical disk drive has to fly at a stable spacing above the disk surface. To sense the slider flying height, a gap capacitance method is developed in this study to measure capacitance variation between the pickup head and disk surface. The capacitance varying with the flying height is modulated by a Colpitts oscillator. Subsequent demodulation accounts for height variation of the flying pickup head. Measurement results of this method are verified by using a laser Doppler interferometer.

J.W. Chen; T.S. Liu

2004-01-01T23:59:59.000Z

17

Direct Observation of Optically Forbidden Energy Transfer between CuCl Quantum Cubes via Near-Field Optical Spectroscopy  

Science Journals Connector (OSTI)

We report, for the first time, evidence of near-field energy transfer among CuCl quantum cubes using an ultrahigh-resolution near-field optical microscopy and spectroscopy in the near UV region at 15 K. The sample was high-density CuCl quantum cubes embedded in a NaCl matrix. Measured spatial distributions of the luminescence intensities from 4.6-nm and 6.3-nm quantum cubes clearly established anticorrelation features. This is thought to be a manifestation of the energy transfer from the lowest state of exciton in 4.6-nm quantum cubes to the first dipole-forbidden excited state of exciton in 6.3-nm quantum cubes, which is attributed to the resonant optical near-field interaction.

Tadashi Kawazoe; Kiyoshi Kobayashi; Jungshik Lim; Yoshihito Narita; Motoichi Ohtsu

2002-01-25T23:59:59.000Z

18

Piezoelectric & Optical Set-up to measure an Electrical Field. Application to the Longitudinal Near-Field generated by a  

E-Print Network [OSTI]

influences the longitudinal electrical near-field generated by it. For this application, we designed our set extremity on the longitudinal electrical near-field generated by a coaxial cable. Considering1/12 Piezoelectric & Optical Set-up to measure an Electrical Field. Application to the Longitudinal

Paris-Sud XI, Université de

19

Head–disk interface problems in first-surface near-field optical recording with flying optical head  

Science Journals Connector (OSTI)

Near-field recording (NFR) technology using a flying optical head is applied for high density optical data storage. Diamond-like carbon (DLC) film and PFPE lubricant film are coated on utmost NFR disk to reduce the tribological problems. A contamination at the head–disk interface (HDI), especially on a solid immersion lens (SIL) is observed. The contaminants are composed of dust materials from the surroundings and lubricant materials from a disk surface. The contaminants are supposed to be condensed by heat from a writing laser beam at the HDI. To avoid the contamination problem, a cover-layer is coated and a focal plane moved under the cover-layer from the HDI. First-surface near-field recording configuration can be modified by laminating a cover-layer, which enhances the possibility of a practical application with a media removability function.

Jin-Hong Kim

2008-01-01T23:59:59.000Z

20

Modeling and characterization of a cantilever-based near-field scanning microwave impedance microscope  

Science Journals Connector (OSTI)

This paper presents a detailed modeling and characterization of a microfabricated cantilever-based scanning microwave probe with separated excitation and sensing electrodes. Using finite-element analysis we model the tip-sample interaction as small impedance changes between the tip electrode and the ground at our working frequencies near 1 GHz . The equivalent lumped elements of the cantilever can be determined by transmission line simulation of the matching network which routes the cantilever signals to 50 ? feed lines. In the microwave electronics the background common-mode signal is canceled before the amplifier stage so that high sensitivity (below 1 aF capacitance changes) is obtained. Experimental characterization of the microwavemicroscope was performed on ion-implanted Si wafers and patterned semiconductor samples. Pure electrical or topographical signals can be obtained from different reflection modes of the probe.

K. Lai; W. Kundhikanjana; M. Kelly; Z. X. Shen

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Accessing the Optical Magnetic Near-Field through Babinet’s Principle  

Science Journals Connector (OSTI)

For illumination and collection two Schwarzschild type objectives were used (32 × , NA = 0.65), with nominal incidence angle between 18° and 40° at focus. ... The tip-scattered antenna near-field is collected by the same parabolic mirror in a backscattering geometry and filtered by a vertical polarizer before being directed to a MCT detector, where it is detected interferometrically. Demodulation of the signal at the second or higher harmonic of the tip-dither frequency ?AFM using a lock-in amplifier suppresses the far-field background signal. ...

Honghua U. Yang; Robert L. Olmon; Kseniya S. Deryckx; Xiaoji G. Xu; Hans A. Bechtel; Yuancheng Xu; Brian A. Lail; Markus B. Raschke

2014-08-06T23:59:59.000Z

22

Near-field enhanced optical tweezers utilizing femtosecond-laser nanostructured substrates  

E-Print Network [OSTI]

We present experimental evidence of plasmonic-enhanced optical tweezers, of polystyrene beads in deionized water in the vicinity of metal-coated nanostructures. The optical tweezers operate with a continuous wave (CW) near-infrared laser. We employ a Cu/Au bilayer that significantly improves dissipation of heat generated by the trapping laser beam and avoid de-trapping from heat convection currents. We investigate the improvement of the optical trapping force, the effective trapping quality factor, and observe an exponential distance dependence of the trapping force from the nanostructures, expected from the evanescent plasmon field.

Kotsifaki, Domna G; Lagoudakis, Pavlos G

2015-01-01T23:59:59.000Z

23

Optical scanning apparatus  

DOE Patents [OSTI]

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.

Villarreal, R.A.

1985-11-06T23:59:59.000Z

24

Scanning near-field optical microscopy based on the heterodyne phase-controlled oscillator method  

E-Print Network [OSTI]

obtained for the case of larger vibration amplitudes of the tip. © 2000 American Institute of Physics. S, the particular mechanical properties of such a ``lever'' prevented the broad use of the force-measurement. The idea behind the method is based on the measurement of the damping of the oscillation of the tip subject

Texas at Austin. University of

25

Characterization of power induced heating and damage in fiber optic probes for near-field scanning optical microscopy  

E-Print Network [OSTI]

polymer sample are measured as a function of probe output power, as was previously reported for pulled NSOM probes. The results reveal that sample heating increases rapidly to ?55–60°C as output powers reach ?50nW. At higher output powers, the sample...

Dickenson, Nicholas E.; Erickson, Elizabeth S.; Mooren, Olivia L.; Dunn, Robert C.

2007-04-07T23:59:59.000Z

26

E-Print Network 3.0 - appendix a3 near-field Sample Search Results  

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

Despite the rapid growth of near-field optical microscopy in the past... decade, many questions about the imaging properties of near-field microscopes ... Source: Dainty, Chris...

27

Infrared near-field imaging and spectroscopy based on thermal or synchrotron radiation  

SciTech Connect (OSTI)

We demonstrate the coupling of a scattering near-field scanning optical microscope combined with a Fourier transform infrared spectrometer. The set-up operates using either the near-field thermal emission from the sample itself, which is proportional to the electromagnetic local density of states, or with an external infrared synchrotron source, which is broadband and highly brilliant. We perform imaging and spectroscopy measurements with sub-wavelength spatial resolution in the mid-infrared range on surfaces made of silicon carbide and gold and demonstrate the capabilities of the two configurations for super-resolved near-field mid-infrared hyperspectral imaging and that the simple use of a properly chosen bandpass filter on the detector allows one to image the spatial distribution of materials with sub-wavelength resolution by studying the contrast in the near-field images.

Peragut, Florian; De Wilde, Yannick, E-mail: yannick.dewilde@espci.fr [ESPCI ParisTech, PSL Research University, CNRS, Institut Langevin, 1 rue Jussieu, F-75005, Paris (France); Brubach, Jean-Blaise; Roy, Pascale [Société Civile Synchrotron SOLEIL, L'Orme des Merisiers, St-Aubin BP48, 91192 Gif-sur-Yvette Cedex (France)

2014-06-23T23:59:59.000Z

28

Single Molecule Emission Characteristics in Near-Field Microscopy  

Science Journals Connector (OSTI)

In near-field scanning optical microscopy (NSOM), the measured fluorescence lifetime of a single dye molecule can be shortened or lengthened, sensitively dependent on the relative position between the molecule and aluminum coated fiber tip. The modified lifetimes and other emission characteristics are simulated by solving Maxwell equations with the finite-difference time-domain (FDTD) method. The 2D computation reveals insight into the lifetime behaviors and provides guidance for nonperturbative spectroscopic measurements with NSOM. This new methodology is capable of predicting molecular emission properties in front of a metal/dielectric interface of arbitrary geometry.

Randy X. Bian; Robert C. Dunn; X. Sunney Xie; P. T. Leung

1995-12-25T23:59:59.000Z

29

Mapping Magnetic Near-Field Distributions of Plasmonic Nanoantennas  

Science Journals Connector (OSTI)

However, standard far-field optical microscopy methods have insufficient resolution and provide no information about the electromagnetic near-fields. ... The top right panel of Figure 3a illustrates how the charges and magnetic near-field (green circles) at the probe aperture line up with the charge distribution and magnetic near-field of the SPR mode. ... and magnetic field lines and Poynting vector distributions are reconstructed in a vol. ...

Denitza Denkova; Niels Verellen; Alejandro V. Silhanek; Ventsislav K. Valev; Pol Van Dorpe; Victor V. Moshchalkov

2013-03-06T23:59:59.000Z

30

Guided optical modes in randomly textured ZnO thin films imaged by near-field scanning optical K. Bittkau* and R. Carius  

E-Print Network [OSTI]

relevance. In particular, when designing thin-film solar cells and light emitting diodes LEDs , ran- domly

Peinke, Joachim

31

Inverse scattering for rotationally scanned optical coherence tomography  

E-Print Network [OSTI]

Inverse scattering for rotationally scanned optical coherence tomography Daniel L. Marks, Tyler S May 16, 2006; posted May 26, 2006 (Doc. ID 67358) Optical coherence tomography of luminal structures coherence tomography1,2 (OCT), is determined in large part by the degree to which the images provide

Bhargava, Rohit

32

Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade laser  

SciTech Connect (OSTI)

Utilizing a broadly-tunable external cavity quantum cascade laser for scattering-type scanning near-field optical microscopy (s-SNOM), we measure infrared spectra of explosives particles by probing characteristic nitro-group resonances in the 7.1-7.9 µm wavelength range. Measurements are presented with spectral resolution of 0.25 cm-1, spatial resolution of 25 nm, <100 attomolar sensitivity, and at a rapid acquisition time of 90 s per spectrum. We demonstrate high reproducibility of the acquired s-SNOM spectra with very high signal-to-noise ratios and relative noise of <0.02 in self-homodyne detection.

Craig, Ian M.; Taubman, Matthew S.; Lea, Alan S.; Phillips, Mark C.; Josberger, Erik E.; Raschke, Markus Bernd

2013-12-16T23:59:59.000Z

33

Near-Field Analysis of Bright and Dark Modes on Plasmonic Metasurfaces Showing Extraordinary Suppressed Transmission  

E-Print Network [OSTI]

Plasmonic metasurfaces are investigated that consist of a sub wavelength line pattern in an ultrathin (~ 10 nm) silver film, designed for extraordinarily suppressed transmission (EOST) in the visible spectral range. Measurements with a near-field scanning optical microscope (NSOM) demonstrate that far field irradiation creates resonant excitations of antenna like (bright) modes that are localized on the metal ridges. In contrast, bound (dark) surface plasmon polaritons (SPPs) launched from an NSOM tip propagate well across the metasurface, preferentially perpendicular to the grating lines.

Dobmann, Sabine; Ploss, Daniel; Peschel, Ulf

2014-01-01T23:59:59.000Z

34

Near-field radiative heat transfer for structured surfaces  

E-Print Network [OSTI]

We apply an analytical approach for determining the near-field radiative heat transfer between a metallic nanosphere and a planar semi-infinite medium with some given surface structure. This approach is based on a perturbative expansion, and evaluated to first order in the surface profile. With the help of numerical results obtained for some simple model geometries we discuss typical signatures that should be obtainable with a near-field scanning thermal microscope operated in either constant-height or constant-distance mode.

Svend-Age Biehs; Oliver Huth; Felix Rüting

2011-03-15T23:59:59.000Z

35

Modulation of near-field heat transfer between two gratings  

E-Print Network [OSTI]

We present a theoretical study of near-field heat transfer between two uniaxial anisotropic planar structures. We investigate how the distance and relative orientation (with respect to their optical axes) between the objects affect the heat flux. In particular, we show that by changing the angle between the optical axes it is possible in certain cases to modulate the net heat flux up to 90% at room temperature, and discuss possible applications of such a strong effect.

Svend-Age Biehs; Felipe S. S. Rosa; Philippe Ben-Abdallah

2011-05-18T23:59:59.000Z

36

Video Scanning Hartmann Optical Testing of State-of-the-Art Parabolic Trough Concentrators: Preprint  

SciTech Connect (OSTI)

This paper describes the Video Scanning Hartmann Optical Test System (VSHOT) used to optically test parabolic trough designs by both Solargenix and Industrial Solar Technology.

Wendelin, T.; May, K.; Gee, R.

2006-06-01T23:59:59.000Z

37

Nanoindentation and near-field spectroscopy of single semiconductor quantum dots  

Science Journals Connector (OSTI)

Low-temperature near-field scanning optical microscopy was used to study the dependence of the emission spectra of single self-organized InAs on GaAs, InAs on AlAs and InP on GaInP quantum dots (QDs) on contact pressure exerted by a near-field optical fiber tip (nanoindentation). A large energy shift (up to 150 meV), broadening (up to 10 meV), and intensity increase (up to one order of magnitude) of single QD emission lines have been observed at tip compressions up to 70 nm. Ground state energy shift rates from 0.5 to 3.5 meV/nm have been measured for different aperture types (rounded and flat, metal coated and uncoated) and sizes (50–300 nm) in agreement with numerical calculations using Picus–Bir orbital-strain Hamiltonian. A reduction of the hydrostatic pressure coefficient due to a nonuniform In distribution in self-organized QDs has been observed. Anomalously strong lateral inhomogeneity of the local stress field has been observed.

A. M. Mintairov; K. Sun; J. L. Merz; C. Li; A. S. Vlasov; D. A. Vinokurov; O. V. Kovalenkov; V. Tokranov; S. Oktyabrsky

2004-04-05T23:59:59.000Z

38

Visual Scanning Hartmann Optical Tester (VSHOT) Uncertainty Analysis (Milestone Report)  

SciTech Connect (OSTI)

In 1997, an uncertainty analysis was conducted of the Video Scanning Hartmann Optical Tester (VSHOT). In 2010, we have completed a new analysis, based primarily on the geometric optics of the system, and it shows sensitivities to various design and operational parameters. We discuss sources of error with measuring devices, instrument calibrations, and operator measurements for a parabolic trough mirror panel test. These help to guide the operator in proper setup, and help end-users to understand the data they are provided. We include both the systematic (bias) and random (precision) errors for VSHOT testing and their contributions to the uncertainty. The contributing factors we considered in this study are: target tilt; target face to laser output distance; instrument vertical offset; laser output angle; distance between the tool and the test piece; camera calibration; and laser scanner. These contributing factors were applied to the calculated slope error, focal length, and test article tilt that are generated by the VSHOT data processing. Results show the estimated 2-sigma uncertainty in slope error for a parabolic trough line scan test to be +/-0.2 milliradians; uncertainty in the focal length is +/- 0.1 mm, and the uncertainty in test article tilt is +/- 0.04 milliradians.

Gray, A.; Lewandowski, A.; Wendelin, T.

2010-10-01T23:59:59.000Z

39

Near-Field Nanopatterning and Associated Energy Transport Analysis with Thermoreflectance  

E-Print Network [OSTI]

Laser nano-patterning with near-field optical microscope (NSOM) and the associated energy transport analysis are achieved in this study. Based on combined experimental/theoretical analyses, it is found that laser nano-patterning with a NSOM...

Soni, Alok

2013-05-31T23:59:59.000Z

40

Near-field diffractive elements Daniel Marks  

E-Print Network [OSTI]

by a near-field diffractive element (NDE) that scatters the high-spatial-frequency components of the field susceptibility r , and the NDE is described by the susceptibilty r . The field obeys the equation 2 U r +k0 2 U r to first order in both the NDE and the sample susceptibilities. It is assumed that the background terms

Bhargava, Rohit

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Inverse scattering for frequency-scanned full-field optical coherence tomography  

E-Print Network [OSTI]

Inverse scattering for frequency-scanned full-field optical coherence tomography Daniel L. Marks-field optical coherence tomography (OCT) is able to image an entire en face plane of scatterers simulta- neously: 100.3010, 110.4500. 1. INTRODUCTION The capabilities of optical coherence tomography1,2 (OCT

Bhargava, Rohit

42

Optical scanning apparatus for indicia imprinted about a cylindrical axis  

DOE Patents [OSTI]

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.

Villarreal, Richard A. (Kennewick, WA)

1987-01-01T23:59:59.000Z

43

Optically Fabricated Three Dimensional Nanofluidic Mixers for Microfluidic  

E-Print Network [OSTI]

Optically Fabricated Three Dimensional Nanofluidic Mixers for Microfluidic Devices Seokwoo Jeon in the channels of microfluidic systems. Near field scanning optical measurements reveal the optics associated with the fabrication process and the key features that enable its application to the area of microfluidics. Confocal

Rogers, John A.

44

Convergence analysis in near-field imaging  

E-Print Network [OSTI]

Jul 25, 2014 ... inverse scattering problem is that of determining the nature of the ... A comprehensive review can be found in [7] on diffractive optics tech-.

Gang Bao

2014-07-24T23:59:59.000Z

45

Near-field/altered-zone models report  

SciTech Connect (OSTI)

The U.S. Department of Energy is studying Yucca Mountain as the possible site for the first underground repository for permanent disposal of spent fuel from commercial nuclear reactors as well as for other types high-level nuclear waste. Emplacement of high-level radioactive waste, especially commercial spent nuclear fuel (CSNF), in Yucca Mountain will release a large amount of heat into the rock above and below the repository. The heating rate will decrease with time, creating a thermal pulse. Over a period of several thousand years, the rock temperature will rise initially, then drop when the production of decay heat falls below the rate at which heat escapes from the hot zone. Besides raising the rock temperature, much of this heat will vaporize water, which will then condense in cooler regions. The condensate is likely to form a gravity-driven heat pipe above the repository, creating the possibility that water may drain back onto the waste packages (WPs) or that it may ''shed'' through the pillars between emplacement drifts. The long-term importance of these effects has been investigated through the development, testing, and application of thermohydrologic (TH) models. Other effects, such coupled chemical and mechanical processes, may also influence the movement of water above, within, and below the emplacement drifts. A recent report on thermally driven coupled processes (Hardin and Chesnut, 1997) provides a qualitative assessment of the probable significance of these processes for the Yucca Mountain Site Characterization Project (YMSCP) and is the phenomenological framework for the present report. This report describes the conceptual and numerical models that have been developed to predict the thermal, mechanical, hydrologic, and chemical responses to the cumulative heat production of the potential host rock at Yucca Mountain. As proposed, the repository horizon will be situated within the Topopah Spring tuff, in the adjacent middle nonlithophysal and lower lithophysal units. These units are made up of moderately to densely welded, devitrified, fractured tuff. The rock's chemical composition is comparable to that of typical granite, but has textural features and mineralogical characteristics of large-scale, silicic volcanism. Because the repository horizon will be approximately 300 m below the ground surface and 200 m above the water table, the repository will be partially saturated. The welded tuff matrix in the host units is highly impermeable, but water and gas flow readily through fractures. The degree of fracturing in these units is highly variable, and the hydrologic significance of fracturing is an important aspect of site investigation. This report describes the characterization and modeling of a region around the potential repository--the altered zone--a region in which the temperature will be increased significantly by waste-generated heat. Numerical simulation has shown that, depending on the boundary conditions, rock properties, and repository design features incorporated in the models, the altered zone (AZ) may extend from the water table to the ground surface. This report also describes models of the near field, the region comprising the repository emplacement drifts and the surrounding rock, which are critical to the performance of engineered components. Investigations of near-field and altered-zone (NF/AZ) processes support the design of underground repository facilities and engineered barriers and also provide constraint data for probabilistic calculations of waste-isolation performance (i.e., performance assessment). The approach to investigation, which is an iterative process involving hypothesis testing and experimentation, has relied on conceptualizing engineered barriers and on performance analysis. This report is a collection, emphasizing conceptual and numerical models, of the recent results contributed from studies of NF/AZ processes and of quantitative measures of NF/AZ performance. The selection and presentation of contributions are intended to show the iterative development of understand

Hardin, E. L., LLNL

1998-03-01T23:59:59.000Z

46

Curve crossing and negative refraction in simulations of near-field coupled metallic nanoparticle arrays  

E-Print Network [OSTI]

Curve crossing and negative refraction in simulations of near-field coupled metallic nanoparticle-polariton LSPP dispersion on regular arrays of metal nanoparticles in the weak-field and weak-damping limits nanoparticle ar- rays to guide electromagnetic energy of optical frequencies along geometries smaller than

Baer, Roi

47

IR SNOM - Infrared Near-field Nanoimaging | EMSL  

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

Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade laser. Utilizing a broadly-tunable external cavity quantum cascade laser for...

48

Infrared near-field spectroscopy of trace explosives using an...  

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

spectroscopy of trace explosives using an external cavity quantum cascade laser. Infrared near-field spectroscopy of trace explosives using an external cavity quantum...

49

Graphene-assisted near-field radiative heat transfer between corrugated polar materials  

SciTech Connect (OSTI)

Graphene has attracted great attention in nanoelectronics, optics, and energy harvesting. Here, the near-field radiative heat transfer between graphene-covered corrugated silica is investigated based on the exact scattering theory. It is found that graphene can improve the radiative heat flux between silica gratings by more than one order of magnitude and alleviate the performance sensitivity to lateral shift. The underlying mechanism is mainly attributed to the improved photon tunneling of modes away from phonon resonances. Besides, coating with graphene leads to nonlocal radiative transfer that breaks Derjaguin's proximity approximation and enables corrugated silica to outperform bulk silica in near-field radiation.

Liu, X. L.; Zhang, Z. M., E-mail: zhuomin.zhang@me.gatech.edu [G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2014-06-23T23:59:59.000Z

50

Spin microscope based on optically detected magnetic resonance  

DOE Patents [OSTI]

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2007-12-11T23:59:59.000Z

51

Spin microscope based on optically detected magnetic resonance  

DOE Patents [OSTI]

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2010-06-29T23:59:59.000Z

52

Spin microscope based on optically detected magnetic resonance  

DOE Patents [OSTI]

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2009-11-10T23:59:59.000Z

53

Spin microscope based on optically detected magnetic resonance  

DOE Patents [OSTI]

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2009-10-27T23:59:59.000Z

54

X-ray optics for scanning fluorescence microscopy and other applications  

SciTech Connect (OSTI)

Scanning x-ray fluorescence microscopy is analogous to scanning electron microscopy. Maps of chemical element distribution are produced by scanning with a very small x-ray beam. Goal is to perform such scanning microscopy with resolution in the range of <1 to 10 {mu}m, using standard laboratory x-ray tubes. We are investigating mirror optics in the Kirkpatrick-Baez (K-B) configuration. K-B optics uses two curved mirrors mounted orthogonally along the optical axis. The first mirror provides vertical focus, the second mirror provides horizontal focus. We have used two types of mirrors: synthetic multilayers and crystals. Multilayer mirrors are used with lower energy radiation such as Cu K{alpha}. At higher energies such as Ag K{alpha}, silicon wafers are used in order to increase the incidence angles and thereby the photon collection efficiency. In order to increase the surface area of multilayers which reflects x-rays at the Bragg angle, we have designed mirrors with the spacing between layers graded along the optic axis in order to compensate for the changing angle of incidence. Likewise, to achieve a large reflecting surface with silicon, the wafers are placed on a specially designed lever arm which is bent into a log spiral by applying force at one end. In this way, the same diffracting angle is maintained over the entire surface of the wafer, providing a large solid angle for photon collection.

Ryon, R.W. [Lawrence Livermore National Lab., CA (United States); Warburton, W.K. [X-Ray Instrumentation Associates, Menlo Park, CA (United States)

1992-05-01T23:59:59.000Z

55

Coherent Time-Stretch Transform for Near-Field Spectroscopy  

E-Print Network [OSTI]

losses results in reduction in peak power and loss of sensitivity; a key innovation has been diffraction theoryVthe Fraunhofer limit. We may also consider the temporal near-field regime in analogy

Jalali. Bahram

56

Apparatus comprising a tunable nanomechanical near-field grating and method for controlling far-field emission  

DOE Patents [OSTI]

A tunable nanomechanical near-field grating is disclosed which is capable of varying the intensity of a diffraction mode of an optical output signal. The tunable nanomechanical near-field grating includes two sub-gratings each having line-elements with width and thickness less than the operating wavelength of light with which the grating interacts. Lateral apertures in the two sub-gratings are formed from the space between one line-element of the first sub-grating and at least one line-element of the second sub-grating. One of the sub-gratings is capable of motion such that at least one of aperture width and aperture depth changes, causing a perturbation to the near-field intensity distribution of the tunable nanomechanical near-field grating and a corresponding change to the far-field emission of thereof.

Carr, Dustin Wade (Albuquerque, NM); Bogart, Gregory Robert (Corrales, NM)

2007-02-06T23:59:59.000Z

57

ihLSEVIFR Optical Materials 3 (1994) 115--121 Absolute non-radiative energy conversion efficiency scanning  

E-Print Network [OSTI]

, in optical materials. 1. Introduction reported optical absorptions and optical-to-thermal energy conversion of transparent, high-qual- which PPES 11NR studies have been reported have itylaser materials, ~NR (A) the absence of irre- radiativecenters during the quadrature scan, as corn- producible thermal resistances

Mandelis, Andreas

58

System and method for chromatography and electrophoresis using circular optical scanning  

DOE Patents [OSTI]

A system and method is disclosed for chromatography and electrophoresis using circular optical scanning. One or more rectangular microchannel plates or radial microchannel plates has a set of analysis channels for insertion of molecular samples. One or more scanning devices repeatedly pass over the analysis channels in one direction at a predetermined rotational velocity and with a predetermined rotational radius. The rotational radius may be dynamically varied so as to monitor the molecular sample at various positions along a analysis channel. Sample loading robots may also be used to input molecular samples into the analysis channels. Radial microchannel plates are built from a substrate whose analysis channels are disposed at a non-parallel angle with respect to each other. A first step in the method accesses either a rectangular or radial microchannel plate, having a set of analysis channels, and second step passes a scanning device repeatedly in one direction over the analysis channels. As a third step, the scanning device is passed over the analysis channels at dynamically varying distances from a centerpoint of the scanning device. As a fourth step, molecular samples are loaded into the analysis channels with a robot.

Balch, Joseph W. (Livermore, CA); Brewer, Laurence R. (Oakland, CA); Davidson, James C. (Livermore, CA); Kimbrough, Joseph R. (Pleasanton, CA)

2001-01-01T23:59:59.000Z

59

Near-Field Radiative Heat Transfer between Metamaterials coated with Silicon Carbide Film  

E-Print Network [OSTI]

In this letter, we study the near-field radiative heat transfer between two metamaterial substrates coated with silicon carbide (SiC) thin films. It is known that metamaterials can enhance the near-field heat transfer over ordinary materials due to excitation of magnetic plasmons associated with s polarization, while strong surface phonon polariton exists for SiC.By careful tuning of the optical properties of metamaterial it is possible to excite electrical and magnetic resonance for the metamaterial and surface phonon polaritons for SiC at different spectral regions, resulting in the enhanced heat transfer. The effect of the SiC film thickness at different vacuum gaps is investigated. Results obtained from this study will be beneficial for application of thin film coatings for energy harvesting.

Basu, Soumyadipta; Wang, Liping

2014-01-01T23:59:59.000Z

60

Thermal heat radiation, near-field energy density and near-field radiative heat transfer of coated materials  

E-Print Network [OSTI]

We investigate the thermal radiation and thermal near-field energy density of a metal-coated semi-infinite body for different substrates. We show that the surface polariton coupling within the metal coating leads to an enhancement of the TM-mode part of the thermal near-field energy density when a polar substrate is used. In this case the result obtained for a free standing metal film is retrieved. In contrast, in the case of a metal substrate there is no enhancement in the TM-mode part, as can also be explained within the framework of surface plasmon coupling within the coating. Finally, we discuss the influence of the enhanced thermal energy density on the near-field radiative heat transfer between a simple semi-infinite and a coated semi-infinite body for different material combinations.

Svend-Age Biehs

2011-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Near-field heat transfer between gold nanoparticle arrays  

SciTech Connect (OSTI)

The radiative heat transfer between gold nanoparticle layers is presented using the coupled dipole method. Gold nanoparticles are modelled as effective electric and magnetic dipoles interacting via electromagnetic fluctuations. The effect of higher-order multipoles is implemented in the expression of electric polarizability to calculate the interactions at short distances. Our findings show that the near-field radiation reduces as the radius of the nanoparticles is increased. Also, the magnetic dipole contribution to the heat exchange becomes more important for larger particles. When one layer is displayed in parallel with respect to the other layer, the near-field heat transfer exhibits oscillatory-like features due to the influence of the individual nanostructures. Further details about the effect of the nanoparticles size are also discussed.

Phan, Anh D., E-mail: anhphan@mail.usf.edu [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States); Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Ba Dinh, Hanoi 10000 (Viet Nam); Phan, The-Long, E-mail: ptlong2512@yahoo.com [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Woods, Lilia M. [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States)

2013-12-07T23:59:59.000Z

62

Near-field effects of asteroid impacts in deep water  

SciTech Connect (OSTI)

Our previous work has shown that ocean impacts of asteroids below 500 m in diameter do not produce devastating long-distance tsunamis. Nevertheless, a significant portion of the ocean lies close enough to land that near-field effects may prove to be the greatest danger from asteroid impacts in the ocean. Crown splashes and central jets that rise up many kilometres into the atmosphere can produce, upon their collapse, highly non-linear breaking waves that could devastate shorelines within a hundred kilometres of the impact site. We present illustrative calculations, in two and three dimensions, of such impacts for a range of asteroid sizes and impact angles. We find that, as for land impacts, the greatest dangers from oceanic impacts are the short-term near-field, and long-term atmospheric effects.

Gisler, Galen R [Los Alamos National Laboratory; Weaver, Robert P [Los Alamos National Laboratory; Gittings, Micheal L [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

63

Near-field microwave microscopy of high-? oxides grown on graphene with an organic seeding layer  

SciTech Connect (OSTI)

Near-field scanning microwave microscopy (SMM) is used for non-destructive nanoscale characterization of Al{sub 2}O{sub 3} and HfO{sub 2} films grown on epitaxial graphene on SiC by atomic layer deposition using a self-assembled perylene-3,4,9,10-tetracarboxylic dianhydride seeding layer. SMM allows imaging of buried inhomogeneities in the dielectric layer with a spatial resolution close to 100?nm. The results indicate that, while topographic features on the substrate surface cannot be eliminated as possible sites of defect nucleation, the use of a vertically heterogeneous Al{sub 2}O{sub 3}/HfO{sub 2} stack suppresses formation of large outgrowth defects in the oxide film, ultimately improving lateral uniformity of the dielectric film.

Tselev, Alexander, E-mail: tseleva@ornl.gov; Kalinin, Sergei V. [Oak Ridge National Laboratory, Center for Nanophase Materials Sciences, Oak Ridge, Tennessee 37831 (United States)] [Oak Ridge National Laboratory, Center for Nanophase Materials Sciences, Oak Ridge, Tennessee 37831 (United States); Sangwan, Vinod K.; Jariwala, Deep; Lauhon, Lincoln J. [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States)] [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Marks, Tobin J.; Hersam, Mark C. [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States) [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Department of Chemistry, Northwestern University, Evanston, Illinois 60208 (United States)

2013-12-09T23:59:59.000Z

64

Materials Science and Engineering B 120 (2005) 9194 Optical index profile at an antiparallel ferroelectric domain  

E-Print Network [OSTI]

-antisites, NbLi (which are excess Nb atoms at Li locations), and lithium vacancies denoted by VLi. The de- fect ferroelectric domain wall in lithium niobate Sungwon Kim, Venkatraman Gopalan Materials Research Institute-stoichiometric lithium niobate. This is imaged using near-field scanning optical microscopy. A detailed modeling

Gopalan, Venkatraman

65

Near-field thermal radiation transfer controlled by plasmons in graphene  

E-Print Network [OSTI]

It is shown that thermally excited plasmon-polariton modes can strongly mediate, enhance, and tune the near-field radiation transfer between two closely separated graphene sheets. The dependence of near-field heat exchange ...

Ilic, Ognjen

66

Tungsten Nanowire Based Hyperbolic Metamaterial Emitters for Near-field Thermophotovoltaic Applications  

E-Print Network [OSTI]

Recently, near-field radiative heat transfer enhancement across nanometer vacuum gaps has been intensively studied between two hyperbolic metamaterials (HMMs) due to unlimited wavevectors and high photonic density of state. In this work, we theoretically analyze the energy conversion performance of a thermophotovoltaic (TPV) cell made of In0.2Ga0.8Sb when paired with a HMM emitter composed of tungsten nanowire arrays embedded in Al2O3 host at nanometer vacuum gaps. Fluctuational electrodynamics integrated with effective medium theory and anisotropic thin-film optics is used to calculate the near-field radiative heat transfer. It is found that the spectral radiative energy is enhanced by the epsilon-near-zero and hyperbolic modes at different polarizations. As a result, the power output from a semi-infinite TPV cell is improved by 1.85 times with the nanowire HMM emitter over that with a plain tungsten emitter at a vacuum gap of 10 nm. Moreover, by using a thin TPV cell with 10 um thickness, the conversion eff...

Chang, Jui-Yung; Wang, Liping

2014-01-01T23:59:59.000Z

67

Etched chalcogenide fibers for near-field infrared scanning microscopy M. A. Unger,a)  

E-Print Network [OSTI]

Electron Laser Center, Stanford, California 94305-4085 Received 12 December 1997; accepted for publication by a sulfur-selenide cladding, which is in turn coated with a polymer such as polyamide. For use in a near cladding surrounding the core, and etching the chalcogenide fiber core to a sharp point. Removal

Palanker, Daniel

68

A novel mathematical model for controllable near-field electrospinning  

SciTech Connect (OSTI)

Near-field electrospinning (NFES) had better controllability than conventional electrospinning. However, due to the lack of guidance of theoretical model, precise deposition of micro/nano fibers could only accomplished by experience. To analyze the behavior of charged jet in NFES using mathematical model, the momentum balance equation was simplified and a new expression between jet cross-sectional radius and axial position was derived. Using this new expression and mass conservation equation, expressions for jet cross-sectional radius and velocity were derived in terms of axial position and initial jet acceleration in the form of exponential functions. Based on Slender-body theory and Giesekus model, a quadratic equation for initial jet acceleration was acquired. With the proposed model, it was able to accurately predict the diameter and velocity of polymer fibers in NFES, and mathematical analysis rather than experimental methods could be applied to study the effects of the process parameters in NFES. Moreover, the movement velocity of the collector stage can be regulated by mathematical model rather than experience. Therefore, the model proposed in this paper had important guiding significance to precise deposition of polymer fibers.

Ru, Changhai, E-mail: rchhai@gmail.com, E-mail: luojun@shu.edu.cn [College of Automation, Harbin Engineering University, Harbin 150001 (China) [College of Automation, Harbin Engineering University, Harbin 150001 (China); Robotics and Microsystems Center, Soochow University, Suzhou 215021 (China); Chen, Jie; Shao, Zhushuai [Robotics and Microsystems Center, Soochow University, Suzhou 215021 (China)] [Robotics and Microsystems Center, Soochow University, Suzhou 215021 (China); Pang, Ming [College of Automation, Harbin Engineering University, Harbin 150001 (China)] [College of Automation, Harbin Engineering University, Harbin 150001 (China); Luo, Jun, E-mail: rchhai@gmail.com, E-mail: luojun@shu.edu.cn [School of Mechatronics Engineering and Automation, Shanghai University, Shanghai 200072 (China)] [School of Mechatronics Engineering and Automation, Shanghai University, Shanghai 200072 (China)

2014-01-15T23:59:59.000Z

69

Near-field modeling in Frenchman Flat, Nevada Test Site  

SciTech Connect (OSTI)

The US Department of Energy (DOE) is investigating the effects of nuclear testing in underground test areas (the UGTA program) at the Nevada Test Site. The principal focus of the UGTA program is to better understand and define subsurface radionuclide migration. The study described in this report focuses on the development of tools for generating maps of hydrogeologic characteristics of subsurface Tertiary volcanic units at the Frenchman Flat corrective Action Unit (CAU). The process includes three steps. The first step involves generation of three-dimensional maps of the geologic structure of subsurface volcanic units using geophysical logs to distinguish between two classes: densely welded tuff and nonwelded tuff. The second step generates three-dimensional maps of hydraulic conductivity utilizing the spatial distribution of the two geologic classes obtained in the first step. Each class is described by a correlation structure based on existing data on hydraulic conductivity, and conditioned on the generated spatial location of each class. The final step demonstrates the use of the maps of hydraulic conductivity for modeling groundwater flow and radionuclide transport in volcanic tuffs from an underground nuclear test at the Frenchman Flat CAU. The results indicate that the majority of groundwater flow through the volcanic section occurs through zones of densely welded tuff where connected fractures provide the transport pathway. Migration rates range between near zero to approximately four m/yr, with a mean rate of 0.68 m/yr. This report presents the results of work under the FY96 Near-Field Modeling task of the UGTA program.

Pohlmann, K.; Shirley, C.; Andricevic, R.

