National Library of Energy BETA

Sample records for regional optics photonics

  1. SPIE Optics + Photonics 2011

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

    SPIE Optics + Photonics 2011 August 21-25, 2011 San Diego Convention Center San Diego

  2. Optics of globular photonic crystals

    SciTech Connect (OSTI)

    Gorelik, V S

    2007-05-31

    The results of experimental and theoretical studies of the optical properties of globular photonic crystals - new physical objects having a crystal structure with the lattice period exceeding considerably the atomic size, are presented. As globular photonic crystals, artificial opal matrices consisting of close-packed silica globules of diameter {approx}200 nm were used. The reflection spectra of these objects characterising the parameters of photonic bands existing in these crystals in the visible spectral region are presented. The idealised models of the energy band structure of photonic crystals investigated in the review give analytic dispersion dependences for the group velocity and the effective photon mass in a globular photonic crystal. The characteristics of secondary emission excited in globular photonic crystals by monochromatic and broadband radiation are presented. The results of investigations of single-photon-excited delayed scattering of light observed in globular photonic crystals exposed to cw UV radiation and radiation from a repetitively pulsed copper vapour laser are presented. The possibilities of using globular photonic crystals as active media for lasing in different spectral regions are considered. It is proposed to use globular photonic crystals as sensitive sensors in optoelectronic devices for molecular analysis of organic and inorganic materials by the modern methods of laser spectroscopy. The results of experimental studies of spontaneous and stimulated globular scattering of light are discussed. The conditions for observing resonance and two-photon-excited delayed scattering of light are found. The possibility of accumulation and localisation of the laser radiation energy inside a globular photonic crystal is reported. (review)

  3. Silicon Photonics for Low- Energy Optical Communications

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

    Photonics for Low- Energy Optical Communications To support the needs of next generation of optical communications, researchers have developed a Sandia Silicon Photonics platform that leverages the semiconductor and nanotechnology capabilities of Sandia's Microsystems and Engineering Sciences Applications (MESA) complex to reduce the power dissipation of interconnects within digital systems. Improving Interconnection Performance As integrated circuit chips now incorporate over a billion

  4. Optical trapping apparatus, methods and applications using photonic crystal resonators

    DOE Patents [OSTI]

    Erickson, David; Chen, Yih-Fan

    2015-06-16

    A plurality of photonic crystal resonator optical trapping apparatuses and a plurality optical trapping methods using the plurality of photonic crystal resonator optical trapping apparatuses include located and formed over a substrate a photonic waveguide that is coupled (i.e., either separately coupled or integrally coupled) with a photonic crystal resonator. In a particular embodiment, the photonic waveguide and the photonic crystal resonator comprise a monocrystalline silicon (or other) photonic material absent any chemical functionalization. In another particular embodiment, the photonic waveguide and the photonic crystal resonator comprise a silicon nitride material which when actuating the photonic crystal resonator optical trapping apparatus with a 1064 nanometer resonant photonic radiation wavelength (or other resonant photonic radiation wavelength in a range from about 700 to about 1200 nanometers) provides no appreciable heating of an aqueous sample fluid that is analyzed by the photonic crystal resonator optical trapping apparatus.

  5. Optical amplification enhancement in photonic crystals

    SciTech Connect (OSTI)

    Sapienza, R.; Leonetti, M.; Froufe-Perez, L. S.; Galisteo-Lopez, J. F.; Lopez, C.; Conti, C.

    2011-02-15

    Improving and controlling the efficiency of a gain medium is one of the most challenging problems of laser research. By measuring the gain length in an opal-based photonic crystal doped with laser dye, we demonstrate that optical amplification is more than twenty-fold enhanced along the {Gamma}-K symmetry directions of the face-centered-cubic photonic crystal. These results are theoretically explained by directional variations of the density of states, providing a quantitative connection between density of the states and light amplification.

  6. Optical isolation via unidirectional resonant photon tunneling

    SciTech Connect (OSTI)

    Moccia, Massimo; Castaldi, Giuseppe; Galdi, Vincenzo; Al, Andrea; Engheta, Nader

    2014-01-28

    We show that tri-layer structures combining epsilon-negative and magneto-optical material layers can exhibit unidirectional resonant photon tunneling phenomena that can discriminate between circularly polarized (CP) waves of given handedness impinging from opposite directions, or between CP waves with different handedness impinging from the same direction. This physical principle, which can also be interpreted in terms of a Fabry-Perot-type resonance, may be utilized to design compact optical isolators for CP waves. Within this framework, we derive simple analytical conditions and design formulae, and quantitatively assess the isolation performance, also taking into account the unavoidable imperfections and nonidealities.

  7. Use of a photonic crystal for optical amplifier gain control

    DOE Patents [OSTI]

    Lin, Shawn-Yu; Fleming, James G.; El-Kady, Ihab

    2006-07-18

    An optical amplifier having a uniform gain profile uses a photonic crystal to tune the density-of-states of a gain medium so as to modify the light emission rate between atomic states. The density-of-states of the gain medium is tuned by selecting the size, shape, dielectric constant, and spacing of a plurality of microcavity defects in the photonic crystal. The optical amplifier is particularly useful for the regeneration of DWDM signals in long optical fibers.

  8. Passive thermo-optic feedback for robust athermal photonic systems

    DOE Patents [OSTI]

    Rakich, Peter T.; Watts, Michael R.; Nielson, Gregory N.

    2015-06-23

    Thermal control devices, photonic systems and methods of stabilizing a temperature of a photonic system are provided. A thermal control device thermally coupled to a substrate includes a waveguide for receiving light, an absorption element optically coupled to the waveguide for converting the received light to heat and an optical filter. The optical filter is optically coupled to the waveguide and thermally coupled to the absorption element. An operating point of the optical filter is tuned responsive to the heat from the absorption element. When the operating point is less than a predetermined temperature, the received light is passed to the absorption element via the optical filter. When the operating point is greater than or equal to the predetermined temperature, the received light is transmitted out of the thermal control device via the optical filter, without being passed to the absorption element.

  9. Suppressing spectral diffusion of emitted photons with optical pulses

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

    Fotso, H. F.; Feiguin, A. E.; Awschalom, D. D.; Dobrovitski, V. V.

    2016-01-22

    In many quantum architectures the solid-state qubits, such as quantum dots or color centers, are interfaced via emitted photons. However, the frequency of photons emitted by solid-state systems exhibits slow uncontrollable fluctuations over time (spectral diffusion), creating a serious problem for implementation of the photon-mediated protocols. Here we show that a sequence of optical pulses applied to the solid-state emitter can stabilize the emission line at the desired frequency. We demonstrate efficiency, robustness, and feasibility of the method analytically and numerically. Taking nitrogen-vacancy center in diamond as an example, we show that only several pulses, with the width of 1more » ns, separated by few ns (which is not difficult to achieve) can suppress spectral diffusion. As a result, our method provides a simple and robust way to greatly improve the efficiency of photon-mediated entanglement and/or coupling to photonic cavities for solid-state qubits.« less

  10. Multipoint photonic doppler velocimetry using optical lens elements

    DOE Patents [OSTI]

    Frogget, Brent Copely; Romero, Vincent Todd

    2014-04-29

    A probe including a fisheye lens is disclosed to measure the velocity distribution of a moving surface along many lines of sight. Laser light, directed to the surface and then reflected back from the surface, is Doppler shifted by the moving surface, collected into fisheye lens, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to an index-matching lens and eventually to a fisheye lens. The fiber array flat polished and coupled to the index-matching lens using index-matching gel. Numerous fibers in a fiber array project numerous rays through the fisheye lens which in turn project many measurement points at numerous different locations to establish surface coverage over a hemispherical shape with very little crosstalk.

  11. Optical microscope using an interferometric source of two-color, two-beam entangled photons

    DOE Patents [OSTI]

    Dress, William B.; Kisner, Roger A.; Richards, Roger K.

    2004-07-13

    Systems and methods are described for an optical microscope using an interferometric source of multi-color, multi-beam entangled photons. A method includes: downconverting a beam of coherent energy to provide a beam of multi-color entangled photons; converging two spatially resolved portions of the beam of multi-color entangled photons into a converged multi-color entangled photon beam; transforming at least a portion of the converged multi-color entangled photon beam by interaction with a sample to generate an entangled photon specimen beam; and combining the entangled photon specimen beam with an entangled photon reference beam within a single beamsplitter. An apparatus includes: a multi-refringent device providing a beam of multi-color entangled photons; a condenser device optically coupled to the multi-refringent device, the condenser device converging two spatially resolved portions of the beam of multi-color entangled photons into a converged multi-color entangled photon beam; a beam probe director and specimen assembly optically coupled to the condenser device; and a beam splitter optically coupled to the beam probe director and specimen assembly, the beam splitter combining an entangled photon specimen beam from the beam probe director and specimen assembly with an entangled photon reference beam.

  12. Optical nonreciprocal transmission in an asymmetric silicon photonic crystal structure

    SciTech Connect (OSTI)

    Wu, Zheng; Chen, Juguang; Ji, Mengxi; Huang, Qingzhong; Xia, Jinsong; Wang, Yi E-mail: ywangwnlo@mail.hust.edu.cn; Wu, Ying E-mail: ywangwnlo@mail.hust.edu.cn

    2015-11-30

    An optical nonreciprocal transmission (ONT) is realized by employing the nonlinear effects in a compact asymmetric direct-coupled nanocavity-waveguide silicon photonic crystal structure with a high loaded quality factor (Q{sub L}) of 42 360 and large extinction ratio exceeding 30 dB. Applying a single step lithography and successive etching, the device can realize the ONT in an individual nanocavity, alleviating the requirement to accurately control the resonance of the cavities. A maximum nonreciprocal transmission ratio of 21.1 dB as well as a working bandwidth of 280 pm in the telecommunication band are obtained at a low input power of 76.7 μW. The calculated results by employing a nonlinear coupled-mode model are in good agreement with the experiment.

  13. Optical Properties and Wave Propagation in Semiconductor-Based Two-Dimensional Photonic Crystals

    SciTech Connect (OSTI)

    Mario Agio

    2002-12-31

    This work is a theoretical investigation on the physical properties of semiconductor-based two-dimensional photonic crystals, in particular for what concerns systems embedded in planar dielectric waveguides (GaAs/AlGaAs, GaInAsP/InP heterostructures, and self-standing membranes) or based on macro-porous silicon. The photonic-band structure of photonic crystals and photonic-crystal slabs is numerically computed and the associated light-line problem is discussed, which points to the issue of intrinsic out-of-lane diffraction losses for the photonic bands lying above the light line. The photonic states are then classified by the group theory formalism: each mode is related to an irreducible representation of the corresponding small point group. The optical properties are investigated by means of the scattering matrix method, which numerically implements a variable-angle-reflectance experiment; comparison with experiments is also provided. The analysis of surface reflectance proves the existence of selection rules for coupling an external wave to a certain photonic mode. Such rules can be directly derived from symmetry considerations. Lastly, the control of wave propagation in weak-index contrast photonic-crystal slabs is tackled in view of designing building blocks for photonic integrated circuits. The proposed designs are found to comply with the major requirements of low-loss propagation, high and single-mode transmission. These notions are then collected to model a photonic-crystal combiner for an integrated multi-wavelength-source laser.

  14. Emergence of Artificial Photons in an Optical Lattice

    SciTech Connect (OSTI)

    Tewari, Sumanta; Scarola, V. W.; Sarma, S. Das; Senthil, T.

    2006-11-17

    We establish the theoretical feasibility of direct analog simulation of the compact U(1) lattice gauge theories in optical lattices with dipolar bosons. We discuss the realizability of the topological Coulomb phase in extended Bose-Hubbard models in several optical lattice geometries. We predict the testable signatures of this emergent phase in noise correlation measurements, thus suggesting the possible emergence of artificial light in optical lattices.

  15. A versatile optical junction using photonic band-gap guidance and self collimation

    SciTech Connect (OSTI)

    Gupta, Man Mohan; Medhekar, Sarang

    2014-09-29

    We show that it is possible to design two photonic crystal (PC) structures such that an optical beam of desired wavelength gets guided within the line defect of the first structure (photonic band gap guidance) and the same beam gets guided in the second structure by self-collimation. Using two dimensional simulation of a design made of the combination of these two structures, we propose an optical junction that allows for crossing of two optical signals of same wavelength and same polarization with very low crosstalk. Moreover, the junction can be operated at number of frequencies in a wide range. Crossing of multiple beams with very low cross talk is also possible. The proposed junction should be important in future integrated photonic circuits.

  16. Superconducting nanowire single-photon detectors integrated with optical nano-antennae

    SciTech Connect (OSTI)

    Hu, X.; Dauler, E.; Molnar, R.; Berggren, K. K.

    2010-12-20

    Optical nano-antennae have been integrated with semiconductor lasers to intensify light at the nanoscale and photodiodes to enhance photocurrent. In quantum optics, plasmonic metal structures have been used to enhance nonclassical light emission from single quantum dots. Absorption and detection of single photons from free space could also be enhanced by nanometallic antennae, but this has not previously been demonstrated. Here, we use nano-optical transmission effects in a one-dimensional gold structure, combined with optical cavity resonance, to form optical nano-antennae, which are further used to couple single photons from free space into a 80-nm-wide superconducting nanowire. This antenna-assisted coupling enables a superconducting nanowire single-photon detector with 47% device efficiency at the wavelength of 1550 nm and 9-?m-by-9-?m active area while maintaining a reset time of only 5 ns. We demonstrate nanoscale antenna-like structures to achieve exceptional efficiency and speed in single-photon detection.

  17. Breakthroughs in photonics 2013: X-ray optics

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

    Soufli, Regina

    2014-04-01

    Here, this review discusses the latest advances in extreme ultraviolet/X-ray optics development, which are motivated by the availability and demands of new X-ray sources and scientific and industrial applications. Among the breakthroughs highlighted are the following: i) fabrication, metrology, and mounting technologies for large-area optical substrates with improved figure, roughness, and focusing properties; ii) multilayer coatings with especially optimized layer properties, achieving improved reflectance, stability, and out-of-band suppression; and iii) nanodiffractive optics with improved efficiency and resolution.

  18. Radio frequency phototube and optical clock: High resolution, high rate and highly stable single photon timing technique

    SciTech Connect (OSTI)

    Margaryan, Amur

    2011-10-01

    A new timing technique for single photons based on the radio frequency phototube and optical clock or femtosecond optical frequency comb generator is proposed. The technique has a 20 ps resolution for single photons, is capable of operating with MHz frequencies and achieving 10 fs instability level.

  19. Optical properties of two-dimensional metamaterial photonic crystals

    SciTech Connect (OSTI)

    Meja-Salazar, J. R.

    2013-12-14

    In the present work, we theoretically study a 2D photonic crystal (PC) comprised by double negative (DNG) metamaterial cylinders, showing that such a system presents a superior light-matter interaction when compared with their single negative (SNG) plasmonic PC counterparts, suggesting a route to enhance the performance of sensors and photovoltaic cells. On the other hand, we have observed that depending on the frequency, the mode symmetry resembles either the case of SNG electric (SNG-E) or SNG magnetic (SNG-M) PC, suggesting that either the electric or magnetic character of the DNG metamaterial dominates in each case.

  20. Magneto-optical properties of biogenic photonic crystals in algae

    SciTech Connect (OSTI)

    Iwasaka, M.; Mizukawa, Y.

    2014-05-07

    In the present study, the effects of strong static magnetic fields on the structural colors of the cell covering crystals on a microalgae, coccolithophore, were investigated. The coccolithophore, Emiliania huxleyi, generates a precise assembly of calcite crystals called coccoliths by biomineralization. The coccoliths attached to the cells exhibited structural colors under side light illumination, and the colors underwent dynamic transitions when the magnetic fields were changed between 0?T and 5?T, probably due to diamagnetically induced changes of their inclination under the magnetic fields. The specific light-scattering property of individual coccoliths separated from the cells was also observed. Light scattering from a condensed suspension of coccoliths drastically decreased when magnetic fields of more than 4?T were applied parallel to the direction of observation. The magnetically aligned cell-covering crystals of the coccolithophores exhibited the properties of both a photonic crystal and a minimum micromirror.

  1. Nano-optical observation of cascade switching in a parallel superconducting nanowire single photon detector

    SciTech Connect (OSTI)

    Heath, Robert M. Tanner, Michael G.; Casaburi, Alessandro; Hadfield, Robert H.; Webster, Mark G.; San Emeterio Alvarez, Lara; Jiang, Weitao; Barber, Zoe H.; Warburton, Richard J.

    2014-02-10

    The device physics of parallel-wire superconducting nanowire single photon detectors is based on a cascade process. Using nano-optical techniques and a parallel wire device with spatially separate pixels, we explicitly demonstrate the single- and multi-photon triggering regimes. We develop a model for describing efficiency of a detector operating in the arm-trigger regime. We investigate the timing response of the detector when illuminating a single pixel and two pixels. We see a change in the active area of the detector between the two regimes and find the two-pixel trigger regime to have a faster timing response than the one-pixel regime.

  2. Bistable moving optical solitons in resonant photonic crystals

    SciTech Connect (OSTI)

    Vlasov, R. A.; Lemeza, A. M.

    2011-08-15

    We consider some new aspects of the formation of moving optical solitons in a medium of Bragg-type resonant grating doped with two-level atoms. For generality, account is taken of the local-field effect assisted by a sufficiently high density of resonant atoms. It is established analytically that there exists a family of soliton solutions to the two-wave Maxwell-Bloch system of equations, with these solitons exhibiting bistable properties. The existence of bistable solitons and their properties are confirmed by numerical simulations.

  3. An optical analog of the Borrmann effect in photonic crystals

    SciTech Connect (OSTI)

    Bogdanova, M. V. Lozovik, Yu. E.; Eiderman, S. L.

    2010-04-15

    Numerical simulation using the layered Korringa-Kohn-Rostoker (LKKR) method is applied to calculate the reflection and absorption spectra of an s-polarized electromagnetic wave incident on a faced-centered cubic photonic crystal (PC) with opal structure whose sites are occupied by two-layer metal-dielectric spheres. The reflection and absorption coefficients of the PC are analyzed as a function of the angle of incidence of the electromagnetic wave on the crystal surface. A range of wavelengths {lambda} and angles of inclination {theta} to the normal is found in which the absorption experiences a sharp change under small variations of the above parameters. The appearance of peaks in the absorption spectrum of the PC is analyzed, and the spectrum is compared with the behavior of the reduced density of states. By the finite difference time domain (FDTD) method applied to the Maxwell equations, the spatial distribution of the energy density of electromagnetic field inside each of five layers of the PC is obtained at angles of incidence of 23{sup o} and 30{sup o} for a wave-length of 455 nm. It is demonstrated that the sharp maxima of the density of electromagnetic-field energy that are localized on the surfaces of absorbing metal spheres correspond to the absorption maximum. At the same time, at the absorption minimum, the maxima of the field energy density in each of the five layers are localized mainly between the lattice sites of the PC. An analogy between this phenomenon and the Borrmann effect, which is known in X-ray spectroscopy of ordinary crystals, is analyzed.

  4. Enhanced-locality fiber-optic two-photon-fluorescence live-brain interrogation

    SciTech Connect (OSTI)

    Fedotov, I. V.; Doronina-Amitonova, L. V.; Sidorov-Biryukov, D. A.; Fedotov, A. B.; Anokhin, K. V.; Kilin, S. Ya.; Sakoda, K.; Zheltikov, A. M.

    2014-02-24

    Two-photon excitation is shown to substantially enhance the locality of fiber-based optical interrogation of strongly scattering biotissues. In our experiments, a high-numerical-aperture, large-core-are fiber probe is used to deliver the 200-fs output of a 100-MHz mode-locked ytterbium fiber laser to samples of live mouse brain, induce two-photon fluorescence of nitrogen–vacancy centers in diamond markers in brain sample. Fiber probes with a high numerical aperture and a large core area are shown to enable locality enhancement in fiber-laser–fiber-probe two-photon brain excitation and interrogation without sacrificing the efficiency of fluorescence response collection.

  5. Tunability of multichannel optical filter based on magnetized one-dimensional plasma photonic crystal

    SciTech Connect (OSTI)

    Jamshidi-Ghaleh, K. Karami-Garehgeshlagi, F.; Mazloom, A. A.

    2015-10-15

    A one dimensional plasma photonic crystal (1DPPC) structure was proposed to design a tunable compressing/broadening multi-channel optical filter with external controllability. The 1DPPC with arrangement of (AP){sup n}D(PA){sup n}, where A and D are the dielectric materials, P is a magnetized plasma layer and n is the number of the periodicity, was proposed. The well-known transfer matrix method was employed for analysis. In linear transmittance spectrum, n − 1 defect modes were appeared inside the photonic band gap. The results were shown that by increasing the applied magnetic field intensity and its direction, a red-shift and blue-shift were, respectively, observed in defect mode frequencies. On the other hand, the modes were compressed and broadened with increasing the intensity and the direction of the applied magnetic field, respectively. Externally controllable defect modes can be useful in designing a multichannel tunable optical filter.

  6. Optically enhanced photon recycling in mechanically stacked multijunction solar cells

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

    Steiner, Myles A.; Geisz, John F.; Ward, J. Scott; Garcia, Ivan; Friedman, Daniel J.; King, Richard R.; Chiu, Philip T.; France, Ryan M.; Duda, Anna; Olavarria, Waldo J.; et al

    2015-11-09

    Multijunction solar cells can be fabricated by mechanically bonding together component cells that are grown separately. Here, we present four-junction four-terminal mechanical stacks composed of GaInP/GaAs tandems grown on GaAs substrates and GaInAsP/GaInAs tandems grown on InP substrates. The component cells were bonded together with a low-index transparent epoxy that acts as an angularly selective reflector to the GaAs bandedge luminescence, while simultaneously transmitting nearly all of the subbandgap light. As determined by electroluminescence measurements and optical modeling, the GaAs subcell demonstrates a higher internal radiative limit and, thus, higher subcell voltage, compared with GaAs subcells without the epoxy reflector.more » The best cells demonstrate 38.8 ± 1.0% efficiency under the global spectrum at 1000 W/m2 and ~ 42% under the direct spectrum at ~100 suns. As a result, eliminating the series resistance is the key challenge for further improving the concentrator cells.« less

  7. Optically enhanced photon recycling in mechanically stacked multijunction solar cells

    SciTech Connect (OSTI)

    Steiner, Myles A.; Geisz, John F.; Ward, J. Scott; Garcia, Ivan; Friedman, Daniel J.; King, Richard R.; Chiu, Philip T.; France, Ryan M.; Duda, Anna; Olavarria, Waldo J.; Young, Michelle; Kurtz, Sarah R.

    2015-11-09

    Multijunction solar cells can be fabricated by mechanically bonding together component cells that are grown separately. Here, we present four-junction four-terminal mechanical stacks composed of GaInP/GaAs tandems grown on GaAs substrates and GaInAsP/GaInAs tandems grown on InP substrates. The component cells were bonded together with a low-index transparent epoxy that acts as an angularly selective reflector to the GaAs bandedge luminescence, while simultaneously transmitting nearly all of the subbandgap light. As determined by electroluminescence measurements and optical modeling, the GaAs subcell demonstrates a higher internal radiative limit and, thus, higher subcell voltage, compared with GaAs subcells without the epoxy reflector. The best cells demonstrate 38.8 ± 1.0% efficiency under the global spectrum at 1000 W/m2 and ~ 42% under the direct spectrum at ~100 suns. As a result, eliminating the series resistance is the key challenge for further improving the concentrator cells.

  8. High optical efficiency and photon noise limited sensitivity of microwave kinetic inductance detectors using phase readout

    SciTech Connect (OSTI)

    Janssen, R. M. J. Endo, A.; Baselmans, J. J. A.; Ferrari, L.; Yates, S. J. C.; Baryshev, A. M.; Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen ; Klapwijk, T. M.; Physics Department, Moscow State Pedagogical University, Moscow 119991

    2013-11-11

    We demonstrate photon noise limited performance in both phase and amplitude readout in microwave kinetic inductance detectors (MKIDs) consisting of NbTiN and Al, down to 100 fW of optical power. We simulate the far field beam pattern of the lens-antenna system used to couple radiation into the MKID and derive an aperture efficiency of 75%. This is close to the theoretical maximum of 80% for a single-moded detector. The beam patterns are verified by a detailed analysis of the optical coupling within our measurement setup.

  9. Channel-capacity gain in entanglement-assisted communication protocols based exclusively on linear optics, single-photon inputs, and coincidence photon counting

    SciTech Connect (OSTI)

    Lougovski, P.; Uskov, D. B.

    2015-08-04

    Entanglement can effectively increase communication channel capacity as evidenced by dense coding that predicts a capacity gain of 1 bit when compared to entanglement-free protocols. However, dense coding relies on Bell states and when implemented using photons the capacity gain is bounded by 0.585 bits due to one's inability to discriminate between the four optically encoded Bell states. In this research we study the following question: Are there alternative entanglement-assisted protocols that rely only on linear optics, coincidence photon counting, and separable single-photon input states and at the same time provide a greater capacity gain than 0.585 bits? In this study, we show that besides the Bell states there is a class of bipartite four-mode two-photon entangled states that facilitate an increase in channel capacity. We also discuss how the proposed scheme can be generalized to the case of two-photon N-mode entangled states for N=6,8.

  10. Channel-capacity gain in entanglement-assisted communication protocols based exclusively on linear optics, single-photon inputs, and coincidence photon counting

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

    Lougovski, P.; Uskov, D. B.

    2015-08-04

    Entanglement can effectively increase communication channel capacity as evidenced by dense coding that predicts a capacity gain of 1 bit when compared to entanglement-free protocols. However, dense coding relies on Bell states and when implemented using photons the capacity gain is bounded by 0.585 bits due to one's inability to discriminate between the four optically encoded Bell states. In this research we study the following question: Are there alternative entanglement-assisted protocols that rely only on linear optics, coincidence photon counting, and separable single-photon input states and at the same time provide a greater capacity gain than 0.585 bits? In thismore » study, we show that besides the Bell states there is a class of bipartite four-mode two-photon entangled states that facilitate an increase in channel capacity. We also discuss how the proposed scheme can be generalized to the case of two-photon N-mode entangled states for N=6,8.« less

  11. Elastic photon scattering from sup 4 He in the. Delta. (1232) region

    SciTech Connect (OSTI)

    Austin, E.J.

    1988-01-01

    We have measured the differential cross section at laboratory angles 24{degree}, 30{degree}, 45{degree}, and 60{degree} for the reaction {sup 4}He({gamma},{gamma}){sup 4}He at an average lab energy of 320 MeV. This work was performed at the MIT Bates Linear Accelerator using a bremsstrahlung photon beam produced by a 330 MeV electron beam. The scattered photons were detected with a new, high resolution (1.68% FWHM at 330 MeV) NaI(Tl) total absorption scintillation counter. The data were summed over a nine MeV interval below the endpoint of the elastically scattered photon spectrum. Cosmic ray background was rejected by a plastic scintillator veto shield that surrounded the detector and the energy resolution was sufficient to exclude photons from {pi}{sup 0} decay and inelastic scattering from the region of interest. The results were compared with the predictions of the {Delta}-hole calculations of Koch, Moniz, and Ohtsuka and were found to be in excellent agreement. This measurement is the first unambiguous test of the {Delta}-hole formalism for this reaction near the peak of the {Delta} resonance.

  12. Soft-Lithographical Fabrication of Three-dimensional Photonic Crystals in the Optical Regime

    SciTech Connect (OSTI)

    Jae-Hwang Lee

    2006-08-09

    detailed microscopy of the structure, we show that the diffracted moire fringe can be used as a nondestructive tool to analyze the alignment of multilayered structures. We demonstrate the alignment method for the case of layer-by-layer microstructures using soft lithography. The alignment method yields high contrast of fringes even when the materials being aligned have very weak contrasts. The imaging method of diffracted moire fringes is a versatile visual tool for the microfabrication of transparent deformable microstructures in layer-by-layer fashion. Third, we developed several methods to convert a polymer template to dielectric or metallic structures, for instance, metallic infiltration using electrodeposition, metallic coating using sputter deposition, dielectric infiltration using titania nano-slurry, and dielectric coating using atomic layer deposition of Titania. By several different developed techniques, high quality photonic crystals have been successfully fabricated; however, I will focus on a line of techniques to reach metallic photonic crystals in this dissertation since they are completely characterized at this moment. In addition to the attempts for photonic crystal fabrication, our non-photolithographic technique is applied for other photonic applications such as small optical waveguides whose diameter is comparable to the wavelength of guided light. Although, as guiding medium, polymers have tremendous potential because of their enormous variation in optical, chemical and mechanical properties, their application for optical waveguides is limited in conventional photolithography. By 2P-{mu}TM, we achieve low cost, high yield, high fidelity, and tailorable fabrication of small waveguides. Embedded semiconductor quantum-dots and grating couplers are used for efficient internal and external light source, respectively.

  13. Three-dimensional photonic crystal fluorinated tin oxide (FTO) electrodes : synthesis and optical and electrical properties.

    SciTech Connect (OSTI)

    Yang, Z.; Gao, S.; Li, W.; Vlasko-Vlasov, V.; Welp, U.; Kwok, W.-K.; Xu, T.

    2011-04-01

    Photovoltaic (PV) schemes often encounter a pair of fundamentally opposing requirements on the thickness of semiconductor layer: a thicker PV semiconductor layer provides enhanced optical density, but inevitably increases the charge transport path length. An effective approach to solve this dilemma is to enhance the interface area between the terminal electrode, i.e., transparent conducting oxide (TCO) and the semiconductor layer. As such, we report a facile, template-assisted, and solution chemistry-based synthesis of 3-dimensional inverse opal fluorinated tin oxide (IO-FTO) electrodes. Synergistically, the photonic crystal structure possessed in the IO-FTO exhibits strong light trapping capability. Furthermore, the electrical properties of the IO-FTO electrodes are studied by Hall effect and sheet resistance measurement. Using atomic layer deposition method, an ultrathin TiO{sub 2} layer is coated on all surfaces of the IO-FTO electrodes. Cyclic voltammetry study indicates that the resulting TiO{sub 2}-coated IO-FTO shows excellent potentials as electrodes for electrolyte-based photoelectrochemical solar cells.

  14. Multi-Region Surface Plasmon Resonance Fiber-Optic Sensors for...

    Office of Scientific and Technical Information (OSTI)

    Sensors for Monitoring High-Consequence Systems. Citation Details In-Document Search Title: Multi-Region Surface Plasmon Resonance Fiber-Optic Sensors for Monitoring ...

  15. Observation of nonlinear bands in near-field scanning optical microscopy of a photonic-crystal waveguide

    SciTech Connect (OSTI)

    Singh, A.; Huisman, S. R.; Ctistis, G. Mosk, A. P.; Pinkse, P. W. H.; Korterik, J. P.; Herek, J. L.

    2015-01-21

    We have measured the photonic bandstructure of GaAs photonic-crystal waveguides with high resolution in energy as well as in momentum using near-field scanning optical microscopy. Intriguingly, we observe additional bands that are not predicted by eigenmode solvers, as was recently demonstrated by Huisman et al. [Phys. Rev. B 86, 155154 (2012)]. We study the presence of these additional bands by performing measurements of these bands while varying the incident light power, revealing a non-linear power dependence. Here, we demonstrate experimentally and theoretically that the observed additional bands are caused by a waveguide-specific near-field tip effect not previously reported, which can significantly phase-modulate the detected field.

  16. Non-degenerate two-photon absorption

    Office of Scientific and Technical Information (OSTI)

    Optical Systems (CUDOS), Institute of Photonics and Optical Science, School of Physics, ... and B. J. Eggleton, "Nonlinear silicon photonics analyzed with the moment method," J. Opt. ...

  17. Photonic Systems | The Ames Laboratory

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

    Photonic Systems Photonic Systems Ames Laboratory physicists were the first to design and demonstrate the existence of photonic band gap crystals, a discovery that led to the development of the rapidly expanding field of photonic crystals. Photonic crystals are expected to have revolutionary applications in optical communication and other areas of light technology. Image Photonic Cube For additional information on Photonic Systems, please visit https://www.ameslab.gov/dmse/fwp/photonic-s

  18. Photonic-powered cable assembly

    DOE Patents [OSTI]

    Sanderson, Stephen N.; Appel, Titus James; Wrye, IV, Walter C.

    2013-01-22

    A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.

  19. Photonic-powered cable assembly

    DOE Patents [OSTI]

    Sanderson, Stephen N; Appel, Titus James; Wrye, IV, Walter C

    2014-06-24

    A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.

  20. Optical properties of GaAs 2D hexagonal and cubic photonic crystal

    SciTech Connect (OSTI)

    Arab, F. Assali, A.; Grain, R.; Kanouni, F.

    2015-03-30

    In this paper we present our theoretical study of 2D hexagonal and cubic rods GaAs in air, with plan wave expansion (PWE) and finite difference time domain (FDTD) by using BandSOLVE and FullWAVE of Rsoft photonic CAD package. In order to investigate the effect of symmetry and radius, we performed calculations of the band structures for both TM and TE polarization, contour and electromagnetic propagation and transmission spectra. Our calculations show that the hexagonal structure gives a largest band gaps compare to cubic one for a same filling factor.

  1. Photonic Power Delivery Through Optical Fiber Using Very High Power Laser Diode Arrays

    SciTech Connect (OSTI)

    Heino, Matthew; Saethre, Robert

    1999-05-01

    Described is a system that will provide isolated electric power for a circuit that drives the core reset of a pulsed power modulator. This can be accomplished by coupling light from a number of diode laser bars to bundles of 200 um multimode optical fibers. This is then coupled to photo-voltaic power converters that will deliver 16 V 29mA of electricity from 1 watt of optical power. Spot size at the bundle face is a Gausian ellipse with a major axis of 1.4 mm radius and a minor axis of four bundles of 12 fibers generating a total of 24 W of electrical power. Various schemes are used to maximize coupling into the optical filber while limiting the number of optical components, and comparing components such as fresnel and aspheric lenses and lens ducts for effectiveness and cost. This will provide a completely isolated low power source for high voltage, high current environments where tradional isolation techniques yield inadequate isolation or prove too cumbersome.

  2. Nonlinear optical response of semiconductor-nanocrystals-embedded photonic band gap structure

    SciTech Connect (OSTI)

    Liao, Chen; Zhang, Huichao; Tang, Luping; Zhou, Zhiqiang; Lv, Changgui; Cui, Yiping; Zhang, Jiayu

    2014-04-28

    Colloidal CdSe/ZnS core/shell nanocrystals (NCs), which were dispersed in SiO{sub 2} sol, were utilized to fabricate a SiO{sub 2}:NCs/TiO{sub 2} all-dielectric photonic band gap (PBG) structure. The third-order nonlinear refractive index (n{sub 2}) of the PBG structure was nearly triple of that of the SiO{sub 2}:NCs film due to the local field enhancement in the PBG structure. The photoinduced change in refractive index (Δn) could shift the PBG band edge, so the PBG structure would show significant transmission modification, whose transmission change was ∼17 folds of that of the SiO{sub 2}:NCs film. Under excitation of a 30 GW/cm{sup 2} femtosecond laser beam, a transmission decrease of 80% was realized.

  3. Thermo-optically tuned photonic resonators with concurrent electrical connection and thermal isolation

    DOE Patents [OSTI]

    Lentine, Anthony L.; Kekatpure, Rohan Deodatta; Zortman, William A.; Savignon, Daniel J.

    2016-06-14

    A photonic resonator system is designed to use thermal tuning to adjust the resonant wavelength of each resonator in the system, with a separate tuning circuit associated with each resonator so that individual adjustments may be made. The common electrical ground connection between the tuning circuits is particularly formed to provide thermal isolation between adjacent resonators by including a capacitor along each return path to ground, where the presence of the capacitor's dielectric material provides the thermal isolation. The use of capacitively coupling necessarily requires the use of an AC current as an input to the heater element (conductor/resistor) of each resonator, where the RMS value of the AC signal is indicative of the amount of heat that is generated along the element and the degree of wavelength tuning that is obtained.

  4. A possibility for using an APPLE undulator to generate a photon beam with transverse optical modes.

    SciTech Connect (OSTI)

    Sasaki, S.; McNulty, I.; Shimada, T.; JAEA

    2008-01-01

    We investigate use of an APPLE-type undulator for generating Laguerre-Gaussian (LG) and Hermite-Gaussian (HG) mode beams. We find that the second harmonic radiation in the circular mode corresponds to an LG beam with l=1, and the second harmonic in the linear mode corresponds to an HG beam with l=1. The combination of an APPLE undulator and conventional monochromator optics may provide an opportunity for a new type of experimental research in the synchrotron radiation community.

  5. Photonic crystal light source

    DOE Patents [OSTI]

    Fleming, James G.; Lin, Shawn-Yu; Bur, James A.

    2004-07-27

    A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

  6. Observations of regional and local variability in the optical properties of maritime clouds

    SciTech Connect (OSTI)

    White, A.B.

    1996-04-01

    White and Fairall (1995) calculated the optical properties of the marine boundary layer (MBL) clouds observed during the Atlantic Stratocumulus Transition Experiment (ASTEX) and compared their results with the results obtained by Fairall et al. for the MBL clouds observed during the First International Satellite Climatology Program (ISSCP) Regional Experiment (FIRE). They found a factor of two difference in the optical depth versus liquid water relationship that applies to the clouds observed in each case. In the present study, we present evidence to support this difference. We also investigate the local variability exhibited in the ASTEX optical properties using measurements of the boundary layer aerosol concentration.

  7. NIF & Photon Science Management

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

    management NIF & Photon Science Management The management team for the NIF & Photon Science Principal Directorate supports the directorate's key mission areas: Stockpile Stewardship, national security applications, NIF Discovery Science, laser-based directed energy and related laser and optical technologies, and advanced photon technologies. Directorate Programs Jeff Wisoff Principal Associate Director NIF & Photon Science Jeff Atherton Principal Deputy Principal Associate Director

  8. Nanowires and nanoribbons as subwavelength optical waveguides and their use as components in photonic circuits and devices

    DOE Patents [OSTI]

    Yang, Peidong; Law, Matt; Sirbuly, Donald J.; Johnson, Justin C.; Saykally, Richard; Fan, Rong; Tao, Andrea

    2012-10-02

    Nanoribbons and nanowires having diameters less than the wavelength of light are used in the formation and operation of optical circuits and devices. Such nanostructures function as subwavelength optical waveguides which form a fundamental building block for optical integration. The extraordinary length, flexibility and strength of these structures enable their manipulation on surfaces, including the precise positioning and optical linking of nanoribbon/wire waveguides and other nanoribbon/wire elements to form optical networks and devices. In addition, such structures provide for waveguiding in liquids, enabling them to further be used in other applications such as optical probes and sensors.

  9. Photonic layered media

    DOE Patents [OSTI]

    Fleming, James G.; Lin, Shawn-Yu

    2002-01-01

    A new class of structured dielectric media which exhibit significant photonic bandstructure has been invented. The new structures, called photonic layered media, are easy to fabricate using existing layer-by-layer growth techniques, and offer the ability to significantly extend our practical ability to tailor the properties of such optical materials.

  10. Photon-photon collisions

    SciTech Connect (OSTI)

    Burke, D.L.

    1982-10-01

    Studies of photon-photon collisions are reviewed with particular emphasis on new results reported to this conference. These include results on light meson spectroscopy and deep inelastic e..gamma.. scattering. Considerable work has now been accumulated on resonance production by ..gamma gamma.. collisions. Preliminary high statistics studies of the photon structure function F/sub 2//sup ..gamma../(x,Q/sup 2/) are given and comments are made on the problems that remain to be solved.

  11. Optical Society of America (OSA) Fellows

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

    in optics and photonics. Since 1916, OSA has worked to bring together scientists, engineers, educators, technicians and business leaders in the fields of optics and photonics. ...

  12. Challenges in the implementation of dense wavelength division multiplexed (DWDM) optical interconnects using resonant silicon photonics (invited)

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

    Lentine, Anthony L.; DeRose, Christopher T.

    2016-02-12

    In this study, small silicon photonics micro-resonator modulators and filters hold the promise for multi-terabit per-second interconnects at energy consumptions well below 1 pJ/bit. To date, no products exist and little known commercial development is occurring using this technology. Why? In this talk, we review the many challenges that remain to be overcome in bringing this technology from the research labs to the field where they can overcome important commercial, industrial, and national security limitations of existing photonic technologies.

  13. Optical cone beam tomography of Cherenkov-mediated signals for fast 3D dosimetry of x-ray photon beams in water

    SciTech Connect (OSTI)

    Glaser, Adam K. E-mail: Brian.W.Pogue@dartmouth.edu; Andreozzi, Jacqueline M.; Zhang, Rongxiao; Pogue, Brian W. E-mail: Brian.W.Pogue@dartmouth.edu; Gladstone, David J.

    2015-07-15

    Purpose: To test the use of a three-dimensional (3D) optical cone beam computed tomography reconstruction algorithm, for estimation of the imparted 3D dose distribution from megavoltage photon beams in a water tank for quality assurance, by imaging the induced Cherenkov-excited fluorescence (CEF). Methods: An intensified charge-coupled device coupled to a standard nontelecentric camera lens was used to tomographically acquire two-dimensional (2D) projection images of CEF from a complex multileaf collimator (MLC) shaped 6 MV linear accelerator x-ray photon beam operating at a dose rate of 600 MU/min. The resulting projections were used to reconstruct the 3D CEF light distribution, a potential surrogate of imparted dose, using a Feldkamp–Davis–Kress cone beam back reconstruction algorithm. Finally, the reconstructed light distributions were compared to the expected dose values from one-dimensional diode scans, 2D film measurements, and the 3D distribution generated from the clinical Varian ECLIPSE treatment planning system using a gamma index analysis. A Monte Carlo derived correction was applied to the Cherenkov reconstructions to account for beam hardening artifacts. Results: 3D light volumes were successfully reconstructed over a 400 × 400 × 350 mm{sup 3} volume at a resolution of 1 mm. The Cherenkov reconstructions showed agreement with all comparative methods and were also able to recover both inter- and intra-MLC leaf leakage. Based upon a 3%/3 mm criterion, the experimental Cherenkov light measurements showed an 83%–99% pass fraction depending on the chosen threshold dose. Conclusions: The results from this study demonstrate the use of optical cone beam computed tomography using CEF for the profiling of the imparted dose distribution from large area megavoltage photon beams in water.

  14. Photon-photon collisions

    SciTech Connect (OSTI)

    Brodsky, S.J.

    1988-07-01

    Highlights of the VIIIth International Workshop on Photon-Photon Collisions are reviewed. New experimental and theoretical results were reported in virtually every area of ..gamma gamma.. physics, particularly in exotic resonance production and tests of quantum chromodynamics where asymptotic freedom and factorization theorems provide predictions for both inclusive and exclusive ..gamma gamma.. reactions at high momentum transfer. 73 refs., 12 figs.

  15. Sandia National Laboratories: RF & Photonics

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

    RF & Photonics Sensors Sandia provides photonics technology based solutions (science, technology, microsystems, subsystems, prototyping and low volume production) for National Security customers Custom Solutions Optics Optical MEMS Sandia designs, develops, builds and delivers highly sensitive, reliable micro- and nano-scale optical solutions across electromechanical and biological domains for physical sensing and optical signal processing in national security applications. Sandia uses

  16. Wave like signatures in aerosol optical depth and associated radiative impacts over the central Himalayan region

    SciTech Connect (OSTI)

    Shukla, K. K.; Phanikumar, D. V.; Kumar, Niranjan; Reddy, Kishore; Kotamarthi, Veerabhadra R.; Newsom, Rob K.; Ouarda, Taha B.

    2015-10-01

    In this study, we present a case study on 16 October 2011 to show the first observational evidence of the influence of short period gravity waves in aerosol transport during daytime over the central Himalayan region. The Doppler lidar data has been utilized to address the daytime boundary layer evolution and related aerosol dynamics over the site. Mixing layer height is estimated by wavelet covariance transform method and found to be ~ 0.7 km, AGL. Aerosol optical depth observations during daytime revealed an asymmetry showing clear enhancement during afternoon hours as compared to forenoon. Interestingly, Fourier and wavelet analysis of vertical velocity and attenuated backscatter showed similar 50-90 min short period gravity wave signatures during afternoon hours. Moreover, our observations showed that gravity waves are dominant within the boundary layer implying that the daytime boundary layer dynamics is playing a vital role in transporting the aerosols from surface to the top of the boundary layer. Similar modulations are also evident in surface parameters like temperature, relative humidity and wind speed indicating these waves are associated with the dynamical aspects over Himalayan region. Finally, time evolution of range-23 height indicator snapshots during daytime showed strong upward velocities especially during afternoon hours implying that convective processes through short period gravity waves plays a significant role in transporting aerosols from the nearby valley region to boundary layer top over the site. These observations also establish the importance of wave induced daytime convective boundary layer dynamics in the lower Himalayan region.

  17. Soliton delivery of few-cycle optical gigawatt pulses in Kagome-lattice hollow-core photonic crystal fibers

    SciTech Connect (OSTI)

    Im, Song-Jin; Husakou, Anton; Herrmann, Joachim

    2010-08-15

    We study the delivery of few-cycle soliton-like pulses at 800 nm with gigawatt power or microjoule energy through a hollow-core kagome-lattice photonic crystal fiber over 1 m with preserved temporal and spectral shape. We show that with optimized pressure of the argon filling, 5 fs input pulses are compressed up to 2.5 fs after 20 cm and restore their shape after 1 m propagation.

  18. Charging a Battery-Powered Device with a Fiber-Optically Connected Photonic Power System for Achieving High-Voltage Isolation

    SciTech Connect (OSTI)

    Lizon, David C; Gioria, Jack G; Dale, Gregory E; Snyder, Hans R

    2008-01-01

    This paper describes the development and testing of a system to provide isolated power to the cathode-subsystem electronics of an x-ray tube. These components are located at the cathode potential of several hundred kilovolts, requiring a supply of power isolated from this high voltage. In this design a fiber-optically connected photonic power system (PPS) is used to recharge a lithium-ion battery pack, which will subsequently supply power to the cathode-subsystem electronics. The suitability of the commercially available JDSU PPS for this application is evaluated. The output of the ppe converter is characterized. The technical aspects of its use for charging a variety of Li-Ion batteries are discussed. Battery charge protection requirements and safety concerns are also addressed.

  19. Two Photon Distribution Amplitudes

    SciTech Connect (OSTI)

    El Beiyad, M.; Pire, B.; Szymanowski, L.; Wallon, S.

    2008-08-29

    The factorization of the amplitude of the process {gamma}*{gamma}{yields}{gamma}{gamma} in the low energy and high photon virtuality region is demonstrated at the Born order and in the leading logarithmic approximation. The leading order two photon (generalized) distribution amplitudes exhibit a characteristic ln Q{sup 2} behaviour and obey new inhomogeneous evolution equations.

  20. Photon-photon collisions

    SciTech Connect (OSTI)

    Brodsky, S.J.

    1985-01-01

    The study of photon-photon collisions has progressed enormously, stimulated by new data and new calculational tools for QCD. In the future we can expect precise determinations of ..cap alpha../sub s/ and ..lambda../sup ms/ from the ..gamma..*..gamma.. ..-->.. ..pi../sup 0/ form factor and the photon structure function, as well as detailed checks of QCD, determination of the shape of the hadron distribution amplitudes from ..gamma gamma.. ..-->.. H anti H, reconstruction of sigma/sub ..gamma gamma../ from exclusive channels at low W/sub ..gamma gamma../, definitive studies of high p/sub T/ hadron and jet production, and studies of threshold production of charmed systems. Photon-photon collisions, along with radiative decays of the psi and UPSILON, are ideal for the study of multiquark and gluonic resonances. We have emphasized the potential for resonance formation near threshold in virtually every hadronic exclusive channel, including heavy quark states c anti c c anti c, c anti c u anti u, etc. At higher energies SLC, LEP, ...) parity-violating electroweak effects and Higgs production due to equivalent Z/sup 0/ and W/sup + -/ beams from e ..-->.. eZ/sup 0/ and e ..-->.. nu W will become important. 44 references.

  1. Ion photon emission microscope

    DOE Patents [OSTI]

    Doyle, Barney L.

    2003-04-22

    An ion beam analysis system that creates microscopic multidimensional image maps of the effects of high energy ions from an unfocussed source upon a sample by correlating the exact entry point of an ion into a sample by projection imaging of the ion-induced photons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted photons are collected in the lens system of a conventional optical microscope, and projected on the image plane of a high resolution single photon position sensitive detector. Position signals from this photon detector are then correlated in time with electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these photons initially.

  2. Knot Undulator to Generate Linearly Polarized Photons with Low...

    Office of Scientific and Technical Information (OSTI)

    Heat load on beamline optics is a serious problem to generate pure linearly polarized ... Language: English Subject: 43 PARTICLE ACCELERATORS; OPTICS; PERMANENT MAGNETS; PHOTONS; ...

  3. Optical photon transport in powdered-phosphor scintillators. Part II. Calculation of single-scattering transport parameters

    SciTech Connect (OSTI)

    Poludniowski, Gavin G.; Evans, Philip M.

    2013-04-15

    Purpose: Monte Carlo methods based on the Boltzmann transport equation (BTE) have previously been used to model light transport in powdered-phosphor scintillator screens. Physically motivated guesses or, alternatively, the complexities of Mie theory have been used by some authors to provide the necessary inputs of transport parameters. The purpose of Part II of this work is to: (i) validate predictions of modulation transform function (MTF) using the BTE and calculated values of transport parameters, against experimental data published for two Gd{sub 2}O{sub 2}S:Tb screens; (ii) investigate the impact of size-distribution and emission spectrum on Mie predictions of transport parameters; (iii) suggest simpler and novel geometrical optics-based models for these parameters and compare to the predictions of Mie theory. A computer code package called phsphr is made available that allows the MTF predictions for the screens modeled to be reproduced and novel screens to be simulated. Methods: The transport parameters of interest are the scattering efficiency (Q{sub sct}), absorption efficiency (Q{sub abs}), and the scatter anisotropy (g). Calculations of these parameters are made using the analytic method of Mie theory, for spherical grains of radii 0.1-5.0 {mu}m. The sensitivity of the transport parameters to emission wavelength is investigated using an emission spectrum representative of that of Gd{sub 2}O{sub 2}S:Tb. The impact of a grain-size distribution in the screen on the parameters is investigated using a Gaussian size-distribution ({sigma}= 1%, 5%, or 10% of mean radius). Two simple and novel alternative models to Mie theory are suggested: a geometrical optics and diffraction model (GODM) and an extension of this (GODM+). Comparisons to measured MTF are made for two commercial screens: Lanex Fast Back and Lanex Fast Front (Eastman Kodak Company, Inc.). Results: The Mie theory predictions of transport parameters were shown to be highly sensitive to both grain size

  4. Silicon photonic heater-modulator

    DOE Patents [OSTI]

    Zortman, William A.; Trotter, Douglas Chandler; Watts, Michael R.

    2015-07-14

    Photonic modulators, methods of forming photonic modulators and methods of modulating an input optical signal are provided. A photonic modulator includes a disk resonator having a central axis extending along a thickness direction of the disk resonator. The disk resonator includes a modulator portion and a heater portion. The modulator portion extends in an arc around the central axis. A PN junction of the modulator portion is substantially normal to the central axis.

  5. Photon-in photon-out hard X-ray spectroscopy at the Linac Coherent...

    Office of Scientific and Technical Information (OSTI)

    different source characteristics and its resulting impact on sample delivery, X-ray optics, X-ray detection and data acquisition. Here it is described how photon-in photon-out...

  6. Methods and apparatus for cleaning objects in a chamber of an optical instrument by generating reactive ions using photon radiation

    SciTech Connect (OSTI)

    Klebanoff, Leonard E.; Delgado, Gildardo R.; Hollenshead, Jeromy T.; Umstadter, Karl R.; Starodub, Elena; Zhuang, Guorong V.

    2015-10-13

    An optical instrument, including a chamber, an object exposed to an interior of the chamber, a source of low-pressure gas, the gas comprising at least one of low-pressure molecular hydrogen gas, low-pressure molecular oxygen and a low-pressure noble gas, the source of low pressure gas being fluidly coupled to the chamber, a low voltage source electrically coupled between the object and a remaining portion of the instrument that is exposed to the interior of the chamber so as to maintain the object at a low voltage relative to the remaining portion, and an EUV/VUV light source adapted to direct EUV/VUV light through the low pressure gas in the chamber onto the object. In such a system, when the EUV/VUV light source is activated ions of the low-pressure gas are formed and directed to the object. The ions may be ions of Hydrogen, Oxygen or a noble gas.

  7. Modules and methods for all photonic computing

    DOE Patents [OSTI]

    Schultz, David R.; Ma, Chao Hung

    2001-01-01

    A method for all photonic computing, comprising the steps of: encoding a first optical/electro-optical element with a two dimensional mathematical function representing input data; illuminating the first optical/electro-optical element with a collimated beam of light; illuminating a second optical/electro-optical element with light from the first optical/electro-optical element, the second optical/electro-optical element having a characteristic response corresponding to an iterative algorithm useful for solving a partial differential equation; iteratively recirculating the signal through the second optical/electro-optical element with light from the second optical/electro-optical element for a predetermined number of iterations; and, after the predetermined number of iterations, optically and/or electro-optically collecting output data representing an iterative optical solution from the second optical/electro-optical element.

  8. Apparatus and method for qualitative and quantitative measurements of optical properties of turbid media using frequency-domain photon migration

    DOE Patents [OSTI]

    Tromberg, B.J.; Tsay, T.T.; Berns, M.W.; Svaasand, L.O.; Haskell, R.C.

    1995-06-13

    Optical measurements of turbid media, that is media characterized by multiple light scattering, is provided through an apparatus and method for exposing a sample to a modulated laser beam. The light beam is modulated at a fundamental frequency and at a plurality of integer harmonics thereof. Modulated light is returned from the sample and preferentially detected at cross frequencies at frequencies slightly higher than the fundamental frequency and at integer harmonics of the same. The received radiance at the beat or cross frequencies is compared against a reference signal to provide a measure of the phase lag of the radiance and modulation ratio relative to a reference beam. The phase and modulation amplitude are then provided as a frequency spectrum by an array processor to which a computer applies a complete curve fit in the case of highly scattering samples or a linear curve fit below a predetermined frequency in the case of highly absorptive samples. The curve fit in any case is determined by the absorption and scattering coefficients together with a concentration of the active substance in the sample. Therefore, the curve fitting to the frequency spectrum can be used both for qualitative and quantitative analysis of substances in the sample even though the sample is highly turbid. 14 figs.

  9. Apparatus and method for qualitative and quantitative measurements of optical properties of turbid media using frequency-domain photon migration

    DOE Patents [OSTI]

    Tromberg, Bruce J.; Tsay, Tsong T.; Berns, Michael W.; Svaasand, Lara O.; Haskell, Richard C.

    1995-01-01

    Optical measurements of turbid media, that is media characterized by multiple light scattering, is provided through an apparatus and method for exposing a sample to a modulated laser beam. The light beam is modulated at a fundamental frequency and at a plurality of integer harmonics thereof. Modulated light is returned from the sample and preferentially detected at cross frequencies at frequencies slightly higher than the fundamental frequency and at integer harmonics of the same. The received radiance at the beat or cross frequencies is compared against a reference signal to provide a measure of the phase lag of the radiance and modulation ratio relative to a reference beam. The phase and modulation amplitude are then provided as a frequency spectrum by an array processor to which a computer applies a complete curve fit in the case of highly scattering samples or a linear curve fit below a predetermined frequency in the case of highly absorptive samples. The curve fit in any case is determined by the absorption and scattering coefficients together with a concentration of the active substance in the sample. Therefore, the curve fitting to the frequency spectrum can be used both for qualitative and quantitative analysis of substances in the sample even though the sample is highly turbid.

  10. Electrically pumped edge-emitting photonic bandgap semiconductor laser

    DOE Patents [OSTI]

    Lin, Shawn-Yu; Zubrzycki, Walter J.

    2004-01-06

    A highly efficient, electrically pumped edge-emitting semiconductor laser based on a one- or two-dimensional photonic bandgap (PBG) structure is described. The laser optical cavity is formed using a pair of PBG mirrors operating in the photonic band gap regime. Transverse confinement is achieved by surrounding an active semiconductor layer of high refractive index with lower-index cladding layers. The cladding layers can be electrically insulating in the passive PBG mirror and waveguide regions with a small conducting aperture for efficient channeling of the injection pump current into the active region. The active layer can comprise a quantum well structure. The quantum well structure can be relaxed in the passive regions to provide efficient extraction of laser light from the active region.

  11. Optical emission from a small scale model electric arc furnace in 250-600 nm region

    SciTech Connect (OSTI)

    Maekinen, A.; Tikkala, H.; Aksela, H.; Niskanen, J.

    2013-04-15

    Optical emission spectroscopy has been for long proposed for monitoring and studying industrial steel making processes. Whereas the radiative decay of thermal excitations is always taking place in high temperatures needed in steel production, one of the most promising environment for such studies are electric arc furnaces, creating plasma in excited electronic states that relax with intense characteristic emission in the optical regime. Unfortunately, large industrial scale electric arc furnaces also present a challenging environment for optical emission studies and application of the method is not straightforward. To study the usability of optical emission spectroscopy in real electric arc furnaces, we have developed a laboratory scale DC electric arc furnace presented in this paper. With the setup, optical emission spectra of Fe, Cr, Cr{sub 2}O{sub 3}, Ni, SiO{sub 2}, Al{sub 2}O{sub 3}, CaO, and MgO were recorded in the wavelength range 250-600 nm and the results were analyzed with the help of reference data. The work demonstrates that using characteristic optical emission, obtaining in situ chemical information from oscillating plasma of electric arc furnaces is indeed possible. In spite of complications, the method could possibly be applied to industrial scale steel making process in order to improve its efficiency.

  12. Designing of Metallic Photonic Structures and Applications

    SciTech Connect (OSTI)

    Yong-Sung Kim

    2006-08-09

    In this thesis our main interest has been to investigate metallic photonic crystal and its applications. We explained how to solve a periodic photonic structure with transfer matrix method and when and how to use modal expansion method. Two different coating methods were introduced, modifying a photonic structure's intrinsic optical properties and rigorous calculation results are presented. Two applications of metallic photonic structures are introduced. For thermal emitter, we showed how to design and find optimal structure. For conversion efficiency increasing filter, we calculated its efficiency and the way to design it. We presented the relation between emitting light spectrum and absorption and showed the material and structural dependency of the absorption spectrum. By choosing a proper base material and structural parameters, we can design a selective emitter at a certain region we are interested in. We have developed a theoretical model to analyze a blackbody filament enclosed by a metallic mesh which can increase the efficiency of converting a blackbody radiation to visible light. With this model we found that a square lattice metallic mesh enclosing a filament might increase the efficiency of incandescent lighting sources. Filling fraction and thickness dependency were examined and presented. Combining these two parameters is essential to achieve the maximum output result.

  13. Properties of polycyclic aromatic hydrocarbons in the northwest photon dominated region of NGC 7023. II. Traditional PAH analysis using k-means as a visualization tool

    SciTech Connect (OSTI)

    Boersma, C.; Bregman, J.; Allamandola, L. J.

    2014-11-10

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer-IRS spectral map of the northwest photon dominated region (PDR) in NGC 7023 is analyzed using the 'traditional' approach in which the PAH bands and plateaus between 5.2-19.5 μm are isolated by subtracting the underlying continuum and removing H{sub 2} emission lines. The spectra are organized into seven spectroscopic bins by using k-means clustering. Each cluster corresponds to, and reveals, a morphological zone within NGC 7023. The zones self-organize parallel to the well-defined PDR front that coincides with an increase in intensity of the H{sub 2} emission lines. PAH band profiles and integrated strengths are measured, classified, and mapped. The morphological zones revealed by the k-means clustering provides deeper insight into the conditions that drive variations in band strength ratios and evolution of the PAH population that otherwise would be lost. For example, certain band-band relations are bifurcated, revealing two limiting cases; one associated with the PDR, the other with the diffuse medium. Traditionally, PAH band strength ratios are used to gain insight into the properties of the emitting PAH population, i.e., charge, size, structure, and composition. Insights inferred from this work are compared and contrasted to those from Boersma et al. (first paper in this series), where the PAH emission in NGC 7023 is decomposed exclusively using the PAH spectra and tools made available through the NASA Ames PAH IR Spectroscopic Database.

  14. Memory effect in silicon time-gated single-photon avalanche diodes

    SciTech Connect (OSTI)

    Dalla Mora, A.; Contini, D. Di Sieno, L.; Tosi, A.; Boso, G.; Villa, F.; Pifferi, A.

    2015-03-21

    We present a comprehensive characterization of the memory effect arising in thin-junction silicon Single-Photon Avalanche Diodes (SPADs) when exposed to strong illumination. This partially unknown afterpulsing-like noise represents the main limiting factor when time-gated acquisitions are exploited to increase the measurement dynamic range of very fast (picosecond scale) and faint (single-photon) optical signals following a strong stray one. We report the dependences of this unwelcome signal-related noise on photon wavelength, detector temperature, and biasing conditions. Our results suggest that this so-called “memory effect” is generated in the deep regions of the detector, well below the depleted region, and its contribution on detector response is visible only when time-gated SPADs are exploited to reject a strong burst of photons.

  15. Photons & Fusion Newsletter

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

    photons fusion 2012 Photons & Fusion Newsletter August 2012 Photons & Fusion is a monthly review of science and technology at the National Ignition Facility & Photon Science ...

  16. X-ray photonic microsystems for the manipulation of synchrotron...

    Office of Scientific and Technical Information (OSTI)

    (MEMS) when combined with micro-optics have found a wide range of photonics applications. ... for X-rays, a new generation of photonics microsystems for X-ray wavelengths will ...

  17. Photon Science

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

    Photo Gallery The latest photos from NNSA headquarters and across the nuclear security enterprise. The latest photos from NNSA headquarters and across the nuclear security enterprise. Visit us on Flickr

    science Photon Science Along with its primary missions-global security, energy security, basic science, and national competitiveness-the NIF & Photon Science Directorate also pursues research and development projects to innovate and develop cutting-edge technologies in support of those

  18. Photon generator

    DOE Patents [OSTI]

    Srinivasan-Rao, Triveni

    2002-01-01

    A photon generator includes an electron gun for emitting an electron beam, a laser for emitting a laser beam, and an interaction ring wherein the laser beam repetitively collides with the electron beam for emitting a high energy photon beam therefrom in the exemplary form of x-rays. The interaction ring is a closed loop, sized and configured for circulating the electron beam with a period substantially equal to the period of the laser beam pulses for effecting repetitive collisions.

  19. Supersonic metal plasma impact on a surface: An optical investigation of the pre-surface region

    SciTech Connect (OSTI)

    Fusion Science Group, AFRD; Plasma Applications Group, AFRD; Ni, Pavel A.; Anders, Andre

    2009-12-15

    Aluminum plasma, produced in high vacuum by a pulsed, filtered cathodic arc plasma source, was directed onto a wall where if formed a coating. The accompanying ?optical flare? known from the literature was visually observed, photographed, and spectroscopically investigated with appropriately high temporal (1 ?s) and spatial (100 ?m) resolution. Consistent with other observations using different techniques, it was found that the impact of the fully ionized plasma produces metal neutrals as well as desorbed gases, both of which interact with the incoming plasma. Most effectively are charge exchange collisions between doubly charged aluminum and neutral aluminum, which lead to a reduction of the flow of doubly charged before they reach the wall, and a reduction of neutrals as the move away from the surface. Those plasma-wall interactions are relevant for coating processes as well as for interpreting the plasma properties such as ion charge state distributions.

  20. The mystery of spectral breaks: Lyman continuum absorption by photon-photon pair production in the Fermi GeV spectra of bright blazars

    SciTech Connect (OSTI)

    Stern, Boris E. [Institute for Nuclear Research, Russian Academy of Sciences, Prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation); Poutanen, Juri, E-mail: stern.boris@gmail.com, E-mail: juri.poutanen@utu.fi [Tuorla Observatory, University of Turku, Vislntie 20, FI-21500 Piikki (Finland)

    2014-10-10

    We re-analyze Fermi/LAT ?-ray spectra of bright blazars using the new Pass 7 version of the detector response files and detect breaks at ?5 GeV in the rest-frame spectra of 3C 454.3 and possibly also 4C +21.35, associated with the photon-photon pair production absorption by the He II Lyman continuum (LyC). We also detect significant breaks at ?20 GeV associated with hydrogen LyC in both the individual spectra and the stacked redshift-corrected spectrum of several bright blazars. The detected breaks in the stacked spectra univocally prove that they are associated with atomic ultraviolet emission features of the quasar broad-line region (BLR). The dominance of the absorption by the hydrogen Ly complex over He II, a small detected optical depth, and break energy consistent with head-on collisions with LyC photons imply that the ?-ray emission site is located within the BLR, but most of the BLR emission comes from a flat disk-like structure producing little opacity. Alternatively, the LyC emission region size might be larger than the BLR size measured from reverberation mapping, and/or the ?-ray emitting region is extended. These solutions would resolve the long-standing issue of how the multi-hundred GeV photons can escape from the emission zone without being absorbed by softer photons.

  1. Multicolor photonic crystal laser array

    DOE Patents [OSTI]

    Wright, Jeremy B; Brener, Igal; Subramania, Ganapathi S; Wang, George T; Li, Qiming

    2015-04-28

    A multicolor photonic crystal laser array comprises pixels of monolithically grown gain sections each with a different emission center wavelength. As an example, two-dimensional surface-emitting photonic crystal lasers comprising broad gain-bandwidth III-nitride multiple quantum well axial heterostructures were fabricated using a novel top-down nanowire fabrication method. Single-mode lasing was obtained in the blue-violet spectral region with 60 nm of tuning (or 16% of the nominal center wavelength) that was determined purely by the photonic crystal geometry. This approach can be extended to cover the entire visible spectrum.

  2. Structural characterization of thin film photonic crystals

    SciTech Connect (OSTI)

    Subramania, G.; Biswas, R.; Constant, K.; Sigalas, M. M.; Ho, K. M.

    2001-06-15

    We quantitatively analyze the structure of thin film inverse-opal photonic crystals composed of ordered arrays of air pores in a background of titania. Ordering of the sphere template and introduction of the titania background were performed simultaneously in the thin film photonic crystals. Nondestructive optical measurements of backfilling with high refractive index liquids, angle-resolved reflectivity, and optical spectroscopy were combined with band-structure calculations. The analysis reveals a thin film photonic crystal structure with a very high filling fraction (92{endash}94%) of air and a substantial compression along the c axis ({similar_to}22{endash}25%).

  3. FY 2005 Infrared Photonics Final Report

    SciTech Connect (OSTI)

    Anheier, Norman C.; Allen, Paul J.; Ho, Nicolas; Krishnaswami, Kannan; Johnson, Bradley R.; Sundaram, S. K.; Riley, Bradley M.; Martinez, James E.; Qiao, Hong; Schultz, John F.

    2005-12-01

    Research done by the Infrared Photonics team at Pacific Northwest National Laboratory (PNNL) is focused on developing miniaturized integrated optics for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensing applications by exploiting the unique optical and material properties of chalcogenide glass. PNNL has developed thin-film deposition capabilities, direct laser writing techniques, infrared photonic device demonstration, holographic optical element design and fabrication, photonic device modeling, and advanced optical metrologyall specific to chalcogenide glass. Chalcogenide infrared photonics provides a pathway to quantum cascade laser (QCL) transmitter miniaturization. QCLs provide a viable infrared laser source for a new class of laser transmitters capable of meeting the performance requirements for a variety of national security sensing applications. The high output power, small size, and superb stability and modulation characteristics of QCLs make them amenable for integration as transmitters into ultra-sensitive, ultra-selective point sampling and remote short-range chemical sensors that are particularly useful for nuclear nonproliferation missions. During FY 2005, PNNLs Infrared Photonics research team made measurable progress exploiting the extraordinary optical and material properties of chalcogenide glass to develop miniaturized integrated optics for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensing applications. We investigated sulfur purification methods that will eventually lead to routine production of optical quality chalcogenide glass. We also discovered a glass degradation phenomenon and our investigation uncovered the underlying surface chemistry mechanism and developed mitigation actions. Key research was performed to understand and control the photomodification properties. This research was then used to demonstrate several essential infrared photonic devices, including LWIR single-mode waveguide devices and waveguide

  4. Photon antibunching

    SciTech Connect (OSTI)

    Paul, H.

    1982-10-01

    A review is given of recent theoretical studies devoted to the problem of generating radiation fields that exhibit the opposite of the well-known bunching of photons observed in light from thermal sources, the so-called antibunching effect. It is made clear that this phenomenon reflects the corpuscular nature of light and, hence, cannot be interpreted in terms of classical electrodynamics, needing, instead, the quantum-mechanical formalism for its description. It is shown in some detail that nonlinear interaction mechanisms like multiphoton absorption and parametric three-wave interaction are suited to change the photon statistical properties of incident (in most cases coherent) light such that the output field will be endowed with antibunching properties. Special emphasis is given to the problem of correctly specifying the dimensions of the mode volume occurring in the usual single-mode treatment of the field, which is, in fact, of great practical interest, since the magnitude of the antibunching effect is determined by the inverse average number of photons contained in that volume. In a later section it is pointed out that destructive interference with a coherent reference beam provides a means of (a) effectively enhancing photon antibunching that is already present in a high-intensity field, through reduction of the intensity, and (b) transforming phase fluctuations produced in a Kerr medium into antibunching-type intensity fluctuations. On the other hand, there exists a way of directly generating light with antibunching properties, the physical mechanism being resonance fluorescence from a single atom. The main features of this technique, both theoretical and experimental, are outlined, including a discussion of the first experimental results obtained a few years ago.

  5. Nonlinearity sensing via photon-statistics excitation spectroscopy

    SciTech Connect (OSTI)

    Assmann, Marc; Bayer, Manfred

    2011-11-15

    We propose photon-statistics excitation spectroscopy as an adequate tool to describe the optical response of a nonlinear system. To this end we suggest to use optical excitation with varying photon statistics as another spectroscopic degree of freedom to gather information about the system in question. The responses of several simple model systems to excitation beams with different photon statistics are discussed. Possible spectroscopic applications in terms of identifying lasing operation are pointed out.

  6. Methods and systems for Raman and optical cross-interrogation in flow-through silicon membranes

    DOE Patents [OSTI]

    Bond, Tiziana C.; Letant, Sonia E.

    2014-09-09

    Cross-interrogating photonic detection systems and methods are shown. A flow through photonic crystal membrane with a surface enhanced Raman scattering (SERS) substrate is provided with pores which are distributed along multiple regions. The pores of one region have walls to which a first type of target specific anchor can be attached, while pores of another region have walls to which a second type of target specific anchor can be attached. An optical arrangement out-of-plane to the SERS substrate is also provided for enhanced sensitivity and identification of target organisms.

  7. Photon Calorimeter

    DOE Patents [OSTI]

    Chow, Tze-Show

    1989-01-01

    A photon calorimeter (20, 40) is provided that comprises a laminar substrate (10, 22, 42) that is uniform in density and homogeneous in atomic composition. A plasma-sprayed coating (28, 48, 52), that is generally uniform in density and homogeneous in atomic composition within the proximity of planes that are parallel to the surfaces of the substrate, is applied to either one or both sides of the laminar substrate. The plasma-sprayed coatings may be very efficiently spectrally tailored in atomic number. Thermocouple measuring junctions (30, 50, 54) are positioned within the plasma-sprayed coatings. The calorimeter is rugged, inexpensive, and equilibrates in temperature very rapidly.

  8. Photon calorimeter

    DOE Patents [OSTI]

    Chow, Tze-Show

    1988-04-22

    A photon calorimeter is provided that comprises a laminar substrate that is uniform in density and homogeneous in atomic composition. A plasma-sprayed coating, that is generally uniform in density and homogeneous in atomic composition within the proximity of planes that are parallel to the surfaces of the substrate, is applied to either one or both sides of the laminar substrate. The plasma-sprayed coatings may be very efficiently spectrally tailored in atomic number. Thermocouple measuring junctions, are positioned within the plasma-sprayed coatings. The calorimeter is rugged, inexpensive, and equilibrates in temperature very rapidly. 4 figs.

  9. Continuous Energy MC Neutron/Photon

    Energy Science and Technology Software Center (OSTI)

    1991-10-10

    VIM solves the three-dimensional steady-state multiplication eigenvalue or fixed source neutron or photon (VIM3.0) transport problem using continuous energy-dependent nuclear data. It was designed for the analysis of fast critical experiments. In VIM3.0, the photon interactions i.e., pair production, coherent and incoherent scattering, and photoelectric events, and photon heating are tallied by group, region, and isotope.

  10. Lightwave Circuits in Lithium Niobate through Hybrid Waveguides with Silicon Photonics

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

    Weigel, Peter O.; Savanier, Marc; DeRose, Christopher T.; Pomerene, Andrew T.; Starbuck, Andrew L.; Lentine, Anthony L.; Stenger, Vincent; Mookherjea, Shayan

    2016-03-01

    Here we demonstrate a photonic waveguide technology based on a two-material core, in which light is controllably and repeatedly transferred back and forth between sub-micron thickness crystalline layers of Si and LN bonded to one another, where the former is patterned and the latter is not. In this way, the foundry-based wafer-scale fabrication technology for silicon photonics can be leveraged to form lithium-niobate based integrated optical devices. Using two different guided modes and an adiabatic mode transition between them, we demonstrate a set of building blocks such as waveguides, bends, and couplers which can be used to route light underneathmore » an unpatterned slab of LN, as well as outside the LN-bonded region, thus enabling complex and compact lightwave circuits in LN alongside Si photonics with fabrication ease and low cost.« less

  11. Photonic Heterostructures with Properties of Ferroelectrics and Light Polarizers

    SciTech Connect (OSTI)

    Palto, S. P. Draginda, Yu. A.

    2010-11-15

    The optical and electro-optical properties of a new type of photonic heterostructure composed of alternating ferroelectric molecular layers and optically anisotropic layers of another material are considered. A numerical simulation of the real prototype of this heterostructure, which can be prepared by the Langmuir-Blodgett method from layers of a ferroelectric copolymer (polyvinylidene fluoride trifluoroethylene) and an azo dye with photoinduced optical anisotropy, has been performed. It is shown that this heterostructure has pronounced polarization optical properties and yields a significant change in the polarization state of light at the photonic band edges in the ranges of the maximum density of photon states. The latter property can be used to obtain an enhanced electro-optic effect at small spectral shifts of the photonic band (the latter can be provided by the piezoelectric effect in ferroelectric layers).

  12. Optical XOR gate

    DOE Patents [OSTI]

    Vawter, G. Allen

    2013-11-12

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

  13. Enhanced optical power of GaN-based light-emitting diode with compound photonic crystals by multiple-exposure nanosphere-lens lithography

    SciTech Connect (OSTI)

    Zhang, Yonghui; Wei, Tongbo, E-mail: tbwei@semi.ac.cn; Xiong, Zhuo; Shang, Liang; Tian, Yingdong; Zhao, Yun; Zhou, Pengyu; Wang, Junxi; Li, Jinmin [Semiconductor Lighting Technology Research and Development Center, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2014-07-07

    The light-emitting diodes (LEDs) with single, twin, triple, and quadruple photonic crystals (PCs) on p-GaN are fabricated by multiple-exposure nanosphere-lens lithography (MENLL) process utilizing the focusing behavior of polystyrene spheres. Such a technique is easy and economical for use in fabricating compound nano-patterns. The optimized tilted angle is decided to be 26.6 through mathematic calculation to try to avoid the overlay of patterns. The results of scanning electron microscopy and simulations reveal that the pattern produced by MENLL is a combination of multiple ovals. Compared to planar-LED, the light output power of LEDs with single, twin, triple, and quadruple PCs is increased by 14.78%, 36.03%, 53.68%, and 44.85% under a drive current 350?mA, respectively. Furthermore, all PC-structures result in no degradation of the electrical properties. The stimulated results indicate that the highest light extraction efficiency of LED with the clover-shape triple PC is due to the largest scattering effect on propagation of light from GaN into air.

  14. Resonance formation in photon-photon collisions

    SciTech Connect (OSTI)

    Gidal, G.

    1988-08-01

    Recent experimental progress on resonance formation in photon-photon collisions is reviewed with particular emphasis on the pseudoscalar and tensor nonents and on the ..gamma gamma..* production of spin-one resonances. 37 refs., 17 figs., 5 tabs.

  15. Photon Energy Services Photon | Open Energy Information

    Open Energy Info (EERE)

    the design and implementation of the solar PV system as well as the provision of maintenance. References: Photon Energy Services (Photon)1 This article is a stub. You can...

  16. Athermalization of resonant optical devices via thermo-mechanical feedback

    DOE Patents [OSTI]

    Rakich, Peter; Nielson, Gregory N.; Lentine, Anthony L.

    2016-01-19

    A passively athermal photonic system including a photonic circuit having a substrate and an optical cavity defined on the substrate, and passive temperature-responsive provisions for inducing strain in the optical cavity of the photonic circuit to compensate for a thermo-optic effect resulting from a temperature change in the optical cavity of the photonic circuit. Also disclosed is a method of passively compensating for a temperature dependent thermo-optic effect resulting on an optical cavity of a photonic circuit including the step of passively inducing strain in the optical cavity as a function of a temperature change of the optical cavity thereby producing an elasto-optic effect in the optical cavity to compensate for the thermo-optic effect resulting on an optical cavity due to the temperature change.

  17. Photons & Fusion Newsletter

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

    June 2013 Photons & Fusion is a monthly review of science and technology at the National Ignition Facility & Photon Science Directorate. For more information, submit a question....

  18. Improvement of lateral resolution of spectral domain optical coherence tomography images in out-of-focus regions with holographic data processing techniques

    SciTech Connect (OSTI)

    Moiseev, A A; Gelikonov, G V; Terpelov, D A; Shilyagin, P A; Gelikonov, V M

    2014-08-31

    An analogy between spectral-domain optical coherence tomography (SD OCT) data and broadband digital holography data is considered. Based on this analogy, a method for processing SD OCT data, which makes it possible to construct images with a lateral resolution in the whole investigated volume equal to the resolution in the in-focus region, is developed. Several issues concerning practical application of the proposed method are discussed. (laser biophotonics)

  19. Superconducting nanowire single photon detector on diamond

    SciTech Connect (OSTI)

    Atikian, Haig A.; Burek, Michael J.; Choy, Jennifer T.; Lon?ar, Marko; Eftekharian, Amin; Jafari Salim, A.; Hamed Majedi, A.

    2014-03-24

    Superconducting nanowire single photon detectors are fabricated directly on diamond substrates and their optical and electrical properties are characterized. Dark count performance and photon count rates are measured at varying temperatures for 1310?nm and 632?nm photons. A multi-step diamond surface polishing procedure is reported, involving iterative reactive ion etching and mechanical polishing to create a suitable diamond surface for the deposition and patterning of thin film superconducting layers. Using this approach, diamond substrates with less than 300?pm Root Mean Square surface roughness are obtained.

  20. Quantum Enabled Security (QES) for Optical Communications

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

    Laboratory has developed Quantum Enabled Security (QES), a revolutionary new cybersecurity capability using quantum (single-photon) communications integrated with optical...

  1. Light trapping in thin film solar cells using textured photonic crystal

    DOE Patents [OSTI]

    Yi, Yasha; Kimerling, Lionel C.; Duan, Xiaoman; Zeng, Lirong

    2009-01-27

    A solar cell includes a photoactive region that receives light. A photonic crystal is coupled to the photoactive region, wherein the photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light.

  2. Photon-Photon Collisions -- Past and Future

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC

    2005-12-02

    I give a brief review of the history of photon-photon physics and a survey of its potential at future electron-positron colliders. Exclusive hadron production processes in photon-photon and electron-photon collisions provide important tests of QCD at the amplitude level, particularly as measures of hadron distribution amplitudes. There are also important high energy {gamma}{gamma} and e{gamma} tests of quantum chromodynamics, including the production of jets in photon-photon collisions, deeply virtual Compton scattering on a photon target, and leading-twist single-spin asymmetries for a photon polarized normal to a production plane. Since photons couple directly to all fundamental fields carrying the electromagnetic current including leptons, quarks, W's and supersymmetric particles, high energy {gamma}{gamma} collisions will provide a comprehensive laboratory for Higgs production and exploring virtually every aspect of the Standard Model and its extensions. High energy back-scattered laser beams will thus greatly extend the range of physics of the International Linear Collider.

  3. XrayOpticsConstants

    Energy Science and Technology Software Center (OSTI)

    2005-06-20

    This application (XrayOpticsConstants) is a tool for displaying X-ray and Optical properties for a given material, x-ray photon energy, and in the case of a gas, pressure. The display includes fields such as the photo-electric absorption attenuation length, density, material composition, index of refraction, and emission properties (for scintillator materials).

  4. Scalable optical quantum computer

    SciTech Connect (OSTI)

    Manykin, E A; Mel'nichenko, E V [Institute for Superconductivity and Solid-State Physics, Russian Research Centre 'Kurchatov Institute', Moscow (Russian Federation)

    2014-12-31

    A way of designing a scalable optical quantum computer based on the photon echo effect is proposed. Individual rare earth ions Pr{sup 3+}, regularly located in the lattice of the orthosilicate (Y{sub 2}SiO{sub 5}) crystal, are suggested to be used as optical qubits. Operations with qubits are performed using coherent and incoherent laser pulses. The operation protocol includes both the method of measurement-based quantum computations and the technique of optical computations. Modern hybrid photon echo protocols, which provide a sufficient quantum efficiency when reading recorded states, are considered as most promising for quantum computations and communications. (quantum computer)

  5. Soft X-ray microscopy in the spectral region of 'carbon window' with the use of multilayer optics and a laser-plasma source

    SciTech Connect (OSTI)

    Artyukov, I. A. Vinogradov, A. V.; Bugayev, Ye. A.; Devizenko, A. Yu.; Kondratenko, V. V.; Kasyanov, Yu. S.

    2009-11-15

    This paper reports on the fabrication and testing of multilayer mirrors for X-ray optical systems operating in the 'carbon window' region (at wavelengths from 4.5 to 5.0 nm) and the results of their application in soft X-ray imaging of the internal structure of organic objects. The developed approaches to the fabrication and control of graded Co/C multilayer coatings have made it possible to create an X-ray multimirror system with a maximum known entrance aperture and throughput. The use of the developed high-spatial-resolution X-ray optics can significantly extend the field of practical application of soft X-ray absorption microscopy based on compact laser-plasma sources.