1996-12-01T23:59:59.000Z

70

NEAR-FIELD IMAGING OF OBSTACLES Peijun Li and Yuliang Wang  

E-Print Network [OSTI]

applications in modern science and technology, such as nanotechnology, biology, information storage, and surface chemistry. Using near-field imaging, we

2014-06-30T23:59:59.000Z

71

High resolution in situ magneto-optic Kerr effect and scanning tunneling microscopy setup with all optical components in UHV  

E-Print Network [OSTI]

optical components in UHV A. Lehnert, P. Buluschek, N. Weiss, J. Giesecke, M. Treier, S. Rusponi, and H UHV chamber. In addition, sample preparation, growth of nanostructures or films, as well

Brune, Harald

72

Phonon-Polaritons enhance near field thermal transfer across the phase transition of VO2  

E-Print Network [OSTI]

conductivity contrasts of larger than an order of magnitude exist for switchable materials. Yet the control or very low temperatures. A first effort of rectification of thermal transfer in near field by 40 shown that whereas thermal conductivity and far field heat transfer are difficult to tune, in near field

Paris-Sud XI, Université de

73

Near-Field Imaging with Sound: An Acoustic STM Model  

Science Journals Connector (OSTI)

The invention of scanning tunneling microscopy(STM) 30 years ago opened up a visual window to the nano-world and sparked off a bunch of new methods for investigating and controlling matter and its transformations at the atomic and molecular level.1 However an adequate theoretical understanding of the method is demanding; STM images can be considered quantum theory condensed into a pictorial representation. A hands-on model is presented for demonstrating the imaging principles in introductory teaching. It uses sound waves and computer visualization to create mappings of acoustic resonators. The macroscopic simile is made possible by quantum-classical analogies between matter and sound waves. Grounding STM in acoustic experience may help to make the underlying quantum concepts such as tunneling less abstract to students.

Manfred Euler

2012-01-01T23:59:59.000Z

74

Investigating the Optical Properties of Dislocations by Scanning Transmission Electron Microscopy  

E-Print Network [OSTI]

investigation for solid-state lighting and display applications, and dislocations are known to be nonradiative the radiative pathway and contribute to the enormous savings in energy use and greenhouse gas emissions expected with efficient solid-state lighting. CL Studies of Dislocations One of the key advantages of a scanning micro

Pennycook, Steve

75

Vibration Measurement Using a Novel Fibre-Optic Electronically-Scanned White-Light Interferometer  

Science Journals Connector (OSTI)

Optical interferometry is a widely used technique for the measurement of vibrations of a range of industrial components.1,2 It has a wide dynamic range and a high sensitivity. 2,3 However, these configurations di...

R. H. Marshall; Y. N. Ning; A. W. Palmer…

1997-01-01T23:59:59.000Z

76

Near?field–far?field transition of a finite line source using incoherent light: A student laboratory experiment  

Science Journals Connector (OSTI)

A simple experiment employing low cost apparatus is presented which demonstrates the falloff of intensity with distance and the transition from the near field to the far field of a line source filament incandescent light bulb. A derivation of the Poynting vector as a function of the distance away from the filament is presented which shows an exact correspondence to the derivation for the electric field from a finite line charge source in electrostatics. The experimental data of power vs distance from the filament show an inverse first power of the distance falloff in the near field with a smooth transition to an inverse square law behavior in the far field in good agreement with the theoretical expression when corrections for the measured angular response of the detector are included. The experiment provides an illustration of the inverse square law falloff of intensity at large distances from the source experience with simple concepts and techniques of optical radiometry and incoherent light sources and the analogy between incoherent light sources and electrostatics in an undergraduate laboratory. An additional short experiment provides an illustration of electrical?to?optical power conversion efficiency and temperature dependent resistance associated with electron–phonon scattering in metals. A derivation of isotropic unpolarized elementary radiators from anisotropic dipole radiation is presented in the Appendix.

Xincheng Yan; Yixin Yu; Louis Shen; Keith H. Wanser

1995-01-01T23:59:59.000Z

77

Overcoming the black body limit in plasmonic and graphene near-field thermophotovoltaic systems  

E-Print Network [OSTI]

Near-field thermophotovoltaic (TPV) systems with carefully tailored emitter-PV properties show large promise for a new temperature range (600 – 1200K) solid state energy conversion, where conventional thermoelectric (TE) ...

Ilic, Ognjen

78

Chiral-field microwave antennas (Chiral microwave near fields for far-field radiation)  

E-Print Network [OSTI]

In a single-element structure we obtain a radiation pattern with a squint due to chiral microwave near fields originated from a magnetostatic-mode ferrite disk. At the magnetostatic resonances, one has strong subwavelength localization of energy of microwave radiation. Magnetostatic oscillations in a thin ferrite disk are characterized by unique topological properties: the Poynting-vector vortices and the field helicity. The chiral-topology near fields allow obtaining unique phase structure distribution for far-field microwave radiation.

Kamenetskii, E O; Shavit, R

2015-01-01T23:59:59.000Z

79

Nanometric Optical Imaging Frontiers in Chemical Imaging  

E-Print Network [OSTI]

Nanometric Optical Imaging Frontiers in Chemical Imaging Seminar Series Presented by... Professor growing field which has provided for nanometric optical imaging in the near-field. Even though a variety of techniques are being developed with nanometric optical imaging potential, near-field optics remains the most

80

Report on Modeling Coupled Processes in the Near Field of a Clay Repository  

Broader source: Energy.gov (indexed) [DOE]

on Modeling Coupled Processes in the Near Field of a Clay on Modeling Coupled Processes in the Near Field of a Clay Repository Report on Modeling Coupled Processes in the Near Field of a Clay Repository Clay/shale has been considered as potential host rock for geological disposal of high-level radioactive waste throughout the world. Coupled thermal, hydrological, mechanical, and chemical (THMC) processes have a significant impact on the long-term safety of a clay repository. This report documents results from three R&D activities: (1) implementation and validation of constitutive relationships, (2) development of a discrete fracture network (DFN) model for investigating coupled processes in the excavation damaged zone, and (3) development of a THM model for the Full-Scale Emplacement Experiment tests at Mont Terri, Switzerland, for the

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

High energy photoelectron emission from gases using plasmonics enhanced near-fields  

E-Print Network [OSTI]

We study theoretically the photoelectron emission in noble gases using plasmonic enhanced near-fields. We demonstrate that these fields have a great potential to generate high energy electrons by direct mid-infrared laser pulses of the current femtosecond oscillator. Typically, these fields appear in the surroundings of plasmonic nanostructures, having different geometrical shape such as bow-ties, metallic waveguides, metal nanoparticles and nanotips, when illuminated by a short laser pulse. In here, we consider metal nanospheres, in which the spatial decay of the near-field of the isolated nanoparticle can be approximated by an exponential function according to recent attosecond streaking measurements. We establish that the strong nonhomogeneous character of the enhanced near-field plays an important role in the above threshold ionization (ATI) process and leads to a significant extension in the photoelectron spectra. In this work, we employ the time dependent Schr\\"odinger equation in reduced dimensions to ...

Ciappina, M F; Guichard, R; Pérez-Hernández, J A; Roso, L; Arnold, M; Siegel, T; Zaïr, A; Lewenstein, M

2013-01-01T23:59:59.000Z

82

Report on THMC Modeling of the Near Field Evolution of a Generic Clay  

Broader source: Energy.gov (indexed) [DOE]

on THMC Modeling of the Near Field Evolution of a Generic on THMC Modeling of the Near Field Evolution of a Generic Clay Repository: Model Validation and Demonstration Rev 2 Report on THMC Modeling of the Near Field Evolution of a Generic Clay Repository: Model Validation and Demonstration Rev 2 Shale and clay-rich rock formations have been considered as potential host rocks for geological disposal of high-level radioactive waste throughout the world. Coupled thermal, hydrological, mechanical, and chemical (THMC) processes have a significant impact on the long-term safety of a repository in this type of rocks. The validity of the two-part Hooke's model (TPHM), a new constitutive relationship, and associated formulations regarding rock hydraulic/mechanical properties is demonstrated by the consistency between observations from a mine-by test at the Mont Terri site

83

Near-field thermal radiation between hyperbolic metamaterials: Graphite and carbon nanotubes  

SciTech Connect (OSTI)

The near-field radiative heat transfer for two hyperbolic metamaterials, namely, graphite and vertically aligned carbon nanotubes (CNTs), is investigated. Graphite is a naturally existing uniaxial medium, while CNT arrays can be modeled as an effective anisotropic medium. Different hyperbolic modes can be separately supported by these materials in certain infrared regions, resulting in a strong enhancement in near-field heat transfer. It is predicted that the heat flux between two CNT arrays can exceed that between SiC plates at any vacuum gap distance and is about 10 times higher with a 10?nm gap.

Liu, X. L.; Zhang, R. Z.; Zhang, Z. M., E-mail: zhuomin.zhang@me.gatech.edu [G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2013-11-18T23:59:59.000Z

84

Optical near-field excitations on plasmonic nanoparticle-based structures  

E-Print Network [OSTI]

Modes, pp. 345­ 398 (John Wiley & Sons, Belfast, 1982). 2. J. B. Jackson, S. L. Westcott, L. R. Hirsch

85

Particle resuspension in the Columbia River plume near field Emily Y. Spahn,1  

E-Print Network [OSTI]

Particle resuspension in the Columbia River plume near field Emily Y. Spahn,1 Alexander R. Horner are used to investigate the mechanisms of sediment resuspension and entrainment into the plume. An east, the plume is much less stratified during low-discharge conditions, and large resuspension events

86

Graphene-based photovoltaic cells for near-field thermal energy conversion  

E-Print Network [OSTI]

Graphene-based photovoltaic cells for near-field thermal energy conversion Riccardo Messina-Sud 11, 2, Avenue Augustin Fresnel, 91127 Palaiseau Cedex, France. Thermophotovoltaic devices are energy-conversion , IR sensing and spectroscopy11,12 and has paved the way to a new generation of NTPV energy-conversion

Paris-Sud XI, Université de

87

Measuring near-field nanoparticle concentration profiles by correlating surface plasmon resonance reflectance with effective refractive index of nanofluids  

Science Journals Connector (OSTI)

Time-dependent and near-field nanoparticle concentrations are determined by correlating the surface plasmon resonance (SPR) reflectance intensities with the effective refractive...

Kim, Iltai; Kihm, Kenneth D

2010-01-01T23:59:59.000Z

88

Novel microwave near-field sensors for material characterization, biology, and nanotechnology  

E-Print Network [OSTI]

The wide range of interesting electromagnetic behavior of contemporary materials requires that experimentalists working in this field master many diverse measurement techniques and have a broad understanding of condensed matter physics and biophysics. Measurement of the electromagnetic response of materials at microwave frequencies is important for both fundamental and practical reasons. In this paper, we propose a novel near-field microwave sensor with application to material characterization, biology, and nanotechnology. The sensor is based on a subwavelength ferrite-disk resonator with magnetic-dipolar-mode (MDM) oscillations. Strong energy concentration and unique topological structures of the near fields originated from the MDM resonators allow effective measuring material parameters in microwaves, both for ordinary structures and objects with chiral properties.

Joffe, R; Shavit, R

2015-01-01T23:59:59.000Z

89

Fiber optic probe of free electron evanescent fields in the optical frequency range  

SciTech Connect (OSTI)

We introduce an optical fiber platform which can be used to interrogate proximity interactions between free-electron evanescent fields and photonic nanostructures at optical frequencies in a manner similar to that in which optical evanescent fields are sampled using nanoscale aperture probes in scanning near-field microscopy. Conically profiled optical fiber tips functionalized with nano-gratings are employed to couple electron evanescent fields to light via the Smith-Purcell effect. We demonstrate the interrogation of medium energy (30–50?keV) electron fields with a lateral resolution of a few micrometers via the generation and detection of visible/UV radiation in the 700–300?nm (free-space) wavelength range.

So, Jin-Kyu, E-mail: js1m10@orc.soton.ac.uk; MacDonald, Kevin F. [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Zheludev, Nikolay I. [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore 637371 (Singapore)

2014-05-19T23:59:59.000Z

90

Photothermal imaging scanning microscopy  

DOE Patents [OSTI]

Photothermal Imaging Scanning Microscopy produces a rapid, thermal-based, non-destructive characterization apparatus. Also, a photothermal characterization method of surface and subsurface features includes micron and nanoscale spatial resolution of meter-sized optical materials.

Chinn, Diane (Pleasanton, CA); Stolz, Christopher J. (Lathrop, CA); Wu, Zhouling (Pleasanton, CA); Huber, Robert (Discovery Bay, CA); Weinzapfel, Carolyn (Tracy, CA)

2006-07-11T23:59:59.000Z

91

Influence of roughness on near-field heat transfer between two plates  

E-Print Network [OSTI]

The surface roughness correction to the near-field heat transfer between two rough bulk materials is discussed by using second-order perturbation theory. The results allow for estimating the impact of surface roughness to the heat transfer in recent experiments between two plates and between a microsphere and a plate (using the Derjaguin approximation). Furthermore, we show that the proximity approximation for describing rough surfaces is valid for distances much smaller than the correlation length of the surface roughness even if the heat transfer is dominated by the coupling of surface modes.

Svend-Age Biehs; Jean-Jacques Greffet

2011-03-11T23:59:59.000Z

92

Geochemistry of Natural Components in the Near-Field Environment, Yucca Mountain, Nevada  

SciTech Connect (OSTI)

The natural near-field environment in and around the emplacement drifts of the proposed nuclear waste repository at Yucca Mountain, Nevada, includes the host rock, dust, seepage, and pore water. The chemical compositions of these components have been determined for assessing possible chemical and mineralogical reactions that may occur after nuclear waste is emplaced. The rock hosting the proposed repository is relatively uniform as shown by a mean coefficient of variation (CV) of 9 percent for major elements. In contrast, compositional variations of dust (bulk and water-soluble fractions), pore water, and seepage are large with mean CVs ranging from 28 to 64 percent. (authors)

Peterman, Zell E. [Yucca Mountain Project Branch, U.S. Geological Survey, MS 963 Box 25046 Denver Federal Center, 6th and Kipling Sts., Denver, CO, 80225 (United States); Oliver, Thomas A. [c/o U.S. Geological Survey, S.M. Stoller Corporation, MS 421 Box 25046 Denver Federal Center, Denver, CO, 80225 (United States)

2007-07-01T23:59:59.000Z

93

Spectrally resolved near-field intensity measurements from gain-guided twin-stripe laser diode arrays. Technical report  

SciTech Connect (OSTI)

Gain-guided twin-stripe laser diodes were observed that exhibit two distinct sets of longitudinal modes, one corresponding to a single near-field intensity profile centered between the stripes and the other to a double-lobe near-field distribution centered under the stripes. A large spectral separation between these two sets of modes was also measured. The double-lobe distribution probably results from a weak index guide, which occurs because of the decrease in the current density between stripes. The spectral separation between these two near-field modes is believed to be due to band filling.

Heflinger, D.G.; Fenner, W.R.

1988-11-01T23:59:59.000Z

94

Spectrally enhancing near-field radiative heat transfer by exciting magnetic polariton in SiC gratings  

E-Print Network [OSTI]

In the present work, we theoretically demonstrate, for the first time, that near field radiative transport between 1D periodic grating microstructures separated by subwavelength vacuum gaps can be significantly enhanced by exciting magnetic resonance or polariton. Fluctuational electrodynamics that incorporates scattering matrix theory with rigorous coupled wave analysis is employed to exactly calculate the near field radiative heat flux between two SiC gratings. Besides the well known coupled surface phonon polaritons (SPhP), an additional spectral radiative heat flux peak, which is due to magnetic polariton, is found within the phonon absorption band of SiC. The mechanisms, behaviors and interplays between magnetic polariton, coupled SPhP, single interface SPhP, and Wood's anomaly in the near field radiative transport are elucidated in detail. The findings will open up a new way to control near field radiative heat transfer by magnetic resonance with micro or nanostructured metamaterials.

Yang, Yue

2015-01-01T23:59:59.000Z

95

Near-field heat transfer between a nanoparticle and a rough surface  

E-Print Network [OSTI]

In this work we focus on the surface roughness correction to the near-field radiative heat transfer between a nanoparticle and a material with a rough surface utilizing a direct perturbation theory up to second order in the surface profile. We discuss the different distance regimes for the local density of states above the rough material and the heat flux analytically and numerically. We show that the heat transfer rate is larger than that corresponding to a flat surface at short distances. At larger distances it can become smaller due to surface polariton scattering by the rough surface. For distances much smaller than the correlation length of the surface profile, we show that the results converge to a proximity approximation, whereas in the opposite limit the rough surface can be replaced by an equivalent surface layer.

Svend-Age Biehs; Jean-Jacques Greffet

2011-03-11T23:59:59.000Z

96

Acceleration of electrons in the near field of lower hybrid frequency grills  

SciTech Connect (OSTI)

On Tore Supra, during lower hybrid (LH) current drive experiments, localized heat flux deposition is observed on plasma facing components such as the guard limiters of the LH grills or any object which is magnetically connected to the LH launching waveguides : modular low-field side limiters, ion cyclotron heating antennas, inner first wall. Similar observations have been made on the divertor plates and limiters of TdeV. In particular, by alternating the rf powers of the 2 grills of Tore Supra, it was shown that the heat flux on the tiles of the guard limiters is related to the local electric field but not with the convective power. We present here a model of acceleration of electrons in the near field of LH antennas. Results of this model are compared to experimental results.

Goniche, M. [JET Joint Undertaking, Abingdon, Oxfordshire (England); Mailloux, J.; Demers, Y.; Jacquet, P.; Bibet, P.; Froissard, P.; Rey, G.; Surle, F.; Tareb, M. [Centre canadien de fusion magnetique, Varnnes, Quebec, (Canada); Guilhem, D.; Harris, J.H. [Oak Ridge National Lab., TN (United States)

1996-09-01T23:59:59.000Z

97

Graphene-based photovoltaic cells for near-field thermal energy conversion  

E-Print Network [OSTI]

Thermophotovoltaic devices are energy-conversion systems generating an electric current from the thermal photons radiated by a hot body. In far field, the efficiency of these systems is limited by the thermodynamic Schockley-Queisser limit corresponding to the case where the source is a black body. On the other hand, in near field, the heat flux which can be transferred to a photovoltaic cell can be several orders of magnitude larger because of the contribution of evanescent photons. This is particularly true when the source supports surface polaritons. Unfortunately, in the infrared where these systems operate, the mismatch between the surface-mode frequency and the semiconductor gap reduces drastically the potential of this technology. Here we show that graphene-based hybrid photovoltaic cells can significantly enhance the generated power paving the way to a promising technology for an intensive production of electricity from waste heat.

Riccardo Messina; Philippe Ben-Abdallah

2012-07-05T23:59:59.000Z

98

Nanomechanical near-field grating apparatus and acceleration sensor formed therefrom  

DOE Patents [OSTI]

A nanomechanical near-field grating device is disclosed which includes two sub-gratings vertically spaced by a distance less than or equal to an operating wavelength. Each sub-grating includes a plurality of line-elements spaced apart by a distance less than or equal to the operating wavelength. A light source (e.g., a VCSEL or LED) can provide light at the operating wavelength for operation of the device. The device can operate as an active grating, with the intensity of a reflected or transmitted portion of the light varying as the relative positions of the sub-gratings are controlled by an actuator. The device can also operate as a passive grating, with the relative positions of the sub-gratings changing in response to an environmentally-induced force due to acceleration, impact, shock, vibration, gravity, etc. Since the device can be adapted to sense an acceleration that is directed laterally or vertically, a plurality of devices can be located on a common substrate to form a multi-axis acceleration sensor.

Carr, Dustin Wade (Albuquerque, NM); Bogart, Gregory Robert (Corrales, NM); Keeler, Bianca E. N. (Albuquerque, NM)

2008-03-04T23:59:59.000Z

99

Scanning evanescent electro-magnetic microscope  

DOE Patents [OSTI]

A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Alameda, CA)

2001-01-01T23:59:59.000Z

100

PHYSICAL REVIEW B 85, 155422 (2012) Near-field thermal radiation transfer controlled by plasmons in graphene  

E-Print Network [OSTI]

in graphene Ognjen Ilic,1,* Marinko Jablan,2 John D. Joannopoulos,1 Ivan Celanovic,3 Hrvoje Buljan,2 and Marin-field radiation transfer between two closely separated graphene sheets. The dependence of near-field heat exchange interband or intraband processes. We predict maximum transfer at low doping and for plasmons in two graphene

Soljaèiæ, Marin

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Far field extrapolation from near field interactions and shielding influence investigations based on a FE-PEEC coupling method  

E-Print Network [OSTI]

variable speed drive. The aim is to evaluate the near field interactions between the tracks, which have by the floating potentials tracks. Moreover, due to the frequency and power increases, the compliance to EMC limited by the considered frequency range and/or by the geometry complexity, and/or by the medium

Boyer, Edmond

102

Excitonic enhancement of nonradiative energy transfer from a quantum well in the optical near field of energy gradient quantum dots  

E-Print Network [OSTI]

. Phys. 111, 113714 (2012) Transport of indirect excitons in a potential energy gradient Appl. Phys. Lett 30 April 2012; published online 13 June 2012) We report strong exciton migration with an efficiency (QWs) to colloidal nanocrystal quantum dots (NQDs) is criti- cal to the energy efficiency in hybrid

Demir, Hilmi Volkan

103

Seismic Protection of Bridge Structures Using Shape Memory Alloy-Based Isolation Systems against Near-Field Earthquakes  

E-Print Network [OSTI]

SEISMIC PROTECTION OF BRIDGE STRUCTURES USING SHAPE MEMORY ALLOY-BASED ISOLATION SYSTEMS AGAINST NEAR-FIELD EARTHQUAKES A Dissertation by OSMAN ESER OZBULUT Submitted to the Office of Graduate Studies of Texas A&M University... Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Stefan Hurlebaus Committee Members, Jose Roesset Monique Head...

Ozbulut, Osman Eser

2012-02-14T23:59:59.000Z

104

Scanning computed confocal imager  

DOE Patents [OSTI]

There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

George, John S. (Los Alamos, NM)

2000-03-14T23:59:59.000Z

105

Nano-optics with single quantum systems  

Science Journals Connector (OSTI)

...April 2004 research-article Theme Issue Nano-optics and near-field microscopy compiled by David Richards and Anatoly Zayats Nano-optics with single quantum systems This...fluorescent molecules, as local probes for nano-optical field distributions. We start...

2004-01-01T23:59:59.000Z

106

Ultrafast supercontinuum fiber-laser based pump-probe scanning magneto-optical Kerr effect microscope for the investigation of electron spin dynamics in semiconductors at cryogenic temperatures with picosecond time and micrometer spatial resolution  

SciTech Connect (OSTI)

We describe a two-color pump-probe scanning magneto-optical Kerr effect microscope which we have developed to investigate electron spin phenomena in semiconductors at cryogenic temperatures with picosecond time and micrometer spatial resolution. The key innovation of our microscope is the usage of an ultrafast “white light” supercontinuum fiber-laser source which provides access to the whole visible and near-infrared spectral range. Our Kerr microscope allows for the independent selection of the excitation and detection energy while avoiding the necessity to synchronize the pulse trains of two separate picosecond laser systems. The ability to independently tune the pump and probe wavelength enables the investigation of the influence of excitation energy on the optically induced electron spin dynamics in semiconductors. We demonstrate picosecond real-space imaging of the diffusive expansion of optically excited electron spin packets in a (110) GaAs quantum well sample to illustrate the capabilities of the instrument.

Henn, T.; Kiessling, T., E-mail: tobias.kiessling@physik.uni-wuerzburg.de; Ossau, W.; Molenkamp, L. W. [Physikalisches Institut (EP3), Universität Würzburg, 97074 Würzburg (Germany)] [Physikalisches Institut (EP3), Universität Würzburg, 97074 Würzburg (Germany); Biermann, K.; Santos, P. V. [Paul-Drude-Institut für Festkörperelektronik, 10117 Berlin (Germany)] [Paul-Drude-Institut für Festkörperelektronik, 10117 Berlin (Germany)

2013-12-15T23:59:59.000Z

107

Near-field-enhanced, off-resonant laser sintering of semiconductor particles for additive manufacturing of dispersed Au–ZnO-micro/nano hybrid structures  

Science Journals Connector (OSTI)

Off-resonant near-field enhancement by gold nanoparticles adsorbed on crystalline zinc oxide significantly increases the energy efficiency of infrared laser sintering. In detail, ten different gold mass loads ...

Marcus Lau; Ralf G. Niemann; Mathias Bartsch; William O’Neill…

2014-03-01T23:59:59.000Z

108

Slide27 | OSTI, US Dept of Energy, Office of Scientific and Technical...  

Office of Scientific and Technical Information (OSTI)

ETDEWEB - Bibliographic Citation image of report downloaded (Investigation of optical nanostructures for photovoltaics with near-field scanning microscopy...

109

Optical  

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

Optical Optical fiber-based single-shot picosecond transient absorption spectroscopy Andrew R. Cook a͒ and Yuzhen Shen Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973, USA ͑Received 27 January 2009; accepted 29 May 2009; published online 17 July 2009͒ A new type of single-shot transient absorption apparatus is described based on a bundle of optical fibers. The bundle contains 100 fibers of different lengths, each successively giving ϳ15 ps longer optical delay. Data are collected by imaging light from the exit of the bundle into a sample where it is overlapped with an electron pulse or laser excitation pulse, followed by imaging onto a charge coupled device ͑CCD͒ detector where the intensity of light from each fiber is measured simultaneously. Application to both ultrafast pump-probe spectroscopy and pulse radiolysis is demonstrated. For pulse

110

Optics  

Science Journals Connector (OSTI)

Optical components such as lenses, mirrors and diffraction gratings are widely used in many inspection systems. These include not only those for visual inspection with CCD cameras, but also in areas of distanc...

C. Loughlin

1993-01-01T23:59:59.000Z

111

Salton Sea Geothermal Field, California, as a near-field natural analog of a radioactive waste repository in salt  

SciTech Connect (OSTI)

Since high concentrations of radionuclides and high temperatures are not normally encountered in salt domes or beds, finding an exact geologic analog of expected near-field conditions in a mined nuclear waste repository in salt will be difficult. The Salton Sea Geothermal Field, however, provides an opportunity to investigate the migration and retardation of naturally occurring U, Th, Ra, Cs, Sr and other elements in hot brines which have been moving through clay-rich sedimentary rocks for up to 100,000 years. The more than thirty deep wells drilled in this field to produce steam for electrical generation penetrate sedimentary rocks containing concentrated brines where temperatures reach 365/sup 0/C at only 2 km depth. The brines are primarily Na, K, Ca chlorides with up to 25% of total dissolved solids; they also contain high concentrations of metals such as Fe, Mn, Li, Zn, and Pb. This report describes the geology, geophysics and geochemistry of this system as a prelude to a study of the mobility of naturally occurring radionuclides and radionuclide analogs within it. The aim of this study is to provide data to assist in validating quantitative models of repository behavior and to use in designing and evaluating waste packages and engineered barriers. 128 references, 33 figures, 13 tables.

Elders, W.A.; Cohen, L.H.

1983-11-01T23:59:59.000Z

112

Frequency-Selective Near-Field Radiative Heat Transfer between Photonic Crystal Slabs: A Computational Approach for Arbitrary Geometries and Materials  

E-Print Network [OSTI]

of energy from a hot to a cold body is well known to be enhanced (even exceeding the black- body limit) whenFrequency-Selective Near-Field Radiative Heat Transfer between Photonic Crystal Slabs of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 3 Department

Soljaèiæ, Marin

113

PHaSE | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

scanning probe microscopy, near-field scanning optical microscopy, surface science, neutron diffraction and scattering, density functional theory (DFT), monte carlo (MC),...

114

Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repository--BMT1 of the DECOVALEX III project. Part 1: Conceptualization  

E-Print Network [OSTI]

Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste on the safety of a hypothetical nuclear waste repository at the near-field and are presented in three on the safety of nuclear waste repositories. To achieve the second objective, hypothetical benchmark test

Paris-Sud XI, Université de

115

Spectroscopic ellipsometric modeling of a Bi–Te–Se write layer of an optical data storage device as guided by atomic force microscopy, scanning electron microscopy, and X-ray diffraction  

Science Journals Connector (OSTI)

Abstract Conventional magnetic tape is the most widely used medium for archival data storage. However, data stored on it need to be migrated every ca. 5 years. Recently, optical discs that store information for hundreds, or even more than 1000 years, have been introduced to the market. We recently proposed that technology in these optical discs be used to make an optical tape that would show greater permanence than its magnetic counterpart. Here we provide a detailed optical characterization of a sputtered thin film of bismuth, tellurium, and selenium (BTS) that is a proposed data storage layer for these devices. The methodology described herein should be useful in the future development of related materials. Spectroscopic ellipsometry (SE) data are obtained using interference enhancement, and the modeling of this data is guided by results from atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray reflectivity (XRR). By AFM, ca. 40 nm BTS films show ca. 10 nm roughness. SEM images also suggest considerable roughness in the films and indicate that they are composed of 13.1 ± 5.9 nm grains. XRD confirms that the films are crystalline and predicts a grain size of 17 ± 2 nm. XRD results are consistent with the composition of the films — a mildly oxidized BTS material. Three models of increasing complexity are investigated to explain the SE data. The first model consists of a smooth, homogeneous BTS film. The second model adds a roughness layer to the previous model. The third model also has two layers. The bottom layer is modeled as a mixture of BTS and void using a Bruggeman effective medium approximation. The upper layer is similarly modeled, but with a gradient. The first model was unable to adequately model the SE data. The second model was an improvement — lower MSE (4.4) and good agreement with step height measurements. The third model was even better — very low MSE (2.6) and good agreement with AFM results. The third SE model predicted ca. 90% void at the film surface. XRR modeling of the film agreed well with the predictions from SE. The uniquenesses of the SE models were confirmed.

Hao Wang; Nitesh Madaan; Jacob Bagley; Anubhav Diwan; Yiqun Liu; Robert C. Davis; Barry M. Lunt; Stacey J. Smith; Matthew R. Linford

2014-01-01T23:59:59.000Z

116

Parallel optical nanolithography using nanoscale bowtie aperture array  

E-Print Network [OSTI]

-lithography. Our work employed a frequency-tripled diode-pumped solid state (DPSS) laser ( = 355 nm) and Shipley S1805 photoresist. An interference-based optical alignment system was employed to position the bowtie nano-apertures for near- field optical data storage," Jpn. J. Appl. Phys. 41(Part 1, No. 3B), 1632

Xu, Xianfan

117

Transmission Electron Microscope and Scanning Electron Microscopes -  

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

Facilities > Transmission Electron Facilities > Transmission Electron Microscope and Scanning Electron Microscopes FACILITIES Transmission Electron Microscope and Scanning Electron Microscopes Overview Other Facilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Transmission Electron Microscope and Scanning Electron Microscopes The research activities of the Corrosion and Mechanics of Materials Section are supported by complete metallography/sample preparation rooms equipped with several optical and electron microscopes: a Transmission Electron Microscope and two Scanning Electron Microscopes. Bookmark and Share Transmission electron microscope (TEM) Detail of JEOL 100CXII TEM Figure 1: Detail of JEOL 100CXII TEM. Click on image to view larger image.

118

Surface skeleton generation based on 360-degree profile scan  

E-Print Network [OSTI]

A rapid prototyping method is invented, which works on a specific data structure produced by an optical metrology technique: 360-degree surface profile scanning. A computer algorithm takes an object profile data, restructure ...

Chen, Lujie

119

A High shear stress segment along the San Andreas Fault: Inferences based on near-field stress direction and stress magnitude observations in the Carrizo Plain Area  

SciTech Connect (OSTI)

Nearly 200 new in-situ determinations of stress directions and stress magnitudes near the Carrizo plain segment of the San Andreas fault indicate a marked change in stress state occurring within 20 km of this principal transform plate boundary. A natural consequence of this stress transition is that if the observed near-field ``fault-oblique`` stress directions are representative of the fault stress state, the Mohr-Coulomb shear stresses resolved on San Andreas sub-parallel planes are substantially greater than previously inferred based on fault-normal compression. Although the directional stress data and near-hydrostatic pore pressures, which exist within 15 km of the fault, support a high shear stress environment near the fault, appealing to elevated pore pressures in the fault zone (Byerlee-Rice Model) merely enhances the likelihood of shear failure. These near-field stress observations raise important questions regarding what previous stress observations have actually been measuring. The ``fault-normal`` stress direction measured out to 70 km from the fault can be interpreted as representing a comparable depth average shear strength of the principal plate boundary. Stress measurements closer to the fault reflect a shallower depth-average representation of the fault zone shear strength. If this is true, only stress observations at fault distances comparable to the seismogenic depth will be representative of the fault zone shear strength. This is consistent with results from dislocation monitoring where there is pronounced shear stress accumulation out to 20 km of the fault as a result of aseismic slip within the lower crust loading the upper locked section. Beyond about 20 km, the shear stress resolved on San Andreas fault-parallel planes becomes negligible. 65 refs., 15 figs.

Castillo, D. A., [Department of Geology and Geophysics, University of Adelaide (Australia); Younker, L.W. [Lawrence Livermore National Lab., CA (United States)

1997-01-30T23:59:59.000Z

120

Adaptive optics enhanced simultaneous en-face optical coherence tomography  

E-Print Network [OSTI]

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

Dainty, Chris

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

E-Print Network 3.0 - absorption spectroscopic microscopy Sample...  

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

version of scanning near-field optical microscopy (SNOM). The tunable infrared radiation... the l 3.5 mm, CH vibrational stretch mode absorption band. ... Source:...

122

Plasmon-Induced Optical Field Enhancement studied by Correlated...  

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

Plasmon-Induced Optical Field Enhancement studied by Correlated Scanning and Photoemission Electron Microscopy. Plasmon-Induced Optical Field Enhancement studied by Correlated...

123

High-speed noncontact profiler based on scanning white-light interferometry  

Science Journals Connector (OSTI)

We describe a system for fast three-dimensional profilometry, of both optically smooth and optically rough surfaces, based on scanning white-light techniques. The system utilizes an...

Deck, Leslie; de Groot, Peter

1994-01-01T23:59:59.000Z

124

High throughput optical scanner  

DOE Patents [OSTI]

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.

Basiji, David A. (Seattle, WA); van den Engh, Gerrit J. (Seattle, WA)

2001-01-01T23:59:59.000Z

125

Peer Review of "Analysis and Simulation of Near-Field Wave Motion Data from the Source Physics Experiment Explosions," Antoun, et al, 2011 Monitoring Research Review  

SciTech Connect (OSTI)

The following is primarily a review of 'Analysis and Simulation of Near-Field Wave Motion Data from the Source Physics Experiment Explosions,' Antoun, et al, published by Lawrence Livermore National Laboratory (LLNL) after SPE-1 in 2011 (Ref. 1). However, LLNL analysis of SPE-2 (Ref. 2) will also be discussed. A review by Los Alamos National Laboratory (LANL) personnel of Reference 1 finds both the evidence of the effects of joints on the data and the correlation of calculations with the data weak. This conclusion is made on three separate levels: (1) Fundamental observations made of the various referenced figures taken as presented; (2) Observations made following corrections to errors and omissions to the selected data; and (3) Observations made after considering likely errors in the raw data set. The evidence presented in the referenced papers relies on subjective interpretation of various figures. This is the nature of this technical field of study and, indeed, much of our observation is also subjective.

Steedman, David W. [Los Alamos National Laboratory

2012-06-19T23:59:59.000Z

126

Nano-scale optical and electrical probes of materials and processes.  

SciTech Connect (OSTI)

This report describes the investigations and milestones of the Nano-Scale Optical and Electrical Probes of Materials and Processes Junior/Senior LDRD. The goal of this LDRD was to improve our understanding of radiative and non-radiative mechanisms at the nanometer scale with the aim of increasing LED and solar cell efficiencies. These non-radiative mechanisms were investigated using a unique combination of optical and scanning-probe microscopy methods for surface, materials, and device evaluation. For this research we utilized our new near-field scanning optical microscope (NSOM) system to aid in understanding of defect-related emission issues for GaN-based materials. We observed micrometer-scale variations in photoluminescence (PL) intensity for GaN films grown on Cantilever Epitaxy pattern substrates, with lower PL intensity observed in regions with higher dislocation densities. By adding electrical probes to the NSOM system, the photocurrent and surface morphology could be measured concurrently. Using this capability we observed reduced emission in InGaN MQW LEDs near hillock-shaped material defects. In spatially- and spectrally-resolved PL studies, the emission intensity and measured wavelength varied across the wafer, suggesting the possibility of indium segregation within the InGaN quantum wells. Blue-shifting of the InGaN MQW wavelength due to thinning of quantum wells was also observed on top of large-scale ({micro}m) defect structures in GaN. As a direct result of this program, we have expanded the awareness of our new NSOM/multifunctional SPM capability at Sandia and formed several collaborations within Sandia and with NINE Universities. Possible future investigations with these new collaborators might include GaN-based compound semiconductors for green LEDs, nanoscale materials science, and nanostructures, novel application of polymers for OLEDs, and phase imprint lithography for large area 3D nanostructures.

Bogart, Katherine Huderle Andersen

2007-03-01T23:59:59.000Z

127

Vector generator scan converter  

DOE Patents [OSTI]

High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

Moore, J.M.; Leighton, J.F.

1988-02-05T23:59:59.000Z

128

Solid state optical microscope  

DOE Patents [OSTI]

A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal. 2 figs.

Young, I.T.

1983-08-09T23:59:59.000Z

129

Solid state optical microscope  

DOE Patents [OSTI]

A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

Young, Ian T. (Pleasanton, CA)

1983-01-01T23:59:59.000Z

130

Only critical information was scanned  

Office of Legacy Management (LM)

Only critical information was scanned. Entire document is available upon request - Click here to email a...

131

Scanning micro-sclerometer  

DOE Patents [OSTI]

A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch.

Oliver, Warren C. (Knoxville, TN); Blau, Peter J. (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

132

Scanning micro-sclerometer  

DOE Patents [OSTI]

A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch. 2 figs.

Oliver, W.C.; Blau, P.J.