  6. Di-photon and photon + b/c production cross sections at Ecm = 1.96- TeV

    SciTech Connect (OSTI)

    Gajjar, Anant; /Liverpool U.

    2005-05-01

    Measurements of the di-photon cross section have been made in the central region and are found to be in good agreement with NLO QCD predictions. The cross section of events containing a photon and additional heavy flavor jet have also been measured, as well as the ratio of photon + b to photon + c. The statistically limited sample shows good agreement with Leading Order predictions.

  7. Coherence revivals in two-photon frequency combs

    SciTech Connect (OSTI)

    Torres-Company, Victor; Lancis, Jesus; Lajunen, Hanna; Friberg, Ari T.

    2011-09-15

    We describe and theoretically analyze the self-imaging Talbot effect of entangled photon pairs in the time domain. Rich phenomena are observed in coherence propagation along dispersive media of mode-locked two-photon states with frequency entanglement exhibiting a comblike correlation function. Our results can be used to remotely transfer frequency standards through optical fiber networks with two-photon light, avoiding the requirement of dispersion compensation.

  8. Photonic Doppler Velocimetry Multiplexing Techniques: Evaluation of Photonic Techniques

    SciTech Connect (OSTI)

    Edward Daykin

    2012-05-24

    This poster reports progress related to photonic technologies. Specifically, the authors developed diagnostic system architecture for a Multiplexed Photonic Doppler Velocimetry (MPDV) that incorporates frequency and time-division multiplexing into existing PDV methodology to provide increased channel count. Current MPDV design increases number of data records per digitizer channel 8x, and also operates as a laser-safe (Class 3a) system. Further, they applied heterodyne interferometry to allow for direction-of-travel determination and enable high-velocity measurements (>10 km/s) via optical downshifting. They also leveraged commercially available, inexpensive and robust components originally developed for telecom applications. Proposed MPDV architectures employ only commercially available, fiber-coupled hardware.

  9. Atmospheric optical calibration system

    DOE Patents [OSTI]

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

    1988-10-25

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

  10. Atmospheric optical calibration system

    DOE Patents [OSTI]

    Hulstrom, Roland L.; Cannon, Theodore W.

    1988-01-01

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

  11. Backconversion-limited optical parametric oscillators

    DOE Patents [OSTI]

    Alford, William J.; Smith, Arlee V.

    2000-11-14

    A more efficient class of optical parametric oscillators is made possible by introducing means for reducing signal losses due to backconversion of signal photons in the nonlinear optical medium.

  12. The Importance of Photonics Technology | GE Global Research

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

    at Global Research. I would like to further highlight the importance of Photonics and Optics by pointing to a recent report written by the US National Academies with the help of...

  13. AE Photonics | Open Energy Information

    Open Energy Info (EERE)

    Photonics Jump to: navigation, search Name: AE Photonics Place: Germany Product: Germany-based PV system and component supplier References: AE Photonics1 This article is a stub....

  14. Design, Assembly, and Testing of a Photon Doppler Velocimetry Probe

    SciTech Connect (OSTI)

    Malone, Robert M; Cox, Brian C; Daykin, Edward P; DeVore, Douglas O; Esquibel, David L; Frayer, Daniel K; Frogget, Brent C; Gallegos, Cenobio H; Kaufman, Morris I; McGillivray, Kevin D; Romero, Vincent T; Briggs, Matthew E; Furlanetto, Michael R; Holtkamp, David B; Pazuchanics, Peter; Primas, Lori E; Shinas, Michael A

    2011-08-21

    A novel fiber-optic probe measures the velocity distribution of an imploding surface along many lines of sight. Reflected light from each spot on the moving surface is Doppler shifted with a small portion of this light propagating backwards through the launching fiber. The reflected light is mixed with a reference laser in a technique called photon Doppler velocimetry, providing continuous time records. Within the probe, a matrix array of 56 single-mode fibers sends light through an optical relay consisting of three types of lenses. Seven sets of these relay lenses are grouped into a close-packed array allowing the interrogation of seven regions of interest. A six-faceted prism with a hole drilled into its center directs the light beams to the different regions. Several types of relay lens systems have been evaluated, including doublets and molded aspheric singlets. The optical design minimizes beam diameters and also provides excellent imaging capabilities. One of the fiber matrix arrays can be replaced by an imaging coherent bundle. This close-packed array of seven relay systems provides up to 476 beam trajectories. The pyramid prism has its six facets polished at two different angles that will vary the density of surface point coverage. Fibers in the matrix arrays are angle polished at 8{sup o} to minimize back reflections. This causes the minimum beam waist to vary along different trajectories. Precision metrology on the direction cosine trajectories is measured to satisfy environmental requirements for vibration and temperature.

  15. Photonic Design for Photovoltaics

    SciTech Connect (OSTI)

    Kosten, E.; Callahan, D.; Horowitz, K.; Pala, R.; Atwater, H.

    2014-08-28

    We describe photonic design approaches for silicon photovoltaics including i) trapezoidal broadband light trapping structures ii) broadband light trapping with photonic crystal superlattices iii) III-V/Si nanowire arrays designed for broadband light trapping.

  16. Integrated nonlinear photonics: Emerging applications and ongoing challenges - A mini review

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

    Hendrickson, Scott M.; Foster, Amy C.; Camacho, Ryan M.; Clader, B. David

    2014-11-26

    In this paper, we provide a review of recent progress in integrated nonlinear photonics with a focus on emerging applications in all-optical signal processing, ultra-low-power all-optical switching, and quantum information processing.

  17. Integrated nonlinear photonics. Emerging applications and ongoing challenges - A mini review

    SciTech Connect (OSTI)

    Hendrickson, Scott M.; Foster, Amy C.; Camacho, Ryan M.; Clader, B. David

    2014-11-26

    In this paper, we provide a review of recent progress in integrated nonlinear photonics with a focus on emerging applications in all-optical signal processing, ultra-low-power all-optical switching, and quantum information processing.

  18. Optical and magneto-optical studies of martensitic transformation...

    Office of Scientific and Technical Information (OSTI)

    Magneto-optical spectroscopy and spectroscopic ellipsometry were measured in the sample temperature range from 297 to 373 K and photon energy range from 1.2 to 6.5 eV. ...

  19. Yoctosecond Photon Pulses from Quark-Gluon Plasmas

    SciTech Connect (OSTI)

    Ipp, Andreas; Keitel, Christoph H.; Evers, Joerg

    2009-10-09

    Present ultrafast laser optics is at the frontier between atto- and zeptosecond photon pulses, giving rise to unprecedented applications. We show that high-energetic photon pulses down to the yoctosecond time scale can be produced in heavy-ion collisions. We focus on photons produced during the initial phase of the expanding quark-gluon plasma. We study how the time evolution and properties of the plasma may influence the duration and shape of the photon pulse. Prospects for achieving double-peak structures suitable for pump-probe experiments at the yoctosecond time scale are discussed.

  20. Lasing modes in polycrystalline and amorphous photonic structures

    SciTech Connect (OSTI)

    Yang, Jin-Kyu; Noh, Heeso; Liew, Seng Fatt; Rooks, Michael J.; Solomon, Glenn S.; Cao Hui

    2011-09-15

    We systematically studied the lasing characteristics in photonic polycrystalline and amorphous structures. 2D arrays of air holes were fabricated in a GaAs membrane. InAs quantum dots embedded in the membrane provide gain for lasing under optical pumping. The lasing modes are spatially localized, and blue shift as the structural order becomes short ranged. Our three-dimensional numerical simulations reveal that the out-of-plane leakage of the lasing mode dominates over the in-plane leakage. The lasing modes in a photonic polycrystalline move away from the center frequency of the photonic band gap to reduce the out-of-plane leakage. In a photonic amorphous structure, the short-range order improves optical confinement and enhances the quality factor of resonances. Understanding the behavior of photonic polycrystalline laser and amorphous laser opens the possibility of controlling lasing characteristic by varying the degree of structural order.

  1. Photonic crystal devices formed by a charged-particle beam

    DOE Patents [OSTI]

    Lin, Shawn-Yu; Koops, Hans W. P.

    2000-01-01

    A photonic crystal device and method. The photonic crystal device comprises a substrate with at least one photonic crystal formed thereon by a charged-particle beam deposition method. Each photonic crystal comprises a plurality of spaced elements having a composition different from the substrate, and may further include one or more impurity elements substituted for spaced elements. Embodiments of the present invention may be provided as electromagnetic wave filters, polarizers, resonators, sources, mirrors, beam directors and antennas for use at wavelengths in the range from about 0.2 to 200 microns or longer. Additionally, photonic crystal devices may be provided with one or more electromagnetic waveguides adjacent to a photonic crystal for forming integrated electromagnetic circuits for use at optical, infrared, or millimeter-wave frequencies.

  2. Photonically Engineered Incandescent Emitter

    DOE Patents [OSTI]

    Gee, James M.; Lin, Shawn-Yu; Fleming, James G.; Moreno, James B.

    2005-03-22

    A photonically engineered incandescence is disclosed. The emitter materials and photonic crystal structure can be chosen to modify or suppress thermal radiation above a cutoff wavelength, causing the emitter to selectively emit in the visible and near-infrared portions of the spectrum. An efficient incandescent lamp is enabled thereby. A method for fabricating a three-dimensional photonic crystal of a structural material, suitable for the incandescent emitter, is also disclosed.

  3. Photonically engineered incandescent emitter

    DOE Patents [OSTI]

    Gee, James M.; Lin, Shawn-Yu; Fleming, James G.; Moreno, James B.

    2003-08-26

    A photonically engineered incandescence is disclosed. The emitter materials and photonic crystal structure can be chosen to modify or suppress thermal radiation above a cutoff wavelength, causing the emitter to selectively emit in the visible and near-infrared portions of the spectrum. An efficient incandescent lamp is enabled thereby. A method for fabricating a three-dimensional photonic crystal of a structural material, suitable for the incandescent emitter, is also disclosed.

  4. Magnetic field role on the structure and optical response of photonic crystals based on ferrofluids containing Co{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} nanoparticles

    SciTech Connect (OSTI)

    Lpez, J. Gonzlez, Luz E.; Quionez, M. F.; Gmez, M. E.; Porras-Montenegro, N.; Zambrano, G.

    2014-05-21

    Ferrofluids based on magnetic Co{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} ferrite nanoparticles were prepared by co-precipitation method from aqueous salt solutions of Co (II), ZnSO{sub 4}, and Fe (III) in an alkaline medium. Ferrofluids placed in an external magnetic field show properties that make them interesting as magneto-controllable soft photonic crystals. Morphological and structural characterizations of the samples were obtained from Scanning Electron Microscopy and Transmission Electron Microscopy studies. Magnetic properties were investigated with the aid of a vibrating sample magnetometer at room temperature. Herein, the Co{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} samples showed superparamagnetic behavior, according to hysteresis loop results. Taking in mind that the Co-Zn ferrite hysteresis loop is very small, our magnetic nanoparticles can be considered soft magnetic material with interesting technological applications. In addition, by using the plane-wave expansion method, we studied the photonic band structure of 2D photonic crystals made of ferrofluids with the same nanoparticles. Previous experimental results show that a magnetic field applied perpendicular to the ferrofluid plane agglomerates the magnetic nanoparticles in parallel rods to form a hexagonal 2D photonic crystal. We calculated the photonic band structure of photonic crystals by means of the effective refractive index of the magnetic fluid, basing the study on the Maxwell-Garnett theory, finding that the photonic band structure does not present any band gaps under the action of applied magnetic field strengths used in our experimental conditions.

  5. Overview | Advanced Photon Source

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

    APS Overview: Introduction APS Systems Map LINAC Booster Synchrotron Storage Ring Insertion Devices Experiment Hall LOMs & Beamlines Overview of the APS The Advanced Photon Source...

  6. Photons & Fusion Newsletter

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

    2 Photons & Fusion Newsletter May 2012 Reducing the Time to Grow Good Cryogenic Layers One of the most demanding aspects of preparing targets for NIF ignition experiments is...

  7. Beamlines | Advanced Photon Source

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

    Beamlines Beamlines Home Beamlines Directory Research Techniques Sectors Directory Status and Schedule Safety and Training Beamlines The Advanced Photon Source consists of 34...

  8. Photonics | GE Global Research

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

    Home > Impact > The Photonics Lab at GE Global Research Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) The Photonics Lab at GE Global Research Loucas Tsakalakos, the Photonics lab manager at GE Global Research, introduces photonics and shares the lab's work on innovative ways to use light. You Might Also Like

  9. Resonances in photon-photon scattering

    SciTech Connect (OSTI)

    Chanowitz, M.S.

    1988-06-01

    Selected topics in meson spectroscoy are reviewed as they are illuminated by photon-photon collisons. Subjects include the S*/f/sub 0/ (975) and delta/a/sub 0/ (980) as /ovr qq/qq candidates, the /iota///eta/ (1460) and theta/f/sub 2/ (1700) as glueball candidates, and the spin 1 X(1420) seen in tagged events which represents new physics whether its parity is positive, J/sup PC/ = 1/sup + +/, or negative with exotic J/sup PC/ = 1/sup /minus/+/. 57 refs., 2 figs., 1 tab.

  10. Photon beam position monitor

    DOE Patents [OSTI]

    Kuzay, T.M.; Shu, D.

    1995-02-07

    A photon beam position monitor is disclosed for use in the front end of a beamline of a high heat flux and high energy photon source such as a synchrotron radiation storage ring detects and measures the position and, when a pair of such monitors are used in tandem, the slope of a photon beam emanating from an insertion device such as a wiggler or an undulator inserted in the straight sections of the ring. The photon beam position monitor includes a plurality of spaced blades for precisely locating the photon beam, with each blade comprised of chemical vapor deposition (CVD) diamond with an outer metal coating of a photon sensitive metal such as tungsten, molybdenum, etc., which combination emits electrons when a high energy photon beam is incident upon the blade. Two such monitors are contemplated for use in the front end of the beamline, with the two monitors having vertically and horizontally offset detector blades to avoid blade ''shadowing''. Provision is made for aligning the detector blades with the photon beam and limiting detector blade temperature during operation. 18 figs.

  11. Photon beam position monitor

    DOE Patents [OSTI]

    Kuzay, Tuncer M.; Shu, Deming

    1995-01-01

    A photon beam position monitor for use in the front end of a beamline of a high heat flux and high energy photon source such as a synchrotron radiation storage ring detects and measures the position and, when a pair of such monitors are used in tandem, the slope of a photon beam emanating from an insertion device such as a wiggler or an undulator inserted in the straight sections of the ring. The photon beam position monitor includes a plurality of spaced blades for precisely locating the photon beam, with each blade comprised of chemical vapor deposition (CVD) diamond with an outer metal coating of a photon sensitive metal such as tungsten, molybdenum, etc., which combination emits electrons when a high energy photon beam is incident upon the blade. Two such monitors are contemplated for use in the front end of the beamline, with the two monitors having vertically and horizontally offset detector blades to avoid blade "shadowing". Provision is made for aligning the detector blades with the photon beam and limiting detector blade temperature during operation.

  12. A micron resolution optical scanner for characterization of silicon detectors

    SciTech Connect (OSTI)

    Shukla, R. A.; Dugad, S. R. Gopal, A. V.; Gupta, S. K.; Prabhu, S. S.; Garde, C. S.

    2014-02-15

    The emergence of high position resolution (?10 ?m) silicon detectors in recent times have highlighted the urgent need for the development of new automated optical scanners of micron level resolution suited for characterizing microscopic features of these detectors. More specifically, for the newly developed silicon photo-multipliers (SiPM) that are compact, possessing excellent photon detection efficiency with gain comparable to photo-multiplier tube. In a short time, since their invention the SiPMs are already being widely used in several high-energy physics and astrophysics experiments as the photon readout element. The SiPM is a high quantum efficiency, multi-pixel photon counting detector with fast timing and high gain. The presence of a wide variety of photo sensitive silicon detectors with high spatial resolution requires their performance evaluation to be carried out by photon beams of very compact spot size. We have designed a high resolution optical scanner that provides a monochromatic focused beam on a target plane. The transverse size of the beam was measured by the knife-edge method to be 1.7 ?m at 1 ? ? level. Since the beam size was an order of magnitude smaller than the typical feature size of silicon detectors, this optical scanner can be used for selective excitation of these detectors. The design and operational details of the optical scanner, high precision programmed movement of target plane (0.1 ?m) integrated with general purpose data acquisition system developed for recording static and transient response photo sensitive silicon detector are reported in this paper. Entire functionality of scanner is validated by using it for selective excitation of individual pixels in a SiPM and identifying response of active and dead regions within SiPM. Results from these studies are presented in this paper.

  13. Photons & Fusion Newsletter - 2014

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

    Discovery Science on NIF: Exploring the Physics of Star Formation Article on MOIRE Optics on Cover of Applied Optics Mode 1 Drive Asymmetry in NIF Inertial Confinement Fusion...

  14. Projection imaging of photon beams by the Cerenkov effect

    SciTech Connect (OSTI)

    Glaser, Adam K.; Davis, Scott C.; McClatchy, David M.; Zhang, Rongxiao; Pogue, Brian W.; Gladstone, David J.

    2013-01-15

    Purpose: A novel technique for beam profiling of megavoltage photon beams was investigated for the first time by capturing images of the induced Cerenkov emission in water, as a potential surrogate for the imparted dose in irradiated media. Methods: A high-sensitivity, intensified CCD camera (ICCD) was configured to acquire 2D projection images of Cerenkov emission from a 4 Multiplication-Sign 4 cm{sup 2} 6 MV linear accelerator (LINAC) x-ray photon beam operating at a dose rate of 400 MU/min incident on a water tank with transparent walls. The ICCD acquisition was gated to the LINAC sync pulse to reduce background light artifacts, and the measurement quality was investigated by evaluating the signal to noise ratio and measurement repeatability as a function of delivered dose. Monte Carlo simulations were used to derive a calibration factor for differences between the optical images and deposited dose arising from the anisotropic angular dependence of Cerenkov emission. Finally, Cerenkov-based beam profiles were compared to a percent depth dose (PDD) and lateral dose profile at a depth of d{sub max} from a reference dose distribution generated from the clinical Varian ECLIPSE treatment planning system (TPS). Results: The signal to noise ratio was found to be 20 at a delivered dose of 66.6 cGy, and proportional to the square root of the delivered dose as expected from Poisson photon counting statistics. A 2.1% mean standard deviation and 5.6% maximum variation in successive measurements were observed, and the Monte Carlo derived calibration factor resulted in Cerenkov emission images which were directly correlated to deposited dose, with some spatial issues. The dose difference between the TPS and PDD predicted by Cerenkov measurements was within 20% in the buildup region with a distance to agreement (DTA) of 1.5-2 mm and {+-}3% at depths beyond d{sub max}. In the lateral profile, the dose difference at the beam penumbra was within {+-}13% with a DTA of 0-2 mm

  15. Sandia National Labs: PCNSC: Research: Optical Sciences

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

    Optical Sciences The focus of the Optical Sciences thrust is to understand and exploit the elegant interaction between light and matter. Our research portfolio encompasses the generation, transmission, manipulation, and detection of light and the development of optical materials with user defined characteristics. We emphasize innovative work in laser and optical materials development, nonlinear optics, spectroscopy, remote sensing, and photon-material interactions. In partnership with our DOE,

  16. Method for Creating Photonic Band Gap Materials - Energy Innovation Portal

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

    Method for Creating Photonic Band Gap Materials Ames Laboratory Contact AMES About This Technology Technology Marketing Summary Innovative microstructures that can direct light in a manner similar to the way semiconductors can influence electrons can be produced by creating what is termed a photonic band gap. These microstructures have the potential to change the way optoelectronic devices, such as photodiodes, LEDs, and integrated optical circuit elements, are designed and used. Ames Laboratory

  17. Electronic and photonic power applications

    SciTech Connect (OSTI)

    Walko, R.J.; Ashley, C.S.; Brinker, C.J.; Reed, S.T.; Renschler, C.L. ); Shepodd, T.J. ); Ellefson, R.E.; Gill, J.T. ); Leonard, L.E. )

    1990-01-01

    Efficient conversion of radioactive decay to electrical power has been the goal of a number of past research efforts. One of these was the Elgin-Kidde nuclear battery. In this concept promethium-147 was used as a beta source which was then mixed with a phosphor to produce a radioluminescent (RL) source of light. The light source was coupled to silicon photovoltaic converters to create electricity. This photoelectric approach is being revisited using tritium based solid state compounds and advanced gas concepts to produce RL light sources being disclosed at this conference. Efficient conversion of the RL light energy to electrical energy imposes certain requirements on the semiconductor converter. These requirements will be discussed. Projections of power source electrical and physical characteristics will be presented based on reasonable design parameter assumptions. The words Power Supply'' usually evoke a vision of a rotating machine or chemical battery. However, today's technology is making increasing use of photonics, where information and even power can be moved through optical fibers. Brighter volumetric RL light sources open a whole new range of photonics-based applications, while solid state tritiated compounds provide the foundation for improved mechanical adaptability and safety. 4 refs., 6 figs., 1 tab.

  18. Photon detector system

    DOE Patents [OSTI]

    Ekstrom, Philip A.

    1981-01-01

    A photon detector includes a semiconductor device, such as a Schottky barrier diode, which has an avalanche breakdown characteristic. The diode is cooled to cryogenic temperatures to eliminate thermally generated charge carriers from the device. The diode is then biased to a voltage level exceeding the avalanche breakdown threshold level such that, upon receipt of a photon, avalanche breakdown occurs. This breakdown is detected by appropriate circuitry which thereafter reduces the diode bias potential to a level below the avalanche breakdown threshold level to terminate the avalanche condition. Subsequently, the bias potential is reapplied to the diode in preparation for detection of a subsequently received photon.

  19. Photons & Fusion Newsletter - 2014

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

    news Photons & Fusion Newsletter - 2014 May ARC Beamlet Profiles NIF Petawatt Laser Is on ... An article in the Feb. 12 online issue of the journal Nature reports that fusion fuel ...

  20. Photonics Research and Development

    SciTech Connect (OSTI)

    Pookpanratana, Sujitra; Shlayan, Neveen; Venkat, Rama; Das, Bisjwajit; Boehm, Bob; Heske, Clemens; Fraser, Donald; Moustakas, Theodore

    2010-01-15

    During the period August 2005 through October 2009, the UNLV Research Foundation (UNLVRF), a non-profit affiliate of the University of Nevada, Las Vegas (UNLV), in collaboration with UNLV’s Colleges of Science and Engineering; Boston University (BU); Oak Ridge National Laboratory (ORNL); and Sunlight Direct, LLC, has managed and conducted a diverse and comprehensive research and development program focused on light-emitting diode (LED) technologies that provide significantly improved characteristics for lighting and display applications. This final technical report provides detailed information on the nature of the tasks, the results of the research, and the deliverables. It is estimated that about five percent of the energy used in the nation is for lighting homes, buildings and streets, accounting for some 25 percent of the average home’s electric bill. However, the figure is significantly higher for the commercial sector. About 60 percent of the electricity for businesses is for lighting. Thus replacement of current lighting with solid-state lighting technology has the potential to significantly reduce this nation’s energy consumption – by some estimates, possibly as high as 20%. The primary objective of this multi-year R&D project has been to develop and advance lighting technologies to improve national energy conversion efficiencies; reduce heat load; and significantly lower the cost of conventional lighting technologies. The UNLVRF and its partners have specifically focused these talents on (1) improving LED technologies; (2) optimizing hybrid solar lighting, a technology which potentially offers the benefits of blending natural with artificial lighting systems, thus improving energy efficiency; and (3) building a comprehensive academic infrastructure within UNLV which concentrates on photonics R&D. Task researchers have reported impressive progress in (1) the development of quantum dot laser emitting diodes (QDLEDs) which will ultimately

  1. Photon Source Parameters

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

    Photon Source Parameters Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They

  2. Narrow-band optical transmission of metallic nanoslit arrays

    SciTech Connect (OSTI)

    Sun Zhijun; Yang Ying; Zuo Xiaoliu

    2012-10-22

    Metallic nanoslit arrays usually demonstrate wide transmission bands for transverse-magnetic-polarized incidence light. Here, we show that by introducing multi-dielectric layers underneath the metallic structure layer on the substrate, a narrow peak is formed, whose bandwidth can be down to a few nanometers. Three types of resonance modes in the region under the metal layer are identified responsible for the formation of the peak, i.e., a two-dimensional cavity resonance mode, which supports optical transmission, and two in-plane hybrid surface plasmon resonance modes locating on both sides of the peak that suppresses the transmission. Such structures can be applied in advanced photonic devices.

  3. Microcavity Polaritonics: Optically-Steering Interacting Quantum...

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

    Bio: Prof. Jeremy J. Baumberg FRS, directs a UK Nano-Photonics Centre at the University of Cambridge and has extensive experience in developing optical materials structured on the ...

  4. Photons & Fusion Newsletter - 2014

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

    ... Study of 'Native' Laser Damage Precursors Described in Optics Express In a paper in the Feb. 10 issue of Optics Express, LLNL researchers Nan Shen, Jeff Bude, and Christopher Carr ...

  5. Femtosecond optical clock

    SciTech Connect (OSTI)

    Bagaev, Sergei N; Denisov, Vladimir I; Zakharyash, Valerii F; Kashirsky, Aleksandr V; Klementyev, Vasilii M; Kuznetsov, Sergei A; Korel', I I; Pivtsov, V S

    2004-12-31

    New advances in the field of synthesis of optical frequencies and the development of a new generation of optical clocks are considered. The use of mode-locked femtosecond lasers and fibre emission-spectrum stretchers allows the synthesis of any frequencies (from radio-frequencies to the UV region) and drastically simplifies the structure of an optical clock. The schemes of femtosecond optical clock are presented and the application of tapered optical fibres in them is described. (optical metrology and quantum frequency standards)

  6. Photon detector configured to employ the Gunn effect and method of use

    DOE Patents [OSTI]

    Cich, Michael J

    2015-03-17

    Embodiments disclosed herein relate to photon detectors configured to employ the Gunn effect for detecting high-energy photons (e.g., x-rays and gamma rays) and methods of use. In an embodiment, a photon detector for detecting high-energy photons is disclosed. The photon detector includes a p-i-n semiconductor diode having a p-type semiconductor region, an n-type semiconductor region, and a compensated i-region disposed between the p-type semiconductor region and the n-type semiconductor region. The compensated i-region and has a width of about 100 .mu.m to about 400 .mu.m and is configured to exhibit the Gunn effect when the p-i-n semiconductor diode is forward biased a sufficient amount. The compensated i-region is doped to include a free carrier concentration of less than about 10.sup.10 cm.sup.-3.

  7. Infrared (IR) photon-sensitive spectromicroscopy in a cryogenic environment

    DOE Patents [OSTI]

    Pereverzev, Sergey

    2016-06-14

    A system designed to suppress thermal radiation background and to allow IR single-photon sensitive spectromicroscopy of small samples by using both absorption, reflection, and emission/luminescence measurements. The system in one embodiment includes: a light source; a plurality of cold mirrors configured to direct light along a beam path; a cold or warm sample holder in the beam path; windows of sample holder (or whole sample holder) are transparent in a spectral region of interest, so they do not emit thermal radiation in the same spectral region of interest; a cold monochromator or other cold spectral device configured to direct a selected fraction of light onto a cold detector; a system of cold apertures and shields positioned along the beam path to prevent unwanted thermal radiation from arriving at the cold monochromator and/or the detector; a plurality of optical, IR and microwave filters positioned along the beam path and configured to adjust a spectral composition of light incident upon the sample under investigation and/or on the detector; a refrigerator configured to maintain the detector at a temperature below 1.0K; and an enclosure configured to: thermally insulate the light source, the plurality of mirrors, the sample holder, the cold monochromator and the refrigerator.

  8. X-Ray Interactions with Matter from the Center for X-Ray Optics (CXRO)

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

    Henke, B. L.; Gullikson, E. M.; Davis, J. C.

    The primary interactions of low-energy x-rays within condensed matter, viz. photoabsorption and coherent scattering, are described for photon energies outside the absorption threshold regions by using atomic scattering factors. The atomic scattering factors may be accurately determined from the atomic photoabsorption cross sections using modified Kramers-Kronig dispersion relations. From a synthesis of the currently available experimental data and recent theoretical calculations for photoabsorption, the angle-independent, forward-scattering components of the atomic scattering factors have been thus semiempirically determined and tabulated here for 92 elements and for the region 50-30,000 eV. Atomic scattering factors for all angles of coherent scattering and at the higher photon energies are obtained from these tabulated forward-scattering values by adding a simple angle-dependent form-factor correction. The incoherent scattering contributions that become significant for the light elements at the higher photon energies are similarly determined. The basic x-ray interaction relations that are used in applied x-ray physics are presented here in terms of the atomic scattering factors. The bulk optical constants are also related to the atomic scattering factors. These atomic and optical relations are applied to the detailed calculation of the reflectivity characteristics of a series of practical x-ray mirror, multilayer, and crystal monochromators. Comparisons of the results of this semiempirical,"atom-like", description of x-ray interactions for the low-energy region with those of experiment and ab initio theory are presented.

  9. Interferometric source of multi-color, multi-beam entangled photons with mirror and mixer

    DOE Patents [OSTI]

    Dress, William B.; Kisner, Roger A.; Richards, Roger K.

    2004-06-01

    53 Systems and methods are described for an interferometric source of multi-color, multi-beam entangled photons. An apparatus includes: a multi-refringent device optically coupled to a source of coherent energy, the multi-refringent device providing a beam of multi-color entangled photons; a condenser device optically coupled to the multi-refringent device, the condenser device i) including a mirror and a mixer and ii) converging two spatially resolved portions of the beam of multi-color entangled photons into a converged multi-color entangled photon beam; a tunable phase adjuster optically coupled to the condenser device, the tunable phase adjuster changing a phase of at least a portion of the converged multi-color entangled photon beam to generate a first interferometeric multi-color entangled photon beam; and a beam splitter optically coupled to the condenser device, the beam splitter combining the first interferometeric multi-color entangled photon beam with a second interferometric multi-color entangled photon beam.

  10. APS Organization Chart | Advanced Photon Source

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

    APS Organization Chart The Advanced Photon Source (APS) organization comprises three divisions and one project office. Advanced Photon Source Organization Photon Sciences Overview...

  11. Photonic surfaces for designable nonlinear power shaping

    SciTech Connect (OSTI)

    Biswas, Roshni Povinelli, Michelle L.

    2015-02-09

    We propose a method for designing nonlinear input-output power response based on absorptive resonances of nanostructured surfaces. We show that various power transmission trends can be obtained by placing a photonic resonance mode at the appropriate detuning from the laser wavelength. We demonstrate our results in a silicon photonic crystal slab at a laser wavelength of 808 nm. We quantify the overall spectral red shift as a function of laser power. The shift results from absorptive heating and the thermo-optic effect. We then demonstrate devices with increasing, decreasing, and non-monotonic transmission as a function of laser power. The transmission changes are up to 7.5 times larger than in unpatterned silicon. The strong nonlinear transmission is due to a combination of resonantly enhanced absorption, reduced thermal conductivity, and the resonant transmission lineshape. Our results illustrate the possibility of designing different nonlinear power trends within a single materials platform at a given wavelength of interest.

  12. Design of the First Infrared Beamline at the Siam Photon Laboratory

    SciTech Connect (OSTI)

    Pattanasiriwisawa, W.; Songsiriritthigul, P.; Dumas, P.

    2010-06-23

    This report presents the optical design and optical simulations for the first infrared beamline at the Siam Photon Laboratory. The beamline collects the edge radiation and bending magnet radiation, producing from the BM4 bending magnet of the 1.2 GeV storage ring of the Siam Photon Source. The optical design is optimized for the far- to mid-infrared spectral range (4000-100 cm{sup -1}) for microspectroscopic applications. The optical performance has been examined by computer simulations.

  13. Sunlight Photonics | Open Energy Information

    Open Energy Info (EERE)

    Photonics Place: South Plainfield, New Jersey Zip: 7080 Product: New Jersey-based stealth thin-film PV maker. References: Sunlight Photonics1 This article is a stub. You can help...

  14. Advanced Photon Source Upgrade Project

    ScienceCinema (OSTI)

    Mitchell, John; Gibson, Murray; Young, Linda; Joachimiak, Andrzej

    2013-04-19

    Upgrade to Advanced Photon Source announced by Department Of Energy. Read more: http://go.usa.gov/ivZ

  15. Nanowire photonic crystal waveguides for single-atom trapping and strong light-matter interactions

    SciTech Connect (OSTI)

    Yu, S.-P.; Hood, J. D.; Muniz, J. A.; Martin, M. J.; Hung, C.-L.; Kimble, H. J.; Norte, Richard; Meenehan, Sen M.; Cohen, Justin D.; Painter, Oskar

    2014-03-17

    We present a comprehensive study of dispersion-engineered nanowire photonic crystal waveguides suitable for experiments in quantum optics and atomic physics with optically trapped atoms. Detailed design methodology and specifications are provided, as are the processing steps used to create silicon nitride waveguides of low optical loss in the near-IR. Measurements of the waveguide optical properties and power-handling capability are also presented.

  16. Two-photon spectroscopy of excitons with entangled photons

    SciTech Connect (OSTI)

    Schlawin, Frank, E-mail: Frank.Schlawin@physik.uni-freiburg.de [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States) [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States); Physikalisches Institut, Albert-Ludwigs-Universitt Freiburg, Hermann-Herder-Strae 3, 79108 Freiburg (Germany); Mukamel, Shaul, E-mail: smukamel@uci.edu [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States)] [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States)

    2013-12-28

    The utility of quantum light as a spectroscopic tool is demonstrated for frequency-dispersed pump-probe, integrated pump-probe, and two-photon fluorescence signals which show Ramsey fringes. Simulations of the frequency-dispersed transmission of a broadband pulse of entangled photons interacting with a three-level model of matter reveal how the non-classical time-bandwidth properties of entangled photons can be used to disentangle congested spectra, and reveal otherwise unresolved features. Quantum light effects are most pronounced at weak intensities when entangled photon pairs are well separated, and are gradually diminished at higher intensities when different photon pairs overlap.

  17. Enhancement of second harmonic generation in NaNO{sub 2}-infiltrated opal photonic crystal using structural light focusing

    SciTech Connect (OSTI)

    Zaytsev, Kirill I. Yurchenko, Stanislav O.

    2014-08-04

    Experimental and numerical results for second harmonic generation (SHG) in photonic crystal (PC) based on NaNO{sub 2}-infiltrated opal matrix are presented. SHG is performed in reflection mode; thus, the direction of the SHG maximum is equal to the angle of mirror reflection. The PC was pumped with femtosecond optical pulses at different angles of incidence, allowing the dependence of the SHG efficiency on the location of the fundamental wavelength toward the PC band gap (BG) to be examined. The most efficient SHG was observed when pumping the BG of the PC. To interpret the experimental results, finite-difference time-domain numerical simulations of the light interaction with the PC were conducted. The observed effect of highly efficient SHG is associated with structural light focusing, and, as a consequence, with strong optical field localization within certain near-surface PC regions. Thus, SHG enhancement based on structural light focusing in PC was demonstrated.

  18. Transversely stable soliton trains in photonic lattices

    SciTech Connect (OSTI)

    Yang Jianke

    2011-09-15

    We report the existence of transversely stable soliton trains in optics. These stable soliton trains are found in two-dimensional square photonic lattices when they bifurcate from X-symmetry points with saddle-shaped diffraction inside the first Bloch band and their amplitudes are above a certain threshold. We also show that soliton trains with low amplitudes or bifurcated from edges of the first Bloch band ({Gamma} and M points) still suffer transverse instability. These results are obtained in the continuous lattice model and are further corroborated by the discrete model.

  19. Optical modulator including grapene

    DOE Patents [OSTI]

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  20. In-plane emission of indistinguishable photons generated by an integrated quantum emitter

    SciTech Connect (OSTI)

    Kalliakos, Sokratis Bennett, Anthony J.; Ward, Martin B.; Ellis, David J. P.; Skiba-Szymanska, Joanna; Shields, Andrew J.; Brody, Yarden; Schwagmann, Andre; Farrer, Ian; Griffiths, Jonathan P.; Jones, Geb A. C.; Ritchie, David A.

    2014-06-02

    We demonstrate the emission of indistinguishable photons along a semiconductor chip originating from carrier recombination in an InAs quantum dot. The emitter is integrated in the waveguiding region of a photonic crystal structure, allowing for on-chip light propagation. We perform a Hong-Ou-Mandel-type of experiment with photons collected from the exit of the waveguide, and we observe two-photon interference under continuous wave excitation. Our results pave the way for the integration of quantum emitters in advanced photonic quantum circuits.

  1. Photon-counting solid-state photomultiplier

    SciTech Connect (OSTI)

    Petroff, M.D.; Stapelbroek, M.G.

    1989-02-01

    The Solid-State Photomultiplier is a silicon device capable of continuous detection of individual photons in the wave length range from 0.4 to 28 ..mu..m. Operated with an applied bias near 7 volts the device responds to the absorption of an incident photon with a submicrosecond-rise-time current pulse with a narrow amplitude distribution well above the electronic readout noise level. Optimal photon-counting performance occurs between 6 and 10 K and for count rates less than 10/sup 10/ counts/s per cm/sup 2/ of detector area. A 60% counting quantum efficiency has been demonstrated at 20 ..mu..m, and near 60% was observed in the visible light region. The underlying mechanism involves extremely fast internal charge amplification by impact ionization of impurity-band electrons and results in a pulse for each photoelectrically or thermally induced free carrier. The thermally induced dark pulse rate at 7 K is sufficiently low that background limited detector performance is obtained at a background of less than 10/sup 6/ photons/cm/sup 2/s.

  2. Photons & Fusion Newsletter

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

    1 / december Photons & Fusion Newsletter December 2011 MIT Plasma Science Lab Develops NIF Diagnostics A typical NIF experiment is over in a few billionths of a second. Obtaining meaningful information about what occurs during this extremely brief time period, in and around a tiny target, has required the design and development of a new breed of detectors, cameras, and other diagnostic instruments, many of which have been created through partnerships with universities and national

  3. Photonic Crystals for Enhancing Thermophotovoltaic Energy Conversion

    SciTech Connect (OSTI)

    LIN, SHAWN-YU; FLEMING, JAMES G.; MORENO, JOSEPH A.

    2003-03-01

    Thermophotovoltaics (TPV) converts the radiant energy of a thermal source into electrical energy using photovoltaic cells. TPV has a number of attractive features, including: fuel versatility (nuclear, fossil, solar, etc.), quiet operation, low maintenance, low emissions, light weight, high power density, modularity, and possibility for cogeneration of heat and electricity. Some of these features are highly attractive for military applications (Navy and Army). TPV could also be used for distributed power and automotive applications wherever fuel cells, microturbines, or cogeneration are presently being considered if the efficiencies could be raised to around 30%. This proposal primarily examine approaches to improving the radiative efficiency. The ideal irradiance for the PV cell is monochromatic illumination at the bandgap. The photonic crystal approach allows for the tailoring of thermal emission spectral bandwidth at specific wavelengths of interest. The experimental realization of metallic photonic crystal structures, the optical transmission, reflection and absorption characterization of it have all been carried out in detail and will be presented next. Additionally, comprehensive models of TPV conversion has been developed and applied to the metallic photonic crystal system.

  4. Fabrication of Ceramic Layer-by-Layer Infrared Wavelength Photonic Band Gap Crystals

    SciTech Connect (OSTI)

    Henry Hao-Chuan Kang

    2004-12-19

    Photonic band gap (PBG) crystals, also known as photonic crystals, are periodic dielectric structures which form a photonic band gap that prohibit the propagation of electromagnetic (EM) waves of certain frequencies at any incident angles. Photonic crystals have several potential applications including zero-threshold semiconductor lasers, the inhibition of spontaneous emission, dielectric mirrors, and wavelength filters. If defect states are introduced in the crystals, light can be guided from one location to another or even a sharp bending of light in micron scale can be achieved. This generates the potential for optical waveguide and optical circuits, which will contribute to the improvement in the fiber-optic communications and the development of high-speed computers.

  5. Projection optics box

    DOE Patents [OSTI]

    Hale, Layton C.; Malsbury, Terry; Hudyma, Russell M.; Parker, John M.

    2000-01-01

    A projection optics box or assembly for use in an optical assembly, such as in an extreme ultraviolet lithography (EUVL) system using 10-14 nm soft x-ray photons. The projection optics box utilizes a plurality of highly reflective optics or mirrors, each mounted on a precision actuator, and which reflects an optical image, such as from a mask, in the EUVL system onto a point of use, such as a target or silicon wafer, the mask, for example, receiving an optical signal from a source assembly, such as a developed from laser system, via a series of highly reflective mirrors of the EUVL system. The plurality of highly reflective optics or mirrors are mounted in a housing assembly comprised of a series of bulkheads having wall members secured together to form a unit construction of maximum rigidity. Due to the precision actuators, the mirrors must be positioned precisely and remotely in tip, tilt, and piston (three degrees of freedom), while also providing exact constraint.

  6. High-speed photonic modulator designs

    SciTech Connect (OSTI)

    DeRose, Christopher; Zortman, William A

    2015-02-03

    An optical device includes a microdisk optical resonator element. The microdisk resonator element is formed on a substrate and has upper and lower portions respectively distal and proximal the substrate. An arcuate semiconductor contact region partially surrounds the microdisk resonator element. A first modulator electrode is centrally formed on the upper portion of the microdisk resonator element, and a second modulator electrode is formed on the arcuate contact region. A laminar semiconductor region smaller in thickness than the microdisk resonator element separates the arcuate contact region from the microdisk resonator element and is formed on the substrate so as to electrically connect the arcuate contact region to the lower portion of the microdisk resonator element.

  7. Photonic-band-gap effects in two-dimensional polycrystalline and amorphous structures

    SciTech Connect (OSTI)

    Yang, Jin-Kyu; Noh, Heeso; Liew, Seng-Fatt; Schreck, Carl; Guy, Mikhael I.; O'Hern, Corey S.; Cao, Hui

    2010-11-15

    We study numerically the density of optical states (DOS) in two-dimensional photonic structures with short-range positional order and observe a transition from polycrystalline to amorphous photonic systems. In polycrystals, photonic band gaps (PBGs) are formed within individual domains, which leads to a depletion of the DOS similar to that in periodic structures. In amorphous photonic media, the domain sizes are too small to form PBGs, thus the depletion of the DOS is weakened significantly. The critical domain size that separates the polycrystalline and amorphous regimes is determined by the attenuation length of Bragg scattering, which depends not only on the degree of positional order but also the refractive-index contrast of the photonic material. Even with relatively low-refractive-index contrast, we find that modest short-range positional order in photonic structures enhances light confinement via collective scattering and interference.

  8. Optical induction scheme for assembling nondiffracting aperiodic Vogel spirals

    SciTech Connect (OSTI)

    Diebel, Falko Rose, Patrick; Boguslawski, Martin; Denz, Cornelia

    2014-05-12

    We introduce an experimental approach to realize aperiodic photonic lattices based on multiplexing of nondiffracting Bessel beams. This holographic optical induction scheme takes advantage of the well localized Bessel beam as a basis to assemble two-dimensional photonic lattices. We present the realization of an optically induced two-dimensional golden-angle Vogel spiral lattice, which belongs to the family of deterministic aperiodic structures. With our technique, a very broad class of photonic refractive index landscapes now becomes accessible to optical induction, which could not be realized with established distributed holographic techniques.

  9. Optical Square-Wave Clock Generation Based on an All-Optical Flip-Flop

    SciTech Connect (OSTI)

    Kaplan, A.M.; Agrawal, G.P.; Maywar, D.N.

    2010-03-10

    We demonstrate optical square-wave clock generation based on an all-optical flip-flop. The bistable output power from a resonant-type semiconductor optical amplifier (SOA) is switched ON and OFF by modulating its input with its output via cross-gain modulation in a traveling-wave SOA. All active components are driven by dc currents, and the wavelength and clock frequency are selectable. A clock frequency of 3.5 MHz is demonstrated, limited by the time of flight between bulk optical components. Optical square-wave clock signals are promising for applications in photonic integrated circuits and all-optical signal processing.

  10. Photon Source Parameters

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

    Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They can be used in a variety

  11. Photon Source Parameters

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

    Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They can be used in a variety

  12. Photon Source Parameters

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

    Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They can be used in a variety

  13. Photon Source Parameters

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

    Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They can be used in a variety

  14. Photon Source Parameters

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

    Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They can be used in a variety

  15. Photon Source Parameters

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

    Photon Source Parameters Print Summary Graph of Brightness Curves for All Insertion Devices Insertion Device and Bend Magnet Parameters Bend Magnet Superbend Magnet U30 Undulator U50 Undulator U80 Undulator U100 Undulator W114 Wiggler The ALS has six elliptically polarizing undulators, two in straight 4, two in straight 11, and one each in straights 6 and 7. All are arranged with chicanes so that two such devices can be installed to feed two independent beamlines. They can be used in a variety

  16. Media Center | Advanced Photon Source

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

    distributed to all APS users and others interested in the APS. Research Highlights Books Articles on Advanced Photon Source research and engineering highlights that are written...

  17. Lightwave Photonics | Open Energy Information

    Open Energy Info (EERE)

    Lightwave Photonics Place: Encinitas, California Zip: 92024 Product: California-based LED chip manufacturer startup. Coordinates: 33.045436, -117.292518 Show Map Loading...

  18. APS Science | Advanced Photon Source

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

    Science APS Science features articles on Advanced Photon Source research and engineering highlights that are written for the interested public as well as the synchrotron x-ray,...

  19. Video Library | Advanced Photon Source

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

    Archives APS Brochure Annual Reports Posters Podcasts Image Gallery external site Video Library Syndicated Feeds (RSS) Featured Videos: Introduction to the Advanced Photon...

  20. Video Library | Advanced Photon Source

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

    Archives APS Brochure Annual Reports Posters Podcasts Image Gallery external site Video Library Syndicated Feeds (RSS) Now Playing: The Advanced Photon Source More videos:...

  1. Video Library | Advanced Photon Source

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

    Video Library Related Links: APS Colloquium APS Podcasts APS Today More videos: Introduction to the APS Physics of the Blues Now Playing: Building the Advanced Photon Source This...

  2. Two photon spectroscopy of UF6 in the near ultraviolet

    SciTech Connect (OSTI)

    Bernstein, E.R.; Kennedy, P.M.

    1981-03-01

    The two photon excited fluorescence excitation spectrum of UF6 was observed in the region 410 to 315 nm. The spectrum was virtually indistinguishable from the one photon absorption in this region. No vibronic structure was observed in absorption or dispersed emission. These data indicate a high density of u and g states for UF6 in this energy range and facile photochemical decomposition. Emission intensity was found to be proportional to laser power to the 3.0 to 3.6 power.

  3. Polarization observables from the photoproduction of omega-mesons using linearly polarized photons

    SciTech Connect (OSTI)

    D. Martinez, P.L. Cole, CLAS Collaboration

    2012-04-01

    We report on the photon beam asymmetry, {Sigma}, of the {omega} meson decaying into {pi}{sup +}, {pi}{sup -}, {pi}{sup 0} using a beam of linearly polarized photons in the photon energy region of E{sub {gamma}} = 1.9 GeV. These preliminary results are from the summer 2005 g8b dataset, which were collected with the CLAS detector in Hall B of Jefferson Lab.

  4. Gated frequency-resolved optical imaging with an optical parametric amplifier

    DOE Patents [OSTI]

    Cameron, S.M.; Bliss, D.E.; Kimmel, M.W.; Neal, D.R.

    1999-08-10

    A system for detecting objects in a turbid media utilizes an optical parametric amplifier as an amplifying gate for received light from the media. An optical gating pulse from a second parametric amplifier permits the system to respond to and amplify only ballistic photons from the object in the media. 13 figs.

  5. Gated frequency-resolved optical imaging with an optical parametric amplifier

    DOE Patents [OSTI]

    Cameron, Stewart M.; Bliss, David E.; Kimmel, Mark W.; Neal, Daniel R.

    1999-01-01

    A system for detecting objects in a turbid media utilizes an optical parametric amplifier as an amplifying gate for received light from the media. An optical gating pulse from a second parametric amplifier permits the system to respond to and amplify only ballistic photons from the object in the media.

  6. Polarization and spectral characteristics of the two-photon luminescence from colloidal gold nanoparticles excited by tunable laser radiation

    SciTech Connect (OSTI)

    Yashunin, D. A. Korytin, A. I.; Stepanov, A. N.

    2015-12-15

    We have experimentally studied two-photon luminescence from a colloidal solution of spherical gold nanoparticles by tuning the wavelength of the exciting radiation. The measured polarization and spectral characteristics of the two-photon luminescence signal show that the observed nonlinear optical response is determined by the dimers present in the solution with a concentration of a few percent of total nanoparticle number.

  7. Photonic polymer-blend structures and method for making

    DOE Patents [OSTI]

    Barnes, Michael D.

    2004-06-29

    The present invention comprises the formation of photonic polymer-blend structures having tunable optical and mechanical properties. The photonic polymer-blend structures comprise monomer units of spherical microparticles of a polymer-blend material wherein the spherical microparticles have surfaces partially merged with one another in a robust inter-particle bond having a tunable inter-particle separation or bond length sequentially attached in a desired and programmable architecture. The photonic polymer-blend structures of the present invention can be linked by several hundred individual particles sequentially linked to form complex three-dimensional structures or highly ordered two-dimensional arrays of 3D columns with 2D spacing.

  8. Final Optics

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

    final optics Final Optics Schematic layout of NIF's final optics assembly (FOA). The suite of optics for one beamline is on the right. 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 integrated optics modules (IOMs) that incorporate beam conditioning, frequency conversion, focusing, diagnostic sampling, and debris shielding capabilities into a single compact assembly. These optics are shown in the

  9. Method of photon spectral analysis

    DOE Patents [OSTI]

    Gehrke, R.J.; Putnam, M.H.; Killian, E.W.; Helmer, R.G.; Kynaston, R.L.; Goodwin, S.G.; Johnson, L.O.

    1993-04-27

    A spectroscopic method to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium and [gamma]-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type germanium spectrometer which is equally efficient for the detection of low-energy x-rays (10-2,000 keV), as well as high-energy [gamma] rays (>1 MeV). A 8,192- or 16,384 channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, and detector resolution. The L x-ray portion of each spectrum is analyzed by a linear-least-squares spectral fitting technique. The [gamma]-ray portion of each spectrum is analyzed by a standard Ge [gamma]-ray analysis program. This method can be applied to any analysis involving x- and [gamma]-ray analysis in one spectrum and is especially useful when interferences in the x-ray region can be identified from the [gamma]-ray analysis and accommodated during the x-ray analysis.

  10. Method of photon spectral analysis

    DOE Patents [OSTI]

    Gehrke, Robert J.; Putnam, Marie H.; Killian, E. Wayne; Helmer, Richard G.; Kynaston, Ronnie L.; Goodwin, Scott G.; Johnson, Larry O.

    1993-01-01

    A spectroscopic method to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium and .gamma.-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type germanium spectrometer which is equally efficient for the detection of low-energy x-rays (10-2000 keV), as well as high-energy .gamma. rays (>1 MeV). A 8192- or 16,384 channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, and detector resolution. The L x-ray portion of each spectrum is analyzed by a linear-least-squares spectral fitting technique. The .gamma.-ray portion of each spectrum is analyzed by a standard Ge .gamma.-ray analysis program. This method can be applied to any analysis involving x- and .gamma.-ray analysis in one spectrum and is especially useful when interferences in the x-ray region can be identified from the .gamma.-ray analysis and accommodated during the x-ray analysis.

  11. The SIAM Photon Source

    SciTech Connect (OSTI)

    Pairsuwan, Weerapong

    2007-01-19

    A short history of the SIAM Photon Source in Thailand is described. The facility is based on the 1 GeV storage ring obtained from the SORTEC consortium in Japan. After a redesign to include insertion straight sections it produced the first light in December 2001 and the first beam line became operational in early 2002. Special difficulties appear when a synchrotron light facility is obtained by donation, which have mostly to do with the absence of human resource development that elsewhere is commonly accomplished during design and construction. Additional problems arise by the distance of a developing country like Thailand from the origin of technical parts of the donation. A donation does not provide time to generate local capabilities or include in the technical design locally obtainable parts. This makes future developments, repairs and maintenance more time consuming, difficult and expensive than it should be. In other cases, parts of components are proprietary or obsolete or both which requires redesign and engineering at a time when the replacement part should be available to prevent stoppage of operation.The build-up of a user community is very difficult, especially when the radiation spectrum is confined to the VUV regime. Most of scientific interest these days is focused on the x-ray regime. Due to its low beam energy, the SIAM storage ring did not produce useful x-ray intensities and we are therefore in the midst of an upgrade to produce harder radiation. The first step has been achieved with a 20% increase of energy to 1.2 GeV. This step shifts the critical photon energy of bending magnet radiation from 800 eV to 1.4 keV providing useful radiation up to 7 keV. A XAS-beam line has been completed in 2005 and experimentation is very active by now. The next step is to install a 6.4 T wavelength shifter by the end of 2006 resulting in a critical photon energy of 6.15 keV. Further upgrades are planed for the comming years.

  12. Optical set-reset latch

    DOE Patents [OSTI]

    Skogen, Erik J.

    2013-01-29

    An optical set-reset (SR) latch is formed from a first electroabsorption modulator (EAM), a second EAM and a waveguide photodetector (PD) which are arranged in an optical and electrical feedback loop which controls the transmission of light through the first EAM to latch the first EAM in a light-transmissive state in response to a Set light input. A second waveguide PD controls the transmission of light through the second EAM and is used to switch the first EAM to a light-absorptive state in response to a Reset light input provided to the second waveguide PD. The optical SR latch, which may be formed on a III-V compound semiconductor substrate (e.g. an InP or a GaAs substrate) as a photonic integrated circuit (PIC), stores a bit of optical information and has an optical output for the logic state of that bit of information.

  13. Sub-picosecond optical switching with a negative index metamaterial...

    Office of Scientific and Technical Information (OSTI)

    This has the potential for Tbs aU-optical communication and will lead to other novel, compact, tunable sub-picosecond (ps) photonic devices. Authors: Dani, Keshav M 1 ; Upadhya, ...

  14. Transpiration purged optical probe

    DOE Patents [OSTI]

    2004-01-06

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

  15. Collimator-free photon tomography

    DOE Patents [OSTI]

    Dilmanian, F. Avraham; Barbour, Randall L.

    1998-10-06

    A method of uncollimated single photon emission computed tomography includes administering a radioisotope to a patient for producing gamma ray photons from a source inside the patient. Emissivity of the photons is measured externally of the patient with an uncollimated gamma camera at a plurality of measurement positions surrounding the patient for obtaining corresponding energy spectrums thereat. Photon emissivity at the plurality of measurement positions is predicted using an initial prediction of an image of the source. The predicted and measured photon emissivities are compared to obtain differences therebetween. Prediction and comparison is iterated by updating the image prediction until the differences are below a threshold for obtaining a final prediction of the source image.

  16. Collimator-free photon tomography

    DOE Patents [OSTI]

    Dilmanian, F.A.; Barbour, R.L.

    1998-10-06

    A method of uncollimated single photon emission computed tomography includes administering a radioisotope to a patient for producing gamma ray photons from a source inside the patient. Emissivity of the photons is measured externally of the patient with an uncollimated gamma camera at a plurality of measurement positions surrounding the patient for obtaining corresponding energy spectrums thereat. Photon emissivity at the plurality of measurement positions is predicted using an initial prediction of an image of the source. The predicted and measured photon emissivities are compared to obtain differences therebetween. Prediction and comparison is iterated by updating the image prediction until the differences are below a threshold for obtaining a final prediction of the source image. 6 figs.

  17. Photon detectors with gaseous amplification

    SciTech Connect (OSTI)

    Va`vra, J.

    1996-08-01

    Gaseous photon detectors, including very large 4{pi}-devices such as those incorporated in SLD and DELPHI, are finally delivering physics after many years of hard work. Photon detectors are among the most difficult devices used in physics experiments, because they must achieve high efficiency for photon transport and for the detection of single photoelectrons. Among detector builders, there is hardly anybody who did not make mistakes in this area, and who does not have a healthy respect for the problems involved. This point is stressed in this paper, and it is suggested that only a very small operating phase space is available for running gaseous photon detectors in a very large system with good efficiency and few problems. In this paper the authors discuss what was done correctly or incorrectly in first generation photon detectors, and what would be their recommendations for second generation detectors. 56 refs., 11 figs.

  18. Photon enhanced thermionic emission

    DOE Patents [OSTI]

    Schwede, Jared; Melosh, Nicholas; Shen, Zhixun

    2014-10-07

    Photon Enhanced Thermionic Emission (PETE) is exploited to provide improved efficiency for radiant energy conversion. A hot (greater than 200.degree. C.) semiconductor cathode is illuminated such that it emits electrons. Because the cathode is hot, significantly more electrons are emitted than would be emitted from a room temperature (or colder) cathode under the same illumination conditions. As a result of this increased electron emission, the energy conversion efficiency can be significantly increased relative to a conventional photovoltaic device. In PETE, the cathode electrons can be (and typically are) thermalized with respect to the cathode. As a result, PETE does not rely on emission of non-thermalized electrons, and is significantly easier to implement than hot-carrier emission approaches.

  19. Tapered fiber coupling of single photons emitted by a deterministically positioned single nitrogen vacancy center

    SciTech Connect (OSTI)

    Liebermeister, Lars Petersen, Fabian; Münchow, Asmus v.; Burchardt, Daniel; Hermelbracht, Juliane; Tashima, Toshiyuki; Schell, Andreas W.; Benson, Oliver; Meinhardt, Thomas; Krueger, Anke; Stiebeiner, Ariane; Rauschenbeutel, Arno; Weinfurter, Harald; Weber, Markus

    2014-01-20

    A diamond nano-crystal hosting a single nitrogen vacancy (NV) center is optically selected with a confocal scanning microscope and positioned deterministically onto the subwavelength-diameter waist of a tapered optical fiber (TOF) with the help of an atomic force microscope. Based on this nano-manipulation technique, we experimentally demonstrate the evanescent coupling of single fluorescence photons emitted by a single NV-center to the guided mode of the TOF. By comparing photon count rates of the fiber-guided and the free-space modes and with the help of numerical finite-difference time domain simulations, we determine a lower and upper bound for the coupling efficiency of (9.5 ± 0.6)% and (10.4 ± 0.7)%, respectively. Our results are a promising starting point for future integration of single photon sources into photonic quantum networks and applications in quantum information science.

  20. Method and apparatus for producing laser radiation following two-photon excitation of a gaseous medium

    DOE Patents [OSTI]

    Bischel, William K. [Menlo Park, CA; Jacobs, Ralph R. [Livermore, CA; Prosnitz, Donald [Hamden, CT; Rhodes, Charles K. [Palo Alto, CA; Kelly, Patrick J. [Fort Lewis, WA

    1979-02-20

    Method and apparatus for producing laser radiation by two-photon optical pumping of an atomic or molecular gaseous medium and subsequent lasing action. A population inversion is created as a result of two-photon absorption of the gaseous species. Stark tuning is utilized, if necessary, in order to tune the two-photon transition into exact resonance. In particular, gaseous ammonia (NH.sub.3) or methyl fluoride (CH.sub.3 F) is optically pumped by a pair of CO.sub.2 lasers to create a population inversion resulting from simultaneous two-photon excitation of a high-lying vibrational state, and laser radiation is produced by stimulated emission of coherent radiation from the inverted level.

  1. Method and apparatus for producing laser radiation following two-photon excitation of a gaseous medium

    DOE Patents [OSTI]

    Bischel, W.K.; Jacobs, R.R.; Prosnitz, D.P.; Rhodes, C.K.; Kelly, P.J.

    1979-02-20

    Method and apparatus are disclosed for producing laser radiation by two-photon optical pumping of an atomic or molecular gaseous medium and subsequent lasing action. A population inversion is created as a result of two-photon absorption of the gaseous species. Stark tuning is utilized, if necessary, in order to tune the two-photon transition into exact resonance. In particular, gaseous ammonia (NH[sub 3]) or methyl fluoride (CH[sub 3]F) is optically pumped by a pair of CO[sub 2] lasers to create a population inversion resulting from simultaneous two-photon excitation of a high-lying vibrational state, and laser radiation is produced by stimulated emission of coherent radiation from the inverted level. 3 figs.

  2. A highly conspicuous mineralized composite photonic architecture...

    Office of Scientific and Technical Information (OSTI)

    A highly conspicuous mineralized composite photonic architecture in the translucent shell of the blue-rayed limpet Title: A highly conspicuous mineralized composite photonic ...

  3. Photonic Metamaterials, Nano- plasmonics and Superlens | MIT...

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

    nano-scale science and technology, meta- materials, nano-photonics and bio-technologies. ... Bulletin (Materials Research Society), Photonics Spectra, Materials Today, Physics Web, ...

  4. Advanced Solar Photonics | Open Energy Information

    Open Energy Info (EERE)

    Advanced Solar Photonics Place: Lake Mary, Florida Zip: 32746 Product: Florida-based thin film PV module manufacturer. References: Advanced Solar Photonics1 This article is...

  5. Higher-order photon correlations in pulsed photonic crystal nanolasers

    SciTech Connect (OSTI)

    Elvira, D.; Hachair, X.; Braive, R.; Beaudoin, G.; Robert-Philip, I.; Sagnes, I.; Abram, I.; Beveratos, A.; Verma, V. B.; Baek, B.; Nam, S. W.; Stevens, M. J.; Dauler, E. A.

    2011-12-15

    We report on the higher-order photon correlations of a high-{beta} nanolaser under pulsed excitation at room temperature. Using a multiplexed four-element superconducting single-photon detector we measured g{sup (n)}(0-vector) with n=2,3,4. All orders of correlation display partially chaotic statistics, even at four times the threshold excitation power. We show that this departure from coherence and Poisson statistics is due to the quantum fluctuations associated with the small number of photons at the lasing threshold.

  6. Electron Photon Interaction Cross Sections

    Energy Science and Technology Software Center (OSTI)

    2014-11-01

    Version 00 The Electron Photon Interaction Cross Sections, EPICS, provides the atomic data needed to perform coupled Electron-Photon transport calculations, to produce accurate macroscopic results, such as energy deposit and dose. Atomic data is provided for elements, Z = 1 to 100, over the energy range 10 eV to 100 GeV; note that nuclear data, such as photo-nuclear, and data for compounds, are not included. All data is in a simple computer independent text formatmore » that is standard and presented to a high precision that can be easily read by computer codes written in any computer language, e.g., C, C++, and FORTRAN. EPICS includes four separate data bases that are designed to be used in combination, these include, • The Evaluated Electron Data Library (EEDL), to describe the interaction of electrons with matter. • The Evaluated Photon Data Library (EPDL), to describe the interaction of photons with matter. • The Evaluated Atomic Data Library (EADL), to describe the emission of electrons and photons back to neutrality following an ionizing event, caused by either electron or photon interactions. • The Evaluated Excitation Data Library (EXDL), to describe the excitation of atoms due to photon interaction. All of these are available in the Extended ENDL format (ENDLX) in which the evaluations were originally performed. The first three are also available in the ENDF format; as yet ENDF does not include formats to handle excitation data (EXDL).« less

  7. Quantitative analysis of directional spontaneous emission spectra from light sources in photonic crystals

    SciTech Connect (OSTI)

    Nikolaev, Ivan S.; Lodahl, Peter; Vos, Willem L.

    2005-05-15

    We have performed angle-resolved measurements of spontaneous-emission spectra from laser dyes and quantum dots in opal and inverse opal photonic crystals. Pronounced directional dependencies of the emission spectra are observed: angular ranges of strongly reduced emission adjoin with angular ranges of enhanced emission. It appears that emission from embedded light sources is affected both by the periodicity and by the structural imperfections of the crystals: the photons are Bragg diffracted by lattice planes and scattered by unavoidable structural disorder. Using a model comprising diffuse light transport and photonic band structure, we quantitatively explain the directional emission spectra. This work provides detailed understanding of the transport of spontaneously emitted light in real photonic crystals, which is essential in the interpretation of quantum optics in photonic-band-gap crystals and for applications wherein directional emission and total emission power are controlled.

  8. Multi-bit quantum random number generation by measuring positions of arrival photons

    SciTech Connect (OSTI)

    Yan, Qiurong; Zhao, Baosheng; Liao, Qinghong; Zhou, Nanrun

    2014-10-15

    We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator.

  9. Quantum Optics

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

    Energy Frontier Research Centers: Solid-State Lighting Science Center for Frontiers of ... Quantum Optics HomeEnergy ResearchEFRCsSolid-State Lighting Science EFRCQuantum Optics ...

  10. Summary of Lepton Photon 2011

    SciTech Connect (OSTI)

    Peskin, Michael E.; /SLAC

    2012-03-14

    In this lecture, I summarize developments presented at the Lepton Photon 2011 conference and give my perspective on the current situation in high-energy physics. I am grateful to the organizers of Lepton Photon 2011 for providing us a very pleasant and simulating week in Mumbai. This year's Lepton Photon conference has covered the full range of subjects that fall within the scope of high-energy physics, including connections to cosmology, nuclear physics, and atomic physics. The experiments that were discussed detect particles ranging in energy from radio frequencies to EeV.

  11. Manufacturing method of photonic crystal

    DOE Patents [OSTI]

    Park, In Sung; Lee, Tae Ho; Ahn, Jin Ho; Biswas, Rana; Constant, Kristen P.; Ho, Kai-Ming; Lee, Jae-Hwang

    2013-01-29

    A manufacturing method of a photonic crystal is provided. In the method, a high-refractive-index material is conformally deposited on an exposed portion of a periodic template composed of a low-refractive-index material by an atomic layer deposition process so that a difference in refractive indices or dielectric constants between the template and adjacent air becomes greater, which makes it possible to form a three-dimensional photonic crystal having a superior photonic bandgap. Herein, the three-dimensional structure may be prepared by a layer-by-layer method.

  12. Photoluminescence of ZnO infiltrated into a three-dimensional photonic crystal

    SciTech Connect (OSTI)

    Gruzintsev, A. N. Emelchenko, G. A.; Masalov, V. M.

    2009-08-15

    The effect of the photonic band gap (stopband) of the photonic crystal, the synthesized SiO{sub 2} opal with embedded zinc oxide, on its luminescence in the violet spectral region is studied. It is shown that the position of the photonic band gap in the luminescence and reflectance spectra of the infiltrated opal depends on the diameter of the constituent nanoglobules, the volume fraction of zinc oxide, and on the signal's acceptance angle. It is found that, for the ZnO-opal nanocomposites, the emission intensity is decreased and the luminescence decay time is increased in the spatial directions, in which the photonic band gap coincides in spectral position with the luminescence peak of zinc oxide. The change in the decay time can be attributed to the change in the local density of photonic states in the photonic band gap.

  13. Apodized structures for the integration of defect sites into photonic lattices

    SciTech Connect (OSTI)

    Boguslawski, Martin Kelberer, Andreas; Rose, Patrick; Denz, Cornelia

    2014-09-15

    We introduce a versatile concept to optically induce photonic structures of local refractive index modulations as well as photonic lattices holding single defect sites. For a given structure, we develop a set of nondiffracting beams obtained by fractionalizing the corresponding spatial spectrum. By combining this set in a multiplexing procedure, we achieve an incoherent combination of all individual structures of the set resulting in a locally addressable refractive index manipulation. We exemplarily present experimental results for apodized, meaning locally confined index changes in a photorefractive crystal resembling a sixfold and a circular symmetric structure. By an additional multiplexing step, we furthermore create periodic photonic lattices featuring embedded defects.

  14. THE PHOTON UNDERPRODUCTION CRISIS

    SciTech Connect (OSTI)

    Kollmeier, Juna A.; Weinberg, David H.; McEwen, Joseph; Oppenheimer, Benjamin D.; Danforth, Charles; Haardt, Francesco; Katz, Neal; Fardal, Mark; Davé, Romeel; Madau, Piero; Ford, Amanda B.; Peeples, Molly S.

    2014-07-10

    We examine the statistics of the low-redshift Lyα forest from smoothed particle hydrodynamic simulations in light of recent improvements in the estimated evolution of the cosmic ultraviolet background (UVB) and recent observations from the Cosmic Origins Spectrograph (COS). We find that the value of the metagalactic photoionization rate (Γ{sub HI}) required by our simulations to match the observed properties of the low-redshift Lyα forest is a factor of five larger than the value predicted by state-of-the art models for the evolution of this quantity. This mismatch in Γ{sub HI} results in the mean flux decrement of the Lyα forest being overpredicted by at least a factor of two (a 10σ discrepancy with observations) and a column density distribution of Lyα forest absorbers systematically and significantly elevated compared to observations over nearly two decades in column density. We examine potential resolutions to this mismatch and find that either conventional sources of ionizing photons (galaxies and quasars) must contribute considerably more than current observational estimates or our theoretical understanding of the low-redshift universe is in need of substantial revision.

  15. Magnetic Materials | Advanced Photon Source

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

    Materials Internal Magnetic Materials The Magnetic Material Group (MMG) is part of the X-ray Science Division (XSD) at the Advanced Photon Source (APS). Our research focuses on the...

  16. APS Podcasts | Advanced Photon Source

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

    of Art Preservation and Connoisseurship August 14, 2007; mp3 - 1.88MB Franceska Casadio, Art Institute of Chicago: November 3, 2004 The Advanced Photon Source (videomp4) August...

  17. Photonic Systems | The Ames Laboratory

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

    Photonic Systems Research Personnel Updates Publications Dramatic Efficiency Improvements for Organic Light Emitting Diodes Read More Standing Ribbons on Edge Leads to Transparent Triumph Read More Illuminating the Deep-Blue UV Read More Previous Pause Next Synthesis Since ~1990, the Ames Laboratory has conducted pioneering development and studies of 3D photonic crystals (PCs), developed forefront organic light-emitting diodes (OLEDs) and procedures for characterizing them, and conducted

  18. Ideal solar cell equation in the presence of photon recycling

    SciTech Connect (OSTI)

    Lan, Dongchen Green, Martin A.

    2014-11-07

    Previous derivations of the ideal solar cell equation based on Shockley's p-n junction diode theory implicitly assume negligible effects of photon recycling. This paper derives the equation in the presence of photon recycling that modifies the values of dark saturation and light-generated currents, using an approach applicable to arbitrary three-dimensional geometries with arbitrary doping profile and variable band gap. The work also corrects an error in previous work and proves the validity of the reciprocity theorem for charge collection in such a more general case with the previously neglected junction depletion region included.

  19. R. Tayloe, Indiana University Lepton-Photon '07 1

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

    Lepton-Photon '07 1 Neutrino Oscillation Results from MiniBooNE Outline: - motivation, strategy - experiment - analysis - results - New: further investigations of low-energy region R. Tayloe, Indiana University R. Tayloe, Indiana University Lepton-Photon '07 2 The LSND Result ν e events vs energy The LSND experiment observed an excess ofν e events in beam ofν µ 87.9 ± 22.4 ± 6.0 (4σ) consistent withν µ →ν e oscillations. However, this result, with large ∆m 2 ,does

  20. 1993 CAT workshop on beamline optical designs

    SciTech Connect (OSTI)

    Not Available

    1993-11-01

    An Advanced Photon Source (APS) Collaborative Access Team (CAT) Workshop on Beamline Optical Designs was held at Argonne National Laboratory on July 26--27, 1993. The goal of this workshop was to bring together experts from various synchrotron sources to provide status reports on crystal, reflecting, and polarizing optics as a baseline for discussions of issues facing optical designers for CAT beamlines at the APS. Speakers from the European Synchrotron Radiation Facility (ESRF), the University of Chicago, the National Synchrotron Light Source, and the University of Manchester (England) described single- and double-crystal monochromators, mirrors, glass capillaries, and polarizing optics. Following these presentations, the 90 participants divided into three working groups: Crystal Optics Design, Reflecting Optics, and Optics for Polarization Studies. This volume contains copies of the presentation materials from all speakers, summaries of the three working groups, and a ``catalog`` of various monochromator designs.

  1. Optical microspectrometer

    DOE Patents [OSTI]

    Sweatt, William C.; Christenson, Todd R.

    2004-05-25

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

  2. Use of chemical-mechanical polishing for fabricating photonic bandgap structures

    DOE Patents [OSTI]

    Fleming, James G.; Lin, Shawn-Yu; Hetherington, Dale L.; Smith, Bradley K.

    1999-01-01

    A method is disclosed for fabricating a two- or three-dimensional photonic bandgap structure (also termed a photonic crystal, photonic lattice, or photonic dielectric structure). The method uses microelectronic integrated circuit (IC) processes to fabricate the photonic bandgap structure directly upon a silicon substrate. One or more layers of arrayed elements used to form the structure are deposited and patterned, with chemical-mechanical polishing being used to planarize each layer for uniformity and a precise vertical tolerancing of the layer. The use of chemical-mechanical planarization allows the photonic bandgap structure to be formed over a large area with a layer uniformity of about two-percent. Air-gap photonic bandgap structures can also be formed by removing a spacer material separating the arrayed elements by selective etching. The method is useful for fabricating photonic bandgap structures including Fabry-Perot resonators and optical filters for use at wavelengths in the range of about 0.2-20 .mu.m.

  3. Fiber optic detector for immuno-testing

    DOE Patents [OSTI]

    Partin, Judy K.; Ward, Thomas E.; Grey, Alan E.

    1992-01-01

    A portable fiber optic detector that senses the presence of specific target chemicals in air or a gas by exchanging the target chemical for a fluoroescently-tagged antigen that is bound to an antibody which is in turn attached to an optical fiber. Replacing the fluorescently-tagged antigen reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

  4. Optical properties of La{sub 2}CuO{sub 4} and La{sub 2-x}Ca{sub x}CuO{sub 4} crystallites in UV-vis-NIR region synthesized by sol-gel process

    SciTech Connect (OSTI)

    Li Yifeng; Huang Jianfeng Cao Liyun; Wu Jianpeng; Fei Jie

    2012-02-15

    La{sub 2}CuO{sub 4} and La{sub 2-x}Ca{sub x}CuO{sub 4} crystallites were prepared via a simple sol-gel process. The as-prepared La{sub 2}CuO{sub 4} and La{sub 2} {sub -x}Ca{sub x}CuO{sub 4} crystallites were characterized by X-ray diffraction, transmission electron microscope and UV-vis-NIR spectra. Results show that the grain size of La{sub 2}CuO{sub 4} crystallites increases with the increase of heat treatment temperature from 600 Degree-Sign C to 800 Degree-Sign C. Optical properties show that La{sub 2}CuO{sub 4} crystallites have broad absorption both in the UV-vis region and in the NIR region. The band gap of the as-prepared crystallites decreases from 1.367 eV to 1.284 eV with the increase of calcination temperature from 600 Degree-Sign C to 800 Degree-Sign C. In the series of La{sub 2-x}Ca{sub x}CuO{sub 4} compounds (x = 0.05, 0.08, 0.10, 0.12, 0.15 and 0.20), all of the samples exhibit an orthogonal crystal structure and the solubility limit of Ca{sup 2+} in La{sub 2}CuO{sub 4} is within the range of x = 0.12-0.15. In the whole UV-vis-NIR region, La{sub 2-x}Ca{sub x}CuO{sub 4} crystallites exhibit a broad absorption and the corresponding band gap first increases and then decreases with increasing of Ca{sup 2+} content. - Highlights: Black-Right-Pointing-Pointer The optical band gap can be tuned by adjusting the grain size and Ca{sup 2+} content. Black-Right-Pointing-Pointer La{sub 2}CuO{sub 4} crystallites exhibit a broad absorption band both in the UV-vis region and in the NIR region. Black-Right-Pointing-Pointer The band gap increases from 1.284 eV to 1.319 eV with the decrease of heat treatment temperature. Black-Right-Pointing-Pointer In the whole UV-vis-NIR region, the La{sub 2-x}Ca{sub x}CuO{sub 4} crystallites displayed a broad absorption. Black-Right-Pointing-Pointer The band gap of La{sub 2-x}Ca{sub x}CuO{sub 4} increases linearly with doping level when 0 {<=} x {<=} 0.12.

  5. Photonic Doppler velocimetry lens array probe incorporating stereo imaging

    SciTech Connect (OSTI)

    Malone, Robert M.; Kaufman, Morris I.

    2015-09-01

    A probe including a multiple lens array is disclosed to measure velocity distribution of a moving surface along many lines of sight. Laser light, directed to the moving surface is reflected back from the surface and is Doppler shifted, collected into the array, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to the multiple lens array. Numerous fibers in a fiber array project numerous rays to establish many measurement points at numerous different locations. One or more lens groups may be replaced with imaging lenses so a stereo image of the moving surface can be recorded. Imaging a portion of the surface during initial travel can determine whether the surface is breaking up.

  6. Bloch theory of entangled photon generation in nonlinear photonic crystals

    SciTech Connect (OSTI)

    Irvine, William T.M.; Dood, Michiel J.A. de; Bouwmeester, Dirk [Department of Physics, University of California, Santa Barbara, California 93106 (United States)

    2005-10-15

    We present a quantum-mechanical description of parametric down conversion and phase matching of Bloch waves in nonlinear photonic crystals. We discuss the theory in one-dimensional Bragg structures giving a recipe for calculating the down-converted emission strength and direction. We exemplify the discussion by making explicit analytical predictions for the emission amplitude and direction from a one-dimensional structure that consists of alternating layers of Al{sub 0.4}Ga{sub 0.6}As and air. We show that the emission is suitable for the extraction of polarization-entangled photons.

  7. Integrated optical tamper sensor with planar waveguide

    DOE Patents [OSTI]

    Carson, R.F.; Casalnuovo, S.A.

    1993-01-05

    A monolithic optical tamper sensor, comprising an optical emitter and detector, connected by an optical waveguide and placed into the critical entry plane of an enclosed sensitive region, the tamper sensor having a myriad of scraps of a material optically absorbent at the wavelength of interest, such that when the absorbent material is in place on the waveguide, an unique optical signature can be recorded, but when entry is attempted into the enclosed sensitive region, the scraps of absorbent material will be displaced and the optical/electrical signature of the tamper sensor will change and that change can be recorded.

  8. Integrated optical tamper sensor with planar waveguide

    DOE Patents [OSTI]

    Carson, Richard F.; Casalnuovo, Stephen A.

    1993-01-01

    A monolithic optical tamper sensor, comprising an optical emitter and detector, connected by an optical waveguide and placed into the critical entry plane of an enclosed sensitive region, the tamper sensor having a myriad of scraps of a material optically absorbent at the wavelength of interest, such that when the absorbent material is in place on the waveguide, an unique optical signature can be recorded, but when entry is attempted into the enclosed sensitive region, the scraps of absorbent material will be displaced and the optical/electrical signature of the tamper sensor will change and that change can be recorded.

  9. Passive thermo-optic feedback for robust athermal photonic systems...

    Office of Scientific and Technical Information (OSTI)

    NM (United States) Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

  10. CRC handbook of laser science and technology. Volume 3. Optical materials, Part 1 - Nonlinear optical properties/radiation damage

    SciTech Connect (OSTI)

    Weber, M.J.

    1986-01-01

    This book examines the nonlinear optical properties of laser materials. The physical radiation effects on laser materials are also considered. Topics considered include: nonlinear optical properties; nonlinear and harmonic generation materials; two-photon absorption; nonlinear refractive index; stimulated Raman scattering; radiation damage; crystals; and glasses.

  11. Quantum photonics hybrid integration platform

    SciTech Connect (OSTI)

    Murray, E.; Floether, F. F.; Ellis, D. J. P.; Meany, T.; Bennett, A. J. Shields, A. J.; Lee, J. P.; Griffiths, J. P.; Jones, G. A. C.; Farrer, I.; Ritchie, D. A.

    2015-10-26

    Fundamental to integrated photonic quantum computing is an on-chip method for routing and modulating quantum light emission. We demonstrate a hybrid integration platform consisting of arbitrarily designed waveguide circuits and single-photon sources. InAs quantum dots (QD) embedded in GaAs are bonded to a SiON waveguide chip such that the QD emission is coupled to the waveguide mode. The waveguides are SiON core embedded in a SiO{sub 2} cladding. A tuneable Mach Zehnder interferometer (MZI) modulates the emission between two output ports and can act as a path-encoded qubit preparation device. The single-photon nature of the emission was verified using the on-chip MZI as a beamsplitter in a Hanbury Brown and Twiss measurement.

  12. Optical probe

    DOE Patents [OSTI]

    Hencken, Kenneth; Flower, William L.

    1999-01-01

    A compact optical probe is disclosed particularly useful for analysis of emissions in industrial environments. The instant invention provides a geometry for optically-based measurements that allows all optical components (source, detector, rely optics, etc.) to be located in proximity to one another. The geometry of the probe disclosed herein provides a means for making optical measurements in environments where it is difficult and/or expensive to gain access to the vicinity of a flow stream to be measured. Significantly, the lens geometry of the optical probe allows the analysis location within a flow stream being monitored to be moved while maintaining optical alignment of all components even when the optical probe is focused on a plurality of different analysis points within the flow stream.

  13. Atlas of solar hidden photon emission

    SciTech Connect (OSTI)

    Redondo, Javier

    2015-07-20

    Hidden photons, gauge bosons of a U(1) symmetry of a hidden sector, can constitute the dark matter of the universe and a smoking gun for large volume compactifications of string theory. In the sub-eV mass range, a possible discovery experiment consists on searching the copious flux of these particles emitted from the Sun in a helioscope setup à la Sikivie. In this paper, we compute in great detail the flux of HPs from the Sun, a necessary ingredient for interpreting such experiments. We provide a detailed exposition of transverse photon-HP oscillations in inhomogenous media, with special focus on resonance oscillations, which play a leading role in many cases. The region of the Sun emitting HPs resonantly is a thin spherical shell for which we justify an averaged-emission formula and which implies a distinctive morphology of the angular distribution of HPs on Earth in many cases. Low mass HPs with energies in the visible and IR have resonances very close to the photosphere where the solar plasma is not fully ionised and requires building a detailed model of solar refraction and absorption. We present results for a broad range of HP masses (from 0–1 keV) and energies (from the IR to the X-ray range), the most complete atlas of solar HP emission to date.

  14. Apparatus for photon activation positron annihilation analysis

    DOE Patents [OSTI]

    Akers, Douglas W.

    2007-06-12

    Non-destructive testing apparatus according to one embodiment of the invention comprises a photon source. The photon source produces photons having predetermined energies and directs the photons toward a specimen being tested. The photons from the photon source result in the creation of positrons within the specimen being tested. A detector positioned adjacent the specimen being tested detects gamma rays produced by annihilation of positrons with electrons. A data processing system operatively associated with the detector produces output data indicative of a lattice characteristic of the specimen being tested.