1994-11-01T23:59:59.000Z

133

Microbial Impacts to the Near-Field Environment Geochemistry (MING): A Model for Estimating Microbial Communities in Repository Drifts at Yucca Mountain  

SciTech Connect (OSTI)

Geochemical and microbiological modeling was performed to evaluate the potential quantities and impact of microorganisms on the geochemistry of the area adjacent to and within nuclear waste packages in the proposed repository drifts at Yucca Mountain, Nevada. The microbial growth results from the introduction of water, ground support, and waste package materials into the deep unsaturated rock. The simulations, which spanned one million years, were accomplished using a newly developed computer code, Microbial Impacts to the Near-Field Environment Geochemistry (MING). MING uses environmental thresholds for limiting microbial growth to temperatures below 120 C and above relative humidities of 90 percent in repository drifts. Once these thresholds are met, MING expands upon a mass balance and thermodynamic approach proposed by McKinley and others (1997), by using kinetic rates to supply constituents from design materials and constituent fluxes including solubilized rock components into the drift, to perform two separate mass-balance calculations as a function of time. The first (nutrient limit) assesses the available nutrients (C, N, P and S) and calculates how many microorganisms can be produced based on a microorganism stoichiometry of C{sub 160}(H{sub 280}O{sub 80})N{sub 30}P{sub 2}S. The second (energy limit) calculates the energy available from optimally combined redox couples for the temperature, and pH at that time. This optimization maximizes those reactions that produce > 15kJ/mol (limit on useable energy) using an iterative linear optimization technique. The final available energy value is converted to microbial mass at a rate of 1 kg of biomass (dry weight) for every 64 MJ of energy. These two values (nutrient limit and energy limit) are then compared and the smaller value represents the number of microorganisms that can be produced over a specified time. MING can also be adapted to investigate other problems of interest as the model can be used in saturated and unsaturated environments and in laboratory situations to establish microbial growth limitations. Other projected uses include investigations of contaminated locations where monitored natural attenuation or engineered bioremediation could be employed.

D.M. Jolley; T.F. Ehrhorn; J. Horn

2002-03-19T23:59:59.000Z

134

Optical interferometry at ultra low temperatures  

Science Journals Connector (OSTI)

We have developed optical, interferometric methods for investigations of interfaces at ultra low temperatures. In our scheme conventional optical...3He down to 0.6 mK whereas a slow-scan camera has been...?6). Th...

P. J. Hakonen; H. Alles; A. V. Babkin; J. P. Ruutu

1995-10-01T23:59:59.000Z

135

Free motion scanning system  

DOE Patents [OSTI]

The present invention relates to an ultrasonic scanner system and method for the imaging of a part system, the scanner comprising: a probe assembly spaced apart from the surface of the part including at least two tracking signals for emitting radiation and a transmitter for emitting ultrasonic waves onto a surface in order to induce at least a portion of the waves to be reflected from the part, at least one detector for receiving the radiation wherein the detector is positioned to receive the radiation from the tracking signals, an analyzer for recognizing a three-dimensional location of the tracking signals based on the emitted radiation, a differential converter for generating an output signal representative of the waveform of the reflected waves, and a device such as a computer for relating said tracking signal location with the output signal and projecting an image of the resulting data. The scanner and method are particularly useful to acquire ultrasonic inspection data by scanning the probe over a complex part surface in an arbitrary scanning pattern.

Sword, Charles K. (Pleasant Hills, PA)

2000-01-01T23:59:59.000Z

136

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

SciTech Connect (OSTI)

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.

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

2013-08-06T23:59:59.000Z

137

Rapid scanning mass spectrometer  

SciTech Connect (OSTI)

Mass spectrometers and residual gas analyzers (RGA) are used in a variety of applications for analysis of volatile and semi-volatile materials. Analysis is performed by detecting fragments of gas molecules, based on their mass to charge ratio, which are generated in the mass spectrometer. When used as a detector for a gas chromatograph, they function as a means to quantitatively identify isolated volatile species which have been separated from other species via the gas chromatograph. Vacuum Technology, Inc., (VTI) produces a magnetic sector mass spectrometer/RGA which is used in many industrial and laboratory environments. In order to increase the utility of this instrument, it is desirable to increase the mass scanning speed, thereby increasing the number of applications for which it is suited. This project performed the following three upgrades on the computer interface. (1) A new electrometer was designed and built to process the signal from the detector. This new electrometer is more sensitive, over 10 times faster, and over 100 times more stable than the electrometer it will replace. (2) The controller EPROM was reprogrammed with new firmware. This firmware acts as an operating system for the interface and is used to shuttle communications between the PC and the AEROVAC mass spectrometer. (3) The voltage regulator which causes the ion selector voltage to ramp to allow ions of selected mass to be sequentially detected was redesigned and prototyped. The redesigned voltage regulator can be ramped up or down more than 100 times faster than the existing regulator. These changes were incorporated into a prototype unit and preliminary performance testing conducted. Results indicated that scanning speed was significantly increased over the unmodified version.

Leckey, J.H. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Boeckmann, M.D. [Vacuum Technology, Inc., Oak Ridge, TN (United States)

1996-11-25T23:59:59.000Z

138

Laser scanning third-harmonic-generation microscopy in biology  

E-Print Network [OSTI]

. Denk, J. H. Stricker and W. W. Webb, "Two-photon laser scanning fluorescence microscopy," Science 248, 73-76 (1990). 3. S. Maiti, J. B. Shear, R. M. Williams, W. R. Zipfel and W. W. Webb, "Measuring-214 (1996). 6. R. Hellwarth and P. Christensen, "Nonlinear optical microscopic examination of structure

Silberberg, Yaron

139

Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons  

E-Print Network [OSTI]

Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons ABSTRACT A video-rate (30 frames/s) scanning two-photon excitation microscope has been successfully tested 690 to 1050 nm, prechirper optics for laser pulse-width compression, resonant galvanometer for video

Tsien, Roger Y.

140

Fast Image Drift Compensation in Scanning Electron Microscope Using Image Registration  

E-Print Network [OSTI]

Fast Image Drift Compensation in Scanning Electron Microscope Using Image Registration Naresh Marturi, Sounkalo Demb´el´e and Nadine Piat Abstract-- Scanning Electron Microscope (SEM) image ac analysis and characterization of materials to recover their structural, mechanical, electrical and optical

Boyer, Edmond

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Switchable stiffness scanning microscope probe  

E-Print Network [OSTI]

Atomic Force Microscopy (AFM) has rapidly gained widespread utilization as an imaging device and micro/nano-manipulator during recent years. This thesis investigates the new concept of a dual stiffness scanning probe with ...

Mueller-Falcke, Clemens T. (Clemens Tobias)

2005-01-01T23:59:59.000Z

142

Preparation, optical and non-linear optical power limiting properties of Cu, CuNi nanowires  

SciTech Connect (OSTI)

Metallic nanowires show excellent Plasmon absorption which is tunable based on its aspect ratio and alloying nature. We prepared Cu and CuNi metallic nanowires and studied its optical and nonlinear optical behavior. Optical properties of nanowires are theoretically explained using Gans theory. Nonlinear optical behavior is studied using a single beam open aperture z-scan method with the use of 5?ns Nd: YAG laser. Optical limiting is found to arise from two-photon absorption.

Udayabhaskar, R.; Karthikeyan, B., E-mail: bkarthik@nitt.edu [Department of Physics, National Institute of Technology, Tiruchirappalli 620 015 (India); Ollakkan, Muhamed Shafi [Light and Matter Physics Group, Raman Research Institute, Bangalore 560 080 (India)] [Light and Matter Physics Group, Raman Research Institute, Bangalore 560 080 (India)

2014-01-06T23:59:59.000Z

143

Partial scan design and test sequence generation based on reduced scan shift method  

Science Journals Connector (OSTI)

This paper presents a partial scan algorithm, calledPARES (PartialscanAlgorithm based onREduced Scan shift), for designing partial scan circuits. PARES is based on the reduced scan shift that has been previously ...

Yoshinobu Higami; Seiji Kajihara; Kozo Kinoshita

144

Time-varying spectra through optical diffraction scanning  

Science Journals Connector (OSTI)

...Physical Principles of the Quantum Theory, University of Chicago...slit. The microscope is on a motor-driven platform which can...as an initial condition in future calcula- %ions, as explained...Physical Principles of the Quantum Theory, University of Chicago...

Philip L. Jackson

145

Scan  

Broader source: Energy.gov (indexed) [DOE]

NAME OF PERSON WITH WHOM TO CONFER TELEPHONE DATE ARCHIVIST OF THE UNITED STATES Sharon Evelin NUMBER 1 301 -903-3455 i 1 - I REQUEST FOR REe?RDS DISPOSITION AUTHORITY NUMBER /dl- Y s + - o + - / TO: NATIONAL ARCH~VES & RECORDS ADMINISTRATION 8601 ADELPHI ROAD COLLEGE PARK, MD 20740-6001 1. FROM (Agency or establ~shment) U.S. DEPARTMENT OF ENERGY MAJOR SUBDIVISION Office of the Chief Information Officer MINOR SUBDIVISION Records Management Division I 1 8. DESCRIPTION OF ITEM AND PROPOSED DISPOSITION 1 9. GRS OR 1 10. A ~ T I O r Date received I Z L U V - ~ NOTIFICATION TO AGENCY In accordance with the provlslons of 44 U.S.C 3303a, the dlsposltlon request, Including amendments, 1 s approved except for Items that may be marked "dlsposltion not approved" or "withdrawn" In column 10.

146

Solid-state optical microscope  

DOE Patents [OSTI]

A solid state optical microscope is described wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. Means for scanning in one of two orthogonal directions are provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

Young, I.T.

1981-01-07T23:59:59.000Z

147

Optical Fibers Optics and Photonics  

E-Print Network [OSTI]

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

Palffy-Muhoray, Peter

148

katherine henderson Pathology Slide Scanning rev1 Page 1 10/21/14 Scanning in Pathology  

E-Print Network [OSTI]

katherine henderson Pathology Slide Scanning rev1 Page 1 10/21/14 Scanning in Pathology Pathology offers several scanning methods: · Whole slide scans to be used as virtual microscopy ­ Aperio Coolscan for 35mm slides or glass slides with adapter (scans tissue area, not cells) The above scanners

149

ARM: W-Band Scanning ARM Cloud Radar (W-SACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

W-Band Scanning ARM Cloud Radar (W-SACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

Widener, Kevin; Nelson, Dan; Bharadwaj, Nitin; Lindenmaier, Iosif [Andrei; Johnson, Karen

150

ARM: Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan (6 horizon-to-horizon scans at 30-degree azimuth intervals)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan (6 horizon-to-horizon scans at 30-degree azimuth intervals)

Bharadwaj, Nitin; Widener, Kevin

151

ARM: X-Band Scanning ARM Cloud Radar (XSACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

X-Band Scanning ARM Cloud Radar (XSACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

Widener, Kevin; Nelson, Dan; Bharadwaj, Nitin; Lindenmaier, Iosif [Andrei; Johnson, Karen

152

NASA DC-8 Airborne Scanning Lidar System  

Science Journals Connector (OSTI)

A scanning lidar system is being developed for installation on the NASA DC-8 atmospheric research aircraft to support...in-situ aerosol and gas measurements. Design and objectives of the DC-8 scanning lidar are p...

Norman B. Nielsen; Edward E. Uthe…

1997-01-01T23:59:59.000Z

153

Three-dimensional scanning confocal laser microscope  

DOE Patents [OSTI]

A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

Anderson, R. Rox (Lexington, MA); Webb, Robert H. (Lincoln, MA); Rajadhyaksha, Milind (Charlestown, MA)

1999-01-01T23:59:59.000Z

154

Scan Energy AS | Open Energy Information  

Open Energy Info (EERE)

Scan Energy AS Jump to: navigation, search Name: Scan Energy AS Place: Dybvad, Denmark Zip: DK-9352 Sector: Solar, Wind energy Product: Denmark-based solar and wind power project...

155

Argonne CNM Highlight: Light Scattering by Nanoparticles  

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

Light Scattering by Nanoparticles: Understanding Confinement of Light for Nanophotonics Applications through Near-Field Scanning Optical Microscopy Light Scattering by Nanoparticles: Understanding Confinement of Light for Nanophotonics Applications through Near-Field Scanning Optical Microscopy Schematic of the apertureless near-field optical microscope Schematic of the apertureless near-field optical microscope. The optical scattering from the AFM probe tip provides the subdiffraction-limited optical field information. One of the motivations of nanoscience is to achieve sufficient control over photon propagation in nanostructures so as to effectively replace the electron with the photon in all-optical integrated circuits. The much greater speed and bandwidth of light pulses versus electrons promise new capabilities and size reduction of photon based “electronics.” Arrays of metal nanoparticles are currently considered a leading candidate for photon

156

In situ laser processing in a scanning electron microscope  

SciTech Connect (OSTI)

Laser delivery probes using multimode fiber optic delivery and bulk focusing optics have been constructed and used for performing materials processing experiments within scanning electron microscope/focused ion beam instruments. Controlling the current driving a 915-nm semiconductor diode laser module enables continuous or pulsed operation down to sub-microsecond durations, and with spot sizes on the order of 50 {micro}m diameter, achieving irradiances at a sample surface exceeding 1 MW/cm{sup 2}. Localized laser heating has been used to demonstrate laser chemical vapor deposition of Pt, surface melting of silicon, enhanced purity, and resistivity via laser annealing of Au deposits formed by electron beam induced deposition, and in situ secondary electron imaging of laser induced dewetting of Au metal films on SiO{sub x}.

Roberts, Nicholas [University of Tennessee, Knoxville (UTK); Fowlkes, Jason Davidson [ORNL; Rack, Prof. Philip [University of Tennessee, Knoxville (UTK); Moore, Tom [OmniProbe, Inc.; Magel, Greg [OmniProbe, Inc.; Hartfield, Cheryl [OmniProbe, Inc.

2012-01-01T23:59:59.000Z

157

In situ laser processing in a scanning electron microscope  

SciTech Connect (OSTI)

Laser delivery probes using multimode fiber optic delivery and bulk focusing optics have been constructed and used for performing materials processing experiments within scanning electron microscope/focused ion beam instruments. Controlling the current driving a 915-nm semiconductor diode laser module enables continuous or pulsed operation down to sub-microsecond durations, and with spot sizes on the order of 50 {mu}m diameter, achieving irradiances at a sample surface exceeding 1 MW/cm{sup 2}. Localized laser heating has been used to demonstrate laser chemical vapor deposition of Pt, surface melting of silicon, enhanced purity, and resistivity via laser annealing of Au deposits formed by electron beam induced deposition, and in situ secondary electron imaging of laser induced dewetting of Au metal films on SiO{sub x}.

Roberts, Nicholas A.; Magel, Gregory A.; Hartfield, Cheryl D.; Moore, Thomas M.; Fowlkes, Jason D.; Rack, Philip D. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States) and Omniprobe, Inc., an Oxford Instruments Company, 10410 Miller Rd., Dallas, Texas 75238 (United States); Omniprobe, Inc., an Oxford Instruments Company, 10410 Miller Rd., Dallas, Texas 75238 (United States); Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States) and Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2012-07-15T23:59:59.000Z

158

OPTICS5  

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

Optics5 (5.1.02) Knowledge Base Optics5 (5.1.02) Knowledge Base Last Updated: 09/11/13 Table of Contents INSTALLATION EXECUTION bullet ** Operating Systems -- Microsoft Windows 7 and Vista ** bullet ** Running Optics5 with Microsoft Windows 7 and Vista ** bullet ** Running Optics5 with Microsoft Windows 7 and Vista 64 bit ** Optics5 may not work correctly with regional/locale settings using "," as a decimal separator. bullet Which Windows operating systems can be used to run Optics? "Class Does Not Support Automation or Expected Interface" error message bullet How much hard disk space should be available to install Optics? Optics user manual bullet I receive a virus warning (nimda-virus) when installing Optics. What should I do? NFRC Procedure for Applied Films bullet I have installed Optics but I can't find the program or the icon.

159

Developing new optical imaging techniques for single particle and molecule tracking in live cells  

SciTech Connect (OSTI)

Differential interference contrast (DIC) microscopy is a far-field as well as wide-field optical imaging technique. Since it is non-invasive and requires no sample staining, DIC microscopy is suitable for tracking the motion of target molecules in live cells without interfering their functions. In addition, high numerical aperture objectives and condensers can be used in DIC microscopy. The depth of focus of DIC is shallow, which gives DIC much better optical sectioning ability than those of phase contrast and dark field microscopies. In this work, DIC was utilized to study dynamic biological processes including endocytosis and intracellular transport in live cells. The suitability of DIC microscopy for single particle tracking in live cells was first demonstrated by using DIC to monitor the entire endocytosis process of one mesoporous silica nanoparticle (MSN) into a live mammalian cell. By taking advantage of the optical sectioning ability of DIC, we recorded the depth profile of the MSN during the endocytosis process. The shape change around the nanoparticle due to the formation of a vesicle was also captured. DIC microscopy was further modified that the sample can be illuminated and imaged at two wavelengths simultaneously. By using the new technique, noble metal nanoparticles with different shapes and sizes were selectively imaged. Among all the examined metal nanoparticles, gold nanoparticles in rod shapes were found to be especially useful. Due to their anisotropic optical properties, gold nanorods showed as diffraction-limited spots with disproportionate bright and dark parts that are strongly dependent on their orientation in the 3D space. Gold nanorods were developed as orientation nanoprobes and were successfully used to report the self-rotation of gliding microtubules on kinesin coated substrates. Gold nanorods were further used to study the rotational motions of cargoes during the endocytosis and intracellular transport processes in live mammalian cells. New rotational information was obtained: (1) during endocytosis, cargoes lost their rotation freedom at the late stage of internalization; (2) cargoes performed train-like motion when they were transported along the microtubule network by motor proteins inside live cells; (3) During the pause stage of fast axonal transport, cargoes were still bound to the microtubule tracks by motor proteins. Total internal reflection fluorescence microscopy (TIRFM) is another non-invasive and far-field optical imaging technique. Because of its near-field illumination mechanism, TIRFM has better axial resolution than epi-fluorescence microscopy and confocal microscopy. In this work, an auto-calibrated, prism type, angle-scanning TIRFM instrument was built. The incident angle can range from subcritical angles to nearly 90{sup o}, with an angle interval less than 0.2{sup o}. The angle precision of the new instrument was demonstrated through the finding of the surface plasmon resonance (SPR) angle of metal film coated glass slide. The new instrument improved significantly the precision in determining the axial position. As a result, the best obtained axial resolution was {approx} 8 nm, which is better than current existing instruments similar in function. The instrument was further modified to function as a pseudo TIRF microscope. The illumination depth can be controlled by changing the incident angle of the excitation laser beam or adjusting the horizontal position of the illumination laser spot on the prism top surface. With the new technique, i.e., variable-illumination-depth pseudo TIRF microscopy, the whole cell body from bottom to top was scanned.

Sun, Wei

2010-12-15T23:59:59.000Z

160

Imaging - Clearer brain scans ... | ornl.gov  

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

Imaging - Clearer brain scans ... A clever signal noise reduction strategy developed by a team that includes Oak Ridge National Laboratory's Ben Lawrie could dramatically improve...

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Differential Scanning Microcalorimetry of Intrinsically Disordered Proteins  

Science Journals Connector (OSTI)

Ultrasensitive differential scanning calorimetry (DSC) is an indispensable thermophysical technique enabling to get direct information on enthalpies accompanying heating/cooling of dilute biopolymer solutions. Th...

Sergei E. Permyakov

2012-01-01T23:59:59.000Z

162

Nonimaging Optics  

Science Journals Connector (OSTI)

The nonimaging optical system, by definition, does not produce an image of the light source. Instead, it is designed to concentrate radiation at a density as high as theoretically possible. Nonimaging optics h...

Dr. Ralf Leutz; Dr. Akio Suzuki

2001-01-01T23:59:59.000Z

163

Optical Switch  

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

seven wonders Optical Switch A key component in the laser chain, an optical switch called a plasma electrode Pockels cell (PEPC), was invented and developed at LLNL. A Pockels cell...

164

City of College Station's Thermographic Mobile Scan  

E-Print Network [OSTI]

During the first quarter of 1986, the City of College Station conducted a thermographic mobile scan of the entire city. A thermographic mobile scan is a process by which heat loss/heat gain data is accumulated by a vehicle traveling the city...

Shear, C. K.

1986-01-01T23:59:59.000Z

165

Spring Semester, Course Title: Scanned Probe Techniques  

E-Print Network [OSTI]

: a fundamental understanding of the theoretical underpinnings behind each scanned probe technique Probe Microscopy: Atomic Scale Engineering by Forces and Currents - Adam Foster and Werner Hofer Applied Scanning Probe Methods (Vol. 1-13) ­ Bharat Bhushan, ed. Springer Handbook of Nanotechnology - Bharat

Sherrill, David

166

The Scanning Theremin Microscope: A Model Scanning Probe Instrument for Hands-On Activities  

Science Journals Connector (OSTI)

(9, 10) However, we decided upon a different approach and worked with scanning probe principles to create a large-scale scanning device, the scanning theremin microscope (SThM). ... The simplest mode of scanning is to move the pantograph to scan the probe across the surface at a fixed height, listening for changes in pitch. ... We present a cascade-based computation scheme that has all of the devices and interconnects required for the one-time computation of an arbitrary logic function. ...

Rebecca C. Quardokus; Natalie A. Wasio; S. Alex Kandel

2013-12-20T23:59:59.000Z

167

Fast scanning two-photon microscopy  

E-Print Network [OSTI]

Fast scanning two-photon microscopy coupled with the use light activated ion channels provides the basis for fast imaging and stimulation in the characterization of in vivo neural networks. A two-photon microscope capable ...

Chang, Jeremy T

2010-01-01T23:59:59.000Z

168

Variable Temperature Scanning Probe Microscope | EMSL  

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

EMSL's ultra-high vacuum, variable-temperature scanning probe microscope system, or UHV VT SPM, is a state-of-the-art surface science tool comprising multiple complementary...

169

String Scanning in the Icon Programming Language  

Science Journals Connector (OSTI)

...Article String Scanning in the Icon Programming Language R. E. Griswold * Department of Computer Science, The University...general-purpose programming language and describes how they have been introduced in the Icon programming language....

R. E. Griswold

1990-01-01T23:59:59.000Z

170

OPTICS 5  

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

OPTICS (Version 5.1.02) OPTICS (Version 5.1.02) Release notes NOTE: See the Optics Knowledge Base for how to run this version of Optics on the Microsoft Vista and Microsoft Windows 7 operating systems March 5, 2003: Release Maintenance Pack 2 New ! January 7, 2003: Release Maintenance Pack 1 October 23, 2002: Release Optics 5.1.01 September 27, 2002: Release Optics 5.1.00 (only released on CDs at NFRC Annual Fall Meeting) Release notes Maintenance Pack 2 Bug fixes: New features: bullet Applied films that were created could not be saved or exported. This has been fixed. bullet Exporting glazing systems generated a message that the operation failed because the glazing system type is unknown. Glazing systems can now be exported to file (e.g. to view the spectral data), but the structure information will be lost.

171

A new scanning photoemission microscope for ELETTRA: SuperMAXIMUM  

Science Journals Connector (OSTI)

High brightness third?generation synchrotrons allow diffraction?limited performance and large flux for scanning photoemission microscopes. A new microscope SuperMAXIMUM is being developed at the University of Wisconsin Center for X ray Lithography in collaboration with the Sincrotrone Trieste. The beamline being built in Trieste uses a variable angle spherical gratingmonochromator (VASGM). A combination of rotation of a plane mirror and rotation of the spherical grating keeps the slit positions and beam directions fixed. The microscope objectives are normal?incidence multilayer?coated Schwarzschild objectives. The project which is nearing completion utilizes novel designs for optics alignment sample rastering mechanics and software control. We will discuss the project status new designs and techniques.

John T. Welnak; H. Solak; J. Wallace; F. Cerrina; F. Barbo; M. Bertolo; A. Bianco; S. Di Fonzo; S. Fontana; W. Jark; F. Mazzolini; R. Rosei; A. Savoia; J.H. Underwood; G. Margaritondo

1996-01-01T23:59:59.000Z

172

A new scanning photoemission microscope for ELETTRA: SuperMAXIMUM  

SciTech Connect (OSTI)

High brightness, third-generation synchrotrons allow diffraction-limited performance and large flux for scanning photoemission microscopes. A new microscope, SuperMAXIMUM, is being developed at the University of Wisconsin Center for X ray Lithography in collaboration with the Sincrotrone Trieste. The beamline, being built in Trieste, uses a variable angle spherical grating monochromator (VASGM). A combination of rotation of a plane mirror and rotation of the spherical grating keeps the slit positions and beam directions fixed. The microscope objectives are normal-incidence, multilayer-coated Schwarzschild objectives. The project, which is nearing completion, utilizes novel designs for optics alignment, sample rastering mechanics, and software control. We will discuss the project status, new designs, and techniques. {copyright} {ital 1996 American Institute of Physics.}

Welnak, J.T.; Solak, H.; Wallace, J.; Cerrina, F.; Barbo, F.; Bertolo, M.; Bianco, A.; Di Fonzo, S.; Fontana, S.; Jark, W.; Mazzolini, F.; Rosei, R.; Savoia, A.; Underwood, J.; Margaritondo, G. [University of WI--Center for X ray Lithography, 3731 Schneider Drive, Stoughton, WI 53589 (United States)] [University of WI--Center for X ray Lithography, 3731 Schneider Drive, Stoughton, WI 53589 (United States); [Sincrotrone Trieste, Padriciano 99, 34012, Trieste (Italy); [Lawrence Berkeley Laboratory, Center for X ray Optics, 1 Cyclotron Road, 80-101, Berkeley, CA 94720 (United States); [Institut de Physique Appliqee, Ecole Polytechnique Federale, CH-1015, Lausanne (Switzerland)

1996-09-01T23:59:59.000Z

173

Optical Magnetism  

Science Journals Connector (OSTI)

Magnetic dipole radiation one fourth as intense as electric dipole radiation, as well as a novel nonlinear magneto-optical effect are reported in dielectric media.

Oliveira, Samuel L; Rand, Stephen C

174

A simple scanning spectrometer based on a stretchable elastomeric reflective grating  

SciTech Connect (OSTI)

We report a scanning optical spectrometer based on the use of a stretchable elastomeric reflective grating. The grating is obtained by supersonic cluster beam implantation of silver nanoparticles on polydimethylsiloxane previously grooved by molding to create a replica of a commercial digital versatile disk grating. The use of a stretchable grating allows the spectrometer spanning the whole optical wavelength range by solely extending the diffraction element by more than 100% of its original dimensions. The stretchable reflective optical grating shows excellent performances and stability upon thousands of stretching cycles. The use of this elastomeric element makes the optical layout and the mechanics of the spectrometer extremely simple and advantageous for those applications where spectral resolution is not a major requirement. As a proof of principle, we present the absorption spectrum of Rhodamine B in solution obtained by our spectrometer and compared to commercial instruments.

Ghisleri, C.; Milani, P., E-mail: paolo.milani@mi.infn.it [CIMAINA and Dipartimento di Fisica, Università di Milano, via Celoria 16, 20133 Milano (Italy); WISE srl, Piazza Duse 2, 20122 Milano (Italy); Potenza, M. A. C.; Bellacicca, A. [CIMAINA and Dipartimento di Fisica, Università di Milano, via Celoria 16, 20133 Milano (Italy); Ravagnan, L. [WISE srl, Piazza Duse 2, 20122 Milano (Italy)

2014-02-10T23:59:59.000Z

175

Optical Expanders with Applications in Optical Computing  

E-Print Network [OSTI]

Optical Expanders with Applications in Optical Computing John H. Reif Akitoshi Yoshida July 20, 1999 Abstract We describe and investigate an optical system which we call an optical expander. An optical expander elec- trooptically expands an optical boolean pattern encoded in d bits into an optical

Reif, John H.

176

Optical Glass  

Science Journals Connector (OSTI)

... space of time. In the forefront of such vital industries is the manufacture of optical glass. However great the other resources in men and material may be, it would be ... be, it would be quite impossible to wage successful warfare without adequate supplies of optical glass ior binocular field- ...

1919-03-27T23:59:59.000Z

177

Axial-scanning low-coherence interferometer method for noncontact thickness measurement of biological samples  

SciTech Connect (OSTI)

We investigated a high-precision optical method for measuring the thickness of biological samples regardless of their transparency. The method is based on the precise measurement of optical path length difference of the end surfaces of objects, using a dual-arm axial-scanning low-coherence interferometer. This removes any consideration of the shape, thickness, or transparency of testing objects when performing the measurement. Scanning the reference simplifies the measurement setup, resulting in unambiguous measurement. Using a 1310 nm wavelength superluminescent diode, with a 65 nm bandwidth, the measurement accuracy was as high as 11.6 {mu}m. We tested the method by measuring the thickness of both transparent samples and nontransparent soft biological tissues.

Kim, Do-Hyun; Song, Chul-Gyu; Ilev, Ilko K.; Kang, Jin U.

2011-02-20T23:59:59.000Z

178

Optical characterization of femtosecond laser induced active channel waveguides in lithium fluoride crystals  

SciTech Connect (OSTI)

We successfully realized broad-band light-emitting color center waveguides buried in LiF crystals by using femtosecond laser pulses. The characterization of the waveguides was performed by optical microscopy, photoluminescence spectra, loss measurements and near-field profiling. The experimental results show that the direct-writing fabrication process induces low-index contrast active channel waveguides: their wavelength-dependent refractive index changes, estimated from 10{sup ?3} to 10{sup ?4} depending on the writing conditions, allow supporting few modes at visible and near-infrared wavelengths.

Chiamenti, I.; Kalinowski, H. J., E-mail: hjkalin@utfpr.edu.br [Federal University of Technology–Paraná, Photonics Laboratory, 80230-901 Curitiba (Brazil); Bonfigli, F.; Montereali, R. M. [ENEA C.R. Frascati, Photonics Micro and Nanostructures Laboratory, V. E. Fermi, 45, 00044 Frascati (RM) (Italy); Gomes, A. S. L. [Universidade Federal de Pernambuco, Department of Physics, 50740-560 Recife (Brazil); Michelotti, F. [Universitá degli Studi di Roma “La Sapienza,” Dipartimento di Scienze di Base e Applicate per l'Ingegneria, Via A. Scarpa, 16, 00161, Rome (Italy)

2014-01-14T23:59:59.000Z

179

High-precision absolute distance and vibration measurement with frequency scanned interferometry  

SciTech Connect (OSTI)

We report high-precision absolute distance and vibration measurements performed with frequency scanned interferometry using a pair of single-mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse Fabry-Perot interferometer was used to determine frequency changes during scanning. Two multiple-distance-measurement analysis techniques were developed to improve distance precision and to extract the amplitude and frequency of vibrations. Under laboratory conditions, measurement precision of {approx}50 nm was achieved for absolute distances ranging from 0.1 to 0.7 m by use of the first multiple-distance-measurement technique. The second analysis technique has the capability to measure vibration frequencies ranging from 0.1 to 100 Hz with an amplitude as small as a few nanometers without a priori knowledge.

Yang, H.-J.; Deibel, Jason; Nyberg, Sven; Riles, Keith

2005-07-01T23:59:59.000Z

180

Variable Temperature Ultra-High Vacuum Scanning Tunneling Microscope...  

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

Vacuum Scanning Tunneling Microscope The Omicron variable temperature ultra-high vacuum (UHV) scanning tunneling microscope (VTSTM) is designed to study the structure of both clean...

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

A New Interpretation of the Scanning Tunneling Microscope Image...  

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

of Graphite. A New Interpretation of the Scanning Tunneling Microscope Image of Graphite. Abstract: In this work, highly-resolved scanning tunneling microscopy images of graphite...

182

H2Scan LLC | Open Energy Information  

Open Energy Info (EERE)

H2Scan LLC H2Scan LLC Jump to: navigation, search Name H2Scan LLC Place Valencia, California Zip 91355 Sector Hydro, Hydrogen Product Hydrogen specific sensing systems, uniquely able to detect hydrogen against virtually any background gases. Coordinates 39.468791°, -0.376913° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":39.468791,"lon":-0.376913,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

183

WorldScan | Open Energy Information  

Open Energy Info (EERE)

WorldScan WorldScan Jump to: navigation, search LEDSGP green logo.png FIND MORE DIA TOOLS This tool is part of the Development Impacts Assessment (DIA) Toolkit from the LEDS Global Partnership. Tool Summary LAUNCH TOOL Name: WorldScan Agency/Company /Organization: Netherlands Bureau for Economic Policy Analysis (CPB) Sector: Climate, Energy Complexity/Ease of Use: Moderate Website: www.gtap.agecon.purdue.edu/resources/res_display.asp?RecordID=1923 Related Tools Marginal Abatement Cost Tool (MACTool) Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) Gold Standard Program Model ... further results A recursively dynamic general equilibrium model for the world economy, developed for the analysis of long-term issues in international economics; used both as a tool to construct long-term scenarios and as an instrument

184

Fiber optic coupled optical sensor  

DOE Patents [OSTI]

A displacement sensor includes a first optical fiber for radiating light to a target, and a second optical fiber for receiving light from the target. The end of the first fiber is adjacent and not axially aligned with the second fiber end. A lens focuses light from the first fiber onto the target and light from the target onto the second fiber.

Fleming, Kevin J. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

185

A compact scanning soft X-ray microscope  

SciTech Connect (OSTI)

Soft x-ray microscopes operating at wavelengths between 2.3 nm and 4.4 nm are capable of imaging wet biological cells with a resolution many times that of a visible light microscope. Several such soft x-ray microscopes have been constructed. However, with the exception of contact microscopes, all use synchrotrons as the source of soft x-ray radiation and Fresnel zone plates as the focusing optics. These synchrotron based microscopes are very successful but have the disadvantage of limited access. This dissertation reviews the construction and performance of a compact scanning soft x-ray microscope whose size and accessibility is comparable to that of an electron microscope. The microscope uses a high-brightness laser-produced plasma as the soft x-ray source and normal incidence multilayer-coated mirrors in a Schwarzschild configuration as the focusing optics. The microscope operates at a wavelength of 14 nm, has a spatial resolution of 0.5 {mu}m, and has a soft x-ray photon flux through the focus of 10{sup 4}-10{sup 5} s{sup {minus}1} when operated with only 170 mW of average laser power. The complete system, including the laser, fits on a single 4{prime} x 8{prime} optical table. The significant components of the compact microscope are the laser-produced plasma (LPP) source, the multilayer coatings, and the Schwarzschild objective. These components are reviewed, both with regard to their particular use in the current microscope and with regard to extending the microscope performance to higher resolution, higher speed, and operation at shorter wavelengths. Measurements of soft x-ray emission and debris emission from our present LPP source are presented and considerations given for an optimal LPP source. The LPP source was also used as a broadband soft x-ray source for measurement of normal incidence multilayer mirror reflectance in the 10-25 nm spectral region.

Trail, J.A.

1989-01-01T23:59:59.000Z

186

Nonlinear optics  

E-Print Network [OSTI]

Nicolaas Bloembergen, recipient of the Nobel Prize for Physics (1981), wrote Nonlinear Optics in 1964, when the field of nonlinear optics was only three years old. The available literature has since grown by at least three orders of magnitude.The vitality of Nonlinear Optics is evident from the still-growing number of scientists and engineers engaged in the study of new nonlinear phenomena and in the development of new nonlinear devices in the field of opto-electronics. This monograph should be helpful in providing a historical introduction and a general background of basic ideas both for expe

Bloembergen, Nicolaas

1996-01-01T23:59:59.000Z

187

Optical Expanders with Applications in Optical Computing  

E-Print Network [OSTI]

Optical Expanders with Applications in Optical Computing John H. Reif \\Lambda Akitoshi Yoshida \\Lambda July 20, 1999 Abstract We describe and investigate an optical system which we call an optical expander. An optical expander elec­ trooptically expands an optical boolean pattern encoded in d bits

Reif, John H.

188

LIVE SCAN FINGERPRINTING PROCESS AND RESPONSIBILITIES  

E-Print Network [OSTI]

LIVE SCAN FINGERPRINTING PROCESS AND RESPONSIBILITIES HUMAN RESOURCES Workforce Planning | One of recruitment) to your Workforce Planning Analyst. Notify Finalists Department must notify finalists of the Live. Workforce Planning Analyst will make available at the Human Resources reception desk, the appropriate number

Eirinaki, Magdalini

189

Department of Health I. Internal Scan  

E-Print Network [OSTI]

and cholesterol; and working with consumers, health plans and providers to improve the quality of care and other non- institutional settings. CURRRENT PLANS: The Division of Health care Financing has been takingDepartment of Health I. Internal Scan There are a variety of areas that will be impacted

Tipple, Brett

190

Student Charter Scan the QR-code  

E-Print Network [OSTI]

Student Charter 2013/2014 Scan the QR-code to obtain the online version. TechnischeUniversiteitDelft #12;#12;Student Charter 2013/2014 Delft University of Technology This is the English version of the Student Charter of Delft University of Technology, published on the TU Delft website: www

191

Scanning Probe Microscopy Studies of Carbon Nanotubes  

E-Print Network [OSTI]

Scanning Probe Microscopy Studies of Carbon Nanotubes Teri Wang Odom1 , Jason H. Hafner1 relationship between Single-Walled Carbon Nanotube (SWNT) atomic structure and electronic properties, (2, properties and application of carbon nanotube probe microscopy tips to ultrahigh resolution and chemically

Odom, Teri W.