  15. Thermal emission and absorption of radiation in finite inverted-opal photonic crystals

    SciTech Connect (OSTI)

    Florescu, Marian; Stimpson, Andrew J.; Lee, Hwang; Dowling, Jonathan

    2005-09-15

    We study theoretically the optical properties of a finite inverted-opal photonic crystal. The light-matter interaction is strongly affected by the presence of the three-dimensional photonic crystal and the alterations of the light emission and absorption processes can be used to suppress or enhance the thermal emissivity and absorptivity of the dielectric structure. We investigate the influence of the absorption present in the system on the relevant band edge frequencies that control the optical response of the photonic crystal. Our study reveals that the absorption processes cause spectral broadening and shifting of the band edge optical resonances, and determine a strong reduction of the photonic band gap spectral range. Using the angular and spectral dependence of the band edge frequencies for stop bands along different directions, we argue that by matching the blackbody emission spectrum peak with a prescribed maximum of the absorption coefficient, it is possible to achieve an angle-sensitive enhancement of the thermal emission/absorption of radiation. This result opens a way to realize a frequency-sensitive and angle-sensitive photonic crystal absorbers/emitters.

  16. Optical keyboard

    DOE Patents [OSTI]

    Veligdan, James T.; Feichtner, John D.; Phillips, Thomas E.

    2001-01-01

    An optical keyboard includes an optical panel having optical waveguides stacked together. First ends of the waveguides define an inlet face, and opposite ends thereof define a screen. A projector transmits a light beam outbound through the waveguides for display on the screen as a keyboard image. A light sensor is optically aligned with the inlet face for sensing an inbound light beam channeled through the waveguides from the screen upon covering one key of the keyboard image.

  17. Tests of innovative photon detectors and integrated electronics for the large-area CLAS12 ring-imaging Cherenkov detector

    SciTech Connect (OSTI)

    Contalbrigo, Marco

    2015-07-01

    A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab. Its aim is to study the 3D nucleon structure in the yet poorly explored valence region by deep-inelastic scattering, and to perform precision measurements in hadron spectroscopy. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and a densely packed and highly segmented photon detector. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). Extensive tests have been performed on Hamamatsu H8500 and novel flat multi-anode photomultipliers under development and on various types of silicon photomultipliers. A large scale prototype based on 28 H8500 MA-PMTs has been realized and tested with few GeV/c hadron beams at the T9 test-beam facility of CERN. In addition a small prototype was used to study the response of customized SiPM matrices within a temperature interval ranging from 25 down to –25 °C. The preliminary results of the individual photon detector tests and of the prototype performance at the test-beams are here reported.

  18. Optical ionization detector (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    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. ...

  19. Method and apparatus for optical phase error correction

    DOE Patents [OSTI]

    DeRose, Christopher; Bender, Daniel A.

    2014-09-02

    The phase value of a phase-sensitive optical device, which includes an optical transport region, is modified by laser processing. At least a portion of the optical transport region is exposed to a laser beam such that the phase value is changed from a first phase value to a second phase value, where the second phase value is different from the first phase value. The portion of the optical transport region that is exposed to the laser beam can be a surface of the optical transport region or a portion of the volume of the optical transport region. In an embodiment of the invention, the phase value of the optical device is corrected by laser processing. At least a portion of the optical transport region is exposed to a laser beam until the phase value of the optical device is within a specified tolerance of a target phase value.

  20. Optical Switch

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

    seven wonders / optical switch 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 rotates the polarization of a laser beam when a voltage is applied across an electro-optic crystal. Depending on the voltage applied, the Pockels cell either allows light to pass through or to reflect off a polarizer, creating an optical switch. For each of NIF's 192 beamlines, a PEPC allows the laser

  1. Photonic band gap of a graphene-embedded quarter-wave stack

    SciTech Connect (OSTI)

    Fan, Yuancheng; Wei, Zeyong; Li, Hongqiang; Chen, Hong; Soukoulis, Costas M

    2013-12-10

    Here, we present a mechanism for tailoring the photonic band structure of a quarter-wave stack without changing its physical periods by embedding conductive sheets. Graphene is utilized and studied as a realistic, two-dimensional conductive sheet. In a graphene-embedded quarter-wave stack, the synergic actions of Bragg scattering and graphene conductance contributions open photonic gaps at the center of the reduced Brillouin zone that are nonexistent in conventional quarter-wave stacks. Such photonic gaps show giant, loss-independent density of optical states at the fixed lower-gap edges, of even-multiple characteristic frequency of the quarter-wave stack. The conductive sheet-induced photonic gaps provide a platform for the enhancement of light-matter interactions.

  2. Coherent optical monolithic phased-array antenna steering system

    DOE Patents [OSTI]

    Hietala, Vincent M.; Kravitz, Stanley H.; Vawter, Gregory A.

    1994-01-01

    An optical-based RF beam steering system for phased-array antennas comprising a photonic integrated circuit (PIC). The system is based on optical heterodyning employed to produce microwave phase shifting by a monolithic PIC constructed entirely of passive components. Microwave power and control signal distribution to the antenna is accomplished by optical fiber, permitting physical separation of the PIC and its control functions from the antenna. The system reduces size, weight, complexity, and cost of phased-array antenna systems.

  3. Photonic crystal surface-emitting lasers

    DOE Patents [OSTI]

    Chua, Song Liang; Lu, Ling; Soljacic, Marin

    2015-06-23

    A photonic-crystal surface-emitting laser (PCSEL) includes a gain medium electromagnetically coupled to a photonic crystal whose energy band structure exhibits a Dirac cone of linear dispersion at the center of the photonic crystal's Brillouin zone. This Dirac cone's vertex is called a Dirac point; because it is at the Brillouin zone center, it is called an accidental Dirac point. Tuning the photonic crystal's band structure (e.g., by changing the photonic crystal's dimensions or refractive index) to exhibit an accidental Dirac point increases the photonic crystal's mode spacing by orders of magnitudes and reduces or eliminates the photonic crystal's distributed in-plane feedback. Thus, the photonic crystal can act as a resonator that supports single-mode output from the PCSEL over a larger area than is possible with conventional PCSELs, which have quadratic band edge dispersion. Because output power generally scales with output area, this increase in output area results in higher possible output powers.

  4. National Ignition Facility & Photon Science

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

    Results from this relatively new field of research, known as high-energy- density (hed) ... optical physics, radiation sources, radiative properties, and other areas of science. ...

  5. CNEEC - TRG2: Nanoscale Control over Photons and Electrons

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

    TRG2: Nanoscale Control over Photons and Electrons TRG2 Leader: Mark Brongersma This group’s aim is to boost the efficiency of photovoltaic (PV) and photoelectrochemical (PEC) devices by engineering new materials at the nanoscale that offer excellent light absorption and subsequent charge extraction. The driving mechanism in conventional PV and photocatalytic devices is to convert sunlight into electrons and holes and to collect them in spatially distinct regions. Unfortunately, many of the

  6. Effect of window reflections on photonic Doppler velocimetry measurements

    SciTech Connect (OSTI)

    Ao, T.; Dolan, D. H.

    2011-02-15

    Photonic Doppler velocimetry (PDV) has rapidly become a standard diagnostic for measuring velocities in dynamic compression research. While free surface velocity measurements are fairly straightforward, complications occur when PDV is used to measure a dynamically loaded sample through a window. Fresnel reflections can severely affect the velocity and time resolution of PDV measurements, especially for low-velocity transients. Shock experiments of quartz compressed between two sapphire plates demonstrate how optical window reflections cause ringing in the extracted PDV velocity profile. Velocity ringing is significantly reduced by using either a wedge window or an antireflective coating.

  7. Microphotonic parabolic light directors fabricated by two-photon lithography

    SciTech Connect (OSTI)

    Atwater, Jackson H; Spinelli, P.; Kosten, Emily D; Parsons, J.; Van Lare, C; Van de Groep, J; Garcia de Abajo, J.; Polman, Albert; Atwater, Harry A.

    2011-01-01

    We have fabricated microphotonic parabolic light directors using two-photon lithography, thin-film processing, and aperture formation by focused ion beam lithography. Optical transmission measurements through upright parabolic directors 22 ?m high and 10 ?m in diameter exhibit strong beam directivity with a beam divergence of 5.6, in reasonable agreement with ray-tracing and full-field electromagnetic simulations. The results indicate the suitability of microphotonic parabolic light directors for producing collimated beams for applications in advanced solar cell and light-emitting diode designs.

  8. Measuring single-shot, picosecond optical damage threshold in Ge, Si, and sapphire with a 5.1-μm laser

    SciTech Connect (OSTI)

    Agustsson, R.; Pogorelsky, I.; Arab, E.; Murokh, A.; O"Shea, B.; Ovodenko, A.; Rosenzweig, J.; Solovyov, V.; Tilton, R.

    2015-11-18

    Optical photonic structures driven by picosecond, GW-class lasers are emerging as promising novel sources of electron beams and high quality X-rays. Due to quadratic dependence on wavelength of the laser ponderomotive potential, the performance of such sources scales very favorably towards longer drive laser wavelengths. However, to take full advantage of photonic structures at mid-IR spectral region, it is important to determine optical breakdown limits of common optical materials. To this end, an experimental study was carried out at a wavelength of 5 µm, using a frequency-doubled CO2 laser source, with 5 ps pulse length. Single-shot optical breakdowns were detected and characterized at different laser intensities, and damage threshold values of 0.2, 0.3, and 7.0 J/cm2, were established for Ge, Si, and sapphire, respectively. As a result, the measured damage threshold values were stable and repeatable within individual data sets, and across varying experimental conditions.

  9. Measuring single-shot, picosecond optical damage threshold in Ge, Si, and sapphire with a 5.1-μm laser

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

    Agustsson, R.; Pogorelsky, I.; Arab, E.; Murokh, A.; O"Shea, B.; Ovodenko, A.; Rosenzweig, J.; Solovyov, V.; Tilton, R.

    2015-11-18

    Optical photonic structures driven by picosecond, GW-class lasers are emerging as promising novel sources of electron beams and high quality X-rays. Due to quadratic dependence on wavelength of the laser ponderomotive potential, the performance of such sources scales very favorably towards longer drive laser wavelengths. However, to take full advantage of photonic structures at mid-IR spectral region, it is important to determine optical breakdown limits of common optical materials. To this end, an experimental study was carried out at a wavelength of 5 µm, using a frequency-doubled CO2 laser source, with 5 ps pulse length. Single-shot optical breakdowns were detectedmore » and characterized at different laser intensities, and damage threshold values of 0.2, 0.3, and 7.0 J/cm2, were established for Ge, Si, and sapphire, respectively. As a result, the measured damage threshold values were stable and repeatable within individual data sets, and across varying experimental conditions.« less

  10. Frequency splitter based on the directional emission from surface modes in dielectric photonic crystal structures

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

    Tasolamprou, Anna C.; Zhang, Lei; Kafesaki, Maria; Koschny, Thomas; Soukoulis, Costas M.

    2015-05-19

    We demonstrate the numerical design and the experimental validation of frequency dependent directional emission from a dielectric photonic crystal structure. The wave propagates through a photonic crystal line-defect waveguide, while a surface layer at the termination of the photonic crystal enables the excitation of surface modes and a subsequent grating layer transforms the surface energy into outgoing propagating waves of the form of a directional beam. The angle of the beam is controlled by the frequency and the structure operates as a frequency splitter in the intermediate and far field region.

  11. High-Energy QCD Asymptotics of Photon--Photon Collisions

    SciTech Connect (OSTI)

    Brodsky, Stanley J.

    2002-07-26

    The high-energy behavior of the total cross section for highly virtual photons, as predicted by the BFKL equation at next-to-leading order (NLO) in QCD, is discussed. The NLO BFKL predictions, improved by the BLM optimal scale setting, are in good agreement with recent OPAL and L3 data at CERN LEP2. NLO BFKL predictions for future linear colliders are presented.

  12. Opal photonic crystals infiltrated with chalcogenide glasses

    SciTech Connect (OSTI)

    Astratov, V. N.; Adawi, A. M.; Skolnick, M. S.; Tikhomirov, V. K.; Lyubin, V.; Lidzey, D. G.; Ariu, M.; Reynolds, A. L.

    2001-06-25

    Composite opal structures for nonlinear applications are obtained by infiltration with chalcogenide glasses As{sub 2}S{sub 3} and AsSe by precipitation from solution. Analysis of spatially resolved optical spectra reveals that the glass aggregates into submillimeter areas inside the opal. These areas exhibit large shifts in the optical stop bands by up to 80 nm, and by comparison with modelling are shown to have uniform glass filling factors of opal pores up to 40%. Characterization of the domain structure of the opals prior to infiltration by large area angle-resolved spectroscopy is an important step in the analysis of the properties of the infiltrated regions. {copyright} 2001 American Institute of Physics.

  13. Fluxes and spectra of quasimonochromatic annihilation photons for studying E1 giant resonances in nuclei

    SciTech Connect (OSTI)

    Dzhilavyan, L. Z.

    2014-12-15

    The fluxes and spectra of quasimonochromatic photons originating from the in-flight annihilation of positrons interacting with electrons of targets are analyzed in the energy region characteristic of the excitation of E1 giant resonances in nuclei. Targets of small thickness and low atomic number are used. The dependences of the spectra on the energy and angle (and their scatter) for positrons incident to the target, on the collimation angle for photons, and on the target thickness are studied.

  14. New Optical Sensor Suite for Ultrahigh Temperature Fossil Fuel Application

    SciTech Connect (OSTI)

    John Coggin; Tom Flynn; Jonas Ivasauskas; Daniel Kominsky; Carrie Kozikowski; Russell May; Michael Miller; Tony Peng; Gary Pickrell; Raymond Rumpf; Kelly Stinson-Bagby; Dan Thorsen; Rena Wilson

    2007-12-31

    Accomplishments of a program to develop and demonstrate photonic sensor technology for the instrumentation of advanced powerplants and solid oxide fuel cells are described. The goal of this project is the research and development of advanced, robust photonic sensors based on improved sapphire optical waveguides, and the identification and demonstration of applications of the new sensors in advanced fossil fuel power plants, where the new technology will contribute to improvements in process control and monitoring.

  15. X-ray photonic microsystems for the manipulation of synchrotron light

    SciTech Connect (OSTI)

    Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; Schwartz, C. P.; Wang, Jin; López, D.; Shenoy, G. K.

    2015-05-05

    In this study, photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractive optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.

  16. Superior optical nonlinearity of an exceptional fluorescent stilbene dye

    SciTech Connect (OSTI)

    He, Tingchao; Sreejith, Sivaramapanicker; Zhao, Yanli; Gao, Yang; Grimsdale, Andrew C.; Lin, Xiaodong E-mail: hdsun@ntu.edu.sg; Sun, Handong E-mail: hdsun@ntu.edu.sg

    2015-03-16

    Strong multiphoton absorption and harmonic generation in organic fluorescent chromophores are, respectively, significant in many fields of research. However, most of fluorescent chromophores fall short of the full potential due to the absence of the combination of such different nonlinear upconversion behaviors. Here, we demonstrate that an exceptional fluorescent stilbene dye could exhibit efficient two- and three-photon absorption under the excitation of femtosecond pulses in solution phase. Benefiting from its biocompatibility and strong excited state absorption behavior, in vitro two-photon bioimaging and superior optical limiting have been exploited, respectively. Simultaneously, the chromophore could generate efficient three-photon excited fluorescence and third-harmonic generation (THG) when dispersed into PMMA film, circumventing the limitations of classical fluorescent chromophores. Such chromophore may find application in the production of coherent light sources of higher photon energy. Moreover, the combination of three-photon excited fluorescence and THG can be used in tandem to provide complementary information in biomedical studies.

  17. Photonic band gap structure simulator

    DOE Patents [OSTI]

    Chen, Chiping; Shapiro, Michael A.; Smirnova, Evgenya I.; Temkin, Richard J.; Sirigiri, Jagadishwar R.

    2006-10-03

    A system and method for designing photonic band gap structures. The system and method provide a user with the capability to produce a model of a two-dimensional array of conductors corresponding to a unit cell. The model involves a linear equation. Boundary conditions representative of conditions at the boundary of the unit cell are applied to a solution of the Helmholtz equation defined for the unit cell. The linear equation can be approximated by a Hermitian matrix. An eigenvalue of the Helmholtz equation is calculated. One computation approach involves calculating finite differences. The model can include a symmetry element, such as a center of inversion, a rotation axis, and a mirror plane. A graphical user interface is provided for the user's convenience. A display is provided to display to a user the calculated eigenvalue, corresponding to a photonic energy level in the Brilloin zone of the unit cell.

  18. NIF & Photon Science News

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

    nifps_news NIF & Photon Science News × Subscribe to our News Alerts * Your Email Address: * Preferred Format: HTML Text Subscribe August 24, 2016 Tweet Spotlight on: Discovery Science A Big Week for NIF Discovery Science During the week of July 31 to Aug. 4, five groups of NIF users worked with LLNL researchers to carry out a successful NIF Discovery Science shot week. The teams conducted 13 experiments in five separate basic high energy density (HED) science experimental campaigns in five

  19. Selenium semiconductor core optical fibers

    SciTech Connect (OSTI)

    Tang, G. W.; Qian, Q. Peng, K. L.; Wen, X.; Zhou, G. X.; Sun, M.; Chen, X. D.; Yang, Z. M.

    2015-02-15

    Phosphate glass-clad optical fibers containing selenium (Se) semiconductor core were fabricated using a molten core method. The cores were found to be amorphous as evidenced by X-ray diffraction and corroborated by Micro-Raman spectrum. Elemental analysis across the core/clad interface suggests that there is some diffusion of about 3 wt % oxygen in the core region. Phosphate glass-clad crystalline selenium core optical fibers were obtained by a postdrawing annealing process. A two-cm-long crystalline selenium semiconductor core optical fibers, electrically contacted to external circuitry through the fiber end facets, exhibit a three times change in conductivity between dark and illuminated states. Such crystalline selenium semiconductor core optical fibers have promising utility in optical switch and photoconductivity of optical fiber array.

  20. Regional Purchasing

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

    Regional Partnerships Regional Partnerships DOE's Regional Carbon Sequestration Partnerships Program DOE has created a network of seven Regional Carbon Sequestration Partnerships (RCSPs) to help develop the technology, infrastructure, and regulations to implement large-scale CO2 storage (also called carbon sequestration) in different regions and geologic formations within the Nation. Collectively, the seven RCSPs represent regions encompassing: 97 percent of coal-fired CO2 emissions; 97 percent

  1. Single photon imaging and timing array sensor apparatus and method

    DOE Patents [OSTI]

    Smith, R. Clayton

    2003-06-24

    An apparatus and method are disclosed for generating a three-dimension image of an object or target. The apparatus is comprised of a photon source for emitting a photon at a target. The emitted photons are received by a photon receiver for receiving the photon when reflected from the target. The photon receiver determines a reflection time of the photon and further determines an arrival position of the photon on the photon receiver. An analyzer is communicatively coupled to the photon receiver, wherein the analyzer generates a three-dimensional image of the object based upon the reflection time and the arrival position.

  2. Photonic band gaps in three-dimensional network structures with short-range order

    SciTech Connect (OSTI)

    Liew, Seng Fatt; Noh, Heeso; Yang, Jin-Kyu; Schreck, Carl F.; Dufresne, Eric R.; O'Hern, Corey S.; Cao, Hui

    2011-12-15

    We present a systematic study of photonic band gaps (PBGs) in three-dimensional (3D) photonic amorphous structures (PASs) with short-range order. From calculations of the density of optical states (DOS) for PASs with different topologies, we find that tetrahedrally connected dielectric networks produce the largest isotropic PBGs. Local uniformity and tetrahedral order are essential to the formation of PBGs in PASs, in addition to short-range geometric order. This work demonstrates that it is possible to create broad, isotropic PBGs for vector light fields in 3D PASs without long-range order.

  3. Conditional generation of arbitrary single-mode quantum states of light by repeated photon subtractions

    SciTech Connect (OSTI)

    Fiurasek, Jaromir; Garcia-Patron, Raul; Cerf, Nicolas J.

    2005-09-15

    We propose a scheme for the conditional generation of arbitrary finite superpositions of Fock states in a single mode of a traveling optical field. The setup requires a source of squeezed vacuum states, beam splitters, strong coherent beams, photodetectors with single-photon sensitivity, and a final squeezer. If we want to generate a squeezed superposition of Fock states, which is sufficient in several applications, then the last squeezer is not even needed. The thrust of this method is that it achieves a high fidelity without requiring photodetectors with a high efficiency or a single-photon resolution. The possibility to improve its scaling by using a quantum memory is also discussed.

  4. Enhancement of photoluminescence and raman scattering in one-dimensional photonic crystals based on porous silicon

    SciTech Connect (OSTI)

    Gonchar, K. A.; Musabek, G. K.; Taurbayev, T. I.; Timoshenko, V. Yu.

    2011-05-15

    In porous-silicon-based multilayered structures that exhibit the properties of one-dimensional photonic crystals, an increase in the photoluminescence and Raman scattering intensities is observed upon optical excitation at the wavelength 1.064 {mu}m. When the excitation wavelength falls within the edge of the photonic band gap of the structures, a multiple increase (by a factor larger than 400) in the efficiency of Raman scattering is detected. The effect is attributed to partial localization of excitation light and, correspondingly, to the much longer time of interaction of light with the material in the structures.

  5. Non-degenerate two-photon absorption in silicon waveguides: Analytical and experimental study

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

    Zhang, Yanbing; Husko, Chad; Lefrancois, Simon; Rey, Isabella H.; Krauss, Thomas F.; Schrder, Jochen; Eggleton, Benjamin J.

    2015-06-22

    We theoretically and experimentally investigate the nonlinear evolution of two optical pulses in a silicon waveguide. We provide an analytic solution for the weak probe wave undergoing non-degenerate two-photon absorption (TPA) from the strong pump. At larger pump intensities, we employ a numerical solution to study the interplay between TPA and photo-generated free carriers. We develop a simple and powerful approach to extract and separate out the distinct loss contributions of TPA and free-carrier absorption from readily available experimental data. Our analysis accounts accurately for experimental results in silicon photonic crystal waveguides.

  6. Non-degenerate two-photon absorption in silicon waveguides. Analytical and experimental study

    SciTech Connect (OSTI)

    Zhang, Yanbing; Husko, Chad; Lefrancois, Simon; Rey, Isabella H.; Krauss, Thomas F.; Schröder, Jochen; Eggleton, Benjamin J.

    2015-06-22

    We theoretically and experimentally investigate the nonlinear evolution of two optical pulses in a silicon waveguide. We provide an analytic solution for the weak probe wave undergoing non-degenerate two-photon absorption (TPA) from the strong pump. At larger pump intensities, we employ a numerical solution to study the interplay between TPA and photo-generated free carriers. We develop a simple and powerful approach to extract and separate out the distinct loss contributions of TPA and free-carrier absorption from readily available experimental data. Our analysis accounts accurately for experimental results in silicon photonic crystal waveguides.

  7. Coupled double-layer Fano resonance photonic crystal filters with lattice-displacement

    SciTech Connect (OSTI)

    Shuai, Yichen; Zhao, Deyin; Singh Chadha, Arvinder; Zhou, Weidong; Seo, Jung-Hun; Ma, Zhenqiang; Yang, Hongjun; Semerane, Inc., Arlington, Texas 76010 ; Fan, Shanhui

    2013-12-09

    We present here ultra-compact high-Q Fano resonance filters with displaced lattices between two coupled photonic crystal slabs, fabricated with crystalline silicon nanomembrane transfer printing and aligned e-beam lithography techniques. Theoretically, with the control of lattice displacement between two coupled photonic crystal slabs layers, optical filter Q factors can approach 211 000 000 for the design considered here. Experimentally, Q factors up to 80 000 have been demonstrated for a filter design with target Q factor of 130 000.

  8. Fiber optic coupled optical sensor

    DOE Patents [OSTI]

    Fleming, Kevin J. (Albuquerque, NM)

    2001-01-01

    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.

  9. Local Optical Spectroscopies for Subnanometer Spatial Resolution Chemical Imaging

    SciTech Connect (OSTI)

    Weiss, Paul

    2014-01-20

    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.

  10. A Fisheye Lens as a Photonic Doppler Velocimetry Probe

    SciTech Connect (OSTI)

    Frogget, B C; Cox, B C; DeVore, D O; Esquibel, D L; Frayer, D K; Furlanetto, M R; Holtkamp, D B; Kaufman, M I; Malone, R M

    2012-09-01

    A new fisheye lens design is used as a miniature probe to measure the velocity distribution of an imploding surface along many lines of sight. Laser light, directed and scattered back along each beam on the surface, is Doppler shifted by the moving surface and collected into the launching fiber. The received light is mixed with reference laser light in each optical fiber in a technique called photonic Doppler velocimetry, providing a continuous time record. An array of single-mode optical fibers sends laser light through the fisheye lens. The lens consists of an index-matching positive element, two positive doublet groups, and two negative singlet elements. The optical design minimizes beam diameters, physical size, and back reflections for excellent signal collection. The fiber array projected through the fisheye lens provides many measurement points of surface coverage over a hemisphere with very little crosstalk. The probe measures surface movement with only a small encroachment into the center of the cavity. The fiber array is coupled to the index-matching element using index-matching gel. The array is bonded and sealed into a blast tube for ease of assembly and focusing. This configuration also allows the fiber array to be flat polished at a common object plane. In areas where increased measurement point density is desired, the fibers can be close packed. To further increase surface density coverage, smaller-diameter cladding optical fibers may be used.

  11. Heating up the Galaxy with hidden photons

    SciTech Connect (OSTI)

    Dubovsky, Sergei; Hernández-Chifflet, Guzmán

    2015-12-29

    We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point out that as a result of the Galactic plasma shielding direct detection of ultra-light photons in this mass range is especially challenging. However, we demonstrate that ultra-light hidden photon dark matter provides a powerful heating source for the ionized interstellar medium. This results in a strong bound on the kinetic mixing between hidden and regular photons all the way down to the hidden photon masses of order 10{sup −20} eV.

  12. Center of mass energy and system-size dependence of photon production at forward rapidity at RHIC

    SciTech Connect (OSTI)

    STAR Collaboration; Abelev, Betty

    2010-07-05

    We present the multiplicity and pseudorapidity distributions of photons produced in Au+Au and Cu+Cu collisions at {radical}s{sub NN} = 62.4 and 200 GeV. The photons are measured in the region -3.7 < {eta} < -2.3 using the photon multiplicity detector in the STAR experiment at RHIC. The number of photons produced per average number of participating nucleon pairs increases with the beam energy and is independent of the collision centrality. For collisions with similar average numbers of participating nucleons the photon multiplicities are observed to be similar for Au+Au and Cu+Cu collisions at a given beam energy. The ratios of the number of charged particles to photons in the measured pseudorapidity range are found to be 1.4 {+-} 0.1 and 1.2 {+-} 0.1 for {radical}s{sub NN} = 62.4 GeV and 200 GeV, respectively. The energy dependence of this ratio could reflect varying contributions from baryons to charged particles, while mesons are the dominant contributors to photon production in the given kinematic region. The photon pseudorapidity distributions normalized by average number of participating nucleon pairs, when plotted as a function of {eta} - ybeam, are found to follow a longitudinal scaling independent of centrality and colliding ion species at both beam energies.

  13. Semiconductor-based photoelectrochemical water splitting at the limit of very wide depletion region

    SciTech Connect (OSTI)

    Liu, Mingzhao; Lyons, John L.; Yan, Danhua H.; Hybertsen, Mark S.

    2015-11-23

    In semiconductor-based photoelectrochemical (PEC) water splitting, carrier separation and delivery largely relies on the depletion region formed at the semiconductor/water interface. As a Schottky junction device, the trade-off between photon collection and minority carrier delivery remains a persistent obstacle for maximizing the performance of a water splitting photoelectrode. Here, it is demonstrated that the PEC water splitting efficiency for an n-SrTiO3 (n-STO) photoanode is improved very significantly despite its weak indirect band gap optical absorption (α < 10⁴ cm⁻¹), by widening the depletion region through engineering its doping density and profile. Graded doped n-SrTiO3 photoanodes are fabricated with their bulk heavily doped with oxygen vacancies but their surface lightly doped over a tunable depth of a few hundred nanometers, through a simple low temperature re-oxidation technique. The graded doping profile widens the depletion region to over 500 nm, thus leading to very efficient charge carrier separation and high quantum efficiency (>70%) for the weak indirect transition. As a result, this simultaneous optimization of the light absorption, minority carrier (hole) delivery, and majority carrier (electron) transport by means of a graded doping architecture may be useful for other indirect band gap photocatalysts that suffer from a similar problem of weak optical absorption.

  14. Semiconductor-based photoelectrochemical water splitting at the limit of very wide depletion region

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

    Liu, Mingzhao; Lyons, John L.; Yan, Danhua H.; Hybertsen, Mark S.

    2015-11-23

    In semiconductor-based photoelectrochemical (PEC) water splitting, carrier separation and delivery largely relies on the depletion region formed at the semiconductor/water interface. As a Schottky junction device, the trade-off between photon collection and minority carrier delivery remains a persistent obstacle for maximizing the performance of a water splitting photoelectrode. Here, it is demonstrated that the PEC water splitting efficiency for an n-SrTiO3 (n-STO) photoanode is improved very significantly despite its weak indirect band gap optical absorption (α < 10⁴ cm⁻¹), by widening the depletion region through engineering its doping density and profile. Graded doped n-SrTiO3 photoanodes are fabricated with their bulkmore » heavily doped with oxygen vacancies but their surface lightly doped over a tunable depth of a few hundred nanometers, through a simple low temperature re-oxidation technique. The graded doping profile widens the depletion region to over 500 nm, thus leading to very efficient charge carrier separation and high quantum efficiency (>70%) for the weak indirect transition. As a result, this simultaneous optimization of the light absorption, minority carrier (hole) delivery, and majority carrier (electron) transport by means of a graded doping architecture may be useful for other indirect band gap photocatalysts that suffer from a similar problem of weak optical absorption.« less

  15. Optical ionization detector

    DOE Patents [OSTI]

    Wuest, Craig R.; Lowry, Mark E.

    1994-01-01

    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.

  16. Optical ionization detector

    DOE Patents [OSTI]

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

    1994-03-29

    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.

  17. Mission and Goals | Advanced Photon Source

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

    Mission and Goals The mission of the Advanced Photon Source (APS) is to deliver world-class science and technology by operating an outstanding synchrotron radiation research...

  18. Photon Power Technologies PPT | Open Energy Information

    Open Energy Info (EERE)

    PPT Jump to: navigation, search Name: Photon Power Technologies (PPT) Place: Ecully, France Product: French PV system installer for residential and commercial systems. Coordinates:...

  19. MEASURING TEMPORAL PHOTON BUNCHING IN BLACKBODY RADIATION

    SciTech Connect (OSTI)

    Tan, P. K.; Poh, H. S.; Kurtsiefer, C.; Yeo, G. H.; Chan, A. H. E-mail: phyck@nus.edu.sg

    2014-07-01

    Light from thermal blackbody radiators such as stars exhibits photon bunching behavior at sufficiently short timescales. However, with available detector bandwidths, this bunching signal is difficult to observe directly. We present an experimental technique to increase the photon bunching signal in blackbody radiation via spectral filtering of the light source. Our measurements reveal strong temporal photon bunching from blackbody radiation, including the Sun. This technique allows for an absolute measurement of the photon bunching signature g {sup (2)}(0), and thereby a direct statement on the statistical nature of a light source. Such filtering techniques may help revive the interest in intensity interferometry as a tool in astronomy.

  20. Optical properties of armchair (7, 7) single walled carbon nanotubes

    SciTech Connect (OSTI)

    Gharbavi, K.; Badehian, H.

    2015-07-15

    Full potential linearized augmented plane waves method with the generalized gradient approximation for the exchange-correlation potential was applied to calculate the optical properties of (7, 7) single walled carbon nanotubes. The both x and z directions of the incident photons were applied to estimate optical gaps, dielectric function, electron energy loss spectroscopies, optical conductivity, optical extinction, optical refractive index and optical absorption coefficient. The results predict that dielectric function, ε (ω), is anisotropic since it has higher peaks along z-direction than x-direction. The static optical refractive constant were calculated about 1.4 (z-direction) and 1.1 (x- direction). Moreover, the electron energy loss spectroscopy showed a sharp π electron plasmon peaks at about 6 eV and 5 eV for z and x-directions respectively. The calculated reflection spectra show that directions perpendicular to the tube axis have further optical reflection. Moreover, z-direction indicates higher peaks at absorption spectra in low range energies. Totally, increasing the diameter of armchair carbon nanotubes cause the optical band gap, static optical refractive constant and optical reflectivity to decrease. On the other hand, increasing the diameter cause the optical absorption and the optical conductivity to increase. Moreover, the sharp peaks being illustrated at optical spectrum are related to the 1D structure of CNTs which confirm the accuracy of the calculations.

  1. Photon-photon interaction in strong-coupling cavity-atom system

    SciTech Connect (OSTI)

    Yang, Jian; Kwiat, Paul G.

    2014-12-04

    We study photon-photon interactions mediated by a cavity-atom system in the strongcoupling regime of cavity quantum electrodynamics (QED). Different temporal shapes of the incident photons have been explored via numerical calculations. Especially, time-reversed photons can be in the cavity simultaneously and potentially acquire strong interaction with each other, advancing quantum information applications, e.g., quantum non-demolition (QND) measurement.

  2. Resource-Efficient Generataion of Linear Cluster States by Linear Optics with postselection

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

    Uskov, Dmitry B; Alsing, Paul; Fanto, Michael; Kaplan, Lev; Kim, R; Szep, Atilla; Smith IV, Amos M

    2015-01-01

    We report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detectionmore » of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2^n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4^m-1.« less

  3. Resource-Efficient Generataion of Linear Cluster States by Linear Optics with postselection

    SciTech Connect (OSTI)

    Uskov, Dmitry B; Alsing, Paul; Fanto, Michael; Kaplan, Lev; Kim, R; Szep, Atilla; Smith IV, Amos M

    2015-01-01

    We report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2^n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4^m-1.

  4. Resource-efficient generation of linear cluster states by linear optics with postselection

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

    Uskov, D. B.; Alsing, P. M.; Fanto, M. L.; Kaplan, L.; Kim, R.; Szep, A.; Smith, A. M.

    2015-01-30

    Here we report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneousmore » detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4m-1.« less

  5. Variations of operations and noise of semiconductor lasers subject to optical feedback with nonlinear gain and nonradiative recombination

    SciTech Connect (OSTI)

    Abdulrhmann, S.; Al-Hossain, A.

    2015-03-30

    Influence of the nonlinear gain (NLG) and nonradiative recombination life time ratio (NRRLTR) on the rout to chaos and noise characteristics of semiconductor lasers (SLs) subject to optical feedback (OFB) are investigated. The analyses are performed in terms of the temporal trajectory of the photon numbers, bifurcation diagrams and relative intensity noise (RIN). Variations of the fluctuations of the photon number are statistically analyzed. The corresponding frequency dependence of RIN is characterized. The simulation results show that, NLG and NRRLTR can cause significant changes in the rout to chaos of the SLs and probability distribution of the photon numbers. We found that the value of the OFB rate at which the transition from CW to periodic oscillation (PO) or chaos state occur increases, as the value of the NLG/ NRRLTR is increased/decreased. The RIN is found to be suppressed when the laser is operated in CW or PO region and at relatively higher/lower values of the NLG/NRRLTR. We believe that, the instability of the SLs can be reduced by operating it under OFB and by increasing/decreasing the values of the NLG/NRRLTR parameter.

  6. Mesoscale Engineering of Nanocomposite Nonlinear Optical Materials

    SciTech Connect (OSTI)

    Afonso, C.N.; Feldman, L.C.; Gonella, F.; Haglund, R.F.; Luepke, G.; Magruder, R.H.; Mazzoldi, P.; Osborne, D.H.; Solis, J.; Zuhr, R.A.

    1999-11-01

    Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have ail been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to ask what is happening at nanoscale dimensions. Systems integration of complex nonlinear optical materials requires that the mesoscale materials science be well understood within the context of device structures. We discuss the effects of beam energy and energy density on quantum-dot size and spatial distribution, thermal conductivity, quantum-dot composition, crystallinity and defects - and, in turn, on the third-order optical susceptibility of the composite material. Examples from recent work in our laboratories are used to illustrate these effects.

  7. Integrated resonant micro-optical gyroscope and method of fabrication

    DOE Patents [OSTI]

    Vawter, G. Allen; Zubrzycki, Walter J.; Guo, Junpeng; Sullivan, Charles T.

    2006-09-12

    An integrated optic gyroscope is disclosed which is based on a photonic integrated circuit (PIC) having a bidirectional laser source, a pair of optical waveguide phase modulators and a pair of waveguide photodetectors. The PIC can be connected to a passive ring resonator formed either as a coil of optical fiber or as a coiled optical waveguide. The lasing output from each end of the bidirectional laser source is phase modulated and directed around the passive ring resonator in two counterpropagating directions, with a portion of the lasing output then being detected to determine a rotation rate for the integrated optical gyroscope. The coiled optical waveguide can be formed on a silicon, glass or quartz substrate with a silicon nitride core and a silica cladding, while the PIC includes a plurality of III V compound semiconductor layers including one or more quantum well layers which are disordered in the phase modulators and to form passive optical waveguides.

  8. Resonant second harmonic generation in a gallium nitride two-dimensional photonic crystal on silicon

    SciTech Connect (OSTI)

    Zeng, Y.; Roland, I.; Checoury, X.; Han, Z.; El Kurdi, M.; Sauvage, S.; Boucaud, P.; Gayral, B.; Brimont, C.; Guillet, T.; Mexis, M.; Semond, F.

    2015-02-23

    We demonstrate second harmonic generation in a gallium nitride photonic crystal cavity embedded in a two-dimensional free-standing photonic crystal platform on silicon. The photonic crystal nanocavity is optically pumped with a continuous-wave laser at telecom wavelengths in the transparency window of the nitride material. The harmonic generation is evidenced by the spectral range of the emitted signal, the quadratic power dependence vs. input power, and the spectral dependence of second harmonic signal. The harmonic emission pattern is correlated to the harmonic polarization generated by the second-order nonlinear susceptibilities χ{sub zxx}{sup (2)}, χ{sub zyy}{sup (2)} and the electric fields of the fundamental cavity mode.

  9. High-speed quantum-random number generation by continuous measurement of arrival time of photons

    SciTech Connect (OSTI)

    Yan, Qiurong; Zhao, Baosheng; Hua, Zhang; Liao, Qinghong; Yang, Hao

    2015-07-15

    We demonstrate a novel high speed and multi-bit optical quantum random number generator by continuously measuring arrival time of photons with a common starting point. To obtain the unbiased and post-processing free random bits, the measured photon arrival time is converted into the sum of integral multiple of a fixed period and a phase time. Theoretical and experimental results show that the phase time is an independent and uniform random variable. A random bit extraction method by encoding the phase time is proposed. An experimental setup has been built and the unbiased random bit generation rate could reach 128 Mb/s, with random bit generation efficiency of 8 bits per detected photon. The random numbers passed all tests in the statistical test suite.

  10. A 1-D dusty plasma photonic crystal

    SciTech Connect (OSTI)

    Mitu, M. L.; Ticoş, C. M.; Toader, D.; Banu, N.; Scurtu, A.; Department of Physics, University of Bucharest, 077125 Bucharest

    2013-09-21

    It is demonstrated numerically that a 1-D plasma crystal made of micron size cylindrical dust particles can, in principle, work as a photonic crystal for terahertz waves. The dust rods are parallel to each other and arranged in a linear string forming a periodic structure of dielectric-plasma regions. The dispersion equation is found by solving the waves equation with the boundary conditions at the dust-plasma interface and taking into account the dielectric permittivity of the dust material and plasma. The wavelength of the electromagnetic waves is in the range of a few hundred microns, close to the interparticle separation distance. The band gaps of the 1-D plasma crystal are numerically found for different types of dust materials, separation distances between the dust rods and rod diameters. The distance between levitated dust rods forming a string in rf plasma is shown experimentally to vary over a relatively wide range, from 650 μm to about 1350 μm, depending on the rf power fed into the discharge.

  11. Assembly of quasicrystalline photonic heterostructures

    DOE Patents [OSTI]

    Grier, David G.; Roichman, Yael; Man, Weining; Chaikin, Paul Michael; Steinhardt, Paul Joseph

    2011-07-19

    A method and system for assembling a quasicrystalline heterostructure. A plurality of particles is provided with desirable predetermined character. The particles are suspended in a medium, and holographic optical traps are used to position the particles in a way to achieve an arrangement which provides a desired property.

  12. Assembly of quasicrystalline photonic heterostructures

    DOE Patents [OSTI]

    Grier, David G.; Roichman, Yael; Man, Weining; Chaikin, Paul Michael; Steinhardt, Paul Joseph

    2013-03-12

    A method and system for assembling a quasicrystalline heterostructure. A plurality of particles is provided with desirable predetermined character. The particles are suspended in a medium, and holographic optical traps are used to position the particles in a way to achieve an arrangement which provides a desired property.

  13. The large-area hybrid-optics CLAS12 RICH detector: Tests of innovative components

    SciTech Connect (OSTI)

    Contalbrigo, M.; Baltzell, N.; Benmokhtar, F.; Barion, L.; Cisbani, E.; El Alaoui, A.; Hafidi, K.; Hoek, M.; Kubarovsky, V.; Lagamba, L.; Lucherini, V.; Malaguti, R.; Mirazita, M.; Montgomery, R.; Movsisyan, A.; Musico, P.; Orecchini, D.; Orlandi, A.; Pappalardo, L.L.; Pereira, S.; Perrino, R.; Phillips, J.; Pisano, S.; Rossi, P.; Squerzanti, S.; Tomassini, S.; Turisini, M.; Viticchiè, A.

    2014-07-01

    A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab to study the 3D nucleon structure in the yet poorly explored valence region by deep-inelastic scattering, and to perform precision measurements in hadronization and hadron spectroscopy. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and densely packed and highly segmented photon detectors. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). The preliminary results of individual detector component tests and of the prototype performance at test-beams are reported here.

  14. New physics searches with photons in CDF

    SciTech Connect (OSTI)

    Sungwon Lee

    2004-05-24

    A brief review of searches for physics beyond the Standard Model with photons using the CDF detector at the Tevatron is given here. These include searches for supersymmetry, extra dimensions, excited electrons and W/Z+{gamma} production, as well as anomalous photon production. Recent results from CDF Run II experiment are presented, but some results from Run I are also reviewed.

  15. Photonic crystal scintillators and methods of manufacture

    DOE Patents [OSTI]

    Torres, Ricardo D.; Sexton, Lindsay T.; Fuentes, Roderick E.; Cortes-Concepcion, Jose

    2015-08-11

    Photonic crystal scintillators and their methods of manufacture are provided. Exemplary methods of manufacture include using a highly-ordered porous anodic alumina membrane as a pattern transfer mask for either the etching of underlying material or for the deposition of additional material onto the surface of a scintillator. Exemplary detectors utilizing such photonic crystal scintillators are also provided.

  16. Cascaded emission of linearly polarized single photons from positioned InP/GaInP quantum dots

    SciTech Connect (OSTI)

    Braun, T.; Unsleber, S.; Baumann, V.; Schneider, C.; Hfling, S.; Kamp, M.; Gschrey, M.; Rodt, S.; Reitzenstein, S.

    2013-11-04

    We report on the optical characterization of site-controlled InP/GaInP quantum dots (QDs). Spatially resolved low temperature cathodoluminescence proves the long-range ordering of the buried emitters, revealing a yield of ?90% of optically active, positioned QDs and a strong suppression of emitters on interstitial positions. The emission of single QDs shows a pronounced degree of linear polarization along the [0,?1,1] crystal axis with an average degree of polarization of 94%. Photon correlation measurements of the emission from a single QD indicate the single-photon character of the exciton and biexciton emission lines as well as the cascaded nature of the photon pair.

  17. Directed assembly of hybrid nanostructures using optically resonant nanotweezers

    SciTech Connect (OSTI)

    Erickson, David

    2015-09-09

    This represents the final report for this project. Over the course of the project we have made significant progress in photonically driven nano-assembly including: (1) demonstrating the first direct optical tweezer based manipulation of proteins, (2) the ability to apply optical angular torques to microtubuals and other rod-shaped microparticles, (3) direct assembly of hybrid nanostructures comprising of polymeric nanoparticles and carbon nanotubes and, (4) the ability to drive biological reactions (specifically protein aggregation) that are thermodynamically unfavorable by applying localized optical work. These advancements are described in the list of papers provided in section 2.0 of the below. Summary details are provided in prior year annual reports. We have two additional papers which will be submitted shortly based on the work done under this award. An updated publication list will be provided to the program manager when those are accepted. In this report, we report on a new advancement made in the final project year, which uses the nanotweezer technology to perform direct measurements of particle-surface interactions. Briefly, these measurements are important for characterizing the stability and behavior of colloidal and nanoparticle suspensions and current techniques are limited in their ability to measure piconewton scale interaction forces on sub-micrometer particles due to signal detection limits and thermal noise. In this project year we developed a new technique called “Nanophotonic Force Microscopy” which uses the localized region of exponentially decaying, near-field, light to confine small particles close to a surface. From the statistical distribution of the light intensity scattered by the particle the technique maps out the potential well of the trap and directly quantify the repulsive force between the nanoparticle and the surface. The major advantage of the technique is that it can measure forces and energy wells below the thermal noise

  18. Optical coupler

    DOE Patents [OSTI]

    Majewski, Stanislaw; Weisenberger, Andrew G.

    2004-06-15

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

  19. Optical analyzer

    DOE Patents [OSTI]

    Hansen, A.D.

    1987-09-28

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

  20. Optical memory

    DOE Patents [OSTI]

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

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

  1. Photon Science for Renewable Energy

    SciTech Connect (OSTI)

    Hussain, Zahid; Tamura, Lori; Padmore, Howard; Schoenlein, Bob; Bailey, Sue

    2010-03-31

    Our current fossil-fuel-based system is causing potentially catastrophic changes to our planet. The quest for renewable, nonpolluting sources of energy requires us to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels. Light-source facilities - the synchrotrons of today and the next-generation light sources of tomorrow - are the scientific tools of choice for exploring the electronic and atomic structure of matter. As such, these photon-science facilities are uniquely positioned to jump-start a global revolution in renewable and carbonneutral energy technologies. In these pages, we outline and illustrate through examples from our nation's light sources possible scientific directions for addressing these profound yet urgent challenges.

  2. Antenna coupled photonic wire lasers

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

    Reno, John L.; Kao, Tsung-Kao; Cai, Xiaowei; Lee, Alan W. M.; Hu, Qing

    2015-06-22

    Slope efficiency (SE) is an important performance metric for lasers. In conventional semiconductor lasers, SE can be optimized by careful designs of the facet (or the modulation for DFB lasers) dimension and surface. However, photonic wire lasers intrinsically suffer low SE due to their deep sub-wavelength emitting facets. Inspired by microwave engineering techniques, we show a novel method to extract power from wire lasers using monolithically integrated antennas. These integrated antennas significantly increase the effective radiation area, and consequently enhance the power extraction efficiency. When applied to wire lasers at THz frequency, we achieved the highest single-side slope efficiency (~450moremW/A) in pulsed mode for DFB lasers at 4 THz and a ~4x increase in output power at 3 THz compared with a similar structure without antennas. This work demonstrates the versatility of incorporating microwave engineering techniques into laser designs, enabling significant performance enhancements.less

  3. Tailorable 3D microfabrication for photonic applications: two-polymer microtransfer molding (proceedings paper)

    SciTech Connect (OSTI)

    Lee, Jae-Hwang; kim, Chang-Hwan; Constant, Kristen; Ho, Kai-Ming

    2006-02-28

    For photonic devices, extending beyond the planar regime to the third dimension can allow a higher degree of integration and novel functionalities for applications such as photonic crystals and integrated optical circuits. Although conventional photolithography can achieve both high quality and structural control, it is still costly and slow for three-dimensional (3D) fabrication. Moreover, as diverse functional polymers emerge, there is potential to develop new techniques for quick and economical fabrication of 3D structures. We present a 3D microfabrication technique based on the soft lithographic technique, called two-polymer microtransfer molding (2P-{micro}TM) to accomplish low cost, high structural fidelity and tailorable 3D microfabrication for polymers. Using 2P-{micro}TM, highly layered polymeric microstructures are achievable by stacking planar structures layer by layer. For increased processing control, the surface chemistry of the polymers is characterized as a function of changing ultraviolet dosage to optimize yield in layer transfer. We discuss the application of the 2P-{micro}TM to build polymer templates for woodpile photonic crystals, and demonstrate methods for converting the polymer templates to dielectric and metallic photonic crystal structures. Finally, we will show that 2P-{micro}TM is promising for fabricating 3D polymeric optical waveguides.

  4. National Ignition Facility & Photon Science What

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

    ... Because the precise alignment of NIF's laser beams is extremely important for successful ... Optics Inspection System NIF's final optics damage inspection system, when extended into ...

  5. Method of manufacturing flexible metallic photonic band gap structures, and structures resulting therefrom

    DOE Patents [OSTI]

    Gupta, Sandhya; Tuttle, Gary L.; Sigalas, Mihail; McCalmont, Jonathan S.; Ho, Kai-Ming

    2001-08-14

    A method of manufacturing a flexible metallic photonic band gap structure operable in the infrared region, comprises the steps of spinning on a first layer of dielectric on a GaAs substrate, imidizing this first layer of dielectric, forming a first metal pattern on this first layer of dielectric, spinning on and imidizing a second layer of dielectric, and then removing the GaAs substrate. This method results in a flexible metallic photonic band gap structure operable with various filter characteristics in the infrared region. This method may be used to construct multi-layer flexible metallic photonic band gap structures. Metal grid defects and dielectric separation layer thicknesses are adjusted to control filter parameters.

  6. Optical switch

    DOE Patents [OSTI]

    Reedy, Robert P.

    1987-01-01

    An optical switching device (10) is provided whereby light from a first glass fiber (16) or a second glass fiber (14) may be selectively transmitted into a third glass fiber (18). Each glass fiber is provided with a focusing and collimating lens system (26, 28, 30). In one mode of operation, light from the first glass fiber (16) is reflected by a planar mirror (36) into the third glass fiber (18). In another mode of operation, light from the second glass fiber (14) passes directly into the third glass fiber (18). The planar mirror (36) is attached to a rotatable table (32) which is rotated to provide the optical switching.

  7. Optical switch

    DOE Patents [OSTI]

    Reedy, R.P.

    1987-11-10

    An optical switching device is provided whereby light from a first glass fiber or a second glass fiber may be selectively transmitted into a third glass fiber. Each glass fiber is provided with a focusing and collimating lens system. In one mode of operation, light from the first glass fiber is reflected by a planar mirror into the third glass fiber. In another mode of operation, light from the second glass fiber passes directly into the third glass fiber. The planar mirror is attached to a rotatable table which is rotated to provide the optical switching. 3 figs.

  8. Computational Study and Analysis of Structural Imperfections in 1D and 2D Photonic Crystals

    SciTech Connect (OSTI)

    K.R. Maskaly

    2005-06-01

    Dielectric reflectors that are periodic in one or two dimensions, also known as 1D and 2D photonic crystals, have been widely studied for many potential applications due to the presence of wavelength-tunable photonic bandgaps. However, the unique optical behavior of photonic crystals is based on theoretical models of perfect analogues. Little is known about the practical effects of dielectric imperfections on their technologically useful optical properties. In order to address this issue, a finite-difference time-domain (FDTD) code is employed to study the effect of three specific dielectric imperfections in 1D and 2D photonic crystals. The first imperfection investigated is dielectric interfacial roughness in quarter-wave tuned 1D photonic crystals at normal incidence. This study reveals that the reflectivity of some roughened photonic crystal configurations can change up to 50% at the center of the bandgap for RMS roughness values around 20% of the characteristic periodicity of the crystal. However, this reflectivity change can be mitigated by increasing the index contrast and/or the number of bilayers in the crystal. In order to explain these results, the homogenization approximation, which is usually applied to single rough surfaces, is applied to the quarter-wave stacks. The results of the homogenization approximation match the FDTD results extremely well, suggesting that the main role of the roughness features is to grade the refractive index profile of the interfaces in the photonic crystal rather than diffusely scatter the incoming light. This result also implies that the amount of incoherent reflection from the roughened quarterwave stacks is extremely small. This is confirmed through direct extraction of the amount of incoherent power from the FDTD calculations. Further FDTD studies are done on the entire normal incidence bandgap of roughened 1D photonic crystals. These results reveal a narrowing and red-shifting of the normal incidence bandgap with

  9. Electromagnetic Wave Propagation in Two-Dimensional Photonic Crystals

    SciTech Connect (OSTI)

    Stavroula Foteinopoulou

    2003-12-12

    In this dissertation, they have undertaken the challenge to understand the unusual propagation properties of the photonic crystal (PC). The photonic crystal is a medium where the dielectric function is periodically modulated. These types of structures are characterized by bands and gaps. In other words, they are characterized by frequency regions where propagation is prohibited (gaps) and regions where propagation is allowed (bands). In this study they focus on two-dimensional photonic crystals, i.e., structures with periodic dielectric patterns on a plane and translational symmetry in the perpendicular direction. They start by studying a two-dimensional photonic crystal system for frequencies inside the band gap. The inclusion of a line defect introduces allowed states in the otherwise prohibited frequency spectrum. The dependence of the defect resonance state on different parameters such as size of the structure, profile of incoming source, etc., is investigated in detail. For this study, they used two popular computational methods in photonic crystal research, the Finite Difference Time Domain method (FDTD) and the Transfer Matrix Method (TMM). The results for the one-dimensional defect system are analyzed, and the two methods, FDTD and TMM, are compared. Then, they shift their attention only to periodic two-dimensional crystals, concentrate on their band properties, and study their unusual refractive behavior. Anomalous refractive phenomena in photonic crystals included cases where the beam refracts on the ''wrong'' side of the surface normal. The latter phenomenon, is known as negative refraction and was previously observed in materials where the wave vector, the electric field, and the magnetic field form a left-handed set of vectors. These materials are generally called left-handed materials (LHM) or negative index materials (NIM). They investigated the possibility that the photonic crystal behaves as a LHM, and how this behavior relates with the observed

  10. Optically switchable natural silk

    SciTech Connect (OSTI)

    Krasnov, Igor Müller, Martin; Krekiehn, Nicolai R.; Jung, Ulrich; Magnussen, Olaf M.; Krywka, Christina; Zillohu, Ahnaf U.; Strunskus, Thomas; Elbahri, Mady

    2015-03-02

    An optically active bio-material is created by blending natural silk fibers with photoisomerizable chromophore molecules—azobenzenebromide (AzBr). The material converts the energy of unpolarized light directly into mechanical work with a well-defined direction of action. The feasibility of the idea to produce optically driven microsized actuators on the basis of bio-material (silk) is proven. The switching behavior of the embedded AzBr molecules was studied in terms of UV/Vis spectroscopy. To test the opto-mechanical properties of the modified fibers and the structural changes they undergo upon optically induced switching, single fiber X-ray diffraction with a micron-sized synchrotron radiation beam was combined in situ with optical switching as well as with mechanical testing and monitoring. The crystalline regions of silk are not modified by the presence of the guest molecules, hence occupy only the amorphous part of the fibers. It is shown that chromophore molecules embedded into fibers can be reversibly switched between the trans and cis conformation by illumination with light of defined wavelengths. The host fibers respond to this switching with a variation of the internal stress. The amplitude of the mechanical response is independent of the applied external stress and its characteristic time is shorter than the relaxation time of the usual mechanical response of silk.

  11. Multiple soliton self-frequency shift cancellations in a temporally tailored photonic crystal fiber

    SciTech Connect (OSTI)

    Liu, Lai; Kang, Zhe; Li, Qing; Gao, Xuejian; Qin, Guanshi E-mail: wpqin@jlu.edu.cn; Qin, Weiping E-mail: wpqin@jlu.edu.cn; Liao, Meisong; Hu, Lili; Ohishi, Yasutake

    2014-11-03

    We report the generation of multiple soliton self-frequency shift cancellations in a temporally tailored tellurite photonic crystal fiber (PCF). The temporally regulated group velocity dispersion (GVD) is generated in the fiber by soliton induced optical Kerr effect. Two red-shifted dispersive waves spring up when two Raman solitons meet their own second zero-dispersion-wavelengths in the PCF. These results show how, through temporally tailored GVD, nonlinearities can be harnessed to generate unexpected effects.

  12. Methods and devices for maintaining a resonant wavelength of a photonic microresonator

    DOE Patents [OSTI]

    Jones, Adam; Zortman, William A.

    2015-07-14

    A photonic microresonator incorporates a localized heater element within a section of an optical bus waveguide that is in proximity to the resonator structure. The application of an adjustable control voltage to the heater element provides a localized change in the refractive index value of the bus waveguide, compensating for temperature-induced wavelength drift and maintaining a stabilized value of the microresonator's resonant wavelength.

  13. The Silicon Vertex Tracker for the Heavy Photon Search Experiment...

    Office of Scientific and Technical Information (OSTI)

    Silicon Vertex Tracker for the Heavy Photon Search Experiment Citation Details In-Document Search Title: The Silicon Vertex Tracker for the Heavy Photon Search Experiment Authors: ...

  14. Enhanced Absorption in 2D Materials Via Fano- Resonant Photonic...

    Office of Scientific and Technical Information (OSTI)

    Enhanced Absorption in 2D Materials Via Fano- Resonant Photonic Crystals Citation Details In-Document Search Title: Enhanced Absorption in 2D Materials Via Fano- Resonant Photonic ...

  15. Nano, photonic research gets boost from new 3-D visualization...

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

    of nanotechnology, particularly nanofilms, photonics and micro- and nano-electronics. ... Total External Reflection", published online this month in the journal Nature Photonics. ...

  16. Search for supersymmetry in electroweak production with photons...

    Office of Scientific and Technical Information (OSTI)

    supersymmetry in electroweak production with photons and large missing transverse energy ... Title: Search for supersymmetry in electroweak production with photons and large missing ...

  17. Kyungdong Photovoltaic Energy Corp KPE formerly Photon Semiconductor...

    Open Energy Info (EERE)

    formerly Photon Semiconductor Energy Jump to: navigation, search Name: Kyungdong Photovoltaic Energy Corp (KPE) (formerly Photon Semiconductor & Energy) Place: Changwon, South...

  18. Searches for new physics in photon final states (Conference)...

    Office of Scientific and Technical Information (OSTI)

    Conference: Searches for new physics in photon final states Citation Details In-Document Search Title: Searches for new physics in photon final states Authors: Loginov, Andrey ; ...

  19. Investigation of optical limiting properties of Aluminium nanoparticles prepared by pulsed laser ablation in different carrier media

    SciTech Connect (OSTI)

    Kuladeep, Rajamudili; Jyothi, L.; Narayana Rao, D.; Prakash, P.; Mayank Shekhar, S.; Durga Prasad, M.

    2013-12-28

    In this communication, we carried out the systematic investigation of nonlinear absorption and scattering properties of Aluminium nanoparticles (Al NPs) in various polar and non-polar solvents. Al NPs were synthesized with pulsed Nd:YAG laser operated at 1064 nm by ablating Al target in polar and non-polar liquid environment like chloroform, chlorobenzene, toluene, benzene, and carbon tetrachloride. Synthesized Al NPs colloids of various solvents differ in appearance and UV-Vis extinction spectra exhibit absorption in the UV region. The characterization of Al NPs performed by Transmission electron microscopy (TEM) studies reveal that NPs are made up of a well crystallized Al inner part (bright zone) embedded with an amorphous metal Al shell (dark region). Growth, aggregation, and precipitation mechanisms which influence the optical properties and stability of NPs are found to be related to the dipole moment of the surrounding liquid environment. The nonlinear absorption and scattering studies are performed by open aperture Z-scan technique with 532 nm under nanosecond pulse excitation. The Z-scan measurements are fitted theoretically to estimate both two-photon absorption (TPA) and nonlinear scattering (NLS) coefficients. In polar solvents like chlorobenzene, chloroform synthesized Al NPs exhibited higher TPA, NLS coefficient values, and lower optical limiting threshold values in comparison with partially polar solvent like toluene and non-polar solvents like benzene and carbontetrachloride. These results indicate the potential use of Al NPs as a versatile optical limiting material.

  20. Enhanced four-wave mixing in graphene-silicon slow-light photonic crystal waveguides

    SciTech Connect (OSTI)

    Zhou, Hao E-mail: tg2342@columbia.edu; Gu, Tingyi E-mail: tg2342@columbia.edu McMillan, James F.; Wong, Chee Wei E-mail: tg2342@columbia.edu; Petrone, Nicholas; Zande, Arend van der; Hone, James C.; Yu, Mingbin; Lo, Guoqiang; Kwong, Dim-Lee; Feng, Guoying; Zhou, Shouhuan

    2014-09-01

    We demonstrate the enhanced four-wave mixing of monolayer graphene on slow-light silicon photonic crystal waveguides. 200-μm interaction length, a four-wave mixing conversion efficiency of −23 dB is achieved in the graphene-silicon slow-light hybrid, with an enhanced 3-dB conversion bandwidth of about 17 nm. Our measurements match well with nonlinear coupled-mode theory simulations based on the measured waveguide dispersion, and provide an effective way for all-optical signal processing in chip-scale integrated optics.

  1. Coherent manipulation of spin-wave vector for polarization of photons in an atomic ensemble

    SciTech Connect (OSTI)

    Li Shujing; Xu Zhongxiao; Zheng Haiyan; Zhao Xingbo; Wu Yuelong; Wang Hai; Xie Changde; Peng Kunchi [State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006 (China)

    2011-10-15

    We experimentally demonstrate the manipulation of two orthogonal components of a spin wave in an atomic ensemble. Based on Raman two-photon transition and Larmor spin precession induced by magnetic field pulses, the coherent rotations between the two components of the spin wave are controllably achieved. Successively, the two manipulated spin-wave components are mapped into two orthogonal polarized optical emissions. By measuring Ramsey fringes of the retrieved optical signals, the {pi}/2-pulse fidelity of {approx}96% is obtained. The presented manipulation scheme can be used to build an arbitrary rotation for qubit operations in quantum information processing based on atomic ensembles.

  2. Controllable spiking patterns in long-wavelength vertical cavity surface emitting lasers for neuromorphic photonics systems

    SciTech Connect (OSTI)

    Hurtado, Antonio; Javaloyes, Julien

    2015-12-14

    Multiple controllable spiking patterns are achieved in a 1310 nm Vertical-Cavity Surface Emitting Laser (VCSEL) in response to induced perturbations and for two different cases of polarized optical injection, namely, parallel and orthogonal. Furthermore, reproducible spiking responses are demonstrated experimentally at sub-nanosecond speed resolution and with a controlled number of spikes fired. This work opens therefore exciting research avenues for the use of VCSELs in ultrafast neuromorphic photonic systems for non-traditional computing applications, such as all-optical binary-to-spiking format conversion and spiking information encoding.

  3. Electro-refractive photonic device

    DOE Patents [OSTI]

    Zortman, William A.; Watts, Michael R.

    2015-06-09

    The various technologies presented herein relate to phase shifting light to facilitate any of light switching, modulation, amplification, etc. Structures are presented where a second layer is juxtaposed between a first layer and a third layer with respective doping facilitating formation of p-n junctions at the interface between the first layer and the second layer, and between the second layer and the third layer. Application of a bias causes a carrier concentration change to occur at the p-n junctions which causes a shift in the effective refractive index per incremental change in an applied bias voltage. The effective refractive index enhancement can occur in both reverse bias and forward bias. The structure can be incorporated into a waveguide, an optical resonator, a vertical junction device, a horizontal junction device, a Mach-Zehnder interferometer, a tuneable optical filter, etc.

  4. Heralding efficiency and correlated-mode coupling of near-IR fiber-coupled photon pairs

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

    Dixon, P. Ben; Rosenberg, Danna; Stelmakh, Veronika; Grein, Matthew E.; Bennink, Ryan S.; Dauler, Eric A.; Kerman, Andrew J.; Molnar, Richard J.; Wong, Franco N. C.

    2014-10-06

    We report on a systematic experimental study of heralding efficiency and generation rate of telecom-band infrared photon pairs generated by spontaneous parametric down-conversion and coupled to single mode optical fibers. We define the correlated-mode coupling efficiency--an inherent source efficiency--and explain its relation to heralding efficiency. For our experiment, we developed a reconfigurable computer controlled pump-beam and collection-mode optical apparatus which we used to measure the generation rate and correlated-mode coupling efficiency. The use of low-noise, high-efficiency superconducting-nanowire single-photon-detectors in this setup allowed us to explore focus configurations with low overall photon flux. The measured data agree well with theory andmore » we demonstrated a correlated-mode coupling efficiency of 97%±2%, which is the highest efficiency yet achieved for this type of system. These results confirm theoretical treatments and demonstrate that very high overall heralding efficiencies can, in principle, be achieved in quantum optical systems. We expect that these results and techniques will be widely incorporated into future systems that require, or benefit from, a high heralding efficiency.« less

  5. Heralding efficiency and correlated-mode coupling of near-IR fiber-coupled photon pairs

    SciTech Connect (OSTI)

    Dixon, P. Ben; Rosenberg, Danna; Stelmakh, Veronika; Grein, Matthew E.; Bennink, Ryan S.; Dauler, Eric A.; Kerman, Andrew J.; Molnar, Richard J.; Wong, Franco N. C.

    2014-10-06

    We report on a systematic experimental study of heralding efficiency and generation rate of telecom-band infrared photon pairs generated by spontaneous parametric down-conversion and coupled to single mode optical fibers. We define the correlated-mode coupling efficiency--an inherent source efficiency--and explain its relation to heralding efficiency. For our experiment, we developed a reconfigurable computer controlled pump-beam and collection-mode optical apparatus which we used to measure the generation rate and correlated-mode coupling efficiency. The use of low-noise, high-efficiency superconducting-nanowire single-photon-detectors in this setup allowed us to explore focus configurations with low overall photon flux. The measured data agree well with theory and we demonstrated a correlated-mode coupling efficiency of 97%±2%, which is the highest efficiency yet achieved for this type of system. These results confirm theoretical treatments and demonstrate that very high overall heralding efficiencies can, in principle, be achieved in quantum optical systems. We expect that these results and techniques will be widely incorporated into future systems that require, or benefit from, a high heralding efficiency.

  6. Photon and neutrino spectra of time-dependent photospheric models of gamma-ray bursts

    SciTech Connect (OSTI)

    Asano, K. [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan); Mszros, P., E-mail: asanok@icrr.u-tokyo.ac.jp, E-mail: nnp@astro.psu.edu [Department of Astronomy and Astrophysics, Department of Physics, Center for Particle and Gravitational Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2013-09-01

    Thermal photons from the photosphere may be the primary source of the observed prompt emission of gamma-ray bursts (GRBs). In order to produce the observed non-thermal spectra, some kind of dissipation mechanism near the photosphere is required. In this paper we numerically simulate the evolution of the photon spectrum in a relativistically expanding shell with a time-dependent numerical code. We consider two basic models. One is a leptonic model, where a dissipation mechanism heats the thermal electrons maintaining their high temperature. The other model involves a cascade process induced by pp(pn)-collisions which produce high-energy electrons, modify the thermal spectrum, and emit neutrinos. The qualitative properties of the photon spectra are mainly determined by the optical depth at which the dissipation mechanism sets in. Too large optical depths lead to a broad and curved spectrum contradicting the observations, while for optical depths smaller than unity the spectral hardness becomes softer than observed. A significant shift of the spectral peak energy to higher energies due to a large energy injection can lead to an overly broad spectral shape. We show ideal parameter ranges for which these models are able to reproduce the observed spectra. For the pn-collision model, the neutrino fluence in the 10100 GeV range is well above the atmospheric neutrino fluence, but its detection is challenging for presently available detectors.

  7. Heralding efficiency and correlated-mode coupling of near-IR fiber coupled photon pairs

    SciTech Connect (OSTI)

    Dixon, P. Ben; Rosenberg, Danna; Stelmakh, Veronika; Grein, Matthew E.; Bennink, Ryan S; Dauler, Eric A.; Kerman, Andrew J.; Molnar, Richard J.; Wong, Franco N. C.

    2014-01-01

    We report on a systematic experimental study of heralding efficiency and generation rate of telecom-band infrared photon pairs generated by spontaneous parametric down-conversion and coupled to single mode optical fibers. We define the correlated-mode coupling efficiency--an inherent source efficiency--and explain its relation to heralding efficiency. For our experiment, we developed a reconfigurable computer controlled pump-beam and collection-mode optical apparatus which we used to measure the generation rate and correlated-mode coupling efficiency. The use of low-noise, high-efficiency superconducting-nanowire single-photon-detectors in this setup allowed us to explore focus configurations with low overall photon flux. The measured data agree well with theory and we demonstrated a correlated-mode coupling efficiency of 97 +-2%, which is the highest efficiency yet achieved for this type of system. These results confirm theoretical treatments and demonstrate that very high overall heralding efficiencies can, in principle, be achieved in quantum optical systems. It is expected that these results and techniques will be widely incorporated into future systems that require, or benefit from, a high heralding efficiency.

  8. Wave propagation in photonic crystals and metamaterials: Surface waves, nonlinearity and chirality

    SciTech Connect (OSTI)

    Wang, Bingnan

    2009-12-03

    Photonic crystals and metamaterials, both composed of artificial structures, are two interesting areas in electromagnetism and optics. New phenomena in photonic crystals and metamaterials are being discovered, including some not found in natural materials. This thesis presents my research work in the two areas. Photonic crystals are periodically arranged artificial structures, mostly made from dielectric materials, with period on the same order of the wavelength of the working electromagnetic wave. The wave propagation in photonic crystals is determined by the Bragg scattering of the periodic structure. Photonic band-gaps can be present for a properly designed photonic crystal. Electromagnetic waves with frequency within the range of the band-gap are suppressed from propagating in the photonic crystal. With surface defects, a photonic crystal could support surface modes that are localized on the surface of the crystal, with mode frequencies within the band-gap. With line defects, a photonic crystal could allow the propagation of electromagnetic waves along the channels. The study of surface modes and waveguiding properties of a 2D photonic crystal will be presented in Chapter 1. Metamaterials are generally composed of artificial structures with sizes one order smaller than the wavelength and can be approximated as effective media. Effective macroscopic parameters such as electric permittivity {epsilon}, magnetic permeability {mu} are used to characterize the wave propagation in metamaterials. The fundamental structures of the metamaterials affect strongly their macroscopic properties. By designing the fundamental structures of the metamaterials, the effective parameters can be tuned and different electromagnetic properties can be achieved. One important aspect of metamaterial research is to get artificial magnetism. Metallic split-ring resonators (SRRs) and variants are widely used to build magnetic metamaterials with effective {mu} < 1 or even {mu} < 0. Varactor

  9. Modification of Thermal Emission via Metallic Photonic Crystals

    SciTech Connect (OSTI)

    Norris, David J.; Stein, Andreas; George, Steven M.

    2012-07-30

    Photonic crystals are materials that are periodically structured on an optical length scale. It was previously demonstrated that the glow, or thermal emission, of tungsten photonic crystals that have a specific structure - known as the 'woodpile structure' - could be modified to reduce the amount of infrared radiation from the material. This ability has implications for improving the efficiency of thermal emission sources and for thermophotovoltaic devices. The study of this effect had been limited because the fabrication of metallic woodpile structures had previously required a complex fabrication process. In this project we pursued several approaches to simplify the fabrication of metallic photonic crystals that are useful for modification of thermal emission. First, we used the self-assembly of micrometer-scale spheres into colloidal crystals known as synthetic opals. These opals can then be infiltrated with a metal and the spheres removed to obtain a structure, known as an inverse opal, in which a three-dimensional array of bubbles is embedded in a film. Second, we used direct laser writing, in which the focus of an infrared laser is moved through a thin film of photoresist to form lines by multiphoton polymerization. Proper layering of such lines can lead to a scaffold with the woodpile structure, which can be coated with a refractory metal. Third, we explored a completely new approach to modified thermal emission - thin metal foils that contain a simple periodic surface pattern, as shown in Fig. 1. When such a foil is heated, surface plasmons are excited that propagate along the metal interface. If these waves strike the pattern, they can be converted into thermal emission with specific properties.

  10. Optically pumped isotopic ammonia laser system

    DOE Patents [OSTI]

    Buchwald, Melvin I.; Jones, Claude R.; Nelson, Leonard Y.

    1982-01-01

    An optically pumped isotopic ammonia laser system which is capable of producing a plurality of frequencies in the middle infrared spectral region. Two optical pumping mechanisms are disclosed, i.e., pumping on R(J) and lasing on P(J) in response to enhancement of rotational cascade lasing including stimulated Raman effects, and, pumping on R(J) and lasing on P(J+2). The disclosed apparatus for optical pumping include a hole coupled cavity and a grating coupled cavity.

  11. Deterministic and cascadable conditional phase gate for photonic qubits

    SciTech Connect (OSTI)

    Chudzicki, Christopher; Chuang, Isaac; Shapiro, Jeffrey H.

    2014-12-04

    Previous analyses of conditional ?{sub NL}-phase gates for photonic qubits that treat crossphase modulation (XPM) in a causal, multimode, quantum field setting suggest that a large (?? rad) nonlinear phase shift is always accompanied by fidelity-degrading noise [J. H. Shapiro, Phys. Rev. A 73, 062305 (2006); J. Gea-Banacloche, Phys. Rev. A 81, 043823 (2010)]. Using an atomic V-system to model an XPM medium, we present a conditional phase gate that, for sufficiently small nonzero ?{sub NL}, has high fidelity. The gate is made cascadable by using a special measurement, principal mode projection, to exploit the quantum Zeno effect and preclude the accumulation of fidelity-degrading departures from the principal-mode Hilbert space when both control and target photons illuminate the gate. The nonlinearity of the V-system we study is too weak for this particular implementation to be practical. Nevertheless, the idea of cascading through principal mode projection is of potential use to overcome fidelity degrading noise for a wide variety of nonlinear optical primitive gates.

  12. A bunch clock for the Advanced Photon Source

    SciTech Connect (OSTI)

    Lenkszus, F.R.; Laird, R.J.

    1997-06-01

    A bunch clock timing module has been developed for use by Advanced Photon Source beamlines. The module provides bunch pattern and timing information that can be used to trigger beamline data collection equipment. The module is fully integrated into the control system software (EPICS) which automatically loads it with the storage ring fill pattern at injection time. Fast timing outputs (1 ns FWHM) for each stored bunch are generated using the storage ring low-level rf and revolution clock as input references. Fiber-optic-based transmitters and receivers are used to transmit a 352-MHz low-level rf reference to distributed bunch clock modules. The bunch clock module is a single-width VME module and may be installed in a VME crate located near beamline instrumentation. A prototype has been in use on the SRI CAT beamline for over a year. The design and integration into the control system timing software along with measured performance results are presented.

  13. Heavy flavor production from photons and hadrons

    SciTech Connect (OSTI)

    Heusch, C.A.

    1982-01-01

    The present state of the production and observation of hadrons containing heavy quarks or antiquarks as valence constituents, in reactions initiated by real and (space-like) virtual photon or by hadron beams is discussed. Heavy flavor production in e/sup +/e/sup -/ annihilation, which is well covered in a number of recent review papers is not discussed, and similarly, neutrino production is omitted due to the different (flavor-changing) mechanisms that are involved in those reactions. Heavy flavors from spacelike photons, heavy flavors from real photons, and heavy flavors from hadron-hadron collisions are discussed. (WHK)

  14. Instabilities and chaos in quantum optics II; Proceedings of the NATO Advanced Study Institute, Il Ciocco, Italy, June 28-July 7, 1987

    SciTech Connect (OSTI)

    Abraham, N.B.; Arecchi, F.T.; Lugiato, L.A.

    1988-01-01

    The following topics are considered: laser and maser instabilities, classical and quantum noise, transverse effects, dynamics in optical bistability and nonlinear optical media, and methods of analysis in nonlinear dynamics. Particular papers are presented on multistability and chaos in a two-photon microscopic maser, quantum chaos in quantum optics, spatial chaos in bistable optical arrays, four-wave mixing and dynamics, and bifurcation problems in nonlinear optics.

  15. Noise spectroscopy of an optical microresonator

    SciTech Connect (OSTI)

    Kozlov, G. G.

    2013-05-15

    The noise spectrum is calculated for the intensity of light transmitted through an optical microresonator whose thickness experiences thermal oscillations. The noise spectrum reveals a maximum at the frequency of an acoustic mode localized in the optical microresonator and depends on the size of the illuminated region. The noise intensity estimates show that it can be detected by the modern noise spectroscopy technique.

  16. Photon-in photon-out hard X-ray spectroscopy at the Linac Coherent Light Source

    SciTech Connect (OSTI)

    Alonso-Mori, Roberto; Sokaras, Dimosthenis; Zhu, Diling; Kroll, Thomas; Chollet, Mathieu; Feng, Yiping; Glownia, James M.; Kern, Jan; Lemke, Henrik T.; Nordlund, Dennis; Robert, Aymeric; Sikorski, Marcin; Song, Sanghoon; Weng, Tsu -Chien; Bergmann, Uwe

    2015-04-15

    X-ray free-electron lasers (FELs) have opened unprecedented possibilities to study the structure and dynamics of matter at an atomic level and ultra-fast timescale. Many of the techniques routinely used at storage ring facilities are being adapted for experiments conducted at FELs. In order to take full advantage of these new sources several challenges have to be overcome. They are related to the very different source characteristics and its resulting impact on sample delivery, X-ray optics, X-ray detection and data acquisition. Here it is described how photon-in photon-out hard X-ray spectroscopy techniques can be applied to study the electronic structure and its dynamics of transition metal systems with ultra-bright and ultra-short FEL X-ray pulses. In particular, some of the experimental details that are different compared with synchrotron-based setups are discussed and illustrated by recent measurements performed at the Linac Coherent Light Source.

  17. Photon-in photon-out hard X-ray spectroscopy at the Linac Coherent Light Source

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

    Alonso-Mori, Roberto; Sokaras, Dimosthenis; Zhu, Diling; Kroll, Thomas; Chollet, Mathieu; Feng, Yiping; Glownia, James M.; Kern, Jan; Lemke, Henrik T.; Nordlund, Dennis; et al

    2015-04-15

    X-ray free-electron lasers (FELs) have opened unprecedented possibilities to study the structure and dynamics of matter at an atomic level and ultra-fast timescale. Many of the techniques routinely used at storage ring facilities are being adapted for experiments conducted at FELs. In order to take full advantage of these new sources several challenges have to be overcome. They are related to the very different source characteristics and its resulting impact on sample delivery, X-ray optics, X-ray detection and data acquisition. Here it is described how photon-in photon-out hard X-ray spectroscopy techniques can be applied to study the electronic structure andmore » its dynamics of transition metal systems with ultra-bright and ultra-short FEL X-ray pulses. In particular, some of the experimental details that are different compared with synchrotron-based setups are discussed and illustrated by recent measurements performed at the Linac Coherent Light Source.« less

  18. Quantum Optics

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

    Quantum Optics - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear

  19. Optical analyzer

    DOE Patents [OSTI]

    Hansen, Anthony D.

    1989-01-01

    An optical analyzer (10) wherein a sample (19) of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter (20) is placed in a combustion tube (11), and light from a light source (14) is passed through the sample (19). The temperature of the sample (19) is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample (19) is detected (18) as the temperature is raised. A data processor (23), differentiator (28) and a two pen recorder (24) provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample (19). These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample (19). Additional information is obtained by repeating the run in different atmospheres and/or different rates of heating with other samples of the same particulate material collected on other filters.

  20. Introduction to APS | Advanced Photon Source

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

    Introduction to APS What is the APS? What is the APS? The Advanced Photon Source is a synchrotron light source that produces high-energy, high-brightness x-ray beams. The source is...

  1. Advanced Photon Source Upgrade Project - Energy

    ScienceCinema (OSTI)

    Gibson, Murray; Chamberlain, Jeff; Young, Linda

    2013-04-19

    An upgrade to the Advanced Photon Source (announced by DOE - http://go.usa.gov/ivZ) will help scientists better understand complex environments such as in catalytic reactions.

  2. Photon Science : SLAC National Accelerator Laboratory

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

    Affairs | Org Chart Photon Science Faculty Arthur I. Bienenstock * John Galayda Chi-Chang Kao Srinivas Raghu Gordon E. Brown, Jr. Siegfried Glenzer Young Lee David A. Reis Axel...

  3. A Further Understanding of Superconductivity | Advanced Photon...

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

    working at the U.S. Department of Energy Office of Science's Advanced Photon Source (APS). "There have been more than 60,000 papers published on high-temperature...

  4. Advanced Photon Source Upgrade Project - Materials

    ScienceCinema (OSTI)

    Gibbson, Murray;

    2013-04-19

    An upgrade to Advanced Photon Source announced by DOE - http://go.usa.gov/ivZ -- will help scientists break through bottlenecks in materials design in order to develop materials with desirable functions.

  5. Potential applications of concentrated solar photons

    SciTech Connect (OSTI)

    Not Available

    1991-01-01

    In 1989, the National Research Council formed a committee, upon the request of the Department of Energy (DOE), to assess potential applications of concentrated solar photons beyond the production of electricity. The committee interpreted the term applications to be those of commercial value, that is, applications in which the use of concentrated solar photons leads to a new product or process, creating a new market; cost reduction for an existing product or process; improvement in a product or process; or provision of a technical service. The goal of this study was to determine whether special advantages might result when concentrated solar photons are the source of energy for photochemical, photoelectrochemical, and thermal processes. The study undertook to assess the state of the art of potential applications, such as war and waste treatment. Other possible applications of solar photons, such as materials processing and solar pumping of lasers, also were considered. This work describes these applications.

  6. Enhanced Photon Recycling in Multijunction Solar Cells

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

    Ferreira, X. Li, E. Yablonovitch, a nd J .A. R ogers, " Device A rchitectures f or E nhanced Photon Recycling in Thin---Film MulQjuncQon Solar Cells." Adv. Energy M ater. (2014). ...

  7. Photon Source Parameters | Stanford Synchrotron Radiation Lightsource

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

    Photon Source Parameters Beam Lines by Techniques | Beam Lines by Number Beam Energy 3 GeV Injection Energy 3 GeV Current 300-500 mA Fill Pattern 270 bunches distributed in six...

  8. Fiber optic monitoring device

    DOE Patents [OSTI]

    Samborsky, James K.