192

Global registration of dynamic range scans for articulated model reconstruction  

Science Journals Connector (OSTI)

We present the articulated global registration algorithm to reconstruct articulated 3D models from dynamic range scan sequences. This new algorithm aligns multiple range scans simultaneously to reconstruct a full 3D model from the geometry of these scans. ... Keywords: Range scanning, animation reconstruction, articulated model, nonrigid registration

Will Chang; Matthias Zwicker

2011-05-01T23:59:59.000Z

193

Core stress distribution of phase shifting multimode polymer optical fiber  

SciTech Connect (OSTI)

Poly-(methyl methacrylate-co-benzyl methacrylate) polarization-maintaining optical fibers are known for their high response to normal stress. In this report, responses to higher stress levels up to 0.45?MPa were investigated. The stress amplitude and direction in the fiber cross section were calculated and analyzed with a coincident mode-field obtained from the near-field pattern. The stress amplitude varies significantly in the horizontal direction and is considered to create multiple phases, explaining the measurement results. To investigate possible permanent deformation, the core yield point profile was analyzed. Although it largely exceeds the average applied stress, the calculated stress distribution indicates that the core could partially experience stress that exceeds the yield point.

Furukawa, Rei, E-mail: furukawa@ee.uec.ac.jp; Matsuura, Motoharu [Center for Frontier Science and Engineering, The University of Electro-Communications, Chofugaoka 1-5-1, Chofu, Tokyo 182-8585 (Japan)] [Center for Frontier Science and Engineering, The University of Electro-Communications, Chofugaoka 1-5-1, Chofu, Tokyo 182-8585 (Japan); Nagata, Morio; Mishima, Kenji [Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904 (Japan)] [Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904 (Japan); Inoue, Azusa; Tagaya, Akihiro; Koike, Yasuhiro [Keio Photonics Research Institute, Keio University, Saiwaiku Shinkawasaki 7-1, Kawasaki, Kanagawa 212-0032 (Japan)] [Keio Photonics Research Institute, Keio University, Saiwaiku Shinkawasaki 7-1, Kawasaki, Kanagawa 212-0032 (Japan)

2013-11-18T23:59:59.000Z

194

Development of a combined interference microscope objective and scanning probe microscope  

Science Journals Connector (OSTI)

A compact sensor head combining optical interference and scanning probe microscopy in a single instrument has been developed. This instrument is able to perform complementary quantitative measurements combining fast nondestructive three-dimensional surface analysis with high lateral resolution imaging. A custom interference microscopesensor head has been designed as the optical microscope objective and integrated within the architecture of a commercial interference microscope. The combined instrument makes available both the acquisition software and the hardware interface of the commercial microscope. The latter is able to function as a phase-shift interferometer or white light interferometer. Furthermore the use of an optical fiber to transmit light from an external laser: (i) removes a major heat source from the measurement environment and (ii) makes aperture correction unnecessary. The lateral resolution of the instrument has been extended by the addition of a previously developed compact scanning probe microscope(SPM) module to the custom interference microscope objective. This SPM unit is based upon piezoresistive cantilever technology. The “piezolevers” are self-sensing and therefore require no additional systems such as optical beam deflection or fiber interferometry to monitor their displacement. The mechanical simplicity of the piezolever SPM unit allows for a small physical size and can thus be added to the custom optical sensor head without violating constraints on the working distance defined by the optics. A major benefit of the system in terms of a quantitative nanometrology is the possibility to perform a traceable and direct calibration of the SPM module. This calibration is achieved practically by measuring an appropriate sample at a common location using both techniques. Results are presented here for the measurement of two calibration standards and a test sample to demonstrate the increased lateral resolution of the instrument.

James W. G. Tyrrell; Claudio Dal Savio; Rolf Krüger-Sehm; Hans-Ulrich Danzebrink

2004-01-01T23:59:59.000Z

195

Rapid Scan AERI Observations: Benefits and Analysis  

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

Rapid Scan AERI Observations: Benefits and Analysis Rapid Scan AERI Observations: Benefits and Analysis W. F. Feltz, D. D. Turner, R. O. Knuteson, and R. G. Dedecker Space Science and Engineering Center Cooperative Institute of Mesoscale Meteorological Studies University of Wisconsin-Madison Madison, Wisconsin D. D. Turner Pacific Northwest National Laboratory Richland, Washington Introduction The U.S. Department of Energy's (DOE's) Atmospheric Radiation Measurement (ARM) Program has funded the development of the atmospheric emitted radiance interferometer (AERI). This has led to a hardened, autonomous system that measures downwelling infrared (IR) radiance at high-spectral resolution. Seven AERI systems have been deployed around the world as part of the ARM Program. The initial goal of these instruments was to characterize the clear-sky IR emission from the atmosphere,

196

Optical memory  

DOE Patents [OSTI]

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.

Mao, Samuel S; Zhang, Yanfeng

2013-07-02T23:59:59.000Z

197

Circular zig-zag scan video format  

DOE Patents [OSTI]

A circular, ziz-zag scan for use with vidicon tubes. A sine wave is generated, rectified and its fourth root extracted. The fourth root, and its inverse, are used to generate horizontal ramp and sync signals. The fourth root is also used to generate a vertical sync signal, and the vertical sync signal, along with the horizontal sync signal, are used to generate the vertical ramp signal. Cathode blanking and preamplifier clamp signals are also obtained from the vertical sync signal.

Peterson, C. Glen (Los Alamos, NM); Simmons, Charles M. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

198

Nanometer-precision electron-beam lithography with applications in integrated optics  

E-Print Network [OSTI]

Scanning electron-beam lithography (SEBL) provides sub-10-nm resolution and arbitrary-pattern generation; however, SEBL's pattern-placement accuracy remains inadequate for future integrated-circuits and integrated-optical ...

Hastings, Jeffrey Todd, 1975-

2003-01-01T23:59:59.000Z

199

Hadamard multimode optical imaging transceiver  

DOE Patents [OSTI]

Disclosed is a method and system for simultaneously acquiring and producing results for multiple image modes using a common sensor without optical filtering, scanning, or other moving parts. The system and method utilize the Walsh-Hadamard correlation detection process (e.g., functions/matrix) to provide an all-binary structure that permits seamless bridging between analog and digital domains. An embodiment may capture an incoming optical signal at an optical aperture, convert the optical signal to an electrical signal, pass the electrical signal through a Low-Noise Amplifier (LNA) to create an LNA signal, pass the LNA signal through one or more correlators where each correlator has a corresponding Walsh-Hadamard (WH) binary basis function, calculate a correlation output coefficient for each correlator as a function of the corresponding WH binary basis function in accordance with Walsh-Hadamard mathematical principles, digitize each of the correlation output coefficient by passing each correlation output coefficient through an Analog-to-Digital Converter (ADC), and performing image mode processing on the digitized correlation output coefficients as desired to produce one or more image modes. Some, but not all, potential image modes include: multi-channel access, temporal, range, three-dimensional, and synthetic aperture.

Cooke, Bradly J; Guenther, David C; Tiee, Joe J; Kellum, Mervyn J; Olivas, Nicholas L; Weisse-Bernstein, Nina R; Judd, Stephen L; Braun, Thomas R

2012-10-30T23:59:59.000Z

200

Extraordinary optical transmission through patterned subwavelength apertures.  

SciTech Connect (OSTI)

Light propagating through a subwavelength aperture can be dramatically increased by etching a grating in the metal around the hole. Moreover, light that would typically broadly diverge when passing through an unpatterned subwavelength hole can be directed into a narrow beam by utilizing a specific pattern around the aperture. While the increased transmission and narrowed angular emission appear to defy far-field diffraction theory, they are consistent with a fortuitous plasmon/photon coupling. In addition, the coupling between photons and surface plasmons affects the emissivity of a surface comprised of such structures. These properties are useful across several strategic areas of interest to Sandia. A controllable emission spectrum could benefit satellite and military application areas. Photolithography and near-field microscopy are natural applications for a system that controls light beyond the diffraction limit in a manner that is easily parallelizable. Over the one year of this LDRD, we have built or modified the numerical tools necessary to model such structures. These numerical codes and the knowledge base for using them appropriately will be available in the future for modeling work on surface plasmons or other optical modeling at Sandia. Using these tools, we have designed and optimized structures for various transmission or emission properties. We demonstrate the ability to design a metallic skin with an emissivity peak at a pre-determined wavelength in the spectrum. We optimize structures for maximum light transmission and show transmitted beams that beat the far-field diffraction limit.

Kemme, Shanalyn A.; El-Kady, Ihab Fathy; Hadley, G. Ronald; Peters, David William; Lanes, Chris E.

2004-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Circular zig-zag scan video format  

DOE Patents [OSTI]

A circular, ziz-zag scan for use with vidicon tubes is disclosed. A sine wave is generated, rectified and its fourth root extracted. The fourth root, and its inverse, are used to generate horizontal ramp and sync signals. The fourth root is also used to generate a vertical sync signal, and the vertical sync signal, along with the horizontal sync signal, are used to generate the vertical ramp signal. Cathode blanking and preamplifier clamp signals are also obtained from the vertical sync signal. 10 figs.

Peterson, C.G.; Simmons, C.M.

1992-06-09T23:59:59.000Z

202

Atomic Force and Scanning Electron Microscopy of Atmospheric Particles  

E-Print Network [OSTI]

conducted so as to characterize atmospheric aerosols from anthropogenic (pollution) and natural (sea saltAtomic Force and Scanning Electron Microscopy of Atmospheric Particles ZAHAVA BARKAY,1 * AMIT 69978, Israel KEY WORDS atmospheric aerosols; atomic force microscopy; scanning electron microscopy

Shapira, Yoram

203

Optics and Diagnostics  

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

2 14 | Next | Last Back to Index Optics Line up of optics after cleaning. Photo Number: 2013-048779...

204

Experimental stress–strain analysis of tapered silica optical fibers with nanofiber waist  

SciTech Connect (OSTI)

We experimentally determine tensile force–elongation diagrams of tapered optical fibers with a nanofiber waist. The tapered optical fibers are produced from standard silica optical fibers using a heat and pull process. Both, the force–elongation data and scanning electron microscope images of the rupture points indicate a brittle material. Despite the small waist radii of only a few hundred nanometers, our experimental data can be fully explained by a nonlinear stress–strain model that relies on material properties of macroscopic silica optical fibers. This is an important asset when it comes to designing miniaturized optical elements as one can rely on the well-founded material characteristics of standard optical fibers. Based on this understanding, we demonstrate a simple and non-destructive technique that allows us to determine the waist radius of the tapered optical fiber. We find excellent agreement with independent scanning electron microscope measurements of the waist radius.

Holleis, S.; Hoinkes, T.; Wuttke, C.; Schneeweiss, P.; Rauschenbeutel, A. [Vienna Center for Quantum Science and Technology, TU Wien—Atominstitut, Stadionallee 2, 1020 Vienna (Austria)

2014-04-21T23:59:59.000Z

205

A System Level Boundary Scan Controller Board for VME Applications  

Science Journals Connector (OSTI)

In this article an application of boundary scan test at system level is analyzed. The objective is met through the description of the design and implementation options of a VME boundary scan controller board prototype and the corresponding software. ... Keywords: ATPG, IEEE 1149.1 boundary scan test, board level test and system level test

Nuno Cardoso; Carlos Beltrán Almeida; José Carlos Da Silva

2001-06-01T23:59:59.000Z

206

Parallel optical sampler  

SciTech Connect (OSTI)

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.

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

2014-05-20T23:59:59.000Z

207

Scanning ARM Cloud Radars Part I: Operational Sampling Strategies  

SciTech Connect (OSTI)

Probing clouds in three-dimensions has never been done with scanning millimeter-wavelength (cloud) radars in a continuous operating environment. The acquisition of scanning cloud radars by the Atmospheric Radiation Measurement (ARM) program and research institutions around the world generate the need for developing operational scan strategies for cloud radars. Here, the first generation of sampling strategies for the Scanning ARM Cloud Radars (SACRs) is discussed. These scan strategies are designed to address the scientific objectives of the ARM program, however, they introduce an initial framework for operational scanning cloud radars. While the weather community uses scan strategies that are based on a sequence of scans at constant elevations, the SACRs scan strategies are based on a sequence of scans at constant azimuth. This is attributed to the cloud properties that are vastly different for rain and snow shafts that are the primary target of precipitation radars. A “cloud surveillance” scan strategy is introduced (HS-RHI) based on a sequence of horizon-to-horizon Range Height Indicator (RHI) scans that sample the hemispherical sky (HS). The HS-RHI scan strategy is repeated every 30 min to provide a static view of the cloud conditions around the SACR location. Between HS-RHI scan strategies other scan strategies are introduced depending on the cloud conditions. The SACRs are pointing vertically in the case of measurable precipitation at the ground. The radar reflectivities are corrected for water vapor attenuation and non-meteorological detection are removed. A hydrometeor detection mask is introduced based on the difference of cloud and noise statistics is discussed.

Kollias, Pavlos; Bharadwaj, Nitin; Widener, Kevin B.; Jo, Ieng; Johnson, Karen

2014-03-01T23:59:59.000Z

208

Optical Packet Switching -1 Optical Networks  

E-Print Network [OSTI]

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

Mellia, Marco

209

Gordon Research Conferences  

Science Journals Connector (OSTI)

...properties and applications ofx-ray absorp-tion...Mechanisms of thin-film growth (Pauline...reactor models in CVD"; Eugene Irene...from liquids and thin-film surfaces...Near-field scanning optical microscopy...Low-temperature thin-film oxi-dation...John-son, "Optical spectroscopy...

ALEXANDER M. CRUICKSHANK

1986-03-07T23:59:59.000Z

210

Optics and Optical Engineering Program Assessment Plan Program Learning Objectives  

E-Print Network [OSTI]

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

Cantlon, Jessica F.

211

Copy of Bound Original For Scanning  

Office of Legacy Management (LM)

Copy of Bound Original Copy of Bound Original For Scanning Document # 1\1\ i g -b DOE/El/-0005/6 Formerly Utilized IVIEWAEC Site! Remedial Action Progrhn, F@diilogical Survey of the Seaway Industrial Par Tonawanda, New Yor May 197 Final Repel Prepared f U.S. Department of Enerc Assistant Secretary for Environme Division of Environmental Control Technolo Washington, D.C. 205, uric Contract No. W-7405-ENG- - - - Available from: ' : -. National Technical Information Service (NTIS) U.S. Department of Comnerce 5285 Port Royal Road Springfield, Virginia 22161 price: Printed Copy: $ 5.25 Microffche: $ 3.00 PREFACE This series of reports results from a program initiated in 1974 by the Atomic Energy Commission (AEC) for determination of the condition of sites formerly utilized by the Manhattan Engineering District &ED)

212

Damage potential characteristics of near-field earthquake motions  

SciTech Connect (OSTI)

In recent major earthquakes; i.e., 1994 Northridge earthquake in the US and 1995 Great Kansai earthquake in Japan, several close-distance strong ground motions have been obtained, which may be of significant interest to earthquake/structural engineers. The damage potential of those recently obtained ground motions is examined based on the nonlinear response analyses of various SDOF systems. For comparison purposes, the El Centro records from the 1940 Imperial Valley earthquake, as well as a set of artificial motions consistent with the R.G. 1.60 spectrum were also used. The engineering insights regarding the seismic design of structures are discussed based on a series of parametric studies.

Park, Y. [Brookhaven National Lab., Upton, NY (United States); Chokshi, N. [Nuclear Regulatory Commission, Washington, DC (United States)

1997-04-01T23:59:59.000Z

213

Heat Transfer between Two Nanoparticles Through Near Field Interaction  

Science Journals Connector (OSTI)

We introduce a thermal conductance by using the fluctuation-dissipation theorem to analyze the heat transfer between two nanoparticles separated by a submicron distance. Using either a molecular dynamics technique or a model based on the Coulomb interaction between fluctuating dipoles, we derive the thermal conductance. Both models agree for distances larger than a few diameters. For separation distances smaller than the particle diameter, we find a transition regime characterized by a thermal conductance larger than the contact conductance.

Gilberto Domingues; Sebastian Volz; Karl Joulain; Jean-Jacques Greffet

2005-03-02T23:59:59.000Z

214

NEAR-FIELD IMAGING OF INFINITE ROUGH SURFACES 1 ...  

E-Print Network [OSTI]

analytic solution for the direct scattering problem is derived from the method of ... mine the scattered field from the incident field and the differential equation governing the wave .... is the unit outward normal vector on S, given explicitly as ...... the periodicity of the solutions, we modified a simple mesh generator in MATLAB by.

2013-09-03T23:59:59.000Z

215

Near-field microscopy: throwing light on the nanoworld  

Science Journals Connector (OSTI)

...instrumentation methods Nanotechnology instrumentation methods...tial for drug discovery, medicine and nanotechnology, while the development...in the life sciences and nanotechnology, and I believe we are now...

2003-01-01T23:59:59.000Z

216

INVERSE MEDIUM SCATTERING PROBLEMS IN NEAR-FIELD ...  

E-Print Network [OSTI]

measured in the far-field zone as a function of the probe position. In TIRM, the sample is ... to be considered, thus defining an interface between two half-spaces

2007-05-08T23:59:59.000Z

217

Near-Field Imaging of Interior Cavities 1 Introduction  

E-Print Network [OSTI]

[14] NIST Digital Library of Mathematical Functions. http://dlmf.nist.gov/, Release ... [26] F. Zeng, F. Cakoni and J. Sun, An inverse electromagnetic scattering ...

2014-07-04T23:59:59.000Z

218

Optical microphone  

DOE Patents [OSTI]

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.

Veligdan, James T. (Manorville, NY)

2000-01-11T23:59:59.000Z

219

V-119: IBM Security AppScan Enterprise Multiple Vulnerabilities |  

Broader source: Energy.gov (indexed) [DOE]

9: IBM Security AppScan Enterprise Multiple Vulnerabilities 9: IBM Security AppScan Enterprise Multiple Vulnerabilities V-119: IBM Security AppScan Enterprise Multiple Vulnerabilities March 26, 2013 - 12:56am Addthis PROBLEM: IBM Security AppScan Enterprise Multiple Vulnerabilities PLATFORM: IBM Rational AppScan 5.x IBM Rational AppScan 8.x ABSTRACT: IBM has acknowledged multiple vulnerabilities REFERENCE LINKS: IBM Reference #:1626264 Secunia Advisory SA52764 CVE-2008-4033 CVE-2012-4431 CVE-2012-5081 CVE-2013-0473 CVE-2013-0474 CVE-2013-0510 CVE-2013-0511 CVE-2013-0512 CVE-2013-0513 CVE-2013-0532 IMPACT ASSESSMENT: Medium DISCUSSION: 1) The application allows users to perform certain actions via HTTP requests without performing proper validity checks to verify the requests. This can be exploited to e.g. cause a DoS when a logged-in user visits a

220

Optical data latch  

DOE Patents [OSTI]

An optical data latch is formed on a substrate from a pair of optical logic gates in a cross-coupled arrangement in which optical waveguides are used to couple an output of each gate to an photodetector input of the other gate. This provides an optical bi-stability which can be used to store a bit of optical information in the latch. Each optical logic gate, which can be an optical NOT gate (i.e. an optical inverter) or an optical NOR gate, includes a waveguide photodetector electrically connected in series with a waveguide electroabsorption modulator. The optical data latch can be formed on a III-V compound semiconductor substrate (e.g. an InP or GaAs substrate) from III-V compound semiconductor layers. A number of optical data latches can be cascaded to form a clocked optical data shift register.

Vawter, G. Allen (Corrales, NM)

2010-08-31T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Positron Emission Tomography (PET) and Positron Scanning  

Office of Scientific and Technical Information (OSTI)

DOE R&D Accomplishments DOE R&D Accomplishments Search All Database Web Pages for Go The Basics Home About What's New FAQ Contact Us Laureates Nobel Laureates Fermi Laureates Nobel Physicists Nobel Chemists Medicine Nobels Explore Insights SC Stories Snapshots R&D Nuggets Database Search Browse Reports Database Help Finding Aids Site Map A - Z Index Menu Synopsis Blog Archive QR Code RSS Archive Tag Cloud Videos Widget XML Bookmark and Share Positron Emission Tomography (PET) and Positron Scanning Resources with Additional Information Positron Emission Tomography (PET) Scanner Courtesy Lawrence Berkeley National Laboratory 'Positron Emission Tomography ... [is a medical imaging technique that] can track chemical reactions in living tissues and merges chemistry with biological imaging. Its strength has been in studies of the brain where there has been significant progress in investigations of drug addiction, aging, mental illness, and neurogenic disorders. Positron Emission Tomography (PET) had its genesis in hot-atom chemical research supported by the Chemical Sciences Division of the Office of Basic Energy Sciences. Through this research it was learned, over many years, how to prepare short-lived positron emitters such as 18F whose half-life is 110 minutes. In 1975, the molecule [18F]fluorodeoxyglucose was successfully synthesized at Brookhaven National Laboratory (BNL) and set the stage for Positron Emission Tomography of the human brain.'

222

Lansce Wire Scanning Diagnostics Device Mechanical Design  

SciTech Connect (OSTI)

The Accelerator Operations & Technology Division at Los Alamos National Laboratory operates a linear particle accelerator which utilizes 110 wire scanning diagnostics devices to gain position and intensity information of the proton beam. In the upcoming LANSCE improvements, 51 of these wire scanners are to be replaced with a new design, up-to-date technology and off-the-shelf components. This document outlines the requirements for the mechanical design of the LANSCE wire scanner and presents the recently developed linac wire scanner prototype. Additionally, this document presents the design modifications that have been implemented into the fabrication and assembly of this first linac wire scanner prototype. Also, this document will present the design for the second, third, and fourth wire scanner prototypes being developed. Prototypes 2 and 3 belong to a different section of the particle accelerator and therefore have slightly different design specifications. Prototype 4 is a modification of a previously used wire scanner in our facility. Lastly, the paper concludes with a plan for future work on the wire scanner development.

Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Batygin, Yuri K. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Maestas, Alfred J. [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Raybun, Joseph L. [Los Alamos National Laboratory; Sattler, F. D. [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

223

Chaotic oscillation and random-number generation based on nanoscale optical-energy transfer  

E-Print Network [OSTI]

By using nanoscale energy-transfer dynamics and density matrix formalism, we demonstrate theoretically and numerically that chaotic oscillation and random-number generation occur in a nanoscale system. The physical system consists of a pair of quantum dots (QDs), with one QD smaller than the other, between which energy transfers via optical near-field interactions. When the system is pumped by continuous-wave radiation and incorporates a timing delay between two energy transfers within the system, it emits optical pulses. We refer to such QD pairs as nano-optical pulsers (NOPs). Irradiating an NOP with external periodic optical pulses causes the oscillating frequency of the NOP to synchronize with the external stimulus. We find that chaotic oscillation occurs in the NOP population when they are connected by an external time delay. Moreover, by evaluating the time-domain signals by statistical-test suites, we confirm that the signals are sufficiently random to qualify the system as a random-number generator (RNG). This study reveals that even relatively simple nanodevices that interact locally with each other through optical energy transfer at scales far below the wavelength of irradiating light can exhibit complex oscillatory dynamics. These findings are significant for applications such as ultrasmall RNGs.

Makoto Naruse; Song-Ju Kim; Masashi Aono; Hirokazu Hori; Motoichi Ohtsu

2014-12-19T23:59:59.000Z

224

A 3D scanning system for biomedical purposes  

Science Journals Connector (OSTI)

The use of three-dimensional (3D) scanning systems for acquiring the external shape features of biological objects has recently been gaining popularity in the biomedical field. A simple, low cost, 3D scanning system is presented, which employs ... Keywords: 3D geometric modelling, 3D scanning, EFDs, biological objects, biomedical scanners, camera calibration, data acquisition, direct linear transformation, elliptical Fourier descriptors, laser light-sectioning, medical imaging, shape features

B. D. Bradley; A. D. C. Chan; M. J. D. Hayes

2009-06-01T23:59:59.000Z

225

Optics and Diagnostics  

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

1 14 | Next | Last Back to Index Optics Optics processing of Target Wedged Focus Lens into cleaningcoating frame. Photo Number: 2013-048765...

226

Optics and Diagnostics  

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

3 14 | Next | Last Back to Index Optics Alignment Conducting an optics alignment after replacement of a Pockels Cell in the clean room. Photo Number: 2013-050691...

227

Optics and Diagnostics  

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

9 14 | Next | Last Back to Index Optics Processing Optics for the National Ignition Facility must be manufactured to exacting standards. To ensure quality, precise measurements...

228

Optical NAND gate  

SciTech Connect (OSTI)

An optical NAND gate is formed from two pair of optical waveguide devices on a substrate, with each pair of the optical waveguide devices consisting of an electroabsorption modulator and a photodetector. One pair of the optical waveguide devices is electrically connected in parallel to operate as an optical AND gate; and the other pair of the optical waveguide devices is connected in series to operate as an optical NOT gate (i.e. an optical inverter). The optical NAND gate utilizes two digital optical inputs and a continuous light input to provide a NAND function output. The optical NAND 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.

Skogen, Erik J. (Albuquerque, NM); Raring, James (Goleta, CA); Tauke-Pedretti, Anna (Albuquerque, NM)

2011-08-09T23:59:59.000Z

229

Transparent Metal Films for Detection of Single-Molecule Optical Absorption by Scanning Tunneling Microscopy  

Science Journals Connector (OSTI)

To ensure better contact between the sample holder and the thin films, thick silver contacts are deposited at the sample edge using colloidal silver paint (Ted Pella Inc.). ... Berciaud, S.; Cognet, L.; Poulin, P.; Weisman, R. B.; Lounis, B.Absorption Spectroscopy of Individual Single-Walled Carbon Nanotubes Nano Lett. ...

Lea Nienhaus; Gregory E. Scott; Richard T. Haasch; Sarah Wieghold; Joseph W. Lyding; Martin Gruebele

2014-05-22T23:59:59.000Z

230

ProxiScan?: A Novel Camera for Imaging Prostate Cancer  

ScienceCinema (OSTI)

ProxiScan is a compact gamma camera suited for high-resolution imaging of prostate cancer. Developed by Brookhaven National Laboratory and Hybridyne Imaging Technologies, Inc., ProxiScan won a 2009 R&D 100 Award, sponsored by R&D Magazine to recognize t

Ralph James

2010-01-08T23:59:59.000Z

231

Fast 3D Scanning for Biometric Identification and Verification  

E-Print Network [OSTI]

Fast 3D Scanning for Biometric Identification and Verification June 2011 Authors Anselmo., & Chen, A. (2011). Fast 3D Scanning for Biometric Identification and Verification. (Prepared by RTI..................................................10 Summary and Findings for Integration of Imperceptible Structured Lighting and SIS's 3D Snapshot

McShea, Daniel W.

232

Reducing Photobleaching in STED Microscopy with Higher Scanning Speed  

E-Print Network [OSTI]

Photobleaching is a major limitation of super-resolution STED microscopy. We show that the photobleaching rate in STED microscopy is slowed down by scanning with a higher linear speed, enabled by the large field of view in our custom-built resonant-scanning STED microscope. The effect of scanning speed on photobleaching is more remarkable at higher levels of depletion laser irradiance. With a depletion irradiance of 0.4 GW/cm$^2$ (time average), we were able to slow down the photobleaching of the Atto 647N dye by 80% with 8-fold faster scanning. Photobleaching is primarily caused by the depletion light acting upon the excited fluorophores. Experimental data qualitatively agree with a theoretical model. Our results encourage further increasing linear scanning speed for photobleaching reduction in STED microscopy.

Wu, Yong

2014-01-01T23:59:59.000Z

233

Fiber optic connector  

DOE Patents [OSTI]

A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled.

Rajic, Slobodan (Knoxville, TN); Muhs, Jeffrey D. (Lenior City, TN)

1996-01-01T23:59:59.000Z

234

Optical NOR gate  

DOE Patents [OSTI]

An optical NOR gate is formed from two pair of optical waveguide devices on a substrate, with each pair of the optical waveguide devices consisting of an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical NOR gate utilizes two digital optical inputs and a continuous light input to provide a NOR function digital optical output. The optical NOR 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.

Skogen, Erik J. (Albuquerque, NM); Tauke-Pedretti, Anna (Albuquerque, NM)

2011-09-06T23:59:59.000Z

235

Parameter Scan of an Effective Group Difference Pseudopotential Using Grid Computing 1 Parameter Scan of an Effective Group Difference  

E-Print Network [OSTI]

Parameter Scan of an Effective Group Difference Pseudopotential Using Grid Computing 1 Parameter Scan of an Effective Group Difference Pseudopotential Using Grid Computing Wibke SUDHOLT and Kim K of the actual biology/biochemistry. The ability to invoke modern grid technologies offers the ability to create

Abramson, David

236

The features of a quantum description of radiation in an optically dense medium  

E-Print Network [OSTI]

This paper is devoted to the theory of quantum electromagnetic field in an optically dense medium. Self-consistent equations describing interaction between a quantum field and a quantum dielectric medium are obtained from the first principles, i.e., outside a phenomenological description. Using these equations, we found a transformation (of the Bogoliubov transformation type) that converts the operators of the "vacuum" field into operators of collective perturbations of the field and an ensemble of atoms, that is, photons in the medium. Transformation parameter is the refractive index of the wave mode considered. It is shown that besides the energy of the collective electromagnetic field, the energy of photons in the medium includes the energy of the internal degrees of freedom of the substance and the energy of near-field dipole interaction between atoms in the polarized medium. The concept of negative energy photons is introduced on the basis of self-consistent equations.

Tokman, M D; Vdovin, V V

2015-01-01T23:59:59.000Z

237

Controlling the dynamics of quantum mechanical systems sustaining dipole-forbidden transitions via optical nanoantennas  

Science Journals Connector (OSTI)

We suggest to excite dipole-forbidden transitions in quantum mechanical systems by using appropriately designed optical nanoantennas. The antennas are tailored such that their near field contains sufficiently strong contributions of higher-order multipole moments. The strengths of these moments exceed their free-space analogs by several orders of magnitude. The impact of such excitation enhancement is exemplarily investigated by studying the dynamics of a three-level system. It decays upon excitation by an electric quadrupole transition via two electric dipole transitions. Since one dipole transition is assumed to be radiative, the enhancement of this emission serves as a figure of merit. Such self-consistent treatment of excitation, emission, and internal dynamics as developed in this contribution is the key to predict any observable quantity. The suggested scheme may represent a blueprint for future experiments and will find many obvious spectroscopic and sensing applications.

Robert Filter; Stefan Mühlig; Toni Eichelkraut; Carsten Rockstuhl; Falk Lederer

2012-07-05T23:59:59.000Z

238

Induction of DNA Damage by Low Dose PET scans  

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

Induction of DNA Damage by Low Dose PET scans Induction of DNA Damage by Low Dose PET scans Douglas Boreham McMaster University Abstract This research is focused on assessing the radiation risk associated with positron emission tomography (PET) scans. It has been suggested that low dose medical imaging, such as PET scans, carry an added biological risk because they expose the patient to ionizing radiation. PET scanning is an increasingly used nuclear medicine procedure that requires the administration of isotope 18F-fluorodeoxyglucose (18F-FDG, E=250 keV β and 511 keV γ) and results in an effective dose to the patient ranging from 7-22 mSv. The radiation induced DNA damage associated with a PET scan was studied in 7-9 week old female wild type Trp53 +/+ mice. Mice were given a PET scan with 18F-FDG and the biological response was assessed in bone marrow using

239

Latching micro optical switch  

DOE Patents [OSTI]

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.

Garcia, Ernest J; Polosky, Marc A

2013-05-21T23:59:59.000Z

240

Scanning probe microscopy with inherent disturbance suppression using micromechanical systems  

E-Print Network [OSTI]

All scanning probe microscopes (SPMs) are affected by disturbances, or mechanical noise, in their environments which can limit their imaging resolution. This thesis introduces a general approach for suppressing out-of-plane ...

Sparks, Andrew William, 1977-

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Sub-Kelvin scanning tunneling microscopy on magnetic molecules.  

E-Print Network [OSTI]

??Magnetic molecules have attracted lots interest. In this work, an ultra-stable and low noise scanning tunneling microscopy operating at 400 mK using He-3 (930 mK… (more)

Zhang, Lei

2012-01-01T23:59:59.000Z

242

Information efficiency of line-scan imaging mechanisms  

Science Journals Connector (OSTI)

Information theory is used to formulate a single figure of merit for assessing the performance of line-scan imaging systems as a function of their spatial response (PSF or MTF),...

Huck, F O; Halyo, N; Park, S K

1981-01-01T23:59:59.000Z

243

Iran Thomas Auditorium, 8600 Transport Measurements by Scanning...  

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

8600 Transport Measurements by Scanning Probe Microscopy: Possibilities for Graphene Randall M. Feenstra Department of Physics Carnegie Mellon University CNMS D D I I S S C C O O...

244

Dynamic study of tunable stiffness scanning microscope probe  

E-Print Network [OSTI]

This study examines the dynamic characteristics of the in-plane tunable stiffness scanning microscope probe for an atomic force microscope (AFM). The analysis was carried out using finite element analysis (FEA) methods for ...

Vega González, Myraida Angélica

2005-01-01T23:59:59.000Z

245

System Provides Clear Brain Scans of Awake, Unrestrained Mice...  

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

System Provides Clear Brain Scans of Awake, Unrestrained Mice dynamic imaging of mice Three markers attached to the head of a mouse enable the AwakeSPECT system to obtain detailed,...

246

Achieving sub-10-nm resolution using scanning electron beam lithography  

E-Print Network [OSTI]

Achieving the highest possible resolution using scanning-electron-beam lithography (SEBL) has become an increasingly urgent problem in recent years, as advances in various nanotechnology applications have driven demand for ...

Cord, Bryan M. (Bryan Michael), 1980-

2009-01-01T23:59:59.000Z

247

Multi-atlas segmentation in head and neck CT scans  

E-Print Network [OSTI]

We investigate automating the task of segmenting structures in head and neck CT scans, to minimize time spent on manual contouring of structures of interest. We focus on the brainstem and left and right parotids. To generate ...

Arbisser, Amelia M

2012-01-01T23:59:59.000Z

248

Observing Warm Clouds in 3D Using ARM Scanning Cloud  

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

Observing Warm Clouds in 3D Using ARM Scanning Cloud Radars and a Novel Ensemble Method For original submission and image(s), see ARM Research Highlights http:www.arm.gov...

249

Construction of an ultra-low temperature scanning tunneling microscope  

Science Journals Connector (OSTI)

We describe designs and specifications of an ultra-low temperature scanning tunneling microscope developed at ... works over a wide temperature range between 90 mK and 300 K with atomic resolution as...

Hiroshi Fukuyama; Hiroki Tan; Tetsuya Handa…

1996-01-01T23:59:59.000Z

250

First Observations of Tracking Clouds Using Scanning ARM Cloud Radars  

Science Journals Connector (OSTI)

Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large-drop formation (weather radar “first echo”). These measurements also complement cloud and precipitation tracking using ...

Paloma Borque; Pavlos Kollias; Scott Giangrande

2014-12-01T23:59:59.000Z

251

Detection of bone disease in dogs by radioisotope scanning  

E-Print Network [OSTI]

, delayed union, and nonunion), osteomyelitis, degenerative arthritis, surgical osteotomy, i'ibrous dysplasia, osteochondromatosie, and growing epiphyses. Radioisotopic scanning has been reported 12 for studying the metabolism of Fluorine-18 in dogs 9..., ( 1962): 95-104. 2. Bauer, G. C. H. , and Smith, E. M. r Sr 85 Sointimetry in Osteoarthritis of the Knee. J . Nucl. Med. , 10, (Mar. , 1969): 109-116. Blau, M. , Nagler, W. , and Bender, M. A. : Fluorine ? 18. A New Isotope for Bone Scanning. J. Nucl...

Morris, Earl Louis

2012-06-07T23:59:59.000Z

252

CMOS ROM arrays programmable by laser beam scanning  

E-Print Network [OSTI]

CMOS ROM ARRAYS PROGRAMMABLE BY LASER BEAM SCANNING A Thesis bY JONG JUNE LEE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1984 Major Subject... : Electrical Engineering CMOS ROM ARRAYS PROGRAMMABLE BY LASER BEAM SCANNING A Thesis by JONGJUNE LEE Approved as to style and content by: Noel R. Strader II (Chairman of Committee) Philli E. Allen (Member) Philip S. Noe (Member) Daniel Colunga...

Lee, Jongjune

2012-06-07T23:59:59.000Z

253

Pencil Beam Scanning System Based On A Cyclotron  

SciTech Connect (OSTI)

Sumitomo Heavy Industries, Ltd. (SHI) has developed a new pencil beam scanning system (PBS) for proton therapy in collaboration with National Cancer Center Hospital East (NCCHE). Taking advantage of the continuous beam from the cyclotron P235, the line scanning method is employed in order to realize continuous irradiation with high dose rate. 3D uniform and sphere field was irradiated and compared with the simulation.

Tachikawa, Toshiki; Nonaka, Hideki; Kumata, Yukio [Sumitomo Heavy Industries, Ltd., 5-2 Soubiraki-cho, Niihama, Ehime 792-8588 (Japan); Nishio, Teiji; Ogino, Takashi [National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577 (Japan)

2011-06-01T23:59:59.000Z

254

LINEAR SCANNING METHOD BASED ON THE SAFT COARRAY  

SciTech Connect (OSTI)

This work presents a method to obtain B-scan images based on linear array scanning and 2R-SAFT. Using this technique some advantages are obtained: the ultrasonic system is very simple; it avoids the grating lobes formation, characteristic in conventional SAFT; and subaperture size and focussing lens (to compensate emission-reception) can be adapted dynamically to every image point. The proposed method has been experimentally tested in the inspection of CFRP samples.

Martin, C. J.; Martinez-Graullera, O.; Romero, D.; Ullate, L. G. [Instituto de Automatica Industrial-CSIC, Carretera de Campo Real, km 0.200, La Poveda, Arganda del Rey, Madrid, E-28500 (Spain); Higuti, R. T. [UNESP-Universidade Estadual Paulista, Dep. Electrical Engineering, Av. Brasil, 56, 15385-000, Ilha Solteira, SP (Brazil)

2010-02-22T23:59:59.000Z

255

High bandwidth optical mount  

DOE Patents [OSTI]

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.

Bender, Donald A. (Dublin, CA); Kuklo, Thomas (Oakdale, CA)

1994-01-01T23:59:59.000Z

256

Optics and Diagnostics  

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

test optic after receiving chemical process called AMP2.5, which is under development for increasing the damage threshold of 3 fused silica optics. Photo Number: 2013-05031...

257

NIF Final Optics Assemblies  

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

NIF Final Optics Assemblies The Final Optics Assemblies (FOAs) are the last element of the main laser system and the first of the target area systems. Each FOA contains four...

258

Optic Orientation in Stereo  

Science Journals Connector (OSTI)

The visualization and representation of optic orientation is the nittygritty of practical optical mineralogy. A complete description is concisely made with the use of a stereographic projection. Perspective dr...

Richard E. Stoiber; Stearns A. Morse

1994-01-01T23:59:59.000Z

259

Colored optical glass  

Science Journals Connector (OSTI)

The Lytkarino Optical Glass Factory manufactures various types of colored optical glasses: yellow, orange, and red glasses and glasses that are transparent in the IR region, as well as...

Mogil’naya, L G; Zinov’eva, O B; Firsova, Yu A; Gulyukin, M N

2013-01-01T23:59:59.000Z

260

''Atomic Optics'': Nonimaging Optics on the Nanoscale  

SciTech Connect (OSTI)

This is the final report for a one year close out extension of our basic research program that was established at the University of Chicago more than sixteen years ago to explore and develop the optical sub-discipline that has come to be known as ''nonimaging optics''. This program has been extremely fruitful, having both broadened the range of formalism available for workers in this field and led to the discovery of many new families of optical devices. These devices and techniques have applications wherever the efficient transport and transformation of light distributions are important, in particular in illumination, fiber optics, collection and concentration of sunlight, and the detection of faint light signals in physics and astrophysics. Over the past thirty years, Nonimaging Optics (Welford and Winston, 1989) has brought a fresh approach to the analysis of many problems in classical macro-scale optics. Through the application of phase-space concepts, statistical methods, thermodynamic arguments, etc., many previously established performance limits were able to be broken and many technical surprises with exciting practical applications were discovered. The most recent three-year phase of our long-term continuing program ended in late 2002 and emphasized extending our work in geometrical optics and expanding it to include some interesting questions in physical optics as well as in the new field of statistical optics. This report presents a survey of the basic history and concepts of nonimaging optics and reviews highlights and significant accomplishments over the past fifteen years. This is followed by a more detailed summary of recent research directions and accomplishments during the last three years. This most recent phase was marked by the broadening in scope to include a separate project involving a collaboration with an industrial partner, Science Applications International Corporation (SAIC). This effort was proposed and approved in 1998 and was incorporated into this project (September, 1998) with the required additional funding provided through this already existing grant.

Roland Winston Joseph O'Gallagher

2005-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Optics and Diagnostics  

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

10 14 | Next | Last Back to Index Optics Diffraction Gratings for APPOLON laser. Photo Number: 2011-020040...

262

Optical voltage reference  

DOE Patents [OSTI]

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.

Rankin, R.; Kotter, D.

1994-04-26T23:59:59.000Z

263

Thermodynamics of Optical Tweezers  

Science Journals Connector (OSTI)

We discuss the measurement of the gradient and scattering forces based on a thermodynamic treatment of optical tweezers.

Stilgoe, Alexander B; Nguyen, Lan T P; Nieminen, Timo A; Rubinsztein-Dunlop, Halina

264

Magnetic Force Between Magnetic Nano Probes at Optical Frequency  

E-Print Network [OSTI]

Magnetic force microscopy based on the interaction of static magnetic materials was demonstrated in the past with resolutions in the order of nanometers. Measurement techniques based on forces between electric dipoles oscillating at optical frequencies have been also demonstrated leading to the standard operation of the scanning force microscope (SFM). However the investigations of a SFM based on the magnetic force generated by magnetic dipole moments oscillating at optical frequencies has not been tackled yet. With this goal in mind we establish a theoretical model towards observable magnetic force interaction between two magnetically polarizable nanoparticles at optical frequency and show such a force to be in the order of piconewtons which could be in principle detected by conventional microscopy techniques. Two possible principles for conceiving magnetically polarizable nano probes able to generate strong magnetic dipoles at optical frequency are investigated based on silicon nanoparticles and on clusters...

Guclu, Caner; Capolino, Filippo

2014-01-01T23:59:59.000Z

265

Optical Diagnostics Thomas Tsang  

E-Print Network [OSTI]

Optical Diagnostics Thomas Tsang · tight environment · high radiation area · non-serviceable area · passive components · optics only, no active electronics · transmit image through flexible fiber bundle #12;New imaging fiber bundle Core size: 12 µm, diameter: 1/8" Optical Diagnostics Total fiber counts ~50

McDonald, Kirk

266

REVIEW ARTICLE Optical trapping  

E-Print Network [OSTI]

REVIEW ARTICLE Optical trapping Keir C. Neuman and Steven M. Blocka) Department of Biological ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology--and the measurement of nanometer-level displacements of--optically trapped objects. We review progress

Block, Steven

267

University of Central Florida College of Optics & Photonics Optics  

E-Print Network [OSTI]

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

Van Stryland, Eric

268

Local Optical Spectroscopies for Subnanometer Spatial Resolution Chemical Imaging  

SciTech Connect (OSTI)

The evanescently coupled photon scanning tunneling microscopes (STMs) have special requirements in terms of stability and optical access. We have made substantial improvements to the stability, resolution, and noise floor of our custom-built visible-photon STM, and will translate these advances to our infrared instrument. Double vibration isolation of the STM base with a damping system achieved increased rigidity, giving high tunneling junction stability for long-duration and high-power illumination. Light frequency modulation with an optical chopper and phase-sensitive detection now enhance the signal-to-noise ratio of the tunneling junction during irradiation.

Weiss, Paul

2014-01-20T23:59:59.000Z

269

Near perfect optics  

SciTech Connect (OSTI)

This report discusses a novel fabrication process to produce nearly perfect optics. The process utilizes vacuum deposition techniques to optimally modify polished optical substrate surfaces. The surface figure, i.e. contour of a polished optical element, is improved by differentially filling in the low spots on the surface using flux from a physical vapor deposition source through an appropriate mask. The process is expected to enable the manufacture of diffraction-limited optical systems for the UV, extreme UV, and soft X-ray spectral regions, which would have great impact on photolithography and astronomy. This same technique may also reduce the fabrication cost of visible region optics with aspheric surfaces.

Goeke, R.; Farnsworth, A.V.; Neumann, C.C.; Sweatt, W.C.; Warren, M.E.; Weed, J.W.

1996-06-01T23:59:59.000Z

270

The StarScan plate measuring machine: overview and calibrations  

E-Print Network [OSTI]

The StarScan machine at the U.S. Naval Observatory (USNO) completed measuring photographic astrograph plates to allow determination of proper motions for the USNO CCD Astrograph Catalog (UCAC) program. All applicable 1940 AGK2 plates, about 2200 Hamburg Zone Astrograph plates, 900 Black Birch (USNO Twin Astrograph) plates, and 300 Lick Astrograph plates have been measured. StarScan comprises of a CCD camera, telecentric lens, air-bearing granite table, stepper motor screws, and Heidenhain scales to operate in a step-stare mode. The repeatability of StarScan measures is about 0.2 micrometer. The CCD mapping as well as the global table coordinate system has been calibrated using a special dot calibration plate and the overall accuracy of StarScan x,y data is derived to be 0.5 micrometer. Application to real photographic plate data shows that position information of at least 0.65 micrometer accuracy can be extracted from course grain 103a-type emulsion astrometric plates. Transformations between "direct" and "reverse" measures of fine grain emulsion plate measures are obtained on the 0.3 micrometer level per well exposed stellar image and coordinate, which is at the limit of the StarScan machine.

Norbert Zacharias; Lars Winter; Ellis Holdenried; Jean-Pierre de Cuyper; Ted Rafferty; Gary Wycoff

2008-06-02T23:59:59.000Z

271

Modular Optical PDV System  

SciTech Connect (OSTI)

A modular optical photon Doppler velocimetry (PDV) detector system has been developed by using readily available optical components with a 20-GHz Miteq optical detector into eight channels of single-wide modules integrated into a 3U rack unit (1U = 1.75 inches) with a common power supply. Optical fibers were precisely trimmed, welded, and timed within each unit. This system has been used to collect dynamic velocity data on various physics experiments. An optical power meter displays the laser input power to the module and optical power at the detector. An adjustable micro-electromechanical system (MEMS) optical attenuator is used to adjust the amount of unshifted light entering the detector. Front panel LEDs show the presence of power to the module. A fully loaded chassis with eight channels consumes 45 watts of power. Each chassis requires 1U spacing above and below for heat management. Modules can be easily replaced.

Araceli Rutkowski, David Esquibel

2008-12-11T23:59:59.000Z

272

Fiber optic vibration sensor  

DOE Patents [OSTI]

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.

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

1995-01-01T23:59:59.000Z

273

Fiber optic vibration sensor  

DOE Patents [OSTI]

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.

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

1995-01-10T23:59:59.000Z

274

E-Print Network 3.0 - analyzer vertically scanning Sample Search...  

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

University, New York, NY 10027 Effects of Scanning Schemes on Laser Tube Bending Four laser... scanning schemes for tube bending, including point-source circumferential ......

275

E-Print Network 3.0 - analytical scanning electron Sample Search...  

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

Electron Microscope Philips CM20 Analytical Scanning... during formation of the carbide particles. 12;Philips CM20 Analytical Scanning Transmission Electron... at SCSAM ...

276

Scanning Transmission Electron Microscopy Investigations of Complex Oxides  

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

Scanning Transmission Electron Microscopy Investigations of Complex Oxides Scanning Transmission Electron Microscopy Investigations of Complex Oxides Monday, May 23, 2011 - 3:30pm SSRL Conference room 137-322 Professor Tom Vogt, NanoCenter & Department of Chemistry, University of South Carolina High-Angle-Annular-Dark-Field/Scanning Transmission Electron Microscopy (HAADF/STEM) is a technique uniquely suited for detailed studies of the structure and composition of complex oxides. The HAADF detector collects electrons which have interact inelastically with the potentials of the atoms in the specimen and therefore resembles the better known Z2 (Z is atomic number) Rutherford scattering. One class of important catalysts consists of bronzes based on pentagonal {Mo6O21} building units; these include Mo5O14 and Mo17O47. In the last 20 years, new materials doped with

277

Composition analysis by scanning femtosecond laser ultraprobing (CASFLU).  

DOE Patents [OSTI]

The composition analysis by scanning femtosecond ultraprobing (CASFLU) technology scans a focused train of extremely short-duration, very intense laser pulses across a sample. The partially-ionized plasma ablated by each pulse is spectrometrically analyzed in real time, determining the ablated material's composition. The steering of the scanned beam thus is computer directed to either continue ablative material-removal at the same site or to successively remove nearby material for the same type of composition analysis. This invention has utility in high-speed chemical-elemental, molecular-fragment and isotopic analyses of the microstructure composition of complex objects, e.g., the oxygen isotopic compositions of large populations of single osteons in bone.

Ishikawa, Muriel Y. (Livermore, CA); Wood, Lowell L. (Simi Valley, CA); Campbell, E. Michael (Danveille, CA); Stuart, Brent C. (Livermore, CA); Perry, Michael D. (Livermore, CA)

2002-01-01T23:59:59.000Z

278

The scanning Compton polarimeter for the SLD experiment  

SciTech Connect (OSTI)

For the 1994/95 run of the SLD experiment at SLAC, a Compton polarimeter measured the luminosity-weighted electron beam polarization to be (77.2 {+-} 0.5)%. This excellent accuracy is achieved by measuring the rate asymmetry of Compton-scattered electrons near the kinematic endpoint. The polarimeter takes data continuously while the electron and positron beams are in collision and achieves a statistical precision of better than 1% in a three minute run. To calibrate the polarimeter and demonstrate its accuracy, many scans are frequently done. These include scans of the laser polarization, the detector position with respect to the kinematic edge, and the laser power.

Woods, M.; SLD Collaboration

1996-10-01T23:59:59.000Z

279

Transpiration purged optical probe  

DOE Patents [OSTI]

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.

2004-01-06T23:59:59.000Z

280

Quantum optical waveform conversion  

E-Print Network [OSTI]

Currently proposed architectures for long-distance quantum communication rely on networks of quantum processors connected by optical communications channels [1,2]. The key resource for such networks is the entanglement of matter-based quantum systems with quantum optical fields for information transmission. The optical interaction bandwidth of these material systems is a tiny fraction of that available for optical communication, and the temporal shape of the quantum optical output pulse is often poorly suited for long-distance transmission. Here we demonstrate that nonlinear mixing of a quantum light pulse with a spectrally tailored classical field can compress the quantum pulse by more than a factor of 100 and flexibly reshape its temporal waveform, while preserving all quantum properties, including entanglement. Waveform conversion can be used with heralded arrays of quantum light emitters to enable quantum communication at the full data rate of optical telecommunications.

D Kielpinski; JF Corney; HM Wiseman

2010-10-11T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Optical atomic magnetometer  

DOE Patents [OSTI]

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.

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

2013-11-19T23:59:59.000Z

282

International Scan on Pedestrian and Bicyclist Safety and Mobility  

E-Print Network [OSTI]

­ Differences in culture and behavior, but these can adapt over time ­ Typical safety evaluations mayInternational Scan on Pedestrian and Bicyclist Safety and Mobility: May 2009 Sponsored by Federal Pedestrian and Bicyclist Safety and Mobility ­ Policy ­ Engineering ­ Education ­ Enforcement · Safe Routes

Bertini, Robert L.

283

Characterization of adsorbates by2 transient measurements in Scanning3  

E-Print Network [OSTI]

1 1 Characterization of adsorbates by2 transient measurements in Scanning3 Electrochemical electrochemical microscopy in2 transient mode allows the investigation of adsorbate intermediates at a polarized3 measurement of the electrochemical6 impedance allowed the complex differential capacitance for each adsorbed

Boyer, Edmond

284

Scanning tunneling spectroscopy of suspended single-wall carbon nanotubes  

E-Print Network [OSTI]

Scanning tunneling spectroscopy of suspended single-wall carbon nanotubes B. J. LeRoy,a) S. G-wall carbon nanotubes that are freely suspended over a trench. The nanotubes were grown by chemical vapor on the freestanding portions of the nanotubes. Spatially resolved spectroscopy on the suspended portion of both

Dekker, Cees

285

Surround structured lighting: 3-D scanning with orthographic illumination  

Science Journals Connector (OSTI)

This paper presents a new system for rapidly acquiring complete 3-D surface models using a single orthographic structured light projector, a pair of planar mirrors, and one or more synchronized cameras. Using the mirrors, we project structured light ... Keywords: 3-D reconstruction, Full object scanning, Gray codes, Orthographic projection, Structured lighting

Douglas Lanman; Daniel Crispell; Gabriel Taubin

2009-11-01T23:59:59.000Z

286

Icon Scanning: Towards Next Generation QR Codes Itamar Friedman  

E-Print Network [OSTI]

Icon Scanning: Towards Next Generation QR Codes Itamar Friedman Technion Haifa, Israel itamarf-friendly way to obtain this particular applica- tion could be by taking a snapshot of its corresponding icon be thought of as icons with a binary pattern. In this paper we extend this to App-icons and propose

Zelnik-Manor, Lihi - Zelnik-Manor, Lihi

287

ProScan IITM 1 Table of Contents  

E-Print Network [OSTI]

an Existing Stage 19 4.2 Fitting the ProScan Stage 19 4.3 Cable Connections 20 4.4 USB Operation 20 4.5 Focus only to designated power sources as marked on the product. · Make sure the electrical cord is located manufacturers overstate thei

Gardel, Margaret

288

A Rapid Scanning Inspection Method for Insulated Ferromagnetic Tubing  

E-Print Network [OSTI]

Until the present there has been no effective way to rapidly scan thermally insulated refinery or process piping for corrosion or thin wall. Such defects, if left unattended, can lead to wasteful losses of time, energy and money. To date the most...

Marsh, G. M.; Milewits, M.

1984-01-01T23:59:59.000Z

289

Nmap in the Enterprise: Your Guide to Network Scanning  

Science Journals Connector (OSTI)

Nmap, or Network Mapper, is a free, open source tool that is available under the GNU General Public License as published by the Free Software Foundation. It is most often used by network administrators and IT security professionals to scan corporate ... Keywords: Networking, Security

Angela Orebaugh; Becky Pinkard

2008-02-01T23:59:59.000Z

290

A novel image hash algorithm resistant to print-scan  

Science Journals Connector (OSTI)

With the rapid development of multimedia technology, how to establish the integrity of images has become an unavoidable problem. The transform between a digital image and its hard-copy makes the problem more complex. To simplify the content based authentication, ... Keywords: Image hashing, Perceptual hashing, Print, Radon, Scan, Wavelet

Di Wu; Xuebing Zhou; Xiamu Niu

2009-12-01T23:59:59.000Z

291

3D Scanning for Biometric Identification and Verification  

E-Print Network [OSTI]

June 2010 3D Scanning for Biometric Identification and Verification Project Leads Anselmo Lastra visibility, cannot be controlled. A relatively new biometric, 3D facial recognition, holds great promise performance using 3D shape and texture matched that of the much more mature technologies of high

McShea, Daniel W.

292

Processing data from scanning gauges on industrial web processes  

Science Journals Connector (OSTI)

This paper considers the processing of data collected by scanning gauges from industrial web processes such as metal rolling, coating, paper making and plastic film extrusion. It describes a method based upon the generalised sampling theorem for reconstructing ... Keywords: Cross-directional control, Gauging, Sampling, Two-dimensional systems, Web processes

Stephen Duncan; Peter Wellstead

2004-03-01T23:59:59.000Z

293

Optics in Brazil  

Science Journals Connector (OSTI)

For Brazilian scientists, optics is considered a leading field in technology transfer. The discipline plays a large role in the country?s ongoing scientific ...

Bagnato, Vanderlei; Brito Cruz, Carlos H de

2006-01-01T23:59:59.000Z

294

LSST Camera Optics Design  

SciTech Connect (OSTI)

The Large Synoptic Survey Telescope (LSST) uses a novel, three-mirror, telescope design feeding a camera system that includes a set of broad-band filters and three refractive corrector lenses to produce a flat field at the focal plane with a wide field of view. Optical design of the camera lenses and filters is integrated in with the optical design of telescope mirrors to optimize performance. We discuss the rationale for the LSST camera optics design, describe the methodology for fabricating, coating, mounting and testing the lenses and filters, and present the results of detailed analyses demonstrating that the camera optics will meet their performance goals.

Riot, V J; Olivier, S; Bauman, B; Pratuch, S; Seppala, L; Gilmore, D; Ku, J; Nordby, M; Foss, M; Antilogus, P; Morgado, N

2012-05-24T23:59:59.000Z

295

Optically measuring interior cavities  

DOE Patents [OSTI]

A method of measuring the three-dimensional volume or perimeter shape of an interior cavity includes the steps of collecting a first optical slice of data that represents a partial volume or perimeter shape of the interior cavity, collecting additional optical slices of data that represents a partial volume or perimeter shape of the interior cavity, and combining the first optical slice of data and the additional optical slices of data to calculate of the three-dimensional volume or perimeter shape of the interior cavity.

Stone, Gary Franklin (Livermore, CA)

2008-12-21T23:59:59.000Z

296

Optical limiting materials  

DOE Patents [OSTI]

Optical limiting materials. 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 400-1100 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.

McBranch, Duncan W. (Santa Fe, NM); Mattes, Benjamin R. (Santa Fe, NM); Koskelo, Aaron C. (Los Alamos, NM); Heeger, Alan J. (Santa Barbara, CA); Robinson, Jeanne M. (Los Alamos, NM); Smilowitz, Laura B. (Los Alamos, NM); Klimov, Victor I. (Los Alamos, NM); Cha, Myoungsik (Goleta, CA); Sariciftci, N. Serdar (Santa Barbara, CA); Hummelen, Jan C. (Groningen, NL)

1998-01-01T23:59:59.000Z

297

Nanotechnology for Optical Networks  

Science Journals Connector (OSTI)

Transparent optical networks will rely on electronics for control and monitoring. Integrating infrared optoelectronic devices such as lasers, modulators, and detectors onto silicon...

Sargent, Edward

298

Transverse Optical Magnetism  

Science Journals Connector (OSTI)

Magnetic interactions with light are usually so small that they are ignored, even in nonlinear optics. Scientists have discovered that parametric processes can drive the interactions...

Rand, Stephen

2010-01-01T23:59:59.000Z

299

Optical contact micrometer  

SciTech Connect (OSTI)

Certain examples provide optical contact micrometers and methods of use. An example optical contact micrometer includes a pair of opposable lenses to receive an object and immobilize the object in a position. The example optical contact micrometer includes a pair of opposable mirrors positioned with respect to the pair of lenses to facilitate viewing of the object through the lenses. The example optical contact micrometer includes a microscope to facilitate viewing of the object through the lenses via the mirrors; and an interferometer to obtain one or more measurements of the object.

Jacobson, Steven D.

2014-08-19T23:59:59.000Z

300

Bioelectrical SPMs (G. Gomila, UB-IBEC) Bioelectric Scanning Probe Microscopies  

E-Print Network [OSTI]

-ups: Micropippete based electrodes Measurements of cell membrane ion transport on single cells 2. Scanning Ion (SNOM),Scanning Tunneling Microscope (STM), Scanning Ion Conductance Microscope (SICM), Scanning Conductance Microscopy #12;7 Bioelectrical SPMs (G. Gomila, UB-IBEC) Single ion channels recordings Average

Ritort, Felix

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

AN INTRODUCTION TO QUANTUM OPTICS...  

E-Print Network [OSTI]

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

Palffy-Muhoray, Peter

302

Optical interferometry at ultra low temperatures  

SciTech Connect (OSTI)

We have developed optical, interferometric methods for investigations of interfaces at ultra low temperatures. In our scheme conventional optical windows are avoided: laser illumination (He-Ne) is guided into the cryostat via a single-mode optical fiber and images are taken using a CCD sensor mounted inside the 4-K vacuum can. A real-time video camera has been successfully used in investigations of superfluid {sup 3}He down to 0.6 mK whereas a slow-scan camera has been employed for optimal contrast in low-intensity imaging of liquid/solid interfaces (reflection coefficient {approximately}10{sup -6}). The investigated topics include (1) superfluid {sup 3}He surface in rotation and during rapid deceleration, (2) hydrodynamics of thin superfluid {sup 3}He layers, (3) superfluid/solid interface in {sup 4}He, and (4) wetting of superfluid {sup 4}He by normal {sup 3}He in phase separated mixtures. A vertical resolution of 10 nm and even below has been achieved in these studies.

Hakonen, P.J.; Alles, H.; Babkin, A.V.; Ruutu, J.P. [Helsinki Univ. of Technology, Espoo (Finland)

1995-10-01T23:59:59.000Z

303

Carbon 41 (2003) 18271831 Optical emission spectroscopy study of the influence of  

E-Print Network [OSTI]

arc discharge, laser ablation, and analyzing optical emissions in the plasma and comparing chemical by an iron oxide film with a aligned CNTs [4,5]. thickness of 50 nm by the sol­gel method [8 characterized by scanning electron micro- increased to 80% o

Zhang, Guangyu

304

Comparison of SEM and Optical Analysis of DT Neutron Tracks in CR-39 Detectors  

SciTech Connect (OSTI)

A solid state nuclear track detector, CR-39, was exposed to DT neutrons. After etching, the resultant tracks were analyzed using both an optical microscope and a scanning electron microscope (SEM). In this communication, both methods of analyzing DT neutron tracks are discussed.

P.A. Mosier-Boss, L.P.G. Forsley, P. Carbonnelle, M.S. Morey, J.R. Tinsley, J. P. Hurley, F.E. Gordon

2012-01-01T23:59:59.000Z

305

Single-element optical injection locking of diode-laser arrays  

DOE Patents [OSTI]

By optically injecting a single end-element of a semiconductor laser array, both the spatial and spectral emission characteristics of the entire laser array is controlled. With the output of the array locked, the far-field emission angle of the array is continuously scanned over several degrees by varying the injection frequency.

Hadley, G. Ronald (Albuquerque, NM); Hohimer, John P. (Albuquerque, NM); Owyoung, Adelbert (Albuquerque, NM)

1988-01-01T23:59:59.000Z

306

High speed two-dimensional optical beam position detector  

SciTech Connect (OSTI)

Disclosed is the design of a high speed two-dimensional optical beam position detector which outputs the X and Y displacement and total intensity linearly. The experimental detector measures the displacement from DC to 123 MHz and the intensity of an optical spot in a similar way as a conventional quadrant photodiode detector. The design uses four discrete photodiodes and simple dedicated optics for the position decomposition which enables higher spatial accuracy and faster electronic processing than conventional detectors. Measurements of the frequency response and the spatial sensitivity demonstrate high suitability for atomic force microscopy, scanning probe data storage applications, and wideband wavefront sensing. The operation principle allows for position measurements up to 20 GHz and more in bandwidth.

Rutten, Paul Edmond [Maypa B.V., Bijsters 2, 5131 NW, Alphen (Netherlands)

2011-07-15T23:59:59.000Z

307

Future of Optical Astronomy  

Science Journals Connector (OSTI)

... I BELIEVE that optical astronomy in Great Britain has now reached, for virtually the first time in its history, ... studied in universities and in Government and industrial laboratories; but with two exceptions, optical astronomy is studied almost entirely in university laboratories only, and its future largely depends on ...

D. E. BLACKWELL

1962-09-01T23:59:59.000Z

308

Optical fuel pin scanner  

DOE Patents [OSTI]

An optical scanner for indicia arranged in a focal plane at a cylindrical outside surface by use of an optical system including a rotatable dove prism. The dove prism transmits a rotating image of an encircled cylindrical surface area to a stationary photodiode array.

Kirchner, Tommy L. (Richland, WA); Powers, Hurshal G. (Richland, WA)

1983-01-01T23:59:59.000Z

309

Vibration insensitive optical cavity  

Science Journals Connector (OSTI)

An optical cavity is designed and implemented that is insensitive to vibration in all directions. The cavity is mounted with its optical axis in the horizontal plane. A minimum response of 0.1 (3.7)kHz?ms?2 is achieved for low-frequency vertical (horizontal) vibrations.

S. A. Webster; M. Oxborrow; P. Gill

2007-01-09T23:59:59.000Z

310

Multimode optical fiber  

DOE Patents [OSTI]

A depressed graded-index multimode optical fiber includes a central core, an inner depressed cladding, a depressed trench, an outer depressed cladding, and an outer cladding. The central core has an alpha-index profile. The depressed claddings limit the impact of leaky modes on optical-fiber performance characteristics (e.g., bandwidth, core size, and/or numerical aperture).

Bigot-Astruc, Marianne; Molin, Denis; Sillard, Pierre

2014-11-04T23:59:59.000Z

311

Fiber optic hydrophone  

DOE Patents [OSTI]

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.

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

1994-01-01T23:59:59.000Z

312

Digital optical conversion module  

DOE Patents [OSTI]

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.

Kotter, Dale K. (North Shelley, ID); Rankin, Richard A. (Ammon, ID)

1991-02-26T23:59:59.000Z

313

Digital optical conversion module  

DOE Patents [OSTI]

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.

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

1988-07-19T23:59:59.000Z

314

Fiber optic hydrophone  

DOE Patents [OSTI]

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.

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

1994-05-10T23:59:59.000Z

315

Growth direction of oblique angle electron beam deposited silicon monoxide thin films identified by optical second-harmonic generation  

SciTech Connect (OSTI)

Oblique angle deposited (OAD) silicon monoxide (SiO) thin films forming tilted columnar structures have been characterized by second-harmonic generation. It was found that OAD SiO leads to a rotationally anisotropic second-harmonic response, depending on the optical angle of incidence. A model for the observed dependence of the second-harmonic signal on optical angle of incidence allows extraction of the growth direction of OAD films. The optically determined growth directions show convincing agreement with cross-sectional scanning electron microscopy images. In addition to a powerful characterization tool, these results demonstrate the possibilities for designing nonlinear optical devices through SiO OAD.

Vejling Andersen, Søren; Lund Trolle, Mads; Pedersen, Kjeld [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, DK-9220 Aalborg Øst (Denmark)] [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, DK-9220 Aalborg Øst (Denmark)

2013-12-02T23:59:59.000Z

316

Phase Stable Net Acceleration of Electrons From a Two-Stage Optical Accelerator  

SciTech Connect (OSTI)

In this article we demonstrate the net acceleration of relativistic electrons using a direct, in-vacuum interaction with a laser. In the experiment, an electron beam from a conventional accelerator is first energy modulated at optical frequencies in an inverse-free-electron-laser and bunched in a chicane. This is followed by a second stage optical accelerator to obtain net acceleration. The optical phase between accelerator stages is monitored and controlled in order to scan the accelerating phase and observe net acceleration and deceleration. Phase jitter measurements indicate control of the phase to {approx}13{sup o} allowing for stable net acceleration of electrons with lasers.

Sears, Christopher M.S.; /SLAC /Munich, Max Planck Inst. Quantenopt.; Colby, Eric; England, R.J.; Ischebeck, Rasmus; McGuinness, Christopher; Nelson, Janice; Noble, Robert; Siemann, Robert H.; Spencer, James; Walz, Dieter; /SLAC; Plettner, Tomas; Byer, Robert L.; /Stanford U., Phys. Dept.

2011-11-11T23:59:59.000Z

317

Optically Interconnected MulticomputersUsing  

E-Print Network [OSTI]

Optically Interconnected MulticomputersUsing Inverted-GraphTopologies Tosuccessfullyexploitthebenefitsofopticaltechnologyinatightlycoupledmulticomputer, the architecturaldesignmust reflectboth the advantages and limitationsof optics. This article systems. Although optics have con- tributed dramatically to long-distance communi- cation and more

Krchnavek, Robert R.

318

Optical amplifier-powered quantum optical amplification  

E-Print Network [OSTI]

I show that an optical amplifier, when combined with photon subtraction, can be used for quantum state amplification, adding noise at a level below the standard minimum. The device could be used to significantly decrease the probability of incorrectly identifying coherent states chosen from a finite set.

John Jeffers

2011-05-16T23:59:59.000Z

319

Instrument Series: Microscopy Aberration-Corrected Scanning/Transmission  

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

Aberration-Corrected Aberration-Corrected Scanning/Transmission Electron Microscope EMSL's aberration-corrected Titan 80-300(tm) scanning/transmission electron microscope (S/TEM) provides high-resolution imaging with sub-angstrom resolution and spectroscopic capabilities. This state-of-the-art instrument is equipped with a Schottky field-emission electron source, an electron gun monochromator, CEOS hexapole spherical aberration corrector for the probe-forming lens, high-angle annular dark field (HAADF) detector, an X-ray spectrometer (EDS), and a high-resolution Gatan Imaging Filter (GIF). The selection of electron energy between 80 kV and 300 kV enables optimized imaging for a variety of samples, including electron beam sensitive materials. Research Applications

320

Instrument Series: Microscopy Ultra-High Vacuum, Low- Temperature Scanning  

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

Low- Low- Temperature Scanning Probe Microscope EMSL's ultra-high vacuum, low-temperature scanning probe microscope instrument, or UHV LT SPM, is the preeminent system dedicated to surface chemistry and physics at low temperatures down to 5 K. Operating at low temperatures provides high mechanical stability, superior vacuum conditions, and negligible drift for long-term experiments. With thermal diffusion being entirely suppressed, stable imaging becomes possible even for weakly bound species. The system is primarily used for probing single-site chemical reactivity, while the combination with a hyperthermal molecular beam allows the study of important chemical processes at energies corresponding to the operational temperatures well beyond typical UHV studies. The LT SPM provides

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Monte Carlo simulation of gamma ray scanning gauge  

SciTech Connect (OSTI)

A gamma ray scanning gauge was simulated with Monte Carlo to study the properties of gamma scanning gauges and to resolve the counts coming from a {sup 235}U source from those coming from a contaminant ({sup 232}U) whose daughters emit high energy gamma rays. The simulation has been used to infer the amount of the {sup 232}U contaminant in a {sup 235}U source to select the best size for the NaI(Tl) detector crystal to minimize the effect of the contaminant. The results demonstrate that Monte Carlo simulation provides a systematic tool for designing a gauge with desired properties and for estimating properties of the gamma source from measured count rates.

Hartfield, G.L.; Freeman, L.B.; Dei, D.E.; Emert, C.J.; Glickstein, S.S.; Kahler, A.C.; Niedzwecki, P.F.

1990-12-31T23:59:59.000Z

322

Synchronized monochromator and insertion device energy scans at SLS  

SciTech Connect (OSTI)

Synchronous monochromator and insertion device energy scans were implemented at the Surfaces/Interfaces:Microscopy (SIM) beamline in order to provide the users fast X-ray magnetic dichroism studies (XMCD). A simple software control scheme is proposed based on a fast monochromator run-time energy readback which quickly updates the insertion device requested energy during an on-the-fly X-ray absorption scan (XAS). In this scheme the Plain Grating Monochromator (PGM) motion control, being much slower compared with the insertion device (APPLE-II type undulator), acts as a 'master' controlling the undulator 'slave' energy position. This master-slave software implementation exploits EPICS distributed device control over computer network and allows for a quasi-synchronous motion control combined with data acquisition needed for the XAS or XMCD experiment.

Krempasky, J.; Flechsig, U.; Korhonen, T.; Zimoch, D.; Quitmann, Ch.; Nolting, F. [Paul Scherrer Institut, Villigen, Swiss Light Source, 5235 Villigen PSI (Switzerland)

2010-06-23T23:59:59.000Z

323

Measurement of Semiconductor Surface Potential using the Scanning Electron Microscope  

SciTech Connect (OSTI)

We calibrate the secondary electron signal from a standard scanning electron microscope to voltage, yielding an image of the surface or near-surface potential. Data on both atomically abrupt heterojunction GaInP/GaAs and diffused homojunction Si solar cell devices clearly show the expected variation in potential with position and applied bias, giving depletion widths and locating metallurgical junctions to an accuracy better than 10 nm. In some images, distortion near the p-n junction is observed, seemingly consistent with the effects of lateral electric fields (patch fields). Reducing the tube bias removes this distortion. This approach results in rapid and straightforward collection of near-surface potential data using a standard scanning electron microscope.

Heath, J. T.; Jiang, C. S.; Al-Jassim, M. M.

2012-02-15T23:59:59.000Z

324

Metastatic cardiac tumor demonstrated by 201 thallium scan  

SciTech Connect (OSTI)

A patient with bronchogenic carcinoma had an electrocardiogram that was initially thought to be consistent with myocardial infarction and possible left ventricular aneurysm. A heart scan with radioactive 201 thallium showed an area of sharply diminished uptake cold spot; however, subsequent thoracotomy showed that this was caused by local pericardial and myocardial infiltration by tumor. This suggests a role for radioactive 201 thallium in the detection of cardiac metastatic tumors.

Lubell, D.L.; Goldfarb, C.R.

1980-07-01T23:59:59.000Z

325

Science, Optics and You: Shadows  

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

http:micro.magnet.fsu.eduopticstutorialsindex.html INTRODUCTION SHADOWS MODULE m5 SCIENCE, OPTICS & YOU GUIDEBOOK - 96 - SCIENCE, OPTICS & YOU GUIDEBOOK - 97 - m5: Shadows...

326

Optical Modulation of Molecular Conductance  

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

Optical Modulation of Molecular Conductance Authors: Battacharyya, S., Kibel, A., Kodis, G., Liddell, P. A., Gervaldo, M., Gust, D., and Lindsay, S. Title: Optical Modulation of...

327

Enhancing DNA binding rate using optical trapping of high-density gold nanodisks  

SciTech Connect (OSTI)

We present the dynamic study of optical trapping of fluorescent molecules using high-density gold nanodisk arrays. The gold nanodisks were fabricated by electron beam lithography with a diameter of 500 nm and a period of 1 ?m. Dark-field illumination showed ?15 times enhancement of fluorescence near edges of nanodisks. Such enhanced near-field generated an optical trapping force of ?10 fN under 3.58 × 10{sup 3} W/m{sup 2} illumination intensity as calculated from the Brownian motions of 590 nm polystyrene beads. Kinetic observation of thiolated DNA modified with Cy5 dye showed different binding rates of DNA under different illumination intensity. The binding rate increased from 2.14 × 10{sup 3} s{sup ?1} (I = 0.7 × 10{sup 3} W/m{sup 2}) to 1.15 × 10{sup 5} s{sup ?1} (I = 3.58 × 10{sup 3} W/m{sup 2}). Both enhanced fluorescence and binding rate indicate that gold nanodisks efficiently improve both detection limit and interaction time for microarrays.

Lin, En-Hung; Pan, Ming-Yang [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China) [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China); Lee, Ming-Chang [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China)] [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Wei, Pei-Kuen, E-mail: pkwei@sinica.edu.tw [Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China) [Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China); Institute of Biophotonics, National Yang-Ming University, Taipei 11221, Taiwan (China)

2014-03-15T23:59:59.000Z

328

A novel solid-angle tomosynthesis (SAT) scanning scheme  

SciTech Connect (OSTI)

Purpose: Digital tomosynthesis (DTS) recently gained extensive research interests in both diagnostic and radiation therapy fields. Conventional DTS images are generated by scanning an x-ray source and flat-panel detector pair on opposite sides of an object, with the scanning trajectory on a one-dimensional curve. A novel tomosynthesis method named solid-angle tomosynthesis (SAT) is proposed, where the x-ray source scans on an arbitrary shaped two-dimensional surface. Methods: An iterative algorithm in the form of total variation regulated expectation maximization is developed for SAT image reconstruction. The feasibility and effectiveness of SAT is corroborated by computer simulation studies using three-dimensional (3D) numerical phantoms including a 3D Shepp-Logan phantom and a volumetric CT image set of a human breast. Results: SAT is able to cover more space in Fourier domain more uniformly than conventional DTS. Greater coverage and more isotropy in the frequency domain translate to fewer artifacts and more accurately restored features in the in-plane reconstruction. Conclusions: Comparing with conventional DTS, SAT allows cone-shaped x-ray beams to project from more solid angles, thus provides more coverage in the spatial-frequency domain, resulting in better quality of reconstructed image.