    1993-01-01

    A device for the purpose of monitoring light transmissions in optical fibers comprises a fiber optic tap that optically diverts a fraction of a transmitted optical signal without disrupting the integrity of the signal. The diverted signal is carried, preferably by the fiber optic tap, to a lens or lens system that disperses the light over a solid angle that facilitates viewing. The dispersed light indicates whether or not the monitored optical fiber or system of optical fibers is currently transmitting optical information.

  9. MULTI-PHOTON PHOSPHOR FEASIBILITY RESEARCH

    SciTech Connect (OSTI)

    R. Graham; W. Chow

    2003-05-01

    Development of multi-photon phosphor materials for discharge lamps represents a goal that would achieve up to a doubling of discharge (fluorescent) lamp efficacy. This report reviews the existing literature on multi-photon phosphors, identifies obstacles in developing such phosphors, and recommends directions for future research to address these obstacles. To critically examine issues involved in developing a multi-photon phosphor, the project brought together a team of experts from universities, national laboratories, and an industrial lamp manufacturer. Results and findings are organized into three categories: (1) Multi-Photon Systems and Processes, (2) Chemistry and Materials Issues, and (3) Concepts and Models. Multi-Photon Systems and Processes: This category focuses on how to use our current understanding of multi-photon phosphor systems to design new phosphor systems for application in fluorescent lamps. The quickest way to develop multi-photon lamp phosphors lies in finding sensitizer ions for Gd{sup 3+} and identifying activator ions to red shift the blue emission from Pr{sup 3+} due to the {sup 1}S{sub 0} {yields} {sup 1}I{sub 6} transition associated with the first cascading step. Success in either of these developments would lead to more efficient fluorescent lamps. Chemistry and Materials Issues: The most promising multi-photon phosphors are found in fluoride hosts. However, stability of fluorides in environments typically found in fluorescent lamps needs to be greatly improved. Experimental investigation of fluorides in actual lamp environments needs to be undertaken while working on oxide and oxyfluoride alternative systems for backup. Concepts and Models: Successful design of a multi-photon phosphor system based on cascading transitions of Gd{sup 3+} and Pr{sup 3+} depends critically on how the former can be sensitized and the latter can sensitize an activator ion. Methods to predict energy level diagrams and Judd-Ofelt parameters of multi-photon

  10. Separating and combining single-mode and multimode optical beams

    DOE Patents [OSTI]

    Ruggiero, Anthony J; Masquelier, Donald A; Cooke, Jeffery B; Kallman, Jeffery S

    2013-11-12

    Techniques for combining initially separate single mode and multimode optical beams into a single "Dual Mode" fiber optic have been developed. Bi-directional propagation of two beams that are differentiated only by their mode profiles (i.e., wavefront conditions) is provided. The beams can be different wavelengths and or contain different modulation information but still share a common aperture. This method allows the use of conventional micro optics and hybrid photonic packaging techniques to produce small rugged packages suitable for use in industrial or military environments.

  11. Nano-engineering by optically directed self-assembly.

    SciTech Connect (OSTI)

    Furst, Eric; Dunn, Elissa; Park, Jin-Gyu; Brinker, C. Jeffrey; Sainis, Sunil; Merrill, Jason; Dufresne, Eric; Reichert, Matthew D.; Brotherton, Christopher M.; Bogart, Katherine Huderle Andersen; Molecke, Ryan A.; Koehler, Timothy P.; Bell, Nelson Simmons; Grillet, Anne Mary; Gorby, Allen D.; Singh, John; Lele, Pushkar; Mittal, Manish

    2009-09-01

    Lack of robust manufacturing capabilities have limited our ability to make tailored materials with useful optical and thermal properties. For example, traditional methods such as spontaneous self-assembly of spheres cannot generate the complex structures required to produce a full bandgap photonic crystals. The goal of this work was to develop and demonstrate novel methods of directed self-assembly of nanomaterials using optical and electric fields. To achieve this aim, our work employed laser tweezers, a technology that enables non-invasive optical manipulation of particles, from glass microspheres to gold nanoparticles. Laser tweezers were used to create ordered materials with either complex crystal structures or using aspherical building blocks.

  12. Power optics

    SciTech Connect (OSTI)

    Apollonov, V V

    2014-02-28

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it. The

  13. Angle-resolved photoemission spectroscopy with 9-eV photon-energy pulses generated in a gas-filled hollow-core photonic crystal fiber

    SciTech Connect (OSTI)

    Bromberger, H. Liu, H.; Chávez-Cervantes, M.; Gierz, I.; Ermolov, A.; Belli, F.; Abdolvand, A.; Russell, P. St. J.; Travers, J. C.; Calegari, F.; Li, M. T.; Lin, C. T.; Cavalleri, A.

    2015-08-31

    A recently developed source of ultraviolet radiation, based on optical soliton propagation in a gas-filled hollow-core photonic crystal fiber, is applied here to angle-resolved photoemission spectroscopy (ARPES). Near-infrared femtosecond pulses of only few μJ energy generate vacuum ultraviolet radiation between 5.5 and 9 eV inside the gas-filled fiber. These pulses are used to measure the band structure of the topological insulator Bi{sub 2}Se{sub 3} with a signal to noise ratio comparable to that obtained with high order harmonics from a gas jet. The two-order-of-magnitude gain in efficiency promises time-resolved ARPES measurements at repetition rates of hundreds of kHz or even MHz, with photon energies that cover the first Brillouin zone of most materials.

  14. Nonlinear stimulated Brillouin scattering based photonic signal processors

    SciTech Connect (OSTI)

    Minasian, Robert A.

    2014-10-06

    Recent new methods in photonic signal processing based on stimulated Brillouin scattering, that enable the realization of photonic mixers with high conversion efficiency, ultra-wide continuously tunable high-resolution microwave photonic filters and programmable switchable microwave photonic tunable filters, are presented. These processors provide new capabilities for the realisation of high-performance and high-resolution signal processing.

  15. Tamper-indicating quantum optical seals

    SciTech Connect (OSTI)

    Humble, Travis S; Williams, Brian P

    2015-01-01

    Confidence in the means for identifying when tampering occurs is critical for containment and surveillance technologies. Fiber-optic seals have proven especially useful for actively surveying large areas or inventories due to the extended transmission range and flexible layout of fiber. However, it is reasonable to suspect that an intruder could tamper with a fiber-optic sensor by accurately replicating the light transmitted through the fiber. In this contribution, we demonstrate a novel approach to using fiber-optic seals for safeguarding large-scale inventories with increased confidence in the state of the seal. Our approach is based on the use of quantum mechanical phenomena to offer unprecedented surety in the authentication of the seal state. In particular, we show how quantum entangled photons can be used to monitor the integrity of a fiber-optic cable - the entangled photons serve as active sensing elements whose non-local correlations indicate normal seal operation. Moreover, we prove using the quantum no-cloning theorem that attacks against the quantum seal necessarily disturb its state and that these disturbances are immediately detected. Our quantum approach to seal authentication is based on physical principles alone and does not require the use of secret or proprietary information to ensure proper operation. We demonstrate an implementation of the quantum seal using a pair of entangled photons and we summarize our experimental results including the probability of detecting intrusions and the overall stability of the system design. We conclude by discussing the use of both free-space and fiber-based quantum seals for surveying large areas and inventories.

  16. Regional Partnerships

    Broader source: Energy.gov [DOE]

    DOE has created a network of seven Regional Carbon Sequestration Partnerships (RCSPs) to help develop the technology, infrastructure, and regulations to implement large-scale CO2 storage (also...

  17. Region Overview

    Energy Savers [EERE]

    ... Power Plants: 1,858 (30% total U.S.) Coal-fired: 167 (30% total U.S.) Petroleum-fired: ... leading cause of natural gas processing plant disruptions in the East Coast Region from ...

  18. Region Overview

    Energy Savers [EERE]

    Power Plants: 666 (11% total U.S.) Coal-fired: 46 (8% total U.S.) Petroleum-fired: 39 ... leading cause of natural gas processing plant disruptions in the Gulf Coast Region from ...

  19. Region Overview

    Energy Savers [EERE]

    Power Plants: 429 (8% total U.S.) Coal-fired: 46 (8% total U.S.) Petroleum-fired: 26 ... leading cause of natural gas processing plant disruptions in the Rocky Mountain Region ...

  20. Region Overview

    Energy Savers [EERE]

    ... Power Plants: 2,006 (30% total U.S.) Coal-fired: 274 (49% total U.S.) Petroleum-fired: ... leading cause of natural gas processing plant disruptions in the Midwest region from ...

  1. Region Overview

    Energy Savers [EERE]

    Power Plants: 1,407 (24% total U.S.) Coal-fired: 24 (4% total U.S.) Petroleum-fired: 131 ... leading cause of natural gas processing plant disruptions in the West Coast Region's ...

  2. Determinations of photon spectra. Master's thesis

    SciTech Connect (OSTI)

    Wannigman, D.L.

    1989-01-01

    A method is developed to unfold photon spectra from measurements obtained with a sodium iodide counting system. A response matrix is computed by combining photon cross sections with probability distributions of path lengths for incident and internally generated photons in the energy range 0-2.8 MeV. This matrix is inverted and multiplied by a measured pulse height spectrum to obtain the photon energy distribution incident upon the detector. This deconvolution procedure provides improved information about the energy continuum of incident photons and can enhanced the identification of discrete gamma energies. Experiments were performed to verify the unfolding methodology and to evaluate the feasibility and accuracy of this technique. Measured spectra were acquired from indoor and outdoor environments and unfolded. The results show that measured spectra overestimate the number of photons below 240 keV by up to 30 %. When the total exposure was calculated directly from the measured spectra, the low energy contribution was overestimated by a factor of two. This may have implications on the interpretation and calibration of energy dependent dosimeters used for occupational and environmental monitoring.

  3. Parallel optical sampler

    DOE Patents [OSTI]

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

    2014-05-20

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

  4. Optical microphone

    DOE Patents [OSTI]

    Veligdan, James T.

    2000-01-11

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

  5. Optical devices

    DOE Patents [OSTI]

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

    2010-07-13

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

  6. Optical microfluidics

    SciTech Connect (OSTI)

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

    2004-09-27

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

  7. Photon-axion conversion as a mechanism for supernova dimming: Limits from CMB spectral distortion

    SciTech Connect (OSTI)

    Mirizzi, Alessandro; Raffelt, Georg G.; Serpico, Pasquale D.

    2005-07-15

    Axion-photon conversion induced by intergalactic magnetic fields has been proposed as an explanation for the dimming of distant supernovae of type Ia (SNe Ia) without cosmic acceleration. The effect depends on the intergalactic electron density n{sub e} as well as the B-field strength and domain size. We show that for n{sub e} < or approx. 10{sup -9} cm{sup -3} the same mechanism would cause excessive spectral distortion of the cosmic microwave background (CMB). This small-n{sub e} parameter region had been left open by the most restrictive previous constraints based on the dispersion of quasar (QSO) spectra. The combination of CMB and QSO limits suggests that the photon-axion conversion mechanism can only play a subleading role for SN Ia dimming. A combined analysis of all the observables affected by the photon-axion oscillations would be required to give a final verdict on the viability of this model.

  8. Probing CP violation in $$h\\rightarrow\\gamma\\gamma$$ with converted photons

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

    Bishara, Fady; Grossman, Yuval; Harnik, Roni; Robinson, Dean J.; Shu, Jing; Zupan, Jure

    2014-04-11

    We study Higgs diphoton decays, in which both photons undergo nuclear conversion to electron- positron pairs. The kinematic distribution of the two electron-positron pairs may be used to probe the CP violating (CPV) coupling of the Higgs to photons, that may be produced by new physics. Detecting CPV in this manner requires interference between the spin-polarized helicity amplitudes for both conversions. We derive leading order, analytic forms for these amplitudes. In turn, we obtain compact, leading-order expressions for the full process rate. While performing experiments involving photon conversions may be challenging, we use the results of our analysis to constructmore » experimental cuts on certain observables that may enhance sensitivity to CPV. We show that there exist regions of phase space on which sensitivity to CPV is of order unity. As a result, the statistical sensitivity of these cuts are verified numerically, using dedicated Monte-Carlo simulations.« less

  9. Optical interconnect assembly

    DOE Patents [OSTI]

    Laughlin, Daric; Abel, Philip

    2015-06-09

    An optical assembly includes a substrate with a first row of apertures and a second row of apertures. A first optical die includes a first plurality of optical transducer elements and is mounted on the substrate such that an optical signal interface of each transducer element is aligned with an aperture of the first row of optical apertures. A second optical die includes a second plurality of optical transducer elements and is mounted on the substrate such that an optical signal interface of each of the second plurality of optical transducer elements is aligned with an aperture of the second row of optical apertures. A connector configured to mate with the optical assembly supports a plurality of optical fibers. A terminal end of each optical fiber protrudes from the connector and extends into one of the apertures when the connector is coupled with the optical assembly.

  10. Opto-electronic device for frequency standard generation and terahertz-range optical demodulation based on quantum interference

    DOE Patents [OSTI]

    Georgiades, N.P.; Polzik, E.S.; Kimble, H.J.

    1999-02-02

    An opto-electronic system and technique for comparing laser frequencies with large frequency separations, establishing new frequency standards, and achieving phase-sensitive detection at ultra high frequencies are disclosed. Light responsive materials with multiple energy levels suitable for multi-photon excitation are preferably used for nonlinear mixing via quantum interference of different excitation paths affecting a common energy level. Demodulation of a carrier with a demodulation frequency up to 100`s THZ can be achieved for frequency comparison and phase-sensitive detection. A large number of materials can be used to cover a wide spectral range including the ultra violet, visible and near infrared regions. In particular, absolute frequency measurement in a spectrum from 1.25 {micro}m to 1.66 {micro}m for fiber optics can be accomplished with a nearly continuous frequency coverage. 7 figs.

  11. Opto-electronic device for frequency standard generation and terahertz-range optical demodulation based on quantum interference

    DOE Patents [OSTI]

    Georgiades, Nikos P.; Polzik, Eugene S.; Kimble, H. Jeff

    1999-02-02

    An opto-electronic system and technique for comparing laser frequencies with large frequency separations, establishing new frequency standards, and achieving phase-sensitive detection at ultra high frequencies. Light responsive materials with multiple energy levels suitable for multi-photon excitation are preferably used for nonlinear mixing via quantum interference of different excitation paths affecting a common energy level. Demodulation of a carrier with a demodulation frequency up to 100's THZ can be achieved for frequency comparison and phase-sensitive detection. A large number of materials can be used to cover a wide spectral range including the ultra violet, visible and near infrared regions. In particular, absolute frequency measurement in a spectrum from 1.25 .mu.m to 1.66 .mu.m for fiber optics can be accomplished with a nearly continuous frequency coverage.

  12. Enhanced optical nonlinearities in the near-infrared using III-nitride heterostructures coupled to metamaterials

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

    Wolf, Omri; Allerman, Andrew A.; Ma, Xuedan; Wendt, Joel R.; Song, Alex Y.; Shaner, Eric A.; Brener, Igal

    2015-10-15

    We use planar metamaterial resonators to enhance, by more than two orders of magnitude, the optical second harmonic generation, in the near infrared, obtained from intersubband transitions in III-Nitride heterostructures. The improvement arises from two factors: employing an asymmetric double quantum well design and aligning the resonators’ cross-polarized resonances with the intersubband transition energies. The resulting nonlinear metamaterial operates at wavelengths where single photon detection is available, and represents a new class of sources for quantum photonics related phenomena.

  13. Photonic devices on planar and curved substrates and methods for fabrication thereof

    DOE Patents [OSTI]

    Bartl, Michael H.; Barhoum, Moussa; Riassetto, David

    2016-08-02

    A versatile and rapid sol-gel technique for the fabrication of high quality one-dimensional photonic bandgap materials. For example, silica/titania multi-layer materials may be fabricated by a sol-gel chemistry route combined with dip-coating onto planar or curved substrate. A shock-cooling step immediately following the thin film heat-treatment process is introduced. This step was found important in the prevention of film crack formation--especially in silica/titania alternating stack materials with a high number of layers. The versatility of this sol-gel method is demonstrated by the fabrication of various Bragg stack-type materials with fine-tuned optical properties by tailoring the number and sequence of alternating layers, the film thickness and the effective refractive index of the deposited thin films. Measured optical properties show good agreement with theoretical simulations confirming the high quality of these sol-gel fabricated optical materials.

  14. Measuring W photon couplings in a 500 GeV e sup + e sup - collider

    SciTech Connect (OSTI)

    Yehudai, E.

    1991-08-01

    The Standard Model gives definite predictions for the W-photon couplings. Measuring them would test an important ingredient of the model. In this work we study the capability of a 500 GeV e{sup +}e{sup {minus}} collider to measure these couplings. We study the most general C and P conserving WW{lambda} vertex. This vertex contains two free parameters, {kappa} and {lambda}. We look at three processes: e{sup +}e{sup {minus}} {yields} W{sup +}W{sup {minus}}, e{lambda} {yields} W{nu} and {lambda}{lambda} {yields} W{sup +}W{sup {minus}}. For each process we present analytical expressions of helicity amplitudes for arbitrary values of {kappa} and {lambda}. We consider three different sources for the initial photon(s). The first two are breamsstrahlung and beamstrahlung (photon radiation induced by the collective fields of the opposite bunch). Both occur naturally in the collider environment. The third is a photon beam generated by scattering low energy laser light off a high energy electron beam. We examine potential observables for each process, calculating their sensitivity to {kappa} and {lambda}, and estimating the accuracy with which they can be measured. Assuming Standard Model values are actually measured, we present the region in the {kappa}-{lambda} plane to which the W couplings can be restricted with a given confidence level. We find that combining the three processes, one can measure {kappa} and {lambda} with accuracy of 0.01--0.02.

  15. Polymer lattices as mechanically tunable 3-dimensional photonic crystals operating in the infrared

    SciTech Connect (OSTI)

    Chernow, V. F.; Alaeian, H.; Dionne, J. A.; Greer, J. R.

    2015-09-07

    Broadly tunable photonic crystals in the near- to mid-infrared region could find use in spectroscopy, non-invasive medical diagnosis, chemical and biological sensing, and military applications, but so far have not been widely realized. We report the fabrication and characterization of three-dimensional tunable photonic crystals composed of polymer nanolattices with an octahedron unit-cell geometry. These photonic crystals exhibit a strong peak in reflection in the mid-infrared that shifts substantially and reversibly with application of compressive uniaxial strain. A strain of ∼40% results in a 2.2 μm wavelength shift in the pseudo-stop band, from 7.3 μm for the as-fabricated nanolattice to 5.1 μm when strained. We found a linear relationship between the overall compressive strain in the photonic crystal and the resulting stopband shift, with a ∼50 nm blueshift in the reflection peak position per percent increase in strain. These results suggest that architected nanolattices can serve as efficient three-dimensional mechanically tunable photonic crystals, providing a foundation for new opto-mechanical components and devices across infrared and possibly visible frequencies.

  16. Non-Gaussian Photon Probability Distribution

    SciTech Connect (OSTI)

    Solomon, Benjamin T.

    2010-01-28

    This paper investigates the axiom that the photon's probability distribution is a Gaussian distribution. The Airy disc empirical evidence shows that the best fit, if not exact, distribution is a modified Gamma mGAMMA distribution (whose parameters are alpha = r, betar/sq root(u)) in the plane orthogonal to the motion of the photon. This modified Gamma distribution is then used to reconstruct the probability distributions along the hypotenuse from the pinhole, arc from the pinhole, and a line parallel to photon motion. This reconstruction shows that the photon's probability distribution is not a Gaussian function. However, under certain conditions, the distribution can appear to be Normal, thereby accounting for the success of quantum mechanics. This modified Gamma distribution changes with the shape of objects around it and thus explains how the observer alters the observation. This property therefore places additional constraints to quantum entanglement experiments. This paper shows that photon interaction is a multi-phenomena effect consisting of the probability to interact P{sub i}, the probabilistic function and the ability to interact A{sub i}, the electromagnetic function. Splitting the probability function P{sub i} from the electromagnetic function A{sub i} enables the investigation of the photon behavior from a purely probabilistic P{sub i} perspective. The Probabilistic Interaction Hypothesis is proposed as a consistent method for handling the two different phenomena, the probability function P{sub i} and the ability to interact A{sub i}, thus redefining radiation shielding, stealth or cloaking, and invisibility as different effects of a single phenomenon P{sub i} of the photon probability distribution. Sub wavelength photon behavior is successfully modeled as a multi-phenomena behavior. The Probabilistic Interaction Hypothesis provides a good fit to Otoshi's (1972) microwave shielding, Schurig et al.(2006) microwave cloaking, and Oulton et al.(2008) sub

  17. Measurement of the inclusive isolated prompt photon production cross section at the Tevatron using the CDF detector

    SciTech Connect (OSTI)

    Deluca Silberberg, Carolina; /Barcelona, IFAE

    2009-04-01

    In this thesis we present the measurement of the inclusive isolated prompt photon cross section with a total integrated luminosity of 2.5 fb{sup -1} of data collected with the CDF Run II detector at the Fermilab Tevatron Collider. The prompt photon cross section is a classic measurement to test perturbative QCD (pQCD) with potential to provide information on the parton distribution function (PDF), and sensitive to the presence of new physics at large photon transverse momentum. Prompt photons also constitute an irreducible background for important searches such as H {yields} {gamma}{gamma}, or SUSY and extra-dimensions with energetic photons in the final state. The Tevatron at Fermilab (Batavia, U.S.A.) is currently the hadron collider that operates at the highest energies in the world. It collides protons and antiprotons with a center-of-mass energy of 1.96 TeV. The CDF and the D0 experiments are located in two of its four interaction regions. In Run I at the Tevatron, the direct photon production cross section was measured by both CDF and DO, and first results in Run II have been presented by the DO Collaboration based on 380 pb{sup -1}. Both Run I and Run II results show agreement with the theoretical predictions except for the low p{sub T}{sup {gamma}} region, where the observed and predicted shapes are different. Prompt photon production has been also extensively measured at fixed-target experiments in lower p{sub T}{sup {gamma}} ranges, showing excess of data compared to the theory, particularly at high x{sub T}. From an experimental point of view, the study of the direct photon production has several advantages compared to QCD studies using jets. Electromagnetic calorimeters have better energy resolution than hadronic calorimeters, and the systematic uncertainty on the photon absolute energy scale is smaller. Furthermore, the determination of the photon kinematics does not require the use of jet algorithms. However, the measurements using photons require a

  18. Optical waveguide device with an adiabatically-varying width

    DOE Patents [OSTI]

    Watts; Michael R. , Nielson; Gregory N.

    2011-05-10

    Optical waveguide devices are disclosed which utilize an optical waveguide having a waveguide bend therein with a width that varies adiabatically between a minimum value and a maximum value of the width. One or more connecting members can be attached to the waveguide bend near the maximum value of the width thereof to support the waveguide bend or to supply electrical power to an impurity-doped region located within the waveguide bend near the maximum value of the width. The impurity-doped region can form an electrical heater or a semiconductor junction which can be activated with a voltage to provide a variable optical path length in the optical waveguide. The optical waveguide devices can be used to form a tunable interferometer (e.g. a Mach-Zehnder interferometer) which can be used for optical modulation or switching. The optical waveguide devices can also be used to form an optical delay line.

  19. Optical manifold

    DOE Patents [OSTI]

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

    2010-02-23

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

  20. Epi-detected quadruple-modal nonlinear optical microscopy for label-free imaging of the tooth

    SciTech Connect (OSTI)

    Wang, Zi; Zheng, Wei; Huang, Zhiwei; Stephen Hsu, Chin-Ying

    2015-01-19

    We present an epi-detected quadruple-modal nonlinear optical microscopic imaging technique (i.e., coherent anti-Stokes Raman scattering (CARS), second-harmonic generation (SHG), third-harmonic generation (THG), and two-photon excited fluorescence (TPEF)) based on a picosecond (ps) laser-pumped optical parametric oscillator system for label-free imaging of the tooth. We demonstrate that high contrast ps-CARS images covering both the fingerprint (500–1800 cm{sup −1}) and high-wavenumber (2500–3800 cm{sup −1}) regions can be acquired to uncover the distributions of mineral and organic biomaterials in the tooth, while high quality TPEF, SHG, and THG images of the tooth can also be acquired under ps laser excitation without damaging the samples. The quadruple-modal nonlinear microscopic images (CARS/SHG/THG/TPEF) acquired provide better understanding of morphological structures and biochemical/biomolecular distributions in the dentin, enamel, and the dentin-enamel junction of the tooth without labeling, facilitating optical diagnosis and characterization of the tooth in dentistry.

  1. Optical reflection and contactless electroreflection from GaAlAs layers with periodically arranged GaAs quantum wells

    SciTech Connect (OSTI)

    Chaldyshev, V. V. Shkol'nik, A. S.; Evtikhiev, V. P.; Holden, T.

    2006-12-15

    Optical reflection and electroreflection for the AlGaAs layers containing the periodically arranged GaAs quantum wells of different thickness are studied at photon energies ranging from 1 to 2 eV. It is established that the spectral dependence of the reflectance involves three different contributions made by (i) the reflection from the medium-air interface; (ii) the interference reflection due to the periodically modulated refractive index, since the materials of the wells and barriers have different refractive indices; and (iii) the reflection produced by the interaction of electromagnetic waves with the excition states in the quantum wells. Analysis of the reflection spectra shows that these contributions are characterized by different behavior with variations in temperature, angle of incidence of light, and polarization; however, quantitative separation of the spectra into individual contributions presents a rather difficult problem. To separate the contribution originating from the interaction of light with the exciton states from the optical spectra, a special approach based on contactless measurements of the optical electroreflectance over a certain spectral region is developed. It is shown that this method provides a means for determining the parameters of the exciton states in the quantum wells.

  2. Dark photons as fractional cosmic neutrino masquerader

    SciTech Connect (OSTI)

    Ng, Kin-Wang; Tu, Huitzu; Yuan, Tzu-Chiang E-mail: huitzu@phys.sinica.edu.tw

    2014-09-01

    Recently, Weinberg proposed a Higgs portal model with a spontaneously broken global U(1) symmetry in which Goldstone bosons may be masquerading as fractional cosmic neutrinos. We extend the model by gauging the U(1) symmetry. This gives rise to the so-called dark photon and dark Higgs. The dark photons can constitute about 0.912 (0.167) to the effective number of light neutrino species if they decouple from the thermal bath before the pions become non-relativistic and after (before) the QCD transition. Restriction on the parameter space of the portal coupling and the dark Higgs mass is obtained from the freeze-out condition of the dark photons. Combining with the collider data constraints on the invisible width of the standard model Higgs requires the dark Higgs mass to be less than a few GeV.

  3. Regional Information

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

    Regional Information There is plenty to do and see in the cities of Golden and Denver, Colorado. Here you'll find links to general information about these areas, plus hospitals, local universities and colleges, entertainment, sports, amusement parks, and more. Golden City of Golden Golden's 2-Hour Vacation Denver www.denver.com www.denver.org Denver Public Library Colorado State of Colorado Colorado tourism Transportation (Bus and Light Rail) RTD Hospitals Largest Hospitals in Metro Denver

  4. Strong transmittance above the light line in mid-infrared two-dimensional photonic crystals

    SciTech Connect (OSTI)

    Kraeh, Christian; Martinez-Hurtado, J. L.; Zeitlmair, Martin; Finley, Jonathan J.; Popescu, Alexandru; Hedler, Harry

    2015-06-14

    The mid-infrared region of the electromagnetic spectrum between 3 and 8 μm hosts absorption lines of gases relevant for chemical and biological sensing. 2D photonic crystal structures capable of guiding light in this region of the spectrum have been widely studied, and their implementation into miniaturized sensors has been proposed. However, light guiding in conventional 2D photonic crystals is usually restricted to a frequency range below the light line, which is the dispersion relation of light in the media surrounding the structures. These structures rely on total internal reflection for confinement of the light in z-direction normal to the lattice plane. In this work, 2D mid-infrared photonic crystals consisting of microtube arrays that mitigate these limitations have been developed. Due to their high aspect ratios of ∼1:30, they are perceived as semi-infinite in the z-direction. Light transmission experiments in the 5–8 μm range reveal attenuations as low as 0.27 dB/100 μm, surpassing the limitations for light guiding above the light line in conventional 2D photonic crystals. Fair agreement is obtained between these experiments, 2D band structure and transmission simulations.

  5. Laser isotope separation by multiple photon absorption

    DOE Patents [OSTI]

    Robinson, C. Paul; Rockwood, Stephen D.; Jensen, Reed J.; Lyman, John L.; Aldridge, III, Jack P.

    1987-01-01

    Multiple photon absorption from an intense beam of infrared laser light may be used to induce selective chemical reactions in molecular species which result in isotope separation or enrichment. The molecular species must have a sufficient density of vibrational states in its vibrational manifold that, is the presence of sufficiently intense infrared laser light tuned to selectively excite only those molecules containing a particular isotope, multiple photon absorption can occur. By this technique, for example, intense CO.sub.2 laser light may be used to highly enrich .sup.34 S in natural SF.sub.6 and .sup.11 B in natural BCl.sub.3.

  6. Laser isotope separation by multiple photon absorption

    DOE Patents [OSTI]

    Robinson, C. Paul; Rockwood, Stephen D.; Jensen, Reed J.; Lyman, John L.; Aldridge, III, Jack P.

    1977-01-01

    Multiple photon absorption from an intense beam of infrared laser light may be used to induce selective chemical reactions in molecular species which result in isotope separation or enrichment. The molecular species must have a sufficient density of vibrational states in its vibrational manifold that, in the presence of sufficiently intense infrared laser light tuned to selectively excite only those molecules containing a particular isotope, multiple photon absorption can occur. By this technique, for example, intense CO.sub.2 laser light may be used to highly enrich .sup.34 S in natural SF.sub.6 and .sup.11 B in natural BCl.sub.3.

  7. Laser isotope separation by multiple photon absorption

    DOE Patents [OSTI]

    Robinson, C.P.; Rockwood, S.D.; Jensen, R.J.; Lyman, J.L.; Aldridge, J.P. III.

    1987-04-07

    Multiple photon absorption from an intense beam of infrared laser light may be used to induce selective chemical reactions in molecular species which result in isotope separation or enrichment. The molecular species must have a sufficient density of vibrational states in its vibrational manifold that, is the presence of sufficiently intense infrared laser light tuned to selectively excite only those molecules containing a particular isotope, multiple photon absorption can occur. By this technique, for example, intense CO[sub 2] laser light may be used to highly enrich [sup 34]S in natural SF[sub 6] and [sup 11]B in natural BCl[sub 3]. 8 figs.

  8. Nickel porphyrins for memory optical applications

    DOE Patents [OSTI]

    Shelnutt, John A.; Jia, Songling; Medforth, Craig; Holten, Dewey; Nelson, Nora Y.; Smith, Kevin M.

    2000-01-01

    The present invention relates to a nickel-porphyrin derivative in a matrix, the nickel-porphyrin derivative comprising at least two conformational isomers, a lower-energy-state conformer and a higher-energy-state conformer, such that when the higher-energy-state conformer is generated from the lower-energy-state conformer following absorption of a photon of suitable energy, the time to return to the lower-energy-state conformer is greater than 40 nanoseconds at approximately room temperature. The nickel-porphyrin derivative is useful in optical memory applications.

  9. Quantum optics. Gravity meets quantum physics

    SciTech Connect (OSTI)

    Adams, Bernhard W.

    2015-02-27

    Albert Einstein’s general theory of relativity is a classical formulation but a quantum mechanical description of gravitational forces is needed, not only to investigate the coupling of classical and quantum systems but simply to give a more complete description of our physical surroundings. In this issue of Nature Photonics, Wen-Te Liao and Sven Ahrens reveal a link between quantum and gravitational physics. They propose that in the quantum-optical effect of superradiance, the world line of electromagnetic radiation is changed by the presence of a gravitational field.

  10. Temporal waveguides for optical pulses

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

    Plansinis, Brent W.; Donaldson, William R.; Agrawal, Govind P.

    2016-05-12

    Here we discuss, temporal total internal reflection (TIR), in analogy to the conventional TIR of an optical beam at a dielectric interface, is the total reflection of an optical pulse inside a dispersive medium at a temporal boundary across which the refractive index changes. A pair of such boundaries separated in time acts as the temporal analog of planar dielectric waveguides. We study the propagation of optical pulses inside such temporal waveguides, both analytically and numerically, and show that the waveguide supports a finite number of temporal modes. We also discuss how a single-mode temporal waveguide can be created inmore » practice. In contrast with the spatial case, the confinement can occur even when the central region has a lower refractive index.« less

  11. Photonic crystal light emitting diode based on Er and Si nanoclusters co-doped slot waveguide

    SciTech Connect (OSTI)

    Lo Savio, R.; Galli, M.; Liscidini, M.; Andreani, L. C.; Franz, G.; Iacona, F.; Miritello, M.; Irrera, A.; Sanfilippo, D.; Piana, A.; Priolo, F.

    2014-03-24

    We report on the design, fabrication, and electro-optical characterization of a light emitting device operating at 1.54??m, whose active layer consists of silicon oxide containing Er-doped Si nanoclusters. A photonic crystal (PhC) is fabricated on the top-electrode to enhance the light extraction in the vertical direction, and thus the external efficiency of the device. This occurs if a photonic mode of the PhC slab is resonant with the Er emission energy, as confirmed by theoretical calculations and experimental analyses. We measure an increase of the extraction efficiency by a factor of 3 with a high directionality of light emission in a narrow vertical cone. External quantum efficiency and power efficiency are among the highest reported for this kind of material. These results are important for the realization of CMOS-compatible efficient light emitters at telecom wavelengths.

  12. Photon-noise limited sensitivity in titanium nitride kinetic inductance detectors

    SciTech Connect (OSTI)

    Hubmayr, J. Beall, J.; Becker, D.; Cho, H.-M.; Hilton, G. C.; Li, D.; Pappas, D. P.; Van Lanen, J.; Vissers, M. R.; Gao, J.; Devlin, M.; Dober, B.; Groppi, C.; Mauskopf, P.; Irwin, K. D.; Wang, Y.; Wei, L. F.

    2015-02-16

    We demonstrate photon-noise limited performance at sub-millimeter wavelengths in feedhorn-coupled, microwave kinetic inductance detectors made of a TiN/Ti/TiN trilayer superconducting film, tuned to have a transition temperature of 1.4 K. Micro-machining of the silicon-on-insulator wafer backside creates a quarter-wavelength backshort optimized for efficient coupling at 250 μm. Using frequency read out and when viewing a variable temperature blackbody source, we measure device noise consistent with photon noise when the incident optical power is >0.5 pW, corresponding to noise equivalent powers >3×10{sup −17} W/√(Hz). This sensitivity makes these devices suitable for broadband photometric applications at these wavelengths.

  13. Spatial correlation of photon pairs produced in spontaneous parametric down-conversion

    SciTech Connect (OSTI)

    Procopio, L. M. [Departamento de Fisica, Cinvestav, A.P. 14-740, Mexico D.F. 07000 (Mexico); Rosas-Ortiz, O. [Departamento de Fisica, Cinvestav, A.P. 14-740, Mexico D.F. 07000 (Mexico); Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, Mexico D.F. 01000 (Mexico); Velazquez, V. [Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, A.P. 20-364, Mexico D.F. 04510 (Mexico)

    2010-10-11

    We report the observation of spatial biphoton correlation in spontaneous parametric down conversion. The optical bench includes a type-I BBO crystal of effective length 2 mm, pumped by a 100 mW violet laser diode centered at 405.38 nm. Photon pairs are created with degenerate wavelength {approx_equal}810.76 nm. Once the horizontal counting rates have been measured, a simple geometrical recipe is shown to be useful in calculating bounds for the width of vertical counting rates. The spatial correlation between idler and signal photons is illustrated with a coincidence distribution of the coordinate pair (x{sub s},x{sub i}), with x{sub i,s} the idler (signal) detector position in horizontal scan.

  14. The Commissioning Results of the First Beamline at the Siam Photon Laboratory

    SciTech Connect (OSTI)

    Songsiriritthigul, Prayoon; Pairsuwan, W.; Ishii, T.; Nakajima, H.; Kantee, S.; Wongkokua, W.; Kakizaki, A.

    2004-05-12

    The commissioning results obtained from the first beamline of the Siam Photon Source are reported. The beamline is a VUV beamline in which light is monochromatized over the energy range between 20-240 eV. The wavelength calibration was carried out by photoemission measurements using the Fermi edge of gold as the standard. The optical beamline and the experimental station have been tested while the Siam Photon Source was still in the commissioning period. This gave rise to undesirable problems: the large electron beam size, the beam instability and the following intensity fluctuation. Such problem has been overcome up to the present. The photoemission measurements are being carried out on Ni(111)

  15. Optical data latch

    DOE Patents [OSTI]

    Vawter, G. Allen

    2010-08-31

    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.

  16. Efficient modeling of photonic crystals with local Hermite polynomials

    SciTech Connect (OSTI)

    Boucher, C. R.; Li, Zehao; Albrecht, J. D.; Ram-Mohan, L. R.

    2014-04-21

    Developing compact algorithms for accurate electrodynamic calculations with minimal computational cost is an active area of research given the increasing complexity in the design of electromagnetic composite structures such as photonic crystals, metamaterials, optical interconnects, and on-chip routing. We show that electric and magnetic (EM) fields can be calculated using scalar Hermite interpolation polynomials as the numerical basis functions without having to invoke edge-based vector finite elements to suppress spurious solutions or to satisfy boundary conditions. This approach offers several fundamental advantages as evidenced through band structure solutions for periodic systems and through waveguide analysis. Compared with reciprocal space (plane wave expansion) methods for periodic systems, advantages are shown in computational costs, the ability to capture spatial complexity in the dielectric distributions, the demonstration of numerical convergence with scaling, and variational eigenfunctions free of numerical artifacts that arise from mixed-order real space basis sets or the inherent aberrations from transforming reciprocal space solutions of finite expansions. The photonic band structure of a simple crystal is used as a benchmark comparison and the ability to capture the effects of spatially complex dielectric distributions is treated using a complex pattern with highly irregular features that would stress spatial transform limits. This general method is applicable to a broad class of physical systems, e.g., to semiconducting lasers which require simultaneous modeling of transitions in quantum wells or dots together with EM cavity calculations, to modeling plasmonic structures in the presence of EM field emissions, and to on-chip propagation within monolithic integrated circuits.

  17. Optical absorption measurement system

    DOE Patents [OSTI]

    Draggoo, Vaughn G.; Morton, Richard G.; Sawicki, Richard H.; Bissinger, Horst D.

    1989-01-01

    The system of the present invention contemplates a non-intrusive method for measuring the temperature rise of optical elements under high laser power optical loading to determine the absorption coefficient. The method comprises irradiating the optical element with a high average power laser beam, viewing the optical element with an infrared camera to determine the temperature across the optical element and calculating the absorption of the optical element from the temperature.

  18. Harnessing Light: Capitalizing on Optical Science Trends and Challenges for Future Research. Final Technical Report

    SciTech Connect (OSTI)

    Svedberg, Erik

    2014-02-06

    The committee has during the earlier period finalized their work on the report, Optics and Photonics: Essential Technologies for Our Nation (2013) . The report did undergo review and initial editorial processing. The NRC released a pre-publication report on August 13, 2012. A final report is now available. The study director has been able to practice his skills in running a national academies committee. From a research perspective the grant has generated a report with recommendations to the government. The work itself is the meetings where the committee convened to hear presenters and to discuss the status of optics and photonics as well as writing the report.

  19. Advanced Optical Technologies

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

    The Advanced Optical Components and Technologies program develops, creates and provides critical optical components for laser-based missions at LLNL. Past projects focused on ...

  20. Optical extensometer

    DOE Patents [OSTI]

    Walker, Ray A.; Reich, Fred R.; Russell, James T.

    1978-01-01

    An optical extensometer is described using sequentially pulsed light beams for measuring the dimensions of objects by detecting two opposite edges of the object without contacting the object. The light beams may be of different distinguishable light characteristics, such as polarization or wave length, and are time modulated in an alternating manner at a reference frequency. The light characteristics are of substantially the same total light energy and are distributed symmetrically. In the preferred embodiment two light beam segments of one characteristic are on opposite sides of a middle segment of another characteristic. As a result, when the beam segments are scanned sequentially across two opposite edges of the object, they produce a readout signal at the output of a photoelectric detector that is compared with the reference signal by a phase comparator to produce a measurement signal with a binary level transition when the light beams cross an edge. The light beams may be of different cross sectional geometries, including two superimposed and concentric circular beam cross sections of different diameter, or two rectangular cross sections which intersect with each other substantially perpendicular so only their central portions are superimposed. Alternately, a row of three light beams can be used including two outer beams on opposite sides and separate from a middle beam. The three beams may all be of the same light characteristic. However it is preferable that the middle beam be of a different characteristic but of the same total energy as the two outer beams.