Zhang Jin; Yu, Cedric [Department of Radiation Oncology, University of Maryland School of Medicine, 22 S. Greene Street, Baltimore, Maryland 21201 and Xcision Medical System, LLC, 12707 Chapel Chase Drive, Clarksville, Maryland 21209 (United States)

2010-08-15T23:59:59.000Z

329

Alignment and Aperture Scan at the Fermilab Booster  

SciTech Connect (OSTI)

The Fermilab Booster is currently in the process of an intensity upgrade referred to as the Proton Improvement Plan (PIP). The goal of PIP is to have the Booster provide a proton beam flux of 2 x 10{sup 17} protons/hour. This is almost double the current operation of 1.1 x 10{sup 17} protons/hour. Beam losses in the machine due to the increased flux will create larger integrated doses on aperture limiting components that will need to be mitigated. The Booster accelerates beam from 400 MeV to 8 GeV at a rep rate of 15hz and then extracts beam to the Main Injector. Several percent of the beam is lost within 3 msec after injection in the early part of acceleration. The aperture at injection energy was recently measured using corrector scans. Along with magnet survey data and aperture scan data a plan to realign the magnets in the Booster was developed and implemented in May 2012. The beam studies, analysis of the scan and alignment data, and the result of the magnet moves are presented.

Seiya, K.; Lackey, J.; Marsh, W.; Pellico, W.; Still, D.; Triplet, K.; Waller, A.; /Fermilab

2012-05-01T23:59:59.000Z

330

Gregorian optical system with non-linear optical technology for protection against intense optical transients  

DOE Patents [OSTI]

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.

Ackermann, Mark R. (Albuquerque, NM); Diels, Jean-Claude M. (Albuquerque, NM)

2007-06-26T23:59:59.000Z

331

Silicon fiber optic sensors  

DOE Patents [OSTI]

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%.

Pocha, Michael D. (Livermore, CA); Swierkowski, Steve P. (Livermore, CA); Wood, Billy E. (Livermore, CA)

2007-10-02T23:59:59.000Z

332

Optical Quadratic Measure Eigenmodes  

E-Print Network [OSTI]

We report a mathematically rigorous technique which facilitates the optimization of various optical properties of electromagnetic fields. The technique exploits the linearity of electromagnetic fields along with the quadratic nature of their interaction with matter. In this manner we may decompose the respective fields into optical quadratic measure eigenmodes (QME). Key applications include the optimization of the size of a focused spot, the transmission through photonic devices, and the structured illumination of photonic and plasmonic structures. We verify the validity of the QME approach through a particular experimental realization where the size of a focused optical field is minimized using a superposition of Bessel beams.

Michael Mazilu; Joerg Baumgartl; Sebastian Kosmeier; Kishan Dholakia

2010-07-13T23:59:59.000Z

333

Fiber optic laser rod  

DOE Patents [OSTI]

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.

Erickson, G.F.

1988-04-13T23:59:59.000Z

334

Tuned optical cavity magnetometer  

DOE Patents [OSTI]

An atomic magnetometer is disclosed which utilizes an optical cavity formed from a grating and a mirror, with a vapor cell containing an alkali metal vapor located inside the optical cavity. Lasers are used to magnetically polarize the alkali metal vapor and to probe the vapor and generate a diffracted laser beam which can be used to sense a magnetic field. Electrostatic actuators can be used in the magnetometer for positioning of the mirror, or for modulation thereof. Another optical cavity can also be formed from the mirror and a second grating for sensing, adjusting, or stabilizing the position of the mirror.

Okandan, Murat (Edgewood, NM); Schwindt, Peter (Albuquerque, NM)

2010-11-02T23:59:59.000Z

335

Optical Third-Harmonic Generation in Graphene  

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

We report strong third-harmonic generation in monolayer graphene grown by chemical vapor deposition and transferred to an amorphous silica (glass) substrate; the photon energy is in three-photon resonance with the exciton-shifted van Hove singularity at the M point of graphene. The polarization selection rules are derived and experimentally verified. In addition, our polarization- and azimuthal-rotation-dependent third-harmonic-generation measurements reveal in-plane isotropy as well as anisotropy between the in-plane and out-of-plane nonlinear optical responses of graphene. Since the third-harmonic signal exceeds that from bulk glass by more than 2 orders of magnitude, the signal contrast permits background-free scanning of graphene and provides insight into the structural properties of graphene.

Hong, Sung-Young; Dadap, Jerry I.; Petrone, Nicholas; Yeh, Po-Chun; Hone, James; Osgood, Richard M.

2013-06-01T23:59:59.000Z

336

Jessen/Deutsch, "Optical Lattices" 1 OPTICAL LATTICES  

E-Print Network [OSTI]

Jessen/Deutsch, "Optical Lattices" 1 OPTICAL LATTICES P. S. JESSEN Optical Sciences Center@rhea.opt-sci.arizona.edu I. H. DEUTSCH Center for Advanced Studies University of New Mexico Albuquerque, NM, 87131 Phone, 1996). #12;Jessen/Deutsch, "Optical Lattices" 2 CONTENTS I. Introduction

Jessen, Poul S.

337

Surface plasmon enhanced third-order optical nonlinearity of Ag nanocomposite film  

SciTech Connect (OSTI)

We obtain a large third-order optical nonlinearity (?{sup (3)}???10{sup ?10}esu) of silver nanoparticles dispersed in polyvinyl alcohol/tetraethyl orthosilicate matrix using single beam z-scan technique at 532?nm by Q-switched Nd:YAG laser. We have shown that mechanisms responsible for third-order optical nonlinearity of Ag nanocomposite film are reverse saturable absorption (RSA) and self-defocusing in the purlieu of surface plasmon resonance (SPR). Optical band-gap and width of SPR band of Ag nanocomposite film decrease with increasing silver concentration, which leads to enhancement of local electric field and hence third-order optical nonlinearity. Optical limiting, due to RSA has also been demonstrated at 532?nm.

Singh, Vijender [Department of Applied Science, N.C. College of Engineering, Israna, Panipat 132107, Haryana (India); Aghamkar, Praveen, E-mail: p-aghamkar@yahoo.in [Department of Physics, Chaudhary Devi Lal University, Sirsa 125055, Haryana (India)

2014-03-17T23:59:59.000Z

338

CT head-scan dosimetry in an anthropomorphic phantom and associated measurement of ACR accreditation-phantom imaging metrics under clinically representative scan conditions  

SciTech Connect (OSTI)

Purpose: To measure radiation absorbed dose and its distribution in an anthropomorphic head phantom under clinically representative scan conditions in three widely used computed tomography (CT) scanners, and to relate those dose values to metrics such as high-contrast resolution, noise, and contrast-to-noise ratio (CNR) in the American College of Radiology CT accreditation phantom.Methods: By inserting optically stimulated luminescence dosimeters (OSLDs) in the head of an anthropomorphic phantom specially developed for CT dosimetry (University of Florida, Gainesville), we measured dose with three commonly used scanners (GE Discovery CT750 HD, Siemens Definition, Philips Brilliance 64) at two different clinical sites (Walter Reed National Military Medical Center, National Institutes of Health). The scanners were set to operate with the same data-acquisition and image-reconstruction protocols as used clinically for typical head scans, respective of the practices of each facility for each scanner. We also analyzed images of the ACR CT accreditation phantom with the corresponding protocols. While the Siemens Definition and the Philips Brilliance protocols utilized only conventional, filtered back-projection (FBP) image-reconstruction methods, the GE Discovery also employed its particular version of an adaptive statistical iterative reconstruction (ASIR) algorithm that can be blended in desired proportions with the FBP algorithm. We did an objective image-metrics analysis evaluating the modulation transfer function (MTF), noise power spectrum (NPS), and CNR for images reconstructed with FBP. For images reconstructed with ASIR, we only analyzed the CNR, since MTF and NPS results are expected to depend on the object for iterative reconstruction algorithms.Results: The OSLD measurements showed that the Siemens Definition and the Philips Brilliance scanners (located at two different clinical facilities) yield average absorbed doses in tissue of 42.6 and 43.1 mGy, respectively. The GE Discovery delivers about the same amount of dose (43.7 mGy) when run under similar operating and image-reconstruction conditions, i.e., without tube current modulation and ASIR. The image-metrics analysis likewise showed that the MTF, NPS, and CNR associated with the reconstructed images are mutually comparable when the three scanners are run with similar settings, and differences can be attributed to different edge-enhancement properties of the applied reconstruction filters. Moreover, when the GE scanner was operated with the facility's scanner settings for routine head exams, which apply 50% ASIR and use only approximately half of the 100%-FBP dose, the CNR of the images showed no significant change. Even though the CNR alone is not sufficient to characterize the image quality and justify any dose reduction claims, it can be useful as a constancy test metric.Conclusions: This work presents a straightforward method to connect direct measurements of CT dose with objective image metrics such as high-contrast resolution, noise, and CNR. It demonstrates that OSLD measurements in an anthropomorphic head phantom allow a realistic and locally precise estimation of magnitude and spatial distribution of dose in tissue delivered during a typical CT head scan. Additional objective analysis of the images of the ACR accreditation phantom can be used to relate the measured doses to high contrast resolution, noise, and CNR.

Brunner, Claudia C.; Stern, Stanley H.; Chakrabarti, Kish [U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States)] [U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States); Minniti, Ronaldo [National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899 (United States)] [National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899 (United States); Parry, Marie I. [Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda, Maryland 20889 (United States)] [Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda, Maryland 20889 (United States); Skopec, Marlene [National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892 (United States)] [National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892 (United States)

2013-08-15T23:59:59.000Z

339

Optical Landau damping  

SciTech Connect (OSTI)

We study the transfer of energy from an optical potential to atomic and molecular gases and demonstrate that this process is analogous to collisionless Landau damping of electrostatic potentials in plasmas and gravitational potentials observed on astrophysical scales. We show that a signficant fraction of the light attenuation within a cavity can be attributed to this mechanism when the cavity is filled with a gas at high density. The resulting motion of particles created by optical Landau damping can be used to induce transport when a periodic potential produced by two counterpropagating high-intensity pulsed optical fields is used. Bulk drift of the gas also appears feasible even when the mean kinetic energy is much greater that the maximum optical potential.

Shneider, M.N.; Barker, P.F. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Department of Physics, School of Engineering and Physical Sciences, Heriott-Watt University, Edinburgh EH14 4AS, Scotland (United Kingdom)

2005-05-15T23:59:59.000Z

340

Cryogenic optical refrigeration.  

E-Print Network [OSTI]

??This thesis compiles recent achievements in optical refrigeration, cooling a 5 wt. % ytterbium doped yttrium lithium fluoride (Yb+3:YLF) crystal through anti-Stokes fluorescence to a… (more)

Melgaard, Seth

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Intracoronary Optical Diagnostics  

E-Print Network [OSTI]

Optical coherence tomography (OCT), is a novel intravascular imaging modality analogous to intravascular ultrasound but uses light instead of sound. This review details the background, development, and status of current ...

Lowe, Harry C.

342

Optical displacement sensor  

DOE Patents [OSTI]

An optical displacement sensor is disclosed which uses a vertical-cavity surface-emitting laser (VCSEL) coupled to an optical cavity formed by a moveable membrane and an output mirror of the VCSEL. This arrangement renders the lasing characteristics of the VCSEL sensitive to any movement of the membrane produced by sound, vibrations, pressure changes, acceleration, etc. Some embodiments of the optical displacement sensor can further include a light-reflective diffractive lens located on the membrane or adjacent to the VCSEL to control the amount of lasing light coupled back into the VCSEL. A photodetector detects a portion of the lasing light from the VCSEL to provide an electrical output signal for the optical displacement sensor which varies with the movement of the membrane.

Carr, Dustin W. (Albuquerque, NM)

2008-04-08T23:59:59.000Z

343

Optical Quantum Computing  

E-Print Network [OSTI]

In 2001 all-optical quantum computing became feasible with the discovery that scalable quantum computing is possible using only single photon sources, linear optical elements, and single photon detectors. Although it was in principle scalable, the massive resource overhead made the scheme practically daunting. However, several simplifications were followed by proof-of-principle demonstrations, and recent approaches based on cluster states or error encoding have dramatically reduced this worrying resource overhead, making an all-optical architecture a serious contender for the ultimate goal of a large-scale quantum computer. Key challenges will be the realization of high-efficiency sources of indistinguishable single photons, low-loss, scalable optical circuits, high efficiency single photon detectors, and low-loss interfacing of these components.

Jeremy L. O'Brien

2008-03-11T23:59:59.000Z

344

Stereoscopic optical viewing system  

DOE Patents [OSTI]

An improved optical system which provides the operator with a stereoscopic viewing field and depth of vision, particularly suitable for use in various machines such as electron or laser beam welding and drilling machines. The system features two separate but independently controlled optical viewing assemblies from the eyepiece to a spot directly above the working surface. Each optical assembly comprises a combination of eye pieces, turning prisms, telephoto lenses for providing magnification, achromatic imaging relay lenses and final stage pentagonal turning prisms. Adjustment for variations in distance from the turning prisms to the workpiece, necessitated by varying part sizes and configurations and by the operator's visual accuity, is provided separately for each optical assembly by means of separate manual controls at the operator console or within easy reach of the operator.

Tallman, C.S.

1986-05-02T23:59:59.000Z

345

Optical gamma thermometer  

DOE Patents [OSTI]

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.

Koster, Glen Peter; Xia, Hua; Lee, Boon Kwee

2013-08-06T23:59:59.000Z

346

Absorbance modulation optical lithography  

E-Print Network [OSTI]

In this thesis, the concept of absorbance-modulation optical lithography (AMOL) is described, and the feasibility experimentally verified. AMOL is an implementation of nodal lithography, which is not bounded by the diffraction ...

Tsai, Hsin-Yu Sidney

2007-01-01T23:59:59.000Z

347

Fiber optic fluid detector  

DOE Patents [OSTI]

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.

Angel, S.M.

1987-02-27T23:59:59.000Z

348

Electro-Optical Characterization  

SciTech Connect (OSTI)

In the Electro-Optical Characterization group, within the National Center for Photovoltaic's Measurements and Characterization Division, we use various electrical and optical experimental techniques to relate photovoltaic device performance to the methods and materials used to produce them. The types of information obtained by these techniques range from small-scale atomic-bonding information to large-scale macroscopic quantities such as optical constants and electron-transport properties. Accurate and timely measurement of the electro-optical properties as a function of device processing provides researchers and manufacturers with the knowledge needed to troubleshoot problems and develop the knowledge base necessary for reducing cost, maximizing efficiency, improving reliability, and enhancing manufacturability. We work collaboratively with you to solve materials- and device-related R&D problems. This sheet summarizes our primary techniques and capabilities.

Not Available

2006-06-01T23:59:59.000Z

349

Optical Quantum Computation  

E-Print Network [OSTI]

We review the field of Optical Quantum Computation, considering the various implementations that have been proposed and the experimental progress that has been made toward realizing them. We examine both linear and nonlinear approaches and both particle and field encodings. In particular we discuss the prospects for large scale optical quantum computing in terms of the most promising physical architectures and the technical requirements for realizing them.

T. C. Ralph; G. J. Pryde

2011-03-31T23:59:59.000Z

350

Relaying an optical wavefront  

DOE Patents [OSTI]

A wavefront rely devices samples an incoming optical wavefront at different locations, optically relays the samples while maintaining the relative position of the samples and the relative phase between the samples. The wavefront is reconstructed due to interference of the samples. Devices can be designed for many different wavelengths, including for example the ultraviolet, visible, infrared and even longer wavelengths such as millimeter waves. In one application, the device function as a telescope but with negligible length.

Sweatt, William C. (Albuquerque, NM); Vawter, G. Allen (Corrales, NM)

2007-03-06T23:59:59.000Z

351

Fault location in optical networks  

DOE Patents [OSTI]

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.

Stevens, Rick C. (Apple Valley, MN); Kryzak, Charles J. (Mendota Heights, MN); Keeler, Gordon A. (Albuquerque, NM); Serkland, Darwin K. (Albuquerque, NM); Geib, Kent M. (Tijeras, NM); Kornrumpf, William P. (Schenectady, NY)

2008-07-01T23:59:59.000Z

352

Optical computing Damien Woods a  

E-Print Network [OSTI]

Optical computing Damien Woods a aDepartment of Computer Science and Artificial Intelligence Institute, Vierimaantie 5, 84100 Ylivieska, Finland Abstract In this survey we consider optical computers of such optical computing archi- tectures, including descriptions of the type of hardware commonly used in optical

Woods, Damien

353

Optical Solitons and their applications  

E-Print Network [OSTI]

Optical Solitons and their applications By: Mohammad Nopoush Supervisor: Professor Palffy-Muhoray #12;Definition Optical: Non-changing optical field during propagation due to delicate balance between nonlinear and linear effects. Nonlinear effects: Due to the optical Kerr effect (AC Kerr effect

Palffy-Muhoray, Peter

354

Undergraduate Handbook Dear Optics student,  

E-Print Network [OSTI]

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

Cantlon, Jessica F.

355

Embedded fiducials in optical surfaces  

DOE Patents [OSTI]

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.

Sommargren, Gary E. (Santa Cruz, CA)

2000-01-01T23:59:59.000Z

356

Observation of diamond turned OFHC copper using Scanning Tunneling Microscopy  

SciTech Connect (OSTI)

Diamond turned OFHC copper samples have been observed within the past few months using the Scanning Tunneling Microscope. Initial results have shown evidence of artifacts which may be used to better understand the diamond turning process. The STM`s high resolution capability and three dimensional data representation allows observation and study of surface features unobtainable with conventional profilometry systems. Also, the STM offers a better quantitative means by which to analyze surface structures than the SEM. This paper discusses findings on several diamond turned OFHC copper samples having different cutting conditions. Each sample has been cross referenced using STM and SEM.

Grigg, D.A.; Russell, P.E.; Dow, T.A.

1988-12-01T23:59:59.000Z

357

E-Print Network 3.0 - analysing laser-scanned digital Sample...  

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

laser-scanned digital Search Powered by Explorit Topic List Advanced Search Sample search results for: analysing laser-scanned digital Page: << < 1 2 3 4 5 > >> 1 This special...

358

Knowledge and heuristic-based modeling of laser-scanned trees  

Science Journals Connector (OSTI)

We present a semi-automatic and efficient method for producing full polygonal models of range scanned trees, which are initially represented as sparse ... Keywords: Digitizing and scanning, knowledge-based modeling

Hui Xu; Nathan Gossett; Baoquan Chen

2007-10-01T23:59:59.000Z

359

Development of a microfluidic device for patterning multiple species by scanning probe lithography  

E-Print Network [OSTI]

Scanning Probe Lithography (SPL) is a versatile nanofabrication platform that leverages microfluidic “ink” delivery systems with Scanning Probe Microscopy (SPM) for generating surface-patterned chemical functionality on the sub-100 nm length scale...

Rivas Cardona, Juan Alberto

2009-06-02T23:59:59.000Z

360

E-Print Network 3.0 - applied optical metrology Sample Search...  

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

Optical Sciences Summary: Research - Quantum Optics Applied Optics & Photonics - Optoelectronics - Optical Communications - Medical... Optics Engineering - Optical System Design...

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF OPTICS A: PURE AND APPLIED OPTICS Polarization Optics  

E-Print Network [OSTI]

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

Friesem, Asher A.

362

Evaluation of hole quality and bit life in graphite epoxy composites using video scanning  

E-Print Network [OSTI]

scanning, (6) penetrant (conventional), (7) infrared scanning, and six other methods. It appears that flouroscopy is the most promising method developed to date. Video scan- ning was rated fifth because it is not effective as the sole criterion for edge... inspection, (3) the surface flaw area as determined by video scanning, (4) the size of entrance delaminations by manual inspection, (5) the maximum wear land development of the drill bits, (6) the average wear land development of the drill bits, (7...

Lednicky, Thomas Edward

2012-06-07T23:59:59.000Z

363

LASER SCANNING AND NOISE REDUCTION APPLIED TO 3D ROAD SURFACE ANALYSIS  

E-Print Network [OSTI]

LASER SCANNING AND NOISE REDUCTION APPLIED TO 3D ROAD SURFACE ANALYSIS Thorsten Schulz and Hilmar, EAWAG Email: michele.steiner@eawag.ch Abstract: Terrestrial laser scanning was applied to acquire 3D the catchment area of a road with respect to a pilot plant. As laser scanning requires only a few minutes

Giger, Christine

364

Improving the detection ...1 Improving the detection of On-line Vertical Port Scan  

E-Print Network [OSTI]

Improving the detection ...1 Improving the detection of On-line Vertical Port Scan Improving the detection of On-line Vertical Port Scan in IP Traffic Yousra Chabchoub , Christine Fricker and Philippe to detect port scan attacks in IP traffic. Only relevant information about destination IP addresses

Paris-Sud XI, Université de

365

Inserting Test Points to Control Peak Power During Scan Testing Ranganathan Sankaralingam and Nur A. Touba  

E-Print Network [OSTI]

simply reducing the average power dissipation per clock cycle. Proceedings of the 17th IEEE International. The average power dissipation during scan testing can be controlled by reducing the scan frequency. However, the peak power during scan testing cannot be controlled by reducing clock frequency and hence is more

Touba, Nur A.

366

On the selection of a partial scan path with respect to target faults  

Science Journals Connector (OSTI)

Today the most often applied DFT-strategy is full scan path. To reduce its overhead a partial scan path can be selected. For minimizing the size of the partial scan path, existing testpatterns are used which will detect a part of the faults. Only the ...

Harald Gundlach; Bernd Koch; Klaus-Dieter Müller-Glaser

1991-02-01T23:59:59.000Z

367

Low-cost wearable low-vision aid using a handmade retinal light-scanning microdisplay  

E-Print Network [OSTI]

scanning fiber display6 to present icons indicating the location of potential hazards. The scanning fiberLow-cost wearable low-vision aid using a handmade retinal light-scanning microdisplay Ryland C) is a portable system that uses machine vision to track potential walking hazards for the visually impaired

Washington at Seattle, University of

368

Scanning x-ray microdiffraction with submicron white beam for strain and orientation mapping in thin films  

SciTech Connect (OSTI)

Scanning X-ray Microdiffraction (m-SXRD) combines the use of high brilliance synchrotron sources with the latest achromatic X-ray focusing optics and fast large area 2D-detector technology. Using white beams or a combination of white and monochromatic beams, it allows for orientation and strain/stress mapping of polycrystalline thin films with submicron spatial resolution. The technique is described in detail as applied to the study of thin aluminium and copper blanket films and lines following electromigration testing and/or thermal cycling experiments. It is shown that there are significant orientation and strain/stress variations between grains and inside individual grains. A polycrystalline film when investigated at the granular (micron) level shows a highly mechanically inhomogeneous medium that allows insight into its mesoscopic properties. If the m-SXRD data are averaged over a macroscopic range, results show good agreement with direct macroscopic texture and stress measurements .

Tamura, N.; MacDowell, A.A.; Spolenak, R.; Valek, B.C.; Bravman, J.C.; Brown, W.L.; Celestre, R.S.; Padmore, H.A.; Batterman, B.W.; Patel, J.R.

2003-01-14T23:59:59.000Z

369

Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect (OSTI)

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.

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.

2013-11-13T23:59:59.000Z

370

Fiber optic hydrogen sensor  

DOE Patents [OSTI]

An 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.

Buchanan, Bruce R. (1985 Willis, Batesburg, SC 29006); Prather, William S. (2419 Dickey Rd., Augusta, GA 30906)

1992-01-01T23:59:59.000Z

371

Optical high acidity sensor  

DOE Patents [OSTI]

An apparatus and method for determining acid concentrations in solutions having acid concentrations of from about 0.1 Molar to about 16 Molar is disclosed. The apparatus includes a chamber for interrogation of the sample solution, a fiber optic light source for passing light transversely through the chamber, a fiber optic collector for receiving the collimated light after transmission through the chamber, a coating of an acid resistant polymeric composition upon at least one fiber end or lens, the polymeric composition in contact with the sample solution within the chamber and having a detectable response to acid concentrations within the range of from about 0.1 Molar to about 16 Molar, a measurer for the response of the polymeric composition in contact with the sample solution, and, a comparer of the measured response to predetermined standards whereby the acid molarity of the sample solution within the chamber can be determined. Preferably, a first lens is attached to the end of the fiber optic light source, the first lens adapted to collimate light from the fiber optic light source, and a second lens is attached to the end of the fiber optic collector for focusing the collimated light after transmission through the chamber.

Jorgensen, Betty S. (Jemez Springs, NM); Nekimken, Howard L. (Los Alamos, NM); Carey, W. Patrick (Lynnwood, WA); O'Rourke, Patrick E. (Martinez, GA)

1997-01-01T23:59:59.000Z

372

Fiber optic hydrogen sensor  

DOE Patents [OSTI]

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.

Buchanan, B.R.; Prather, W.S.

1991-01-01T23:59:59.000Z

373

Fiber optic hydrogen sensor  

DOE Patents [OSTI]

An apparatus and method are described 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. 4 figs.

Buchanan, B.R.; Prather, W.S.

1992-10-06T23:59:59.000Z

374

Combined low-temperature scanning tunneling/atomic force microscope for atomic resolution imaging and site-specific force spectroscopy  

SciTech Connect (OSTI)

The authors present the design and first results of a low-temperature, ultrahigh vacuum scanning probe microscope enabling atomic resolution imaging in both scanning tunneling microscopy (STM) and noncontact atomic force microscopy (NC-AFM) modes. A tuning-fork-based sensor provides flexibility in selecting probe tip materials, which can be either metallic or nonmetallic. When choosing a conducting tip and sample, simultaneous STM/NC-AFM data acquisition is possible. Noticeable characteristics that distinguish this setup from similar systems providing simultaneous STM/NC-AFM capabilities are its combination of relative compactness (on-top bath cryostat needs no pit), in situ exchange of tip and sample at low temperatures, short turnaround times, modest helium consumption, and unrestricted access from dedicated flanges. The latter permits not only the optical surveillance of the tip during approach but also the direct deposition of molecules or atoms on either tip or sample while they remain cold. Atomic corrugations as low as 1 pm could successfully be resolved. In addition, lateral drifts rates of below 15 pm/h allow long-term data acquisition series and the recording of site-specific spectroscopy maps. Results obtained on Cu(111) and graphite illustrate the microscope's performance.

Schwarz, Udo; Albers, Boris J.; Liebmann, Marcus; Schwendemann, Todd C.; Baykara, Mehmet Z.; Heyde, Markus; Salmeron, Miquel; Altman, Eric I.; Schwarz, Udo D.

2008-02-27T23:59:59.000Z

375

Optical quantum memory  

E-Print Network [OSTI]

Quantum memory is important to quantum information processing in many ways: a synchronization device to match various processes within a quantum computer, an identity quantum gate that leaves any state unchanged, and a tool to convert heralded photons to photons-on-demand. In addition to quantum computing, quantum memory would be instrumental for the implementation of long-distance quantum communication using quantum repeaters. The importance of this basic quantum gate is exemplified by the multitude of optical quantum memory mechanisms being studied: optical delay lines, cavities, electromagnetically-induced transparency, photon-echo, and off-resonant Faraday interaction. Here we report on the state-of-the-art in the field of optical quantum memory, including criteria for successful quantum memory and current performance levels.

A. I. Lvovsky; B. C. Sanders; W. Tittel

2010-02-24T23:59:59.000Z

376

Probing graphene defects and estimating graphene quality with optical microscopy  

SciTech Connect (OSTI)

We report a simple and accurate method for detecting graphene defects that utilizes the mild, dry annealing of graphene/Cu films in air. In contrast to previously reported techniques, our simple approach with optical microscopy can determine the density and degree of dislocation of defects in a graphene film without inducing water-related damage or functionalization. Scanning electron microscopy, confocal Raman and atomic force microscopy, and X-ray photoelectron spectroscopy analysis were performed to demonstrate that our nondestructive approach to characterizing graphene defects with optimized thermal annealing provides rapid and comprehensive determinations of graphene quality.

Lai, Shen [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); Kyu Jang, Sung [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Jae Song, Young, E-mail: yjsong@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Department of Physics, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of); Lee, Sungjoo, E-mail: leesj@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); College of Information and Communication Engineering, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of)

2014-01-27T23:59:59.000Z

377

Solvothermal synthesis and study of nonlinear optical properties of nanocrystalline thallium doped bismuth telluride  

SciTech Connect (OSTI)

Nanocrystalline Bismuth telluride and thallium (4 mol %) doped Bismuth telluride were synthesized through hydrothermal method. The as-prepared products were characterized using Powder X-ray Diffraction, High Resolution Transmission Electron Microscopy, Energy Dispersive X-Ray Spectroscopy, UV-Visible spectroscopy and Fourier Transform Infrared Spectroscopy. Powder XRD results revealed the crystalline nature of the obtained phases. HRTEM showed the particle-like morphology of the products. The decrease in the absorption coefficient due to thallium doping was observed in FTIR spectra. The intensity dependent nonlinear optical properties of nanocrystalline bismuth telluride and thallium doped bismuth telluride were studied using the Z-scan technique in open-aperture configuration. Bismuth telluride doped with thallium showed enhanced nonlinear optical response compared to pristine bismuth telluride and hence could be used as a potential candidate for optical power limiting applications. - Graphical Abstract: Nonlinear transmission (Z-scan) curves of nanocrystalline bismuth telluride ({Delta}) and thallium doped bismuth telluride ({open_square}). Thallium doped bismuth telluride showed enhanced nonlinear absorption compared to bismuth telluride. Inset: TEM micrograph of bismuth telluride nanocrystallites. Highlights: Black-Right-Pointing-Pointer Synthesis of Nanocrystalline Bi{sub 2}Te{sub 3} and Thallium doped Bi{sub 2}Te{sub 3} through solvothermal method. Black-Right-Pointing-Pointer Reduced absorption coefficient due to thallium doping found from IR spectroscopy. Black-Right-Pointing-Pointer Open-aperture Z-scan technique for nonlinear optical studies. Black-Right-Pointing-Pointer Two photon absorption based model for theoretical fitting of Z-scan data. Black-Right-Pointing-Pointer Enhanced nonlinear absorption in Thallium doped Bi{sub 2}Te{sub 3} - potential candidate for optical power limiting applications.

Molli, Muralikrishna, E-mail: muralikrishnamolli@sssihl.edu.in [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India); Parola, Sowmendran; Avinash Chunduri, L.A.; Aditha, Saikiran; Sai Muthukumar, V; Mimani Rattan, Tanu; Kamisetti, Venkataramaniah [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India)

2012-05-15T23:59:59.000Z

378

Optical dichroism in nanotubes  

Science Journals Connector (OSTI)

Utilizing the line-group symmetry of single-wall nanotubes, we have assigned their electron-energy bands by symmetry-based quantum numbers. The selection rules for optical absorption are presented in terms of these quantum numbers. Different interband transitions become allowed as the polarization of incident light is varied, and we predict a substantial optical dichroism. We suggest how to observe this effect in experiments on a single nanotube, and how it can be used to control quantum transport in nanotubes to obtain information about the structure.

I. Božovi?; N. Božovi?; M. Damnjanovi?

2000-09-15T23:59:59.000Z

379

Full spectrum optical safeguard  

DOE Patents [OSTI]

An optical safeguard device with two linear variable Fabry-Perot filters aligned relative to a light source with at least one of the filters having a nonlinear dielectric constant material such that, when a light source produces a sufficiently high intensity light, the light alters the characteristics of the nonlinear dielectric constant material to reduce the intensity of light impacting a connected optical sensor. The device can be incorporated into an imaging system on a moving platform, such as an aircraft or satellite.

Ackerman, Mark R. (Albuquerque, NM)

2008-12-02T23:59:59.000Z

380

High-index-contrast electromechanical optical switches  

E-Print Network [OSTI]

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 ...

Bryant, Reginald (Reginald Eugene), 1978-

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

2.71 Optics, Fall 2001  

E-Print Network [OSTI]

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, ...

Barbastathis, George

382

Multi-Scale Optical Coherence Tomography Imaging  

E-Print Network [OSTI]

Fourier domain optical coherence tomography and methods forspeed spectral-domain optical coherence tomography at 1.3umJ. G. (1991). Optical coherence tomography. Science, 254(

Oliveira, Michael

2014-01-01T23:59:59.000Z

383

Advanced Photon Source | Combining Scanning Probe Microscopy and  

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

01.2013 01.2013 Nanoscience Seminar presented at Tokyo University On November 1, 2013, Volker Rose was invited to present the Nanoscience Seminar at the Institute of Solid State Physics (ISSP) of the University of Tokyo. In his seminar he discussed the physical principles of Synchrotron X-ray Scanning Tunneling Microscopy (SXSTM) as well as the recent progress made by his team at the Advanced Photon Source. He was invited by Prof. Yukio Hasegawa, who himself conducts SXSTM experiment at the Photon Factory in Tsukuba, Japan. The ISSP serves as the central laboratory of materials science in Japan equipped with state-of-art facilities. It was relocated to the new campus in Kashiwa of the University of Tokyo in 2000 after the 43 years of activities at the Roppongi campus in downtown Tokyo. Here ISSP is focusing

384

Advanced Photon Source | Combining Scanning Probe Microscopy and  

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

27.2013 27.2013 Researchers from NSLS-II visit SXSPM team at Argonne Synchrotron x-ray scanning tunneling microscopy will soon also be developed at the National Synchrotron Light Source (NSLS-II) at Brookhaven National Laboratory (BNL). In order to establish collaboration between the two National Laboratories, Drs. Evgeny Nazaretski and Hui Yan fom BNL visited Argonne to learn more about recent progress made in the SXSPM project. During the 2-day visit the teams discussed mutual scientific goals and strategies to achieve them. NSLS-II will be a new state-of-the-art, medium-energy electron storage ring at BNL designed to deliver high intensity and brightness. Construction of the NSLS-II's ring building began in March 2009. The new facility will begin operating in 2014

385

Advanced Photon Source | Combining Scanning Probe Microscopy and  

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

APS APS SXSPM News Researchers from NSLS-II visit SXSPM team at Argonne (November 27, 2013) Cummings presents invited talk at magnetism meeting (November 11, 2013) Invited talk at ACSIN-12 & ICSPM21 in Japan (November 11, 2013) Nanoscience Seminar presented at Tokyo University (November 01, 2013) Scientists study old photos for new solutions to corrosion (October 21, 2013) More News Featured Image Recent Publications Kangkang Wang, Daniel Rosenmann, Martin Holt, Robert Winarski, Saw-Wai Hla, and Volker Rose, "An easy-to-implement filter for separating photo-excited signals from topography in scanning tunneling microscopy", Rev. Sci. Instrum. 84, 063704 (2013). More SXSPM Publications Upcoming Presentations V. Rose, 41st Conference on the Physics and Chemistry of Surfaces and Interfaces (PCSI-41) (Invited Speaker)

386

The early history of the scanning electron microscope  

Science Journals Connector (OSTI)

The article begins with an account of prewar German work particularly that of von Ardenne who established the theoretical basis of a scanning electron microscope and constructed an instrument which was primarily intended to overcome chromatic aberration when relatively thick specimens were examined by transmission. Neither this microscope nor a different one built a few years later in the U. S. A. attained sufficient resolution to gain acceptance and the reasons for this are examined. The remainder of the article deals with work carried out in the Cambridge University Engineering Department over the years from 1948 to about 1965 when the first successful commercial instrument was produced. The contributions made by successive research students are explained as are also the nonscientific factors which influenced the course of the development.

C. W. Oatley

1982-01-01T23:59:59.000Z

387

Scanning Hall probe microscopy of a diluted magnetic semiconductor  

SciTech Connect (OSTI)

We have measured the micromagnetic properties of a diluted magnetic semiconductor as a function of temperature and applied field with a scanning Hall probe microscope built in our laboratory. The design philosophy for this microscope and some details are described. The samples analyzed in this work are Ga{sub 0.94}Mn{sub 0.06}As films grown by molecular beam epitaxy. We find that the magnetic domains are 2-4 mum wide and fairly stable with temperature. Magnetic clusters are observed above T{sub C}, which we ascribe to MnAs defects too small and sparse to be detected by a superconducting quantum interference device magnetometer.

Kweon, Seongsoo [Materials Science and Engineering, University of Texas at Austin, Austin, Texas 78712 (United States); Samarth, Nitin [Physics Department, Penn State University, University Park, Pennsylvania 16802 (United States); Lozanne, Alex de [Materials Science and Engineering, University of Texas at Austin, Austin, Texas 78712 (United States); Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)

2009-05-01T23:59:59.000Z

388

Combined Scanning Transmission Electron Microscopy Tilt- and Focal Series  

SciTech Connect (OSTI)

In this study, a combined tilt- and focal series is proposed as a new recording scheme for high-angle annular dark-field scanning transmission electron microscopy (STEM) tomography. Three-dimensional (3D) data were acquired by mechanically tilting the specimen, and recording a through-focal series at each tilt direction. The sample was a whole-mount macrophage cell with embedded gold nanoparticles. The tilt focal algebraic reconstruction technique (TF-ART) is introduced as a new algorithm to reconstruct tomograms from such combined tilt- and focal series. The feasibility of TF-ART was demonstrated by 3D reconstruction of the experimental 3D data. The results were compared with a conventional STEM tilt series of a similar sample. The combined tilt- and focal series led to smaller missing wedge artifacts, and a higher axial resolution than obtained for the STEM tilt series, thus improving on one of the main issues of tilt series-based electron tomography.

Dahmen, Tim [German Research Center for Artificial Intelligence (DFKI), Germany] [German Research Center for Artificial Intelligence (DFKI), Germany; Baudoin, Jean-Pierre G [ORNL] [ORNL; Lupini, Andrew R [ORNL] [ORNL; Kubel, Christian [Karlsruhe Institute of Technology, Leopoldshafen, Germany] [Karlsruhe Institute of Technology, Leopoldshafen, Germany; Slusallek, Phillip [German Research Center for Artificial Intelligence (DFKI), Germany] [German Research Center for Artificial Intelligence (DFKI), Germany; De Jonge, Niels [ORNL] [ORNL

2014-01-01T23:59:59.000Z

389

Optical technologies for the observation of low Earth orbit objects  

E-Print Network [OSTI]

In order to avoid collisions with space debris, the near Earth orbit must be continuously scanned by either ground- or spaced-based facilities. For the low Earth orbit, radar telescopes are the workhorse for this task, especially due to their continuous availability. However, optical observation methods can deliver complementary information, especially towards high accuracy measurements. Passive-optical observations are inexpensive and can yield very precise information about the apparent position of the object in the sky via comparison with background stars. However, the object's distance from the observer is not readily accessible, which constitutes a major drawback of this approach for the precise calculation of the orbital elements. Two experimental methods have been devised to overcome this problem: Using two observatories a few kilometres apart, strictly simultaneous observations of the same object yield an accurate, instantaneous 3D position determination through measurement of the parallax. If only on...

Hampf, Daniel; Riede, Wolfgang

2015-01-01T23:59:59.000Z

390

Development and comparison of algorithms for generating a scan sequence for a random access scanner. [ZAP (and flow charts for ZIP and SCAN), in FORTRAN for DEC-10  

SciTech Connect (OSTI)

Many data acquisition systems incorporate high-speed scanners to convert analog signals into digital format for further processing. Some systems multiplex many channels into a single scanner. A random access scanner whose scan sequence is specified by a table in random access memory will permit different scan rates on different channels. Generation of this scan table can be a tedious manual task when there are many channels (e.g. 50), when there are more than a few scan rates (e.g. 5), and/or when the ratio of the highest scan rate to the lowest scan rate becomes large (e.g. 100:1). An algorithm is developed which will generate these scan sequences for the random access scanner and implements the algorithm on a digital computer. Application of number theory to the mathematical statement of the problem led to development of several algorithms which were implemented in FORTRAN. The most efficient of these algorithms operates by partitioning the problem into a set of subproblems. Through recursion they solve each subproblem by partitioning it repeatedly into even smaller parts, continuing until a set of simple problems is created. From this process, a pictorial representation or wheel diagram of the problem can be constructed. From the wheel diagram and a description of the original problem, a scan table can be constructed. In addition, the wheel diagram can be used as a method of storing the scan sequence in a smaller amount of memory. The most efficient partitioning algorithm solved most scan table problems in less than a second of CPU time. Some types of problems, however, required as much as a few minutes of CPU time. 26 figures, 2 tables.

Eason, R. O.

1980-09-01T23:59:59.000Z

391

Integrated optics and new wave phenomena in optical waveguides  

Science Journals Connector (OSTI)

Research in integrated optics has two goals: One is to apply thin-film technology to the formation of optical devices and circuits. The other is the integration of a large number of optical devices on a small substrate, so forming an optical circuit reminiscent of the integrated circuit in microelectronics. The result is a new breed of optical devices in the form of miniature optical waveguides. They include lasers, modulators, switches, detectors, prisms, lenses, and polarizers, and many of them have efficiencies better than their bulk counterparts. Simple integrated optical circuits have also been constructed, and rapidly advancing semiconductor technology indicates that monolithic integrated optical circuits can readily be developed using GaAs-related compounds. In this paper, we review the state-of-the-art of integrated optics and explore new wave phenomena in optical circuits. The specific topics to be discussed are: light-wave couplers and m-line spectroscopy, refraction and reflection of light in thin films, normal modes of the uniform, the graded and the metal-clad waveguides, optics in tapered films, theory of corrugated waveguides, and more importantly, physics of various thin-film optical devices and the method of the circuit formation.

P. K. Tien

1977-04-01T23:59:59.000Z

392

Bachelor of Science Degree in Optics Bachelor of Science Degree in Optical Engineering  

E-Print Network [OSTI]

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

393

Bachelor of Science Degree in Optics Bachelor of Science Degree in Optical Engineering  

E-Print Network [OSTI]

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

Mahon, Bradford Z.

394

Split image optical display  

DOE Patents [OSTI]

A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

Veligdan, James T. (Manorville, NY)

2007-05-29T23:59:59.000Z

395

Quantum Optics (Nir Davidson -  

E-Print Network [OSTI]

Capacity and Cost Effectiveness Enhancment Technique Using a Combined Time Division and Multilevel California, USA, "Advanced System Functions in Optical Communications Using E-O Technologies" Moshe Nazarathy for fabricating printed circuit boards" Solar Cells (Jeffrey Gordon, Uzi Efron - Ben- Gurion University) David

Ribak, Erez

396

Glass for Optical Purposes  

Science Journals Connector (OSTI)

... THE importance of an adequate supply of optical glass of all the principal types cannot be overestimated. The improvement of the microscope has ... improvement of the microscope has been and is still retarded for the want of suitable glasses, the construction of large telescopes is limited by the capacity of the glassmaker to ...

S. D. CHALMERS

1914-10-01T23:59:59.000Z

397

Optical pumping of ions  

Science Journals Connector (OSTI)

Radiofrequency spectroscopy has been extended to positive ions with S ground states by means of optical pumping. The ions are stored in buffer gases or ion traps and are polarized directly by optical pumping or indirectly by spin exchange, change exchange, or Penning ionization with optically pumped atoms. The applied methods are described. The experiments can be divided into two categories: Collisional interactions of the polarized ions are investigated, like the exchange processes mentioned above, spin exchange with free electrons, spin depolarization and hyperfine density shifts in rare gases. For the two latter effects drastic differences are observed between atomic and ionic 2S12 states the explanations of which reveal the influence of the ionic charge on the interactions. The comparison of equivalent processes involving isoelectronic 2S or 2P configurations of atoms and ions provides a test of current collision theories. Precision rf spectroscopy of ionic ground states yields the 2S12 hyperfine structure splittings of 3He+ and group II ions with relative accuracies of up to 10?9, with further improvement possible. Direct and indirect optical pumping of 1S0 ions is used to determine nuclear magnetic moments, diamagnetic shielding coefficients, and chemical shifts. Applications and further developments of the present methods are discussed.

E.W. Weber

1977-01-01T23:59:59.000Z

398

Optical imaging of Rydberg atoms  

E-Print Network [OSTI]

We present an experiment exploring electromagnetically induced transparency (EIT) in Rydberg atoms in order to observe optical nonlinearities at the single photon level. ??Rb atoms are trapped and cooled using a magneto-optical ...

Mazurenko, Anton

2012-01-01T23:59:59.000Z

399

Miniature MT optical assembly (MMTOA)  

DOE Patents [OSTI]

An optical assembly (10) includes a rigid mount (12) with a recess (26) proximate a first side thereof, a substrate (14), and an optical die (16) flip-chip bonded to the substrate (14). The substrate (14) is secured to the first side of the mount and includes a plurality of die bonding elements (40), a plurality of optical apertures (32), and a plurality of external bonding elements (42). A plurality of traces (44) interconnect the die bonding elements (40) and the external bonding elements (42). The optical die (16) includes a plurality of optical elements, each element including an optical signal interface (48), the die being bonded to the plurality of die bonding elements (40) such that the optical signal interface (48) of each element is in registry with an optical aperture (32) of the substrate (14) and the die (16) is at least partially enclosed by the recess (26).

Laughlin, Daric (Overland Park, KS); Abel, Phillip (Overland Park, KS)

2008-04-01T23:59:59.000Z

400

Science, Optics and You Guidebook  

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

- 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-based interdisciplinary...

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Science, Optics and You: Introduction  

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

- 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-based interdisciplinary...

402

Crooker named Optical Society Fellow  

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

Crooker named Optical Society Fellow January 23, 2014 Scott Crooker of LANL's Condensed Matter and Magnet Science group is a 2014 Fellow of the Optical Society (OSA). The Society...

403

Differential displacement measurement using scanning x-ray beams  

Science Journals Connector (OSTI)

A noncontacting method for measuring mechanical strain between two fiducial marks has been developed for use where environmental conditions would be disruptive to methods utilizing optical light. A silicon 111 Johansson crystal is used for this application where Mo K? radiation is used to fluoresce fiducial markers made of yittria-stabilized zirconia. This substance is used for a thermal barrier coating in gas turbine engines and the technology for applying this material to withstand long term high temperature exposure is highly developed. The current system has a displacement repeatability of better than 0.1 ?m which is not limited by counting statistics but rather determined by mechanical considerations.

Howard A. Canistraro; Eric H. Jordan; Douglas M. Pease

1998-01-01T23:59:59.000Z

404

Large core fiber optic cleaver  

DOE Patents [OSTI]

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.

Halpin, J.M.

1996-03-26T23:59:59.000Z

405

Optical computing Damien Woods a  

E-Print Network [OSTI]

Optical computing Damien Woods a aDepartment of Computer Science and Artificial Intelligence Institute, Vierimaantie 5, 84100 Ylivieska, Finland Abstract We consider optical computers that encode data using images and compute by transforming such images. We give an overview of a number of such optical

Woods, Damien

406

Nonlinear optics at maximum coherence  

Science Journals Connector (OSTI)

...D. Walls Nonlinear optics at maximum coherence S. E. Harris G. Y. Yin M. Jain H...optical processes which utilize maximum coherence of a non-allowed transition. The nonlinear...frequency. Nonlinear optics at maximum coherence B y S. E. Harris, G. Y. Yin, M...

1997-01-01T23:59:59.000Z

407

Aerogel-clad optical fiber  

DOE Patents [OSTI]

An optical fiber is surrounded by an aerogel cladding. For a low density aerogel, the index of refraction of the aerogel is close to that of air, which provides a high numerical aperture to the optical fiber. Due to the high numerical aperture, the aerogel clad optical fiber has improved light collection efficiency.

Sprehn, Gregory A. (Livermore, CA); Hrubesh, Lawrence W. (Pleasanton, CA); Poco, John F. (Livermore, CA); Sandler, Pamela H. (San Marino, CA)

1997-01-01T23:59:59.000Z

408

A laser scanning system for metrology and viewing in ITER  

SciTech Connect (OSTI)

The construction and operation of a next-generation fusion reactor will require metrology to achieve and verify precise alignment of plasma-facing components and inspection in the reactor vessel. The system must be compatible with the vessel environment of high gamma radiation (10{sup 4} Gy/h), ultra-high-vacuum (10{sup {minus}8} torr), and elevated temperature (200 C). The high radiation requires that the system be remotely deployed. A coherent frequency modulated laser radar-based system will be integrated with a remotely operated deployment mechanism to meet these requirements. The metrology/viewing system consists of a compact laser transceiver optics module which is linked through fiber optics to the laser source and imaging units that are located outside of a biological shield. The deployment mechanism will be a mast-like positioning system. Radiation-damage tests will be conducted on critical sensor components at Oak Ridge National Laboratory to determine threshold damage levels and effects on data transmission. This paper identifies the requirements for International Thermonuclear Experimental Reactor metrology and viewing and describes a remotely operated precision ranging and surface mapping system.

Spampinato, P.T.; Barry, R.E.; Menon, M.M.; Herndon, J.N. [Oak Ridge National Lab., TN (United States); Dagher, M.A.; Maslakowski, J.E. [Rockwell Rocketdyne Div., Canoga Park, CA (United States)

1996-05-01T23:59:59.000Z

409

Optical Tweezer Arrays and Optical Substrates Created with Diffractive Optics Eric R. Dufresne and David G. Grier  

E-Print Network [OSTI]

Optical Tweezer Arrays and Optical Substrates Created with Diffractive Optics Eric R. Dufresne optical tweezers from a single laser beam using diffractive optical elements. As a demonstration of this technique, we have implemented a 4 \\Theta 4 square array of optical tweezers -- the hexadeca

Grier, David

410

Optical characterization of damage resistant kilolayer'' rugate filters  

SciTech Connect (OSTI)

Multilayer dielectric optical coatings produced by high temperature plasma-assisted chemical vapor deposition (PCVD) have been previously shown to have very high surface and bulk damage thresholds (above 40J/cm{sup 2}). Because these experimental coatings are deposited on tubular substrates, conventional wavelength scanning cannot accurately measure the coating peak reflectance and bandwidth. Measurement of the variation of transmittance with incidence angle at fixed wavelength permits analysis of the coating spectral response. The results indicate that the PCVD coatings behave as nearly ideal'' rugate filters. Their optical performance agrees well with that predicted for a rugate by Southwell's coupled-wave theory and by the characteristic-matrix model. These 1000-layer-pair filters have maximum reflectances exceeding 99.9%, peak reflectance wavelengths within 0.5% of the design wavelength, and FWHM bandwidths narrower than 10 nm. Minor perturbations to the ideal rugate sinusoidal profile do not appreciably affect the coating optical performance. Comparison with calculations suggest that the only significant deviation of the PCVD structure from that of an ideal rugate is a small (0.7%) drift in the index period. Excellent optical performance and high damage resistance makes PCVD rugate coatings potentially useful for several high power laser applications. 13 refs., 7 figs.

Elder, M.L.; Jancaitis, K.S.; Milam, D.; Campbell, J.H.

1990-12-17T23:59:59.000Z

411

Bonded, walk-off compensated optical elements  

DOE Patents [OSTI]

A bonded, walk-off compensated crystal, for use with optical equipment, and methods of making optical components including same.

Ebbers, Christopher A. (Livermore, CA)

2003-04-08T23:59:59.000Z

412

A Mobile Automated Tomographic Gamma Scanning System - 13231  

SciTech Connect (OSTI)

Canberra Industries have recently designed and built a new automated Tomographic Gamma Scanning (TGS) system for mobile deployment. The TGS technique combines high-resolution gamma spectroscopy with low spatial resolution 3-dimensional image reconstruction to provide increased accuracy over traditional approaches for the assay of non-uniform source distributions in low-to medium-density, non-heterogeneous matrices. Originally pioneered by R. Estep at Los Alamos National Laboratory (LANL), the TGS method has been further developed and commercialized by Canberra Industries in recent years. The present system advances the state of the art on several fronts: it is designed to be housed in a standard cargo transport container for ease of transport, allowing waste characterization at multiple facilities under the purview of a single operator. Conveyor feed, drum rotator, and detector and collimator positioning mechanisms operated by programmable logic control (PLC) allow automated batch mode operation. The variable geometry settings can accommodate a wide range of waste packaging, including but not limited to standard 220 liter drums, 380 liter overpack drums, and smaller 20 liter cans. A 20 mCi Eu-152 transmission source provides attenuation corrections for drum matrices up to 1 g/cm{sup 3} in TGS mode; the system can be operated in Segmented Gamma Scanning (SGS) mode to measure higher density drums. To support TGS assays at higher densities, the source shield is sufficient to house an alternate Co-60 transmission source of higher activity, up to 250 mCi. An automated shutter and attenuator assembly is provided for operating the system with a dual intensity transmission source. The system's 1500 kg capacity rotator turntable can handle heavy containers such as concrete lined 380 liter overpack drums. Finally, data acquisition utilizes Canberra's Broad Energy Germanium (BEGE) detector and Lynx MCA, with 32 k channels, providing better than 0.1 keV/channel resolution to support both isotopic analysis with the MGA/MGAU software and a wide 3 MeV dynamic range. The calibration and verification of the system is discussed, and quantitative results are presented for a variety of drum types and matrices. (authors)

Kirkpatrick, J.M.; LeBlanc, P.J.; Nakazawa, D.; Petroka, D.L.; Kane Smith, S.; Venkataraman, R.; Villani, M. [Canberra Industries, Inc. 800 Research Parkway, Meriden CT 06450 (United States)] [Canberra Industries, Inc. 800 Research Parkway, Meriden CT 06450 (United States)

2013-07-01T23:59:59.000Z

413

Large optics inspection, tilting, and washing stand  

DOE Patents [OSTI]

A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

Ayers, Marion Jay (Brentwood, CA); Ayers, Shannon Lee (Brentwood, CA)

2010-08-24T23:59:59.000Z

414

Low-Dose Spiral CT Scans for Early Lung Cancer Detection | Department of  

Broader source: Energy.gov (indexed) [DOE]

Low-Dose Spiral CT Scans for Early Lung Cancer Detection Low-Dose Spiral CT Scans for Early Lung Cancer Detection Low-Dose Spiral CT Scans for Early Lung Cancer Detection Low-dose spiral computed tomography (CT) scanning is a noninvasive medical imaging test that has been used for the early detection of lung cancer for over 16 years (Sone et al. 1998; Henschke et.al. 1999). A low-dose spiral chest CT differs from a full-dose conventional chest CT scan primarily in the amount of radiation emitted during CT scans. Chest CT, in general, requires less radiation exposure than other CT procedures because the air-filled tissues of the lungs are not as dense as the tissues of other organs (i.e., less x-ray radiation is needed to penetrate the lung). Radiation dose can be further reduced with lung cancer screening due to the

415

Optical Network Testbeds Workshop  

SciTech Connect (OSTI)

This is the summary report of the third annual Optical Networking Testbed Workshop (ONT3), which brought together leading members of the international advanced research community to address major challenges in creating next generation communication services and technologies. Networking research and development (R&D) communities throughout the world continue to discover new methods and technologies that are enabling breakthroughs in advanced communications. These discoveries are keystones for building the foundation of the future economy, which requires the sophisticated management of extremely large qualities of digital information through high performance communications. This innovation is made possible by basic research and experiments within laboratories and on specialized testbeds. Initial network research and development initiatives are driven by diverse motives, including attempts to solve existing complex problems, the desire to create powerful new technologies that do not exist using traditional methods, and the need to create tools to address specific challenges, including those mandated by large scale science or government agency mission agendas. Many new discoveries related to communications technologies transition to wide-spread deployment through standards organizations and commercialization. These transition paths allow for new communications capabilities that drive many sectors of the digital economy. In the last few years, networking R&D has increasingly focused on advancing multiple new capabilities enabled by next generation optical networking. Both US Federal networking R&D and other national R&D initiatives, such as those organized by the National Institute of Information and Communications Technology (NICT) of Japan are creating optical networking technologies that allow for new, powerful communication services. Among the most promising services are those based on new types of multi-service or hybrid networks, which use new optical networking technologies. Several years ago, when many of these optical networking research topics were first being investigated, they were the subject of controversial debate. The new techniques challenged many long-held concepts related to architecture and technology. However, today all major networking organizations are transitioning toward infrastructure that incorporates these new concepts. This progress has been assisted through the series of Optical Networking Testbed Workshops (ONT). The first (ONT1) outlined a general framework of key issues and topics and developed a series of recommendations (www.nren.nasa.gov/workshop7). The second (ONT2) developed a common vision of optical network technologies, services, infrastructure, and organizations (www.nren.nasa.gov/workshop8). Processes that allow for a common vision encourage widespread deployment of these types of resources among advanced networking communities. Also, such a shared vision enables key concepts and technologies to migrate from basic research testbeds to wider networking communities. The ONT-3 workshop built on these earlier activities by expanding discussion to include additional considerations of the international interoperability and of greater impact of optical networking technology on networking in general. In accordance with this recognition, the workshop confirmed that future-oriented research and development is indispensable to fundamentally change the current Internet architecture to create a global network incorporating completely new concepts. The workshop also recognized that the first priority to allow for this progress is basic research and development, including international collaborative activities, which are important for the global realization of interoperability of a new generation architecture.

Joe Mambretti

2007-06-01T23:59:59.000Z

416

Modular optical detector system  

DOE Patents [OSTI]

A modular optical detector system. The detector system is designed to detect the presence of molecules or molecular species by inducing fluorescence with exciting radiation and detecting the emitted fluorescence. Because the system is capable of accurately detecting and measuring picomolar concentrations it is ideally suited for use with microchemical analysis systems generally and capillary chromatographic systems in particular. By employing a modular design, the detector system provides both the ability to replace various elements of the detector system without requiring extensive realignment or recalibration of the components as well as minimal user interaction with the system. In addition, the modular concept provides for the use and addition of a wide variety of components, including optical elements (lenses and filters), light sources, and detection means, to fit particular needs.

Horn, Brent A. (Livermore, CA); Renzi, Ronald F. (Tracy, CA)

2006-02-14T23:59:59.000Z

417

LSST Camera Optics  

SciTech Connect (OSTI)

The Large Synoptic Survey Telescope (LSST) is a unique, three-mirror, modified Paul-Baker design with an 8.4m primary, a 3.4m secondary, and a 5.0m tertiary feeding a camera system that includes corrector optics to produce a 3.5 degree field of view with excellent image quality (<0.3 arcsecond 80% encircled diffracted energy) over the entire field from blue to near infra-red wavelengths. We describe the design of the LSST camera optics, consisting of three refractive lenses with diameters of 1.6m, 1.0m and 0.7m, along with a set of interchangeable, broad-band, interference filters with diameters of 0.75m. We also describe current plans for fabricating, coating, mounting and testing these lenses and filters.

Olivier, S S; Seppala, L; Gilmore, K; Hale, L; Whistler, W

2006-06-05T23:59:59.000Z

418

Fiber optic moisture sensor  

DOE Patents [OSTI]

A method and apparatus for sensing moisture changes by utilizing optical fiber technology. One embodiment uses a reflective target at the end of an optical fiber. The reflectance of the target varies with its moisture content and can be detected by a remote unit at the opposite end of the fiber. A second embodiment utilizes changes in light loss along the fiber length. This can be attributed to changes in reflectance of cladding material as a function of its moisture content. It can also be affected by holes or inserts interposed in the cladding material and/or fiber. Changing light levels can also be coupled from one fiber to another in an assembly of fibers as a function of varying moisture content in their overlapping lengths of cladding material.

Kirkham, R.R.

1984-08-03T23:59:59.000Z

419

Existence of Optical Vortices  

E-Print Network [OSTI]

Optical vortices arise as phase singularities of the light fields and are of central interest in modern optical physics. In this paper, some existence theorems are established for stationary vortex wave solutions of a general class of nonlinear Schr\\"{o}dinger equations. There are two types of results. The first type concerns the existence of positive-radial-profile solutions which are obtained through a constrained minimization approach. The second type addresses the existence of saddle-point solutions through a mountain-pass-theorem or min-max method so that the wave propagation constant may be arbitrarily prescribed in an open interval. Furthermore some explicit estimates for the lower bound and sign of the wave propagation constant with respect to the light beam power and vortex winding number are also derived for the first type solutions.

Yisong Yang; Ruifeng Zhang

2012-09-21T23:59:59.000Z

420

MicroSight Optics  

SciTech Connect (OSTI)

MicroSight is an innovative gunsight technology that allows a marksman's eye to focus on both the front gunsight and the intended target. The MicroSight improves both firearm safety and performance by imaging two objects at different focal distances. The MicroSight was developed at Idaho National Laboratory, and has been licensed by Apollo Optical Systems. You can learn more about INL's research programs at http://www.facebook.com/idahonationallaboratory.

None

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Optically pulsed electron accelerator  

DOE Patents [OSTI]

An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

Fraser, J.S.; Sheffield, R.L.

1985-05-20T23:59:59.000Z

422

Fourier optics on graphene  

Science Journals Connector (OSTI)

Using numerical simulations, here, we demonstrate that a single sheet of graphene with properly designed inhomogeneous, nonuniform conductivity distributions can act as a convex lens for focusing and collimating the transverse-magnetic (TM) surface plasmon polariton (SPP) surface waves propagating along the graphene. Consequently, we show that the graphene can act as a platform for obtaining spatial Fourier transform of infrared (IR) SPP signals. This may lead to rebirth of the field of Fourier optics on a 1-atom-thick structure.

Ashkan Vakil and Nader Engheta

2012-02-27T23:59:59.000Z

423

Optically Controlled Jitter Generator  

E-Print Network [OSTI]

A new simple circuit producing random pulse trains is proposed and experimentally studied. The circuit is composed of an operational amplifier and two feedback links, one of which comprises two photodiodes. The photodiodes are responsible for nonlinearity in the feedback. By varying the illumination it is possible to control the nonlinearity in the photodiode current-voltage characteristics and change the degree of randomness in the oscillations. The circuit's simplicity and optical control make it attractive for coupled map lattices.

Julia Manasson; V. A. Manasson

2006-08-17T23:59:59.000Z

424

Fiber optic geophysical sensors  

DOE Patents [OSTI]

A fiber optic geophysical sensor in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects.

Homuth, Emil F. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

425

Optically pulsed electron accelerator  

DOE Patents [OSTI]

An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

Fraser, John S. (Los Alamos, NM); Sheffield, Richard L. (Los Alamos, NM)

1987-01-01T23:59:59.000Z

426

MicroSight Optics  

ScienceCinema (OSTI)

MicroSight is an innovative gunsight technology that allows a marksman's eye to focus on both the front gunsight and the intended target. The MicroSight improves both firearm safety and performance by imaging two objects at different focal distances. The MicroSight was developed at Idaho National Laboratory, and has been licensed by Apollo Optical Systems. You can learn more about INL's research programs at http://www.facebook.com/idahonationallaboratory.

None

2013-05-28T23:59:59.000Z

427

Third order nonlinear optical properties of bismuth zinc borate glasses  

SciTech Connect (OSTI)

Third order nonlinear optical characterization of bismuth zinc borate glasses are reported here using different laser pulse durations. Bismuth zinc borate glasses with compositions xBi{sub 2}O{sub 3}-30ZnO-(70-x) B{sub 2}O{sub 3} (where x?=?30, 35, 40, and 45?mol. %) have been prepared by melt quenching method. These glasses were characterized by Raman, UV-Vis absorption, and Z scan measurements. Raman and UV-Vis spectroscopic results indicate that non-bridging oxygens increase with increase of bismuth content in the glass. Nonlinear absorption and refraction behavior in the nanosecond (ns), picosecond (ps), and femtosecond (fs) time domains were studied in detail. Strong reverse saturable absorption due to dominant two-photon absorption (TPA) was observed with both ps and fs excitations. In the case of ns pulse excitations, TPA and free-carrier absorption processes contribute for the nonlinear absorption. Two-photon absorption coefficient (?) and the absorption cross section due to free carriers (?{sub e}) are estimated by theoretical fit of the open aperture Z-scan measurements and found to be dependent on the amount of bismuth oxide in the glass composition. In both ns and fs regimes the sign and magnitude of the third order nonlinearity are evaluated, and the optical limiting characteristics are also reported.

Shanmugavelu, B.; Ravi Kanth Kumar, V. V., E-mail: ravi.phy@pondiuni.edu.in [Department of Physics, Pondicherry University, Puducherry 605 014 (India); Kuladeep, R.; Narayana Rao, D. [School of Physics, University of Hyderabad, Hyderabad 500046, Andhra Pradesh (India)

2013-12-28T23:59:59.000Z

428

Band excitation method applicable to scanning probe microscopy  

DOE Patents [OSTI]

Methods and apparatus are described for scanning probe microscopy. A method includes generating a band excitation (BE) signal having finite and predefined amplitude and phase spectrum in at least a first predefined frequency band; exciting a probe using the band excitation signal; obtaining data by measuring a response of the probe in at least a second predefined frequency band; and extracting at least one relevant dynamic parameter of the response of the probe in a predefined range including analyzing the obtained data. The BE signal can be synthesized prior to imaging (static band excitation), or adjusted at each pixel or spectroscopy step to accommodate changes in sample properties (adaptive band excitation). An apparatus includes a band excitation signal generator; a probe coupled to the band excitation signal generator; a detector coupled to the probe; and a relevant dynamic parameter extractor component coupled to the detector, the relevant dynamic parameter extractor including a processor that performs a mathematical transform selected from the group consisting of an integral transform and a discrete transform.

Jesse, Stephen; Kalinin, Sergei V

2013-05-28T23:59:59.000Z

429

Laboratory evaluation of the IriScan prototype biometric identifier  

SciTech Connect (OSTI)

One thing that all access control applications have in common is the need to identify those individuals authorized to gain access to an area. Traditionally, the identification is based on something that person possesses, such as a key or badge, or something they know, such as a PIN or password. Biometric identifiers make their decisions based on the physiological or behavioral characteristics of individuals. The potential of biometrics devices to positively identify individuals has made them attractive for use in access control and computer security applications. However, no systems perform perfectly, so it is important to understand what a biometric device`s performance is under real world conditions before deciding to implement one in an access control system. This paper will describe the evaluation of a prototype biometric identifier provided by IriScan Incorporated. This identifier was developed to recognize individual human beings based on the distinctive visual characteristics of the irises of their eyes. The main goal of the evaluation was to determine whether the system has potential as an access control device within the Department of Energy (DOE). The primary interest was an estimate of the accuracy of the system in terms of false accept and false reject rates. Data was also collected to estimate throughput time and user acceptability. The performance of the system during the test will be discussed. Lessons learned during the test which may aid in further testing and simplify implementation of a production system will also be discussed.

Bouchier, F.; Ahrens, J.S.; Wells, G.

1996-04-01T23:59:59.000Z

430

Solar collector systems analysis using infrared scanning techniques  

SciTech Connect (OSTI)

Solar energy collector systems analysis using thermography is discussed. The research at the Solar Energy Research Institute (SERI) in this area has focused on infrared (IR) scanning techniques and equipment to determine temperature distributions, flow patterns, and air blockages in solar collectors. The results of this extensive study, covering many sites and types of collectors, illustrate the capabilities of IR analysis as an analysis tool and operation and maintenance procedure when applied to large arrays. Infrared analysis of most collector systems showed temperature distributions that indicated balanced flow patterns with both the thermographs and the hand-held unit. In three significant cases, blocked or broken collector arrays, which previously had gone undetected, were discovered. Using this analysis, validation studies of large computer codes could examine collector arrays for flow patterns or blockages that could cause disagreement between actual and predicted performance. Initial operation and balancing of large systems could be accomplished without complicated sensor systems not needed for normal operations. Maintenance personnel could quickly check their systems without climbing onto the roof and without complicated sensor systems.

Eden, A.

1980-08-01T23:59:59.000Z

431

Microwave beam steerers for electronically scanned reflectometers (abstract)  

SciTech Connect (OSTI)

One of the problems encountered in the application of reflectometry to fusion plasmas is that the transmit antenna must be aligned such that the reflected wave form is successfully collected by a suitably arranged receive antenna. This task is made even more difficult in the case of shaped plasmas, or when plasma motion is such that the incident wave is no longer normal to the plasma surface. One would ideally like to have antennas which may be steered in real time to compensate for changes in plasma shape and/or position. A program has been initiated at U.C. Davis to address this problem, and microwave beam steerers suitable for electronically scanned reflectometers have been developed. The approach taken has been to develop phased antenna array (PAA) concepts which operate over broad bandwidths. Laboratory test results of a proof-of-principle PAA system will be presented, along with a description of ongoing research activities by U.C. Davis in this field. {copyright} {ital 1999 American Institute of Physics.}

Hsia, R.P.; Zhang, W.; Jiang, F.; Domier, C.W.; Luhmann, N.C. Jr. [University of California, Davis, Davis, California 95616 (United States)] [University of California, Davis, Davis, California 95616 (United States)

1999-01-01T23:59:59.000Z

432

Dual energy scanning beam laminographic x-radiography  

DOE Patents [OSTI]

A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images. By having multiple detectors located at different positions, a dual energy laminography system is possible.

Majewski, Stanislaw (Grafton, VA); Wojcik, Randolph F. (Yorktown, VA)

1998-01-01T23:59:59.000Z

433

Dual energy scanning beam laminographic x-radiography  

DOE Patents [OSTI]

A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images. By having multiple detectors located at different positions, a dual energy laminography system is possible. 6 figs.

Majewski, S.; Wojcik, R.F.

1998-04-21T23:59:59.000Z

434

Calibrated nanoscale dopant profiling using a scanning microwave microscope  

SciTech Connect (OSTI)

The scanning microwave microscope is used for calibrated capacitance spectroscopy and spatially resolved dopant profiling measurements. It consists of an atomic force microscope combined with a vector network analyzer operating between 1-20 GHz. On silicon semiconductor calibration samples with doping concentrations ranging from 10{sup 15} to 10{sup 20} atoms/cm{sup 3}, calibrated capacitance-voltage curves as well as derivative dC/dV curves were acquired. The change of the capacitance and the dC/dV signal is directly related to the dopant concentration allowing for quantitative dopant profiling. The method was tested on various samples with known dopant concentration and the resolution of dopant profiling determined to 20% while the absolute accuracy is within an order of magnitude. Using a modeling approach the dopant profiling calibration curves were analyzed with respect to varying tip diameter and oxide thickness allowing for improvements of the calibration accuracy. Bipolar samples were investigated and nano-scale defect structures and p-n junction interfaces imaged showing potential applications for the study of semiconductor device performance and failure analysis.

Huber, H. P.; Hochleitner, M.; Hinterdorfer, P. [University of Linz, Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Altenbergerstrasse 69, 4040 Linz (Austria); Humer, I.; Smoliner, J. [Technical University of Vienna, Institute for Solid State Electronics, 1040 Vienna (Austria); Fenner, M.; Moertelmaier, M.; Rankl, C.; Tanbakuchi, H.; Kienberger, F. [Agilent Technologies, Inc., 5301 Stevens Creek Blvd., Santa Clara, California 95051 (United States); Imtiaz, A.; Wallis, T. M.; Kabos, P. [National Institute for Standards and Technology, Electromagnetic Division, 325 Broadway, Boulder, Colorado 80305-3337 (United States); Kopanski, J. J. [National Institute of Standards and Technology, Semiconductor Measurements Division, Gaithersburg, Maryland 20899-8120 (United States)

2012-01-01T23:59:59.000Z

435

Optical fiber inspection system  

DOE Patents [OSTI]

A remote optical inspection system including an inspection head. The inspection head has a passageway through which pellets or other objects are passed. A window is provided along the passageway through which light is beamed against the objects being inspected. A plurality of lens assemblies are arranged about the window so that reflected light can be gathered and transferred to a plurality of coherent optical fiber light guides. The light guides transfer the light images to a television or other image transducer which converts the optical images into a representative electronic signal. The electronic signal can then be displayed on a signal viewer such as a television monitor for inspection by a person. A staging means can be used to support the objects for viewing through the window. Routing means can be used to direct inspected objects into appropriate exit passages for accepted or rejected objects. The inspected objects are advantageously fed in a singular manner to the staging means and routing means. The inspection system is advantageously used in an enclosure when toxic or hazardous materials are being inspected. 10 figs.

Moore, F.W.

1985-04-05T23:59:59.000Z

436

Virtual Optical Comparator  

SciTech Connect (OSTI)

The Virtual Optical Comparator, VOC, was conceived as a result of the limitations of conventional optical comparators and vision systems. Piece part designs for mechanisms have started to include precision features on the face of parts that must be viewed using a reflected image rather than a profile shadow. The VOC concept uses a computer generated overlay and a digital camera to measure features on a video screen. The advantage of this system is superior edge detection compared to traditional systems. No vinyl charts are procured or inspected. The part size and expensive fixtures are no longer a concern because of the range of the X-Y table of the Virtual Optical Comparator. Product redesigns require only changes to the CAD image overlays; new vinyl charts are not required. The inspection process is more ergonomic by allowing the operator to view the part sitting at a desk rather than standing over a 30 inch screen. The procurement cost for the VOC will be less than a traditional comparator with a much smaller footprint with less maintenance and energy requirements.

Thompson, Greg

2008-10-20T23:59:59.000Z

437

Optical ionization detector  

DOE Patents [OSTI]

An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium. 3 figures.

Wuest, C.R.; Lowry, M.E.

1994-03-29T23:59:59.000Z

438

Optical ionization detector  

DOE Patents [OSTI]

An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium.

Wuest, Craig R. (Danville, CA); Lowry, Mark E. (Castro Valley, CA)

1994-01-01T23:59:59.000Z

439

Device for translating negative film image to a line scan  

DOE Patents [OSTI]

A negative film reader records high-resolution optical density changes across negative film radiographic images to allow precise image dimensions to be determined. A laser light source capable of high-resolution focusing is passed through an intensity control filter, focused by a lens, and reflected off a mirror to focus in the plane of the negative film. The light transmitted through the film is collected by a second lens and directed to a photo diode detector which senses the transmitted intensity. The output of the photo diode signal amplifier is sent to the Y-axis input of an X-Y recorder. The film sample is transported in a plane perpendicular to the beam axis by means of a slide. The film position is monitored, with the signal amplified and recorded as the X-axis on the X-Y recorder. The linear dimensions and positions of image components can be determined by direct measurement of the amplified recording.

Dutton, G.W.

1998-05-19T23:59:59.000Z

440

Size dependent nonlinear optical properties of YCrO{sub 3} nanosystems  

SciTech Connect (OSTI)

We report size-dependent optical limiting response of YCrO{sub 3} nanosystems upon illumination by nanosecond laser pulses at 532 nm. The limiting properties were investigated using the open aperture z-scan technique. Three-photon absorption coefficient is found to increase with particle size within the range of our investigations. We propose that the obtained nonlinearity is caused by two photon absorption, followed by excited state absorption.

Krishnan, Shiji, E-mail: shijikrish@gmail.com [School of Pure and Applied Physics, Mahatma Gandhi University, Kottayam-686 560, Kerala (India); Shafakath, K.; Philip, Reji [Light and Matter Physics Group, Raman Research Institute, Bangalore- 560 080, Karnataka (India); Kalarikkal, Nandakumar, E-mail: nkkalarikkal@mgu.ac.in [School of Pure and Applied Physics, Mahatma Gandhi University, Kottayam-686 560, Kerala and Center for Nanoscience and Nanotechnology, Mahatma Gandhi University, Kottayam-686 560, Kerala (India)

2014-01-28T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

E-Print Network 3.0 - automatic scanning system Sample Search...  

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

Engineering 18 Performance Evaluation 63 (2006) 700723 On the performance of Internet worm scanning strategies Summary: address in a time interval , q Z(t) number of...

442

E-Print Network 3.0 - association scan reveals Sample Search...  

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

changed?" The remainder... into clusters, which are then grouped by target destination ports. This final comparison reveals scanning... are then grouped by target destination...

443

E-Print Network 3.0 - acoustic wave-assisted scanning Sample...  

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

Key words: frequency-dependent backscatter... sonographic scanning system are made from radio frequency (RF) echo signals. The RF echo signals are ... Source: Illinois at...

444

Electron and Scanning Probe Microscopies | U.S. DOE Office of Science (SC)  

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

Electron and Scanning Probe Microscopies Electron and Scanning Probe Microscopies Materials Sciences and Engineering (MSE) Division MSE Home About Research Areas Energy Frontier Research Centers (EFRCs) DOE Energy Innovation Hubs BES Funding Opportunities The Computational Materials and Chemical Sciences Network (CMCSN) Theoretical Condensed Matter Physics Scientific Highlights Reports and Activities Principal Investigators' Meetings BES Home Research Areas Electron and Scanning Probe Microscopies Print Text Size: A A A RSS Feeds FeedbackShare Page This research area supports basic research in condensed matter physics and materials physics using electron scattering and microscopy and scanning probe techniques. The research includes experiments and theory to understand the atomic, electronic, and magnetic structures of materials.

445

Optical Microscopy and 4Optical Microscopy and 4 Pi MicroscopyPi Microscopy  

E-Print Network [OSTI]

Optical Microscopy and 4Optical Microscopy and 4 Pi MicroscopyPi Microscopy Carolyn A. SuttonCarolyn A. Sutton PH 464PH 464 #12;OverviewOverview The OpticalThe Optical MicroscopeMicroscopy 4 Pi Microscopy4 Pi Microscopy Optical Microscope for Metallography #12;Optical Microscope: OriginsOptical

La Rosa, Andres H.

446

An optical fan for light beams for high-precision optical measurements and optical switching  

E-Print Network [OSTI]

The polarization and orbital angular momentum properties of light are of great importance in optical science and technology in the fields of high precision optical measurements and high capacity and high speed optical communications. Here we show, a totally new method, based on a combination of these two properties and using the thermal dispersion and electro-optical effect of birefringent crystals, the construction of a simple and robust scheme to rotate a light beam like a fan. Using a computer-based digital image processing technique, we determine the temperature and the thermal dispersion difference of the crystal with high resolution. We also use the rotation phenomenon to realize thermo-optic and electro-optic switches. The basic operating principles for measurement and switching processes are presented in detail. The methods developed here will have wide practical applicability in various fields, including remote sensing, materials science and optical communication networks.

Zhou, Zhi-Yuan; Ding, Dong-Sheng; Jiang, Yun-Kun; Zhang, Wei; Shi, Shuai; Shi, Bao-Sen; Guo, Guang-Can

2014-01-01T23:59:59.000Z

447

An optical fan for light beams for high-precision optical measurements and optical switching  

E-Print Network [OSTI]

The polarization and orbital angular momentum properties of light are of great importance in optical science and technology in the fields of high precision optical measurements and high capacity and high speed optical communications. Here we show, a totally new method, based on a combination of these two properties and using the thermal dispersion and electro-optical effect of birefringent crystals, the construction of a simple and robust scheme to rotate a light beam like a fan. Using a computer-based digital image processing technique, we determine the temperature and the thermal dispersion difference of the crystal with high resolution. We also use the rotation phenomenon to realize thermo-optic and electro-optic switches. The basic operating principles for measurement and switching processes are presented in detail. The methods developed here will have wide practical applicability in various fields, including remote sensing, materials science and optical communication networks.

Zhi-Yuan Zhou; Yan Li; Dong-Sheng Ding; Yun-Kun Jiang; Wei Zhang; Shuai Shi; Bao-Sen Shi; Guang-Can Guo

2014-05-08T23:59:59.000Z

448

Results of mobile gamma scanning activities in St. Louis, Missouri  

SciTech Connect (OSTI)

From 1942 through approximately 1966, the Mallinckrodt Chemical Works operated four plants in St. Louis, Missouri, for the Manhattan Engineer District and the Atomic Energy Commission. A variety of production processes using uranium- and radium-bearing ore materials were performed at the plants. It is the policy of the DOE to verify that radiological conditions at such sites or facilities comply with current DOE guidelines. Guidelines for release and use of such sites have become more stringent as research has provided more information since previous cleanups. The Formerly Utilized Sites Remedial Action Program (FUSRAP) was established as part of that effort to confirm the closeout status of facilities under contract to agencies preceding DOE during early nuclear energy development. Under the FUSRAP program, the Mallinckrodt properties have been previously investigated to determine the extent of on-site radiological contamination. At the request of DOE, Oak Ridge National Laboratory (ORNL) conducted a survey in May 1990, of public roadways and suspected haul routes between the Mallinckrodt plant and storage sites in St. Louis to ensure that no residual radioactive materials were conveyed off-site. A mobile gamma scanning van with an on-board computer system was used to identify possible anomalies. Suspect areas are those displaying measurements deviating from gamma exposure rates identified as typical for radiologically unenhanced areas in the vicinity of the areas of interest. The instrumentation highlighted three anomaly locations each of which measured less than 1m{sup 2} in size. None of the slightly elevated radiation levels originated from material associated with former AEC-related processing operations in the area. The anomalies resulted from elevated concentrations of radionuclides present in phosphate fertilizers, increased thorium in road-base gravel, and emanations from the radioactive storage site near the Latty Avenue airport. 9 refs., 3 figs.

Rodriguez, R E; Witt, D A; Cottrell, W D; Carrier, R F

1991-06-01T23:59:59.000Z

449

A Ubiquitous Optical Microsystem Platform with Application to Optical Metrology and Chemical Sensing  

E-Print Network [OSTI]

sensor platform for optical metrology and chemical sensing.Platform with Application to Optical Metrology and ChemicalPlatform with Application to Optical Metrology and Chemical

Gerling, John

2012-01-01T23:59:59.000Z

450

Double common-path interferometer for flexible optical probe of optical coherence tomography  

E-Print Network [OSTI]

J. Fujimoto, “Optical coherence tomography,” Science 254(D. E. N. Davies, “Optical coherence-domain reflectometry: afiber common-path optical coherence tomography: sensitivity

Park, Jae Seok; Chen, Zhongping; Jeong, Myung Yung; Kim, Chang-Seok

2012-01-01T23:59:59.000Z

451

Fiber optic geophysical sensors  

DOE Patents [OSTI]

A fiber optic geophysical sensor is described in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects. 2 figures.

Homuth, E.F.

1991-03-19T23:59:59.000Z

452

Integrated optical XY coupler  

DOE Patents [OSTI]

An integrated optical XY coupler having two converging input waveguide arms meeting in a central section and a central output waveguide arm and two diverging flanking output waveguide arms emanating from the central section. In-phase light from the input arms constructively interferes in the central section to produce a single mode output in the central output arm with the rest of the light being collected in the flanking output arms. Crosstalk between devices on a substrate is minimized by this collection of the out-of-phase light by the flanking output arms of the XY coupler. 9 figs.

Vawter, G.A.; Hadley, G.R.

1997-05-06T23:59:59.000Z

453

Integrated optical XY coupler  

DOE Patents [OSTI]

An integrated optical XY coupler having two converging input waveguide arms meeting in a central section and a central output waveguide arm and two diverging flanking output waveguide arms emanating from the central section. In-phase light from the input arms constructively interfers in the central section to produce a single mode output in the central output arm with the rest of the light being collected in the flanking output arms. Crosstalk between devices on a substrate is minimized by this collection of the out-of-phase light by the flanking output arms of the XY coupler.

Vawter, G. Allen (Albuquerque, NM); Hadley, G. Ronald (Albuquerque, NM)

1997-01-01T23:59:59.000Z

454

Laser-Scanning Coherent Anti-Stokes Raman Scattering Microscopy and Applications to Cell Biology  

E-Print Network [OSTI]

Laser-Scanning Coherent Anti-Stokes Raman Scattering Microscopy and Applications to Cell Biology Ji 11747-3157 USA ABSTRACT Laser-scanning coherent anti-Stokes Raman scattering (CARS) microscopy with fast., 1990). Duncan et al. constructed the first CARS microscope by use of two dye laser beams

Xie, Xiaoliang Sunney

455

CNT4704: Analysis of Computer Communication Networks (Fall 2014) Programming Assignment 3: Port Scanning Tool  

E-Print Network [OSTI]

CNT4704: Analysis of Computer Communication Networks (Fall 2014) Programming Assignment 3: Port will reinforce your socket programming knowledge and skill to generate a small but useful port scanning tool, which can scan a remote machine for a range of TCP ports in order to find which TCP services have been

Zou, Cliff C.

456

Scanning photo-induced impedance microscopy*/an impedance based imaging technique  

E-Print Network [OSTI]

Scanning photo-induced impedance microscopy*/an impedance based imaging technique Steffi Krause a technique, scanning photo-induced impedance micro- scopy (SPIM), suitable for the imaging of the complex Photoelectrochemistry has been used widely to study photo-thermally induced current changes at metal surfaces

Moritz, Werner

457

Automatic Reconstruction of Surfaces and Scalar Fields from 3D Scans1 2  

E-Print Network [OSTI]

dimensional (3D) points scan of its surface. Color, texture or some scalar material property of the physical) of a three-dimensional Delaunay Triangulation, its dual the three-dimensional Voronoi diagram, and dual uses with a more complex geometry, e.g. objects with holes, handles, pockets, cannot be scanned in a single pass

Xu, Guo-liang

458

Spectroscopic imaging from spatially-encoded single-scan multidimensional MRI data  

E-Print Network [OSTI]

Spectroscopic imaging from spatially-encoded single-scan multidimensional MRI data Assaf Tal, Lucio multidimensional magnetic resonance images within a single scan, based on a spatial encoding of the spin in its magnitude the spatial distribution of spins throughout the sample. It is hereby shown that whereas

Frydman, Lucio

459

Multi-atlas Segmentation in Head and Neck CT Scans Amelia M. Arbisser  

E-Print Network [OSTI]

Multi-atlas Segmentation in Head and Neck CT Scans by Amelia M. Arbisser B.S., Computer Science of Engineering Thesis Committee #12;2 #12;Multi-atlas Segmentation in Head and Neck CT Scans by Amelia M, we employ an atlas of labeled training images. We register each of these images to the unlabeled

Golland, Polina

460

Automatic Scan Prescription for Brain MRI T. Ernst, L. Itti, L. Chang  

E-Print Network [OSTI]

Automatic Scan Prescription for Brain MRI T. Ernst, L. Itti, L. Chang Harbor-UCLA Medical Center that allows the automatic prescription of brain MRI scans. This involves determination of the orientation of the current patient's brain, by matching his/her brain surface with a template brain surface. A desired

Itti, Laurent

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE-EDGE SCANNING MICROSCOPY  

E-Print Network [OSTI]

ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE- EDGE SCANNING MICROSCOPY A Thesis Science #12;ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE- EDGE SCANNING MICROSCOPY A Thesis) ______________________________ ______________________________ Ergun Akleman Valerie Taylor (Member) (Head of Department) December 2003 Major Subject: Computer Science

Keyser, John

462

Incorporating Multiple cDNA Microarray Slide Scans -Application to Somatic Embryogenesis in Maize  

E-Print Network [OSTI]

Incorporating Multiple cDNA Microarray Slide Scans -Application to Somatic Embryogenesis in Maize 1 the measurements of gene expression. Because `optimal' settings may vary from slide to slide, operators typically scan each slide multiple times and then choose the reading with the fewest over-exposed and under

463

Experimental Investigation of the Effect of Speckle Noise on Continuous Scan Laser Doppler Vibrometer Measurements  

E-Print Network [OSTI]

Period i : Phase Variable v : Voltage Signal fsamp : Sampling Frequency y : Response Signal fscan Research Building 1500 Engineering Drive Madison, WI 53706 Abstract Continuous Scan Laser Doppler when the scan frequency is high relative to the highest natural frequency of interest, and state

Allen, Matthew S.

464

Oxygen driven reconstruction dynamics of Ni,,977... measured by time-lapse scanning tunneling microscopy  

E-Print Network [OSTI]

Oxygen driven reconstruction dynamics of Ni,,977... measured by time-lapse scanning tunneling-lapse scanning tunneling microscopy STM has been used to observe the oxygen induced reconstruction behavior of Ni for the merging of steps in the presence of small amounts of adsorbed oxygen, less than 2% of a monolayer. Point

Sibener, Steven

465

Locating the Eyes in CT Brain Scan Data Kostis Kaggelides, Peter J. Elliott  

E-Print Network [OSTI]

, a technique for locating the eyes in Computed Tomography brain scan data, is described. The objective and implemented an algorithm which automaticallyidenti es and locates the eyes in a Computed Tomography(CT) brainLocating the Eyes in CT Brain Scan Data Kostis Kaggelides, Peter J. Elliott IBM UK Scienti c Centre

Fisher, Bob

466

Spatial optic multiplexer/diplexer  

DOE Patents [OSTI]

An apparatus for simultaneous transmission of optic signals having different wavelengths over a single optic fiber. Multiple light signals are transmitted through optic fibers that are formed into a circumference surrounding a central core fiber. The multiple light signals are directed by a lens into a single receiving fiber where the light combines and is then focused into the central core fiber which transmits the light to a wavelength discriminating receiver assembly.

Tremblay, Paul L. (Idaho Falls, ID)

1991-01-01T23:59:59.000Z

467

Optical Tweezer Arrays and Optical Substrates Created with Diffractive Optics Eric R. Dufresne and David G. Grier  

E-Print Network [OSTI]

Optical Tweezer Arrays and Optical Substrates Created with Diffractive Optics Eric R. Dufresne)) We describe a simple method for creating multiple optical tweezers from a single laser beam using diffractive optical elements. As a demonstration of this technique, we have implemented a 4 Ã? 4 square array

Grier, David

468

Optical Tweezer Arrays and Optical Substrates Created with Di#ractive Optics Eric R. Dufresne and David G. Grier  

E-Print Network [OSTI]

Optical Tweezer Arrays and Optical Substrates Created with Di#ractive Optics Eric R. Dufresne)) We describe a simple method for creating multiple optical tweezers from a single laser beam using di#ractive optical elements. As a demonstration of this technique, we have implemented a 4 Ã? 4 square array

Grier, David

469

High Temperature Optical Gas Sensing  

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

Optical Gas Sensing Optical Gas Sensing Opportunity Research is active on optical sensors integrated with advanced sensing materials for high temperature embedded gas sensing applications. Patent applications have been filed for two inventions in this area and several other methods are currently under development. These technologies are available for licensing and/or further collaborative research from the U.S. Department of Energy's National Energy Technology Laboratory (NETL). Organizations or individuals with capabilities in optical sensor packaging for harsh environment and high temperature applications are encouraged to contact NETL to explore potential collaborative opportunities. Overview Contact NETL Technology Transfer Group techtransfer@netl.doe.gov

470

Optical Airborne Particle Counter Operation  

Science Journals Connector (OSTI)

For most cleanroom airborne particle measurements, an optical single particle ... or surrogates of the product or of the cleanroom environment. The last procedure is used to...

Alvin Lieberman

1992-01-01T23:59:59.000Z

471

Optically stimulated differential impedance spectroscopy  

DOE Patents [OSTI]

Methods and apparatuses for evaluating a material are described. Embodiments typically involve use of an impedance measurement sensor to measure the impedance of a sample of the material under at least two different states of illumination. The states of illumination may include (a) substantially no optical stimulation, (b) substantial optical stimulation, (c) optical stimulation at a first wavelength of light, (d) optical stimulation at a second wavelength of light, (e) a first level of light intensity, and (f) a second level of light intensity. Typically a difference in impedance between the impedance of the sample at the two states of illumination is measured to determine a characteristic of the material.

Maxey, Lonnie C; Parks, II, James E; Lewis, Sr., Samuel A; Partridge, Jr., William P

2014-02-18T23:59:59.000Z

472

Optical imaging of Rydberg atoms .  

E-Print Network [OSTI]

??We present an experiment exploring electromagnetically induced transparency (EIT) in Rydberg atoms in order to observe optical nonlinearities at the single photon level. ??Rb atoms… (more)

Mazurenko, Anton

2012-01-01T23:59:59.000Z

473

Phase correlations and optical coherence  

Science Journals Connector (OSTI)

We examine the properties of the recently introduced degrees of coherence regarding the phase correlations of the optical field. It is seen that some of these quantities are...

Tervo, Jani; Setälä, Tero; Friberg, Ari T

2012-01-01T23:59:59.000Z

474

Efficiencies of Quantum Optical Detectors  

E-Print Network [OSTI]

We propose a definition for the efficiency that can be universally applied to all classes of quantum optical detectors. This definition is based on the maximum amount of optical loss that a physically plausible device can experience while still replicating the properties of a given detector. We prove that detector efficiency cannot be increased using linear optical processing. That is, given a set of detectors, as well as arbitrary linear optical elements and ancillary light sources, it is impossible to construct detection devices that would exhibit higher efficiencies than the initial set.

Daniel Hogg; Dominic W. Berry; A. I. Lvovsky

2014-12-15T23:59:59.000Z

475

Sandia National Laboratories: Optics Lab  

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

Engine Test Facility Central Receiver Test Facility Power Towers for Utilities Solar Furnace Dish Test Facility Optics Lab Parabolic Dishes Work For Others (WFO) User...

476

V-101: McAfee VirusScan Enterprise Lets Local Users Gain Elevated  

Broader source: Energy.gov (indexed) [DOE]

1: McAfee VirusScan Enterprise Lets Local Users Gain Elevated 1: McAfee VirusScan Enterprise Lets Local Users Gain Elevated Privileges V-101: McAfee VirusScan Enterprise Lets Local Users Gain Elevated Privileges February 28, 2013 - 12:05am Addthis PROBLEM: McAfee VirusScan Enterprise Lets Local Users Gain Elevated Privileges PLATFORM: VSE 8.8 Patch 2 with Access Protection, including Self Protection, turned off ABSTRACT: A vulnerability was reported in McAfee VirusScan Enterprise. REFERENCE LINKS: McAfee Security Bulletins ID: SB10038 SecurityTracker Alert ID: 1028209 IMPACT ASSESSMENT: Medium DISCUSSION: When Access Protection has been disabled, a local user can gain full control of the target application IMPACT: A local user can obtain elevated privileges on the target system. SOLUTION: The vendor has issued a fix (8.8 Patch 2 with HF778101, 8.8 Patch 3)

477

U-263: Trend Micro InterScan Messaging Security Flaws Permit Cross-Site  

Broader source: Energy.gov (indexed) [DOE]

3: Trend Micro InterScan Messaging Security Flaws Permit 3: Trend Micro InterScan Messaging Security Flaws Permit Cross-Site Scripting and Cross-Site Request Forgery Attacks U-263: Trend Micro InterScan Messaging Security Flaws Permit Cross-Site Scripting and Cross-Site Request Forgery Attacks September 19, 2012 - 6:00am Addthis PROBLEM: Trend Micro InterScan Messaging Security Flaws Permit Cross-Site Scripting and Cross-Site Request Forgery Attacks PLATFORM: 7.1-Build_Win32_1394; possibly other versions ABSTRACT: A vulnerability was reported in Trend Micro InterScan Messaging Security. reference LINKS: US CERT Vulnerability Note VU#471364 SecurityTracker Alert ID: 1027544 CVE-2012-2995 CVE-2012-2996 Micro Trend IMPACT ASSESSMENT: Medium Discussion: Several scripts do not properly filter HTML code from user-supplied input

478

V-101: McAfee VirusScan Enterprise Lets Local Users Gain Elevated  

Broader source: Energy.gov (indexed) [DOE]

1: McAfee VirusScan Enterprise Lets Local Users Gain Elevated 1: McAfee VirusScan Enterprise Lets Local Users Gain Elevated Privileges V-101: McAfee VirusScan Enterprise Lets Local Users Gain Elevated Privileges February 28, 2013 - 12:05am Addthis PROBLEM: McAfee VirusScan Enterprise Lets Local Users Gain Elevated Privileges PLATFORM: VSE 8.8 Patch 2 with Access Protection, including Self Protection, turned off ABSTRACT: A vulnerability was reported in McAfee VirusScan Enterprise. REFERENCE LINKS: McAfee Security Bulletins ID: SB10038 SecurityTracker Alert ID: 1028209 IMPACT ASSESSMENT: Medium DISCUSSION: When Access Protection has been disabled, a local user can gain full control of the target application IMPACT: A local user can obtain elevated privileges on the target system. SOLUTION: The vendor has issued a fix (8.8 Patch 2 with HF778101, 8.8 Patch 3)

479

Design of a scanning Josephson junction microscope for submicron-resolution magnetic imaging  

SciTech Connect (OSTI)

We describe a magnetic field scanning instrument designed to extend the spatial resolution of scanning superconducting quantum interference device microscopy into the submicron regime. This instrument, the scanning Josephson junction microscope, scans a single Josephson junction across the surface of a sample, detecting the local magnetic field by the modulation of the junction critical current. By using a submicron junction and a scanning tunneling microscope feedback system to maintain close proximity to the surface, magnetic field sensitivity of 10 {mu}G with a spatial resolution of 0.3 {mu}m should be attainable, opening up new opportunities for imaging vortex configurations and core structure in superconductors and magnetic domains in magnetic materials. {copyright} {ital 1999 American Institute of Physics.}

Plourde, B.L.; Van Harlingen, D.J. [Department of Physics, Science and Technology Center for Superconductivity, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)] [Department of Physics, Science and Technology Center for Superconductivity, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

1999-11-01T23:59:59.000Z

480

Optical oxygen concentration monitor  

DOE Patents [OSTI]

A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen`s A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2,000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest. 4 figs.

Kebabian, P.

1997-07-22T23:59:59.000Z

Note: This page contains sample records for the topic "near-field scanning optical" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Optical oxygen concentration monitor  

DOE Patents [OSTI]

A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen's A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest.

Kebabian, Paul (Acton, MA)

1997-01-01T23:59:59.000Z

482

Optical transcutaneous bilirubin detector  

DOE Patents [OSTI]

This invention consists of a transcutaneous bilirubin detector comprising a source of light having spectral components absorbable and not absorbable by bilirubin, a handle assembly, electronic circuitry and a fiber optic bundle connecting the assembly to the light source and circuitry. Inside the assembly is a prism that receives the light from one end of the fiber optic bundle and directs it onto the skin and directs the reflected light back into the bundle. The other end of the bundle is trifucated, with one end going to the light source and the other two ends going to circuitry that determines how much light of each kind has been reflected. A relatively greater amount absorbed by the skin from the portion of the spectrum absorbable by bilirubin may indicate the presence of the illness. Preferably, two measurements are made, one on the kneecap and one on the forehead, and compared to determine the presence of bilirubin. To reduce the impact of light absorption by hemoglobin in the blood carried by the skin, pressure is applied with a plunger and spring in the handle assembly, the pressure limited by points of a button slidably carried in the assembly that are perceived by touch when the pressure applied is sufficient.

Kronberg, J.W.

1991-03-04T23:59:59.000Z

483

Optical cavity furnace for semiconductor wafer processing  

DOE Patents [OSTI]

An optical cavity furnace 10 having multiple optical energy sources 12 associated with an optical cavity 18 of the furnace. The multiple optical energy sources 12 may be lamps or other devices suitable for producing an appropriate level of optical energy. The optical cavity furnace 10 may also include one or more reflectors 14 and one or more walls 16 associated with the optical energy sources 12 such that the reflectors 14 and walls 16 define the optical cavity 18. The walls 16 may have any desired configuration or shape to enhance operation of the furnace as an optical cavity 18. The optical energy sources 12 may be positioned at any location with respect to the reflectors 14 and walls defining the optical cavity. The optical cavity furnace 10 may further include a semiconductor wafer transport system 22 for transporting one or more semiconductor wafers 20 through the optical cavity.

Sopori, Bhushan L.

2014-08-05T23:59:59.000Z

484

CHARACTERISATION OF SEMICONDUCTOR OPTICAL AMPLIFIERS FOR ALL-OPTICAL REGENERATION  

E-Print Network [OSTI]

electrical pumping, broad spectral range and opportunities for integration and mass production. Among these components, the semiconductor optical amplifier (SOA) with gain saturation, low optical and electrical power Various SOAs from Alcatel-Thales III-V lab were characterized in the framework of the French project FUTUR

Paris-Sud XI, Université de

485

Quantum Optical Version of Classical Optical Transformations and Beyond  

E-Print Network [OSTI]

By the newly developed technique of integration within an ordered product (IWOP) of operators, we explore quantum optical version of classical optical transformations such as optical Fresnel transform, Hankel transform, fractional Fourier transform, Wigner transform, wavelet transform and Fresnel-Hadmard combinatorial transform etc. In this way one may gain benefit for developing classical optics theory from the research in quantum optics, or vice-versa. We can not only find some new quantum mechanical unitary operators which correspond to the known optical transformations, deriving a new theorem for calculating quantum tomogram of density operators, but also can reveal some new classical optical transformations. We derive GFO's normal product form and its canonical coherent state representation and find that GFO is the loyal representation of symplectic group multiplication rule. We show that GFT is just the transformation matrix element of GFO in the coordinate representation such that two successive GFTs is still a GFT. The ABCD rule of the Gaussian beam propagation is directly demonstrated in the context of quantum optics. Especially, the introduction of quantum mechanical entangled state representations opens up a new area to finding new classical optical transformations. The complex wavelet transform and the condition of mother wavelet are studied in the context of quantum optics too. Throughout our discussions, the coherent state, the entangled state representation of the two-mode squeezing operators and the IWOP technique are fully used. All these confirms Dirac's assertion: " ... for a quantum dynamic system that has a classical analogue, unitary transformation in the quantum theory is the analogue of contact transformation in the classical theory".

Hong-yi Fan; Li-yun Hu

2010-10-03T23:59:59.000Z

486

Optical forces and optical torques on various materials arising from optical lattices in the Lorentz-Mie regime  

E-Print Network [OSTI]

By combining the Maxwell stress tensor with the finite-difference time-domain (FDTD) method, we calculate the optical force and optical torque on particles from optical lattices. We compare our method to the two-component ...

Jia, Lin

487

Nonlinear optical properties of ZnO/poly (vinyl alcohol) nanocomposite films  

SciTech Connect (OSTI)

Extensive studies have already been reported on the optical characteristics of ZnO/polymer nanocomposite films, using a variety of polymers including transparent polymers such as polystyrene, polymethyl methacrylate etc and many interesting results have been established regarding the non linear optical characteristics of these systems. Poly (vinyl alcohol)(PVA) is a water soluble polymer. Though the structural and optical studies of ZnO/PVA nanocomposite films have already been investigated, there are no detailed reports on the nonlinear optical characteristics of ZnO/PVA nanocomposite films, irrespective of the fact that these nanocomposite films can be synthesized using quite easy and cost effective methods. The present work is an attempt to study in detail the nonlinear optical behaviour of ZnO/PVA nanocomposite films using Z-scan technique. Highly transparent ZnO/PVA nanocomposite films were prepared from the ZnO incorporated PVA solution in water using spin coating technique. The ZnO nanoparticles were synthesized by the simple chemical route at room temperature. High-resolution transmission electron microscopy studies show that the ZnO nanoparticles are of size around 10 nm. The ZnO/PVA nanocomposite films were structurally characterized by X-ray diffraction technique, from which the presence of both PVA and ZnO in the nanocomposite was established. The optical absorptive nonlinearity in the nanocomposite films was investigated using open aperture Z-scan technique. The results indicate optical limiting type nonlinearity in the films due to two photon absorption in ZnO with efficiency more than 50%. These films also show a self defocusing type negative nonlinear refraction in closed aperture Z-scan experiment. The present studies indicate that, highly transparent and homogeneous films of ZnO/PVA nanocomposite can be obtained on glass substrates using simple methods, in a highly cost effective way, since PVA is water soluble. These nanocomposite films offer prospects of application as efficient optical limiters to protect light sensitive devices from the possible damage on exposure to high intensity radiation.

Jeeju, P. P., E-mail: jeejupp@gmail.com [Department of Physics, S N M College, Maliankara, Ernakulam, Kerala (India); Jayalekshmi, S., E-mail: jayalekshmi@cusat.ac.in [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Kochi 682 022 (India); Chandrasekharan, K. [Department of Physics, National Institute of Technology, Calicut, Kerala (India)

2014-01-28T23:59:59.000Z

488

Optical characteristics of pulsed laser deposited Ge-Sb-Te thin films studied by spectroscopic ellipsometry  

SciTech Connect (OSTI)

Pulsed laser deposition technique was used for the fabrication of (GeTe){sub 1-x}(Sb{sub 2}Te{sub 3}){sub x} (x = 0, 0.33, 0.50, 0.66, and 1) amorphous thin films. Scanning electron microscopy with energy-dispersive x-ray analysis, x-ray diffraction, optical reflectivity, and sheet resistance temperature dependences as well as variable angle spectroscopic ellipsometry measurements were used to characterize as-deposited (amorphous) and annealed (rocksaltlike) layers. In order to extract optical functions of the films, the Cody-Lorentz model was applied for the analysis of ellipsometric data. Fitted sets of Cody-Lorentz model parameters are discussed in relation with chemical composition and the structure of the layers. The GeTe component content was found to be responsible for the huge optical functions and thickness changes upon amorphous-to-fcc phase transition.

Nemec, P. [Department of Graphic Arts and Photophysics, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Prikryl, J.; Frumar, M. [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Nazabal, V. [Equipe Verres et Ceramiques, UMR-CNRS 6226, Sciences Chimiques de Rennes (SCR), Universite de Rennes 1, 35042 Rennes Cedex (France)

2011-04-01T23:59:59.000Z

489

Probing the electronic structure and optical response of a graphene quantum disk supported on monolayer graphene  

SciTech Connect (OSTI)

In this paper, we show that a graphene quantum disk (GQD) can be generated on monolayer graphene via structural modification using the electron beam. The electronic structure and local optical responses of the GQD, supported on monolayer graphene, were probed with electron energy-loss spectrum imaging on an aberration-corrected scanning transmission electron microscope. We observe that for small GQD, {approx}1.3 nm in diameter, the electronic structure and optical response are governed by the dominating edge states, and are distinctly different from either monolayer graphene or double-layer graphene. Highly localized plasmon modes are generated at the GQD due to the confinement from the edge of the GQD in all directions. The highly localized optical response from GQDs could find use in designing nanoscale optoelectronic and plasmonic devices based on monolayer graphene.

Zhou, Wu [Vanderbilt University; Pennycook, Stephen J [ORNL; Idrobo Tapia, Juan C [ORNL

2012-01-01T23:59:59.000Z

490

Optical nonlinear absorption characteristics of Sb{sub 2}Se{sub 3} nanoparticles  

SciTech Connect (OSTI)

In this work, we report for the first time, the nonlinear optical absorption properties of antimony selenide (Sb{sub 2}Se{sub 3}) nanoparticles synthesized through solvothermal route. X-ray diffraction results revealed the crystalline nature of the nanoparticles. Electron microscopy studies revealed that the nanoparticles are in the range of 10 - 40 nm. Elemental analysis was performed using EDAX. By employing open aperture z-scan technique, we have evaluated the effective two-photon absorption coefficient of Sb{sub 2}Se{sub 3} nanoparticles to be 5e-10 m/W at 532 nm. These nanoparticles exhibit strong intensity dependent nonlinear optical absorption and hence could be considered to have optical power limiting applications in the visible range.

Muralikrishna, Molli, E-mail: muralikrishnamolli@sssihl.edu.in; Kiran, Aditha Sai, E-mail: muralikrishnamolli@sssihl.edu.in; Ravikanth, B., E-mail: muralikrishnamolli@sssihl.edu.in; Sowmendran, P., E-mail: muralikrishnamolli@sssihl.edu.in; Muthukumar, V. Sai, E-mail: muralikrishnamolli@sssihl.edu.in; Venkataramaniah, Kamisetti, E-mail: muralikrishnamolli@sssihl.edu.in [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India)

2014-04-24T23:59:59.000Z

491

Process for rapid detection of fratricidal defects on optics using Linescan Phase Differential Imaging  

SciTech Connect (OSTI)

Phase-defects on optics used in high-power lasers can cause light intensification leading to laser-induced damage of downstream optics. We introduce Linescan Phase Differential Imaging (LPDI), a large-area dark-field imaging technique able to identify phase-defects in the bulk or surface of large-aperture optics with a 67 second scan-time. Potential phase-defects in the LPDI images are indentified by an image analysis code and measured with a Phase Shifting Diffraction Interferometer (PSDI). The PSDI data is used to calculate the defects potential for downstream damage using an empirical laser-damage model that incorporates a laser propagation code. A ray tracing model of LPDI was developed to enhance our understanding of its phase-defect detection mechanism and reveal limitations.

Ravizza, F L; Nostrand, M C; Kegelmeyer, L M; Hawley, R A; Johnson, M A

2009-11-05T23:59:59.000Z

492

Semiconductor-based optical refrigerator  

DOE Patents [OSTI]

Optical refrigerators using semiconductor material as a cooling medium, with layers of material in close proximity to the cooling medium that carries away heat from the cooling material and preventing radiation trapping. In addition to the use of semiconducting material, the invention can be used with ytterbium-doped glass optical refrigerators.

Epstein, Richard I. (Santa Fe, NM); Edwards, Bradley C. (Nekoosa, WI); Sheik-Bahae, Mansoor (Albuquerque, NM)

2002-01-01T23:59:59.000Z

493

Bi-stable optical actuator  

DOE Patents [OSTI]

The present invention is a bi-stable optical actuator device that is depowered in both stable positions. A bearing is used to transfer motion and smoothly transition from one state to another. The optical actuator device may be maintained in a stable position either by gravity or a restraining device.

Holdener, Fred R. (Tracy, CA); Boyd, Robert D. (Livermore, CA)

2000-01-01T23:59:59.000Z

494

New Types of Optical Glass  

Science Journals Connector (OSTI)

... IN view of the interest shown in new optical glasses recently produced in Great Britain and in the United States, we wish to summarize ... probable lines of development. Advances in lens design have led to a demand for new glasses with optical properties different from those available hitherto as outlined in a recent paper by ...

W. M. HAMPTON; R. E. BASTICK; W. N. WHEAT

1944-03-04T23:59:59.000Z

495

Optical Signal Processing in All-Optical Packet Routing Systems S. J. Ben Yoo  

E-Print Network [OSTI]

Optical Signal Processing in All-Optical Packet Routing Systems S. J. Ben Yoo Department@ece.ucdavis.edu, Abstract: This paper discusses important signal processing functions in all-optical packet routing systems. We will pay special attention to all-optical time-to-live, optical performance monitoring, optical

Kolner, Brian H.

496

Optical Approach to Gravitational Redshift  

E-Print Network [OSTI]

An optical approach begins by interpreting the gravitational redshift resulting to a change in the relative velocity of light due to the medium of propagation in the gravitational field. The discussion continues by pointing out an agreement in structure between the equation for rays in geometrical optics and the geodesic equation of general relativity. From their comparison we learn that the path of rays should be given by the relation $ds^2=n^2(r)dr^2+r^2d\\theta^2$, not by $ds^2=dr^2+r^2d\\theta^2$, in a medium with spherical symmetry of refractive index $n(r)$. The development of an optical analogy suggests introducing $n^2(r)$ in place of $g_{rr}$ as an optical version of the Schwarzschild metric. In form and content, $n^2(r)$ is different from $g_{rr}$. The optical point of view replaces the general-relativity explanations in terms of time and gravitation.

Y. G. Yi

2012-04-12T23:59:59.000Z

497

Argonne CNM: 2010 Seminar Series  

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

10 10 2013 | 2012 | 2011 | 2010 | 2009 | 2008 | 2007 | 2006 | 2005 | 2004 | 2003 December 17, 2010 "Microsystems for Control of Light-Matter Interaction at the Nanoscale," Il Woong Jung, hosted by Daniel Lopez Abstract: It has been shown that electromagnetic fields incident upon metal particles can be confined over dimensions on the order of or smaller than the wavelength of light. This strong light-matter interaction leads to an enhanced optical near-field at metallic interfaces or in small metallic nanostructures. These highly enhanced fields can be used to probe materials with subwavelength resolution (near-field scanning optical microscopy) and allow single-molecule surface-enhanced Raman spectroscopy detection. The ability to control these interactions (i.e., tune the plasmonic resonance) is highly desirable for developing ultrasensitive Raman and fluorescence detectors, highly efficient optical antennas, tunable single-emitters, nano-patterning, and novel nanophotonic devices.

498

Toward single-cycle optical pulses  

E-Print Network [OSTI]

Single-cycle optical pulses, the never-before-achieved regime, have a great potential for attosecond science and phase-sensitive nonlinear optics. To achieve single-cycle optical pulses by active synchronization, three ...

Kim, Jung-Won, 1976-

2004-01-01T23:59:59.000Z

499

Development of optical field emitter arrays  

E-Print Network [OSTI]

Optical field emitters are electron emission sources actuated by incident light. Optically actuated field emitters may produce ultrafast pulses of electrons when excited by ultrafast optical pulses, thus making them of ...

Yang, Yujia, S.M. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

500

Near Field Modeling of the Effects of Sound Barriers on Flow and Dispersion  

E-Print Network [OSTI]

vertical loft and speed of the plume at various fan and wind speeds.on low wind speeds and due to the increased vertical spreador vertical plume spread. Under low wind speed conditions (

Gazzolo, Brandn

2012-01-01T23:59:59.000Z