  1. Two-photon fluorescence microscopy signal formation in highly scattering media: theoretical and numerical simulation

    SciTech Connect (OSTI)

    Sergeeva, Ekaterina A; Katichev, A R; Kirillin, M Yu

    2011-01-24

    Using the radiative transfer theory and Monte Carlo simulations, we analyse the effect of scattering in a medium and of the size of the detector pinhole on the formation of the fluorescent signal in standard two-photon fluorescence microscopy (TPFM) systems. The theoretical analysis is based on a small-angle diffusion approximation of the radiative transfer equation, adapted to calculate the propagation of focused infrared radiation in media similar to the biological tissues in their optical properties. The accuracy of the model is evaluated by comparing the calculated excitation intensity in a highly scattering medium with the results of Monte Carlo simulations. To simulate a tightly focused Gaussian beam by the Monte Carlo method, the so called 'ray-optics' approach that correctly takes into account the finite size and shape of the beam waist is applied. It is shown that in the combined confocal and two-photon scanning microscopy systems not equipped with an external 'nondescanned' detector, the scattering significantly affects both the nonlinear excitation efficiency in the medium and the fluorescence collection efficiency of the system. In such systems, the rate of the useful TPFM signal in-depth decay is 1.5 - 2 times higher than in systems equipped with a 'nondescanned' detector. (application of lasers and laser-optical methods in life sciences)

  2. GE leads the way in photonics research | GE Global Research

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

    GE continues leading role in photonics industry - from LED to digital x-ray Click to email ... GE continues leading role in photonics industry - from LED to digital x-ray Danielle ...

  3. Angle sensitive single photon avalanche diode

    SciTech Connect (OSTI)

    Lee, Changhyuk Johnson, Ben Molnar, Alyosha

    2015-06-08

    An ideal light sensor would provide exact information on intensity, timing, location, and angle of incoming photons. Single photon avalanche diodes (SPADs) provide such desired high (single photon) sensitivity with precise time information and can be implemented at a pixel-scale to form an array to extract spatial information. Furthermore, recent work has demonstrated photodiode-based structures (combined with micro-lenses or diffraction gratings) that are capable of encoding both spatial and angular information of incident light. In this letter, we describe the implementation of such a grating structure on SPADs to realize a pixel-scale angle-sensitive single photon avalanche diode (A-SPAD) built in a standard CMOS process. While the underlying SPAD structure provides high sensitivity, the time information of the two layers of diffraction gratings above offers angle-sensitivity. Such a unique combination of SPAD and diffraction gratings expands the sensing dimensions to pave a path towards lens-less 3-D imaging and light-field time-of-flight imaging.

  4. Meson-photon transition form factors

    SciTech Connect (OSTI)

    Balakireva, Irina; Lucha, Wolfgang; Melikhov, Dmitri

    2012-10-23

    We present the results of our recent analysis of the meson-photon transition form factors F{sub P{gamma}}(Q{sup 2}) for the pseudoscalar mesons P {pi}{sup 0},{eta},{eta} Prime ,{eta}{sub c}, using the local-duality version of QCD sum rules.

  5. Photon structure function at small x

    SciTech Connect (OSTI)

    Gluck, M.; Reya, E.; Schienbein, I.

    2001-07-01

    It is shown that recent small-x measurements of the photon structure function F{sub 2}{sup {gamma}}(x,Q{sup 2}) by the CERN LEP OPAL Collaboration are consistent with parameter-free QCD predictions at all presently accessible values of Q{sup 2}.

  6. Isolated prompt photon production at CDF

    SciTech Connect (OSTI)

    Maas, P.A. )

    1992-11-01

    This note describes measurements of isolated prompt photon production at [radical]s = 1.8 TeV using the CDF experiment. The measurements are compared to recent NLO QCD calculations, including recently obtained parton distribution functions. Qualitatively, the QCD calculation with the new parton distribution functions agrees better with the data than the previous parton distribution functions.

  7. Optical coherence domain reflectometry guidewire

    DOE Patents [OSTI]

    Colston, Billy W.; Everett, Matthew; Da Silva, Luiz B.; Matthews, Dennis

    2001-01-01

    A guidewire with optical sensing capabilities is based on a multiplexed optical coherence domain reflectometer (OCDR), which allows it to sense location, thickness, and structure of the arterial walls or other intra-cavity regions as it travels through the body during minimally invasive medical procedures. This information will be used both to direct the guidewire through the body by detecting vascular junctions and to evaluate the nearby tissue. The guidewire contains multiple optical fibers which couple light from the proximal to distal end. Light from the fibers at the distal end of the guidewire is directed onto interior cavity walls via small diameter optics such as gradient index lenses and mirrored corner cubes. Both forward viewing and side viewing fibers can be included. The light reflected or scattered from the cavity walls is then collected by the fibers, which are multiplexed at the proximal end to the sample arm of an optical low coherence reflectometer. The guidewire can also be used in nonmedical applications.

  8. Optical NAND gate

    DOE Patents [OSTI]

    Skogen, Erik J.; Raring, James; Tauke-Pedretti, Anna

    2011-08-09

    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.

  9. Ultrafast electrical control of a resonantly driven single photon source

    SciTech Connect (OSTI)

    Cao, Y.; Bennett, A. J. Ellis, D. J. P.; Shields, A. J.; Farrer, I.; Ritchie, D. A.

    2014-08-04

    We demonstrate generation of a pulsed stream of electrically triggered single photons in resonance fluorescence, by applying high frequency electrical pulses to a single quantum dot in a p-i-n diode under resonant laser excitation. Single photon emission was verified, with the probability of multiple photon emission reduced to 2.8%. We show that despite the presence of charge noise in the emission spectrum of the dot, resonant excitation acts as a filter to generate narrow bandwidth photons.

  10. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    Symmetry Breaking of H2 Dissociation by a Single Photon Symmetry Breaking of H2 Dissociation by a Single Photon Print Wednesday, 25 July 2007 00:00 A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen

  11. Vacuum birefringence in strong magnetic fields: (I) Photon polarization tensor with all the Landau levels

    SciTech Connect (OSTI)

    Hattori, Koichi; Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 ; Itakura, Kazunori; Department of Particle and Nuclear Studies, Graduate University for Advanced Studies , 1-1 Oho, Tsukuba, Ibaraki 305-0801

    2013-03-15

    Photons propagating in strong magnetic fields are subject to a phenomenon called the 'vacuum birefringence' where refractive indices of two physical modes both deviate from unity and are different from each other. We compute the vacuum polarization tensor of a photon in a static and homogeneous magnetic field by utilizing Schwinger's proper-time method, and obtain a series representation as a result of double integrals analytically performed with respect to proper-time variables. The outcome is expressed in terms of an infinite sum of known functions which is plausibly interpreted as summation over all the Landau levels of fermions. Each contribution from infinitely many Landau levels yields a kinematical condition above which the contribution has an imaginary part. This indicates decay of a sufficiently energetic photon into a fermion-antifermion pair with corresponding Landau level indices. Since we do not resort to any approximation, our result is applicable to the calculation of refractive indices in the whole kinematical region of a photon momentum and in any magnitude of the external magnetic field. - Highlights: Black-Right-Pointing-Pointer Vacuum birefringence is studied in the presence of externally applied magnetic field. Black-Right-Pointing-Pointer A general framework is given on the basis of a vacuum polarization tensor of photon. Black-Right-Pointing-Pointer A resummed vacuum polarization tensor is calculated analytically and exactly. Black-Right-Pointing-Pointer Contributions of all the Landau levels are obtained in the form of an infinite sum. Black-Right-Pointing-Pointer Threshold behavior of real-photon decay is obtained at the each Landau level.

  12. Simulating three-dimensional nonthermal high-energy photon emission in colliding-wind binaries

    SciTech Connect (OSTI)

    Reitberger, K.; Kissmann, R.; Reimer, A.; Reimer, O.

    2014-07-01

    Massive stars in binary systems have long been regarded as potential sources of high-energy γ rays. The emission is principally thought to arise in the region where the stellar winds collide and accelerate relativistic particles which subsequently emit γ rays. On the basis of a three-dimensional distribution function of high-energy particles in the wind collision region—as obtained by a numerical hydrodynamics and particle transport model—we present the computation of the three-dimensional nonthermal photon emission for a given line of sight. Anisotropic inverse Compton emission is modeled using the target radiation field of both stars. Photons from relativistic bremsstrahlung and neutral pion decay are computed on the basis of local wind plasma densities. We also consider photon-photon opacity effects due to the dense radiation fields of the stars. Results are shown for different stellar separations of a given binary system comprising of a B star and a Wolf-Rayet star. The influence of orbital orientation with respect to the line of sight is also studied by using different orbital viewing angles. For the chosen electron-proton injection ratio of 10{sup –2}, we present the ensuing photon emission in terms of two-dimensional projections maps, spectral energy distributions, and integrated photon flux values in various energy bands. Here, we find a transition from hadron-dominated to lepton-dominated high-energy emission with increasing stellar separations. In addition, we confirm findings from previous analytic modeling that the spectral energy distribution varies significantly with orbital orientation.

  13. Fluorescent optical position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2005-11-15

    A fluorescent optical position sensor and method of operation. A small excitation source side-pumps a localized region of fluorescence at an unknown position along a fluorescent waveguide. As the fluorescent light travels down the waveguide, the intensity of fluorescent light decreases due to absorption. By measuring with one (or two) photodetectors the attenuated intensity of fluorescent light emitted from one (or both) ends of the waveguide, the position of the excitation source relative to the waveguide can be determined by comparing the measured light intensity to a calibrated response curve or mathematical model. Alternatively, excitation light can be pumped into an end of the waveguide, which generates an exponentially-decaying continuous source of fluorescent light along the length of the waveguide. The position of a photodetector oriented to view the side of the waveguide can be uniquely determined by measuring the intensity of the fluorescent light emitted radially at that location.

  14. Conferences and Workshops | Advanced Photon Source

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

    Laboratory, Argonne, IL May 17-21 Conference on Advanced Phase Measurement Methods in Optics and Imaging, with Special Sessions for X-ray Methods Monte Verita, Locarno,...

  15. Disorder-induced transparency in a one-dimensional waveguide side coupled with optical cavities

    SciTech Connect (OSTI)

    Zhang, Yongyou Dong, Guangda; Zou, Bingsuo

    2014-05-07

    Disorder influence on photon transmission behavior is theoretically studied in a one-dimensional waveguide side coupled with a series of optical cavities. For this sake, we propose a concept of disorder-induced transparency appearing on the low-transmission spectral background. Two kinds of disorders, namely, disorders of optical cavity eigenfrequencies and relative phases in the waveguide side coupled with optical cavities are considered to show the disorder-induced transparency. They both can induce the optical transmission peaks on the low-transmission backgrounds. The statistical mean value of the transmission also increases with increasing the disorders of the cavity eigenfrequencies and relative phases.

  16. High quantum efficiency and low dark count rate in multi-layer superconducting nanowire single-photon detectors

    SciTech Connect (OSTI)

    Jafari Salim, A. Eftekharian, A.; Hamed Majedi, A.

    2014-02-07

    In this paper, we theoretically show that a multi-layer superconducting nanowire single-photon detector (SNSPD) is capable of approaching characteristics of an ideal SNSPD in terms of the quantum efficiency, dark count, and band-width. A multi-layer structure improves the performance in two ways. First, the potential barrier for thermally activated vortex crossing, which is the major source of dark counts and the reduction of the critical current in SNSPDs is elevated. In a multi-layer SNSPD, a vortex is made of 2D-pancake vortices that form a stack. It will be shown that the stack of pancake vortices effectively experiences a larger potential barrier compared to a vortex in a single-layer SNSPD. This leads to an increase in the experimental critical current as well as significant decrease in the dark count rate. In consequence, an increase in the quantum efficiency for photons of the same energy or an increase in the sensitivity to photons of lower energy is achieved. Second, a multi-layer structure improves the efficiency of single-photon absorption by increasing the effective optical thickness without compromising the single-photon sensitivity.

  17. Efficient detection of photons emitted from fast moving atoms

    SciTech Connect (OSTI)

    Lehmann, Bernhard; Quintel, Harald; Ludin, Andrea; Tschannen, Thomas

    1997-01-15

    Metastable atoms of krypton and photons from a tunable cw infrared diode laser at 812 nm meet in counterpropagating beams. A photomultiplier mounted perpendicular to the beams detects photons reemitted from the passing atoms. Multiple diffuse reflections from a thermoplastics tube are used to achieve the high collection efficiency necessary for photon burst detection.

  18. Manipulation of fluids in three-dimensional porous photonic structures with patterned surface properties

    DOE Patents [OSTI]

    Aizenberg, Joanna; Burgess, Ian B.; Mishchenko, Lidiya; Hatton, Benjamin; Loncar, Marko

    2016-03-08

    A three-dimensional porous photonic structure, whose internal pore surfaces can be provided with desired surface properties in a spatially selective manner with arbitrary patterns, and methods for making the same are described. When exposed to a fluid (e.g., via immersion or wicking), the fluid can selectively penetrate the regions of the structure with compatible surface properties. Broad applications, for example in security, encryption and document authentication, as well as in areas such as simple microfluidics and diagnostics, are anticipated.

  19. An ultrafast electron microscope gun driven by two-photon photoemission from a nanotip cathode

    SciTech Connect (OSTI)

    Bormann, Reiner; Strauch, Stefanie; Schäfer, Sascha Ropers, Claus

    2015-11-07

    We experimentally and numerically investigate the performance of an advanced ultrafast electron source, based on two-photon photoemission from a tungsten needle cathode incorporated in an electron microscope gun geometry. Emission properties are characterized as a function of the electrostatic gun settings, and operating conditions leading to laser-triggered electron beams of very low emittance (below 20 nm mrad) are identified. The results highlight the excellent suitability of optically driven nano-cathodes for the further development of ultrafast transmission electron microscopy.

  20. Microcavity Polaritonics: Optically-Steering Interacting Quantum Liquids on

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

    a Chip | MIT-Harvard Center for Excitonics Microcavity Polaritonics: Optically-Steering Interacting Quantum Liquids on a Chip October 17, 2013 at 3pm/36-428 Jeremy Baumberg Department of Physics NanoPhotonics Centre, University of Cambridge, UK baumberg002_001 Abstract: Constructing ultra-high finesse semiconductor microcavities produces quasiparticles called exciton polaritons which can Bose condense even up to room temperature. The resulting macroscopic quantum states are directly visible

  1. Quantum-dot based nanothermometry in optical plasmonic recording media

    SciTech Connect (OSTI)

    Maestro, Laura Martinez; Zhang, Qiming; Li, Xiangping; Gu, Min; Jaque, Daniel

    2014-11-03

    We report on the direct experimental determination of the temperature increment caused by laser irradiation in a optical recording media constituted by a polymeric film in which gold nanorods have been incorporated. The incorporation of CdSe quantum dots in the recording media allowed for single beam thermal reading of the on-focus temperature from a simple analysis of the two-photon excited fluorescence of quantum dots. Experimental results have been compared with numerical simulations revealing an excellent agreement and opening a promising avenue for further understanding and optimization of optical writing processes and media.

  2. Fiber optic connector

    DOE Patents [OSTI]

    Rajic, S.; Muhs, J.D.

    1996-10-22

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded are disclosed. 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. 3 figs.

  3. Optical NOR gate

    DOE Patents [OSTI]

    Skogen, Erik J.; Tauke-Pedretti, Anna

    2011-09-06

    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.

  4. Optical limiting effects in nanostructured silicon carbide thin films

    SciTech Connect (OSTI)

    Borshch, A A; Starkov, V N; Volkov, V I; Rudenko, V I; Boyarchuk, A Yu; Semenov, A V

    2013-12-31

    We present the results of experiments on the interaction of nanosecond laser radiation at 532 and 1064 nm with nanostructured silicon carbide thin films of different polytypes. We have found the effect of optical intensity limiting at both wavelengths. The intensity of optical limiting at ? = 532 nm (I{sub cl} ? 10{sup 6} W cm{sup -2}) is shown to be an order of magnitude less than that at ? = 1064 nm (I{sub cl} ? 10{sup 7} W cm{sup -2}). We discuss the nature of the nonlinearity, leading to the optical limiting effect. We have proposed a method for determining the amount of linear and two-photon absorption in material media. (nonlinear optical phenomena)

  5. Method for photon activation positron annihilation analysis

    DOE Patents [OSTI]

    Akers, Douglas W.

    2006-06-06

    A non-destructive testing method comprises providing a specimen having at least one positron emitter therein; determining a threshold energy for activating the positron emitter; and determining whether a half-life of the positron emitter is less than a selected half-life. If the half-life of the positron emitter is greater than or equal to the selected half-life, then activating the positron emitter by bombarding the specimen with photons having energies greater than the threshold energy and detecting gamma rays produced by annihilation of positrons in the specimen. If the half-life of the positron emitter is less then the selected half-life, then alternately activating the positron emitter by bombarding the specimen with photons having energies greater then the threshold energy and detecting gamma rays produced by positron annihilation within the specimen.

  6. Dynamics of optical pulses in waveguides with a large self-steepening parameter

    SciTech Connect (OSTI)

    Zhuravlev, V M; Zolotovskii, I O; Korobko, D A; Fotiadi, A A

    2013-11-30

    We study the dynamics of a high-energy laser pulse in dispersive optical media with large values of self-steepening. We consider the formation of soliton-like peaks at the front of the envelope in such media with anomalous dispersion. We show the possibility of realisation of a medium based on a photonic crystal waveguide with a very large absolute value of the self-steepening parameter in a certain frequency range. (nonlinear optical phenomena)

  7. Production, Characterization, and Acceleration of Optical Microbunches

    SciTech Connect (OSTI)

    Sears, Christopher M.S.; /Stanford U. /SLAC

    2008-06-20

    Optical microbunches with a spacing of 800 nm have been produced for laser acceleration research. The microbunches are produced using a inverse Free-Electron-Laser (IFEL) followed by a dispersive chicane. The microbunched electron beam is characterized by coherent optical transition radiation (COTR) with good agreement to the analytic theory for bunch formation. In a second experiment the bunches are accelerated in a second stage to achieve for the first time direct net acceleration of electrons traveling in a vacuum with visible light. This dissertation presents the theory of microbunch formation and characterization of the microbunches. It also presents the design of the experimental hardware from magnetostatic and particle tracking simulations, to fabrication and measurement of the undulator and chicane magnets. Finally, the dissertation discusses three experiments aimed at demonstrating the IFEL interaction, microbunch production, and the net acceleration of the microbunched beam. At the close of the dissertation, a separate but related research effort on the tight focusing of electrons for coupling into optical scale, Photonic Bandgap, structures is presented. This includes the design and fabrication of a strong focusing permanent magnet quadrupole triplet and an outline of an initial experiment using the triplet to observe wakefields generated by an electron beam passing through an optical scale accelerator.

  8. Sandia National Laboratories: Integrated Photonics Institute for

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

    Manufacturing Innovation (IP-IMI) Facebook Twitter YouTube Flickr RSS Microsystems Science & Technology Center Integrated Photonics Institute for Manufacturing Innovation (IP-IMI) Microsystems Science & Engineering Applications (MESA) Complex: A 400,000 Sq-Ft Development & Production Facility MSTC Banner Microsystems Science, Technology & Components IP-IMI IP-IMI Heterogeneous Integration IP-IMI Sandia is positioned to engage in partnerships in silicon and compound

  9. Dual concentric crystal low energy photon detector

    DOE Patents [OSTI]

    Guilmette, R.A.

    A photon detector for biological samples includes a block of NaI(T1) having a hole containing a thin walled cylinder of CsI(T1). At least three photo multiplier tubes are evenly spaced around the parameter of the block. Biological samples are placed within the hole, and emissions which are sensed by at least two of the photo multipliers from only the NaI(T1) detector are counted.

  10. Fabrication of photonic band gap materials

    DOE Patents [OSTI]

    Constant, Kristen; Subramania, Ganapathi S.; Biswas, Rana; Ho, Kai-Ming

    2002-01-15

    A method for forming a periodic dielectric structure exhibiting photonic band gap effects includes forming a slurry of a nano-crystalline ceramic dielectric or semiconductor material and monodisperse polymer microspheres, depositing a film of the slurry on a substrate, drying the film, and calcining the film to remove the polymer microspheres therefrom. The film may be cold-pressed after drying and prior to calcining. The ceramic dielectric or semiconductor material may be titania, and the polymer microspheres may be polystyrene microspheres.

  11. Anisotropy of two-photon absorption and free-carrier effect in nonpolar GaN

    SciTech Connect (OSTI)

    Fang, Yu; Zhou, Feng; Yang, Junyi; Wu, Xingzhi; Xiao, Zhengguo; Li, Zhongguo; Song, Yinglin

    2015-03-30

    We reported a systematic study about the anisotropic optical nonlinearities in bulk m-plane and a-plane GaN crystals by Z-scan and pump-probe with phase object methods under picosecond at 532 nm. The two-photon absorption coefficient, which was measured as a function of polarization angle, exhibited oscillation curves with a period of π/2, indicating a highly polarized optical third-order nonlinearity in both nonpolar GaN samples. Furthermore, free-carrier absorption revealed stronger hole-related absorption for E⊥c than for E//c probe polarization. In contrast, free-carrier refraction was found almost isotropic due to electron-related refraction in the isotropic conduction bands.

  12. Fano resonance control in a photonic crystal structure and its application to ultrafast switching

    SciTech Connect (OSTI)

    Yu, Yi Heuck, Mikkel; Hu, Hao; Xue, Weiqi; Peucheret, Christophe; Chen, Yaohui; Oxenløwe, Leif Katsuo; Yvind, Kresten; Mørk, Jesper

    2014-08-11

    We experimentally demonstrate a photonic crystal structure that allows easy and robust control of the Fano spectrum. Its operation relies on controlling the amplitude of light propagating along one of the light paths in the structure from which the Fano resonance is obtained. Short-pulse dynamic measurements show that besides drastically increasing the switching contrast, the transmission dynamics itself is strongly affected by the nature of the resonance. The influence of slow-recovery tails implied by a long carrier lifetime can thus be reduced using a Fano resonance due to a hitherto unrecognized reshaping effect of the nonlinear Fano transfer function. As an example, we present a system application of a Fano structure, demonstrating its advantages by the experimental realization of 10 Gbit/s all-optical modulation with optical control power less than 1 mW.

  13. Photon assisted current in molecular nanojunctions with novel types of contacts

    SciTech Connect (OSTI)

    Fainberg, Boris D.

    2014-03-31

    We propose new approaches to coherent control of transport via molecular junctions, which bypasses several of the hurdles to experimental realization of optically manipulated nanoelectronics noted in the previous literature. The first method is based on the application of intrinsic semiconductor contacts and optical frequencies below the semiconductor bandgap. Our analytical theory predicts a new phenomenon, referred to as coherent destruction of induced tunnelling, which extends the phenomenon of coherent destruction of tunnelling frequently discussed in the previous literature. We also propose to use graphene electrodes as a platform for effective photon assisted tunneling through molecular conduction nanojunctions. We predict dramatic increasing currents evaluated at side-band energies ∼nħω (n is a whole number) related to the modification of graphene gapless spectrum under the action of external electromagnetic field of frequency ω. Our results illustrate the potential of semiconductor and graphene contacts in coherent control of photocurrent.

  14. Growth and structure of a new photonic crystal: Chlorine substituted chalcone

    SciTech Connect (OSTI)

    Sarveshwara, H. P. Menezes, Anthoni Praveen; Raghavendra, S.; Dharmaprakash, S. M.; A, Jayarama

    2015-06-24

    A new organic photonic material 3-(2, 4-dichlorophenyl)-1-(2,5-dimethylthiophen-3-yl)propan-1-one(DMTP) has been synthesized and crystallised in acetone solution. The functional groups present in the new material were identified by FTIR spectroscopy. The material is optically transparent in the wavelength range of 400–1100 nm. The crystal structure of DMTP was determined by single crystal X-ray diffraction. The title compound crystallizes in monoclinic system with a centrosymmetric space group P2{sub 1}/c. The Z-scan study revealed that the optical limiting property exhibited by the DMTP molecule is based on the reverse saturable absorption phenomena.

  15. Two-photon decay of pseudoscalar quarkonia

    SciTech Connect (OSTI)

    Lansberg, J. P.; Pham, T. N.

    2008-08-29

    We report on our recent evaluation of the two-photon width of the pseudoscalar quarkonia, {eta}{sub c}(nS) and {eta}{sub b}(nS) in an approach based on Heavy-Quark Spin Symmetry (HQSS). To what concerns the 1S state {eta}{sub c}, our parameter-free computation agrees with experiments, as well as most of other theoretical works. On the other hand, our computation for the 2S-state looks 2S like a confirmation that there may exist an anomaly related to the decay of {eta}{sub c}{sup '}, especially in the light of the new preliminary result of the Belle collaboration. We also point out that the essentially model-independent ratio of {eta}{sub b} two-photon width to the {upsilon} leptonic width and the {eta}{sub b} two-photon width could be used to extract the strong coupling constant {alpha}{sub s}.

  16. String melting in a photon bath

    SciTech Connect (OSTI)

    Karouby, Johanna

    2013-10-01

    We compute the decay rate of a metastable cosmic string in contact with a thermal bath by finding the instanton solution. The new feature is that this decay rate is found in the context of non thermal scalar fields in contact with a thermal bath of photons. In general, to make topologically unstable strings stable, one can couple them to such a bath. The resulting plasma effect creates metastable configurations which can decay from the false vacuum to the true vacuum. In our specific set-up, the instanton computation is realized for the case of two out-of-equilibrium complex scalar fields: one is charged and coupled to the photon field, and the other is neutral. New effects coming from the thermal bath of photons make the radius of the nucleated bubble and most of the relevant physical quantities temperature-dependent. However, the temperature appears in a different way than in the purely thermal case, where all scalar fields are in thermal equilibrium. As a result of the tunneling, the core of the initial string melts while bubbles of true vacuum expand at the speed of light.

  17. Combined photonics and MEMs function demonstration

    SciTech Connect (OSTI)

    Blum, O.; Warren, M.E.; Hou, H.Q.; Choquette, K.D.; Rogers, M.S.; Sniegowski, J.J. [Sandia National Labs., Albuquerque, NM (United States); Carson, R.F. [Microoptical Devices, Inc., Albuquerque, NM (United States)

    1998-01-01

    The authors have recently demonstrated two prototypes where photonics and microelectromechanical system (MEMs) technologies have been integrated to show proof-of-principle functionality for weapon surety functions. These activities are part of a program which is exploring the miniaturization of electromechanical components for making weapon systems safer. Such miniaturization can lead to a low-cost, small, high-performance ``systems-on-a-chip``, and have many applications ranging from advanced military systems to large-volume commercial markets like automobiles, rf or land-based communications networks and equipment, or commercial electronics. One of the key challenges in realization of the microsystem is integration of several technologies including digital electronics; analog and rf electronics, optoelectronics (light emitting and detecting devices and circuits), sensors and actuators, and advanced packaging technologies. In this work the authors describe efforts in integrating MEMs and photonic functions and the fabrication constraints on both system components. Here, they discuss two examples of integration of MEMs and a photonic device. In the first instance, a MEMs locking device pin is driven by a voltage generated by photovoltaic cells connected in series, which are driven by a laser. In the second case, a VCSEL emitting at 1.06 {micro}m is packaged together with a metallized MEMs shutter. By appropriate alignment to the opening in the shutter, the VCSEL is turned on and off by the movement of the Si chopper wheel.

  18. Photonic-magnonic crystals: Multifunctional periodic structures for magnonic and photonic applications

    SciTech Connect (OSTI)

    K?os, J. W. Krawczyk, M.; Dadoenkova, Yu. S.; Dadoenkova, N. N.; Lyubchanskii, I. L.

    2014-05-07

    We investigate the properties of a photonic-magnonic crystal, a complex multifunctional one-dimensional structure with magnonic and photonic band gaps in the GHz and PHz frequency ranges for spin waves and light, respectively. The system consists of periodically distributed dielectric magnetic slabs of yttrium iron garnet and nonmagnetic spacers with an internal structure of alternating TiO{sub 2} and SiO{sub 2} layers which form finite-size dielectric photonic crystals. We show that the spin-wave coupling between the magnetic layers, and thus the formation of the magnonic band structure, necessitates a nonzero in-plane component of the spin-wave wave vector. A more complex structure perceived by light is evidenced by the photonic miniband structure and the transmission spectra in which we have observed transmission peaks related to the repetition of the magnetic slabs in the frequency ranges corresponding to the photonic band gaps of the TiO{sub 2}/SiO{sub 2} stack. Moreover, we show that these modes split to very high sharp (a few THz wide) subpeaks in the transmittance spectra. The proposed novel multifunctional artificial crystals can have interesting applications and be used for creating common resonant cavities for spin waves and light to enhance the mutual influence between them.

  19. Anisotropic Electron-Photon and Electron-Phonon Interactions in Black Phosphorus

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

    Ling, Xi; Huang, Shengxi; Hasdeo, Eddwi; Liang, Liangbo; Parkin, William; Tatsumi, Yuki; Nugraha, Ahmad; Puretzky, Alexander A; Das, Paul; Sumpter, Bobby G; et al

    2016-03-10

    Orthorhombic black phosphorus (BP) and other layered materials, such as gallium telluride (GaTe) and tin selenide (SnSe), stand out among two-dimensional (2D) materials owing to their anisotropic in-plane structure. This anisotropy adds a new dimension to the properties of 2D materials and stimulates the development of angle-resolved photonics and electronics. However, understanding the effect of anisotropy has remained unsatisfactory to-date, as shown by a number of inconsistencies in the recent literatures. We use angle-resolved absorption and Raman spectroscopies to investigate the role of anisotropy on the electron-photon and electron-phonon interactions in BP. We highlight a non-trivial dependence between anisotropies andmore » flake thickness, photon and phonon energies. We show that once understood, the anisotropic optical absorption appears to be a reliable and simple way to identify the crystalline orientation of BP, which cannot be determined from Raman spectroscopy without the explicit consideration of excitation wavelength and flake thickness, as commonly used previously.« less

  20. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    Large Telescope Adaptive Optics Systems Citation Details In-Document Search Title: Optical Design for Extremely Large Telescope Adaptive Optics Systems You are accessing a ...

  1. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    ThesisDissertation: Optical Design for Extremely Large Telescope Adaptive Optics Systems Citation Details In-Document Search Title: Optical Design for Extremely Large Telescope ...

  2. Problems associated with large scale personnel monitoring of photons using lithium-fluoride TLD-100

    SciTech Connect (OSTI)

    Not Available

    1985-01-01

    The dosimetric properties of a large batch of lithium fluoride TLD-100 dosimeters when exposed to photons for total absorbed doses in the region from 0.1-10 mGy (10-100 mr) have been examined in this work. This region is of particular importance because in many operational health physics situations the majority (>90%) of all recorded absorbed doses to personnel lie in this region. With the possibility that occupational radiation dose limits may be reduced in the future accurate monitoring of individuals in this region will be of prime importance. The purpose of this thesis was to point out several effects which could compromise accurate dosimetric measurements in this region and to suggest some methods to minimize them. These effects include the effect of TLD batch composition, overresponse of the dosimeter to low energy photons, dose rate effects, the effects of storing the dosimeter before readout, and possible interference from ultraviolet and radiofrequency radiation. Each of these items can cause errors which can range up to 70%, depending on the total absorbed dose and the particulars of the radiation exposure. One effect which is of extreme interest is the induction of a thermoluminescent signal by radiofrequency radiation. Although this effect can cause gross errors in estimating the ionizing dose, it opens the possibility that LiF or another phosphor may have an application as a non-ionizing radiation dosimeter.

  3. Latching micro optical switch

    DOE Patents [OSTI]

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

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

  4. Breakdown of Angular Momentum Selection Rules in High Pressure Optical Pumping Experiments

    SciTech Connect (OSTI)

    Lancor, B.; Wyllie, R.; Walker, T. G.; Babcock, E.

    2010-08-20

    We present measurements, by using two complementary methods, of the breakdown of atomic angular momentum selection rules in He-broadened Rb vapor. Atomic dark states are rendered weakly absorbing due to fine-structure mixing during Rb-He collisions. The effect substantially increases the photon demand for optical pumping of dense vapors.

  5. Photon assisted processes: Probability amplitudes for the absorption and emission of photons and dc-photocurrents

    SciTech Connect (OSTI)

    Micu, C.; Racolta, D.; Papp, E.

    2014-11-24

    In this paper one deals with the derivation of probability amplitudes characterizing the photon assisted injection of electrons in a two-terminal quantum conductor. For this purpose one accounts for spatially constant but time dependent periodic voltages applied on an Ohmic contact. Resorting to the discrete Fourier transform provides the probability amplitudes for the emission and absorption of photons in terms of squared Bessel functions of the first kind and integer order. Several kinds of ac-pulses like sinusoidal and dc+sinusoidal are assumed. Mean square values concerning photon numbers have been discussed in some more detail. Time averages of squared time dependent classical currents and leading corrections to the rescaled dc-photocurrent have also been accounted for.

  6. Methodology and apparatus for diffuse photon imaging

    DOE Patents [OSTI]

    Feng, S.C.; Zeng, F.; Zhao, H.L.

    1997-12-09

    Non-invasive near infrared optical medical imaging devices for both hematoma detection in the brain and early tumor detection in the breast is achieved using image reconstruction which allows a mapping of the position dependent contrast diffusive propagation constants, which are related to the optical absorption coefficient and scattering coefficient in the tissue, at near infrared wavelengths. Spatial resolutions in the range of 5 mm for adult brain sizes and breast sizes can be achieved. The image reconstruction utilizes WKB approximation on most probable diffusion paths which has as lowest order approximation the straight line-of-sight between the plurality of sources and the plurality of detectors. The WKB approximation yields a set of linear equations in which the contrast optical absorption coefficients are the unknowns and for which signals can be generated to produce a pixel map of the contrast optical resolution of the scanned tissue. 58 figs.

  7. Methodology and apparatus for diffuse photon mimaging

    DOE Patents [OSTI]

    Feng, Shechao C.; Zeng, Fanan; Zhao, Hui-Lin

    1997-12-09

    Non-invasive near infrared optical medical imaging devices for both hematoma detection in the brain and early tumor detection in the breast is achieved using image reconstruction which allows a mapping of the position dependent contrast diffusive propagation constants, which are related to the optical absorption coefficient and scattering coefficient in the tissue, at near infrared wavelengths. Spatial resolutions in the range of 5 mm for adult brain sizes and breast sizes can be achieved. The image reconstruction utilizes WKB approximation on most probable diffusion paths which has as lowest order approximation the straight line-of-sight between the plurality of sources and the plurality of detectors. The WKB approximation yields a set of linear equations in which the contrast optical absorption coefficients are the unknowns and for which signals can be generated to produce a pixel map of the contrast optical resolution of the scanned tissue.

  8. Experiment Hall & Beamline | Advanced Photon Source

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

    1104-m-circumference optical bench. The hall floor is made of 1-ft-thick poured concrete. Usual practice in poured concrete construction is the use of evenly spaced cuts in...

  9. Active optical zoom system

    DOE Patents [OSTI]

    Wick, David V.

    2005-12-20

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

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

    SciTech Connect (OSTI)

    Roland Winston Joseph O'Gallagher

    2005-01-15

    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

  11. Escape fraction of ionizing photons during reionization: Effects due to supernova feedback and runaway ob stars

    SciTech Connect (OSTI)

    Kimm, Taysun; Cen, Renyue

    2014-06-20

    The fraction of hydrogen ionizing photons escaping from galaxies into the intergalactic medium is a critical ingredient in the theory of reionization. We use two zoomed-in, high-resolution (4 pc), cosmological radiation hydrodynamic simulations with adaptive mesh refinement to investigate the impact of two physical mechanisms (supernova, SN, feedback, and runaway OB stars) on the escape fraction (f {sub esc}) at the epoch of reionization (z ? 7). We implement a new, physically motivated SN feedback model that can approximate the Sedov solutions at all (from the free expansion to snowplow) stages. We find that there is a significant time delay of about ten million years between the peak of star formation and that of escape fraction, due to the time required for the build-up and subsequent destruction of the star-forming cloud by SN feedback. Consequently, the photon number-weighted mean escape fraction for dwarf galaxies in halos of mass 10{sup 8}-10{sup 10.5} M {sub ?} is found to be ?f{sub esc}??11%, although instantaneous values of f {sub esc} > 20% are common when star formation is strongly modulated by the SN explosions. We find that the inclusion of runaway OB stars increases the mean escape fraction by 22% to ?f{sub esc}??14%. As SNe resulting from runaway OB stars tend to occur in less dense environments, the feedback effect is enhanced and star formation is further suppressed in halos with M{sub vir}?10{sup 9} M{sub ?} in the simulation with runaway OB stars compared with the model without them. While both our models produce enough ionizing photons to maintain a fully ionized universe at z ? 7 as observed, a still higher amount of ionizing photons at z ? 9 appears necessary to accommodate the high observed electron optical depth inferred from cosmic microwave background observations.

  12. High bandwidth optical mount

    DOE Patents [OSTI]

    Bender, D.A.; Kuklo, T.

    1994-11-08

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

  13. High bandwidth optical mount

    DOE Patents [OSTI]

    Bender, Donald A.; Kuklo, Thomas

    1994-01-01

    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.

  14. Measurement of the Isolated Prompt Photon Production Cross Section in pp Collisions at sqrt(s) = 7 TeV

    SciTech Connect (OSTI)

    Khachatryan, Vardan; et al.

    2011-02-01

    The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E_T-gamma in pp collisions at sqrt(s)=7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9 inverse picobarns. Photons are required to have a pseudorapidity |eta_gamma|<1.45 and E_T-gamma > 21 GeV, covering the kinematic region 0.006 < x_T < 0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.

  15. THE {gamma}-RAY EMISSION REGION IN THE FANAROFF-RILEY II RADIO GALAXY 3C 111

    SciTech Connect (OSTI)

    Grandi, P.; Torresi, E.; Stanghellini, C. E-mail: torresi@iasfbo.inaf.it

    2012-05-20

    The broad-line radio galaxy 3C 111, characterized by a Fanaroff-Riley II (FRII) radio morphology, is one of the sources of the misaligned active galactic nucleus sample, consisting of radio galaxies and steep spectrum radio quasars, recently detected by the Fermi Large Area Telescope (LAT). Our analysis of the 24 month {gamma}-ray light curve shows that 3C 111 was only occasionally detected at high energies. It was bright at the end of 2008 and faint, below the Fermi-LAT sensitivity threshold, for the rest of the time. A multifrequency campaign of 3C 111, ongoing in the same period, revealed an increase of the millimeter, optical, and X-ray fluxes in 2008 September-November, interpreted by Chatterjee et al. as due to the passage of a superluminal knot through the jet core. The temporal coincidence of the millimeter-optical-X-ray outburst with the GeV activity suggests a cospatiality of the events, allowing, for the first time, the localization of the {gamma}-ray dissipative zone in an FRII jet. We argue that the GeV photons of 3C 111 are produced in a compact region confined within 0.1 pc and at a distance of about 0.3 pc from the black hole.

  16. EXCESS OPTICAL ENHANCEMENT OBSERVED WITH ARCONS FOR EARLY CRAB GIANT PULSES

    SciTech Connect (OSTI)

    Strader, M. J.; Mazin, B. A.; Spiro Jaeger, G. V.; Gwinn, C. R.; Meeker, S. R.; Szypryt, P.; Van Eyken, J. C.; Marsden, D.; Walter, A. B.; Ulbricht, G.; Johnson, M. D.; O'Brien, K.; Stoughton, C.; Bumble, B.

    2013-12-10

    We observe an extraordinary link in the Crab pulsar between the enhancement of an optical pulse and the timing of the corresponding giant radio pulse. At optical through infrared wavelengths, our observations use the high time resolution of ARray Camera for Optical to Near-IR Spectrophotometry, a unique superconducting energy-resolving photon-counting array at the Palomar 200 inch telescope. At radio wavelengths, we observe with the Robert C. Byrd Green Bank Telescope and the Green Bank Ultimate Pulsar Processing Instrument backend. We see an 11.3% ± 2.5% increase in peak optical flux for pulses that have an accompanying giant radio pulse arriving near the peak of the optical main pulse, in contrast to a 3.2% ± 0.5% increase when an accompanying giant radio pulse arrives soon after the optical peak. We also observe that the peak of the optical main pulse is 2.8% ± 0.8% enhanced when there is a giant radio pulse accompanying the optical interpulse. We observe no statistically significant spectral differences between optical pulses accompanied by and not accompanied by giant radio pulses. Our results extend previous observations of optical-radio correlation to the time and spectral domains. Our refined temporal correlation suggests that optical and radio emission are indeed causally linked, and the lack of spectral differences suggests that the same mechanism is responsible for all optical emission.

  17. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, R.; Kotter, D.

    1994-04-26

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

  18. Reflective optical imaging system

    DOE Patents [OSTI]

    Shafer, David R.

    2000-01-01

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

  19. Fiber optic micro accelerometer

    DOE Patents [OSTI]

    Swierkowski, Steve P.

    2005-07-26

    An accelerometer includes a wafer, a proof mass integrated into the wafer, at least one spring member connected to the proof mass, and an optical fiber. A Fabry-Perot cavity is formed by a partially reflective surface on the proof mass and a partially reflective surface on the end of the optical fiber. The two partially reflective surfaces are used to detect movement of the proof mass through the optical fiber, using an optical detection system.

  20. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, Richard; Kotter, Dale

    1994-01-01

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

  1. Effective atomic numbers and mass attenuation coefficients of some thermoluminescent dosimetric compounds for total photon interaction

    SciTech Connect (OSTI)

    Shivaramu; Amutha, R.; Ramprasath, V.

    1999-05-01

    Effective atomic numbers for total gamma-ray interaction with some selected thermoluminescent dosimetric compounds such as barium acetate, barium sulfate, calcium carbonate, calcium sulfate, calcium sulfate dihydrate, cadmium sulfate (anhydrous), cadmium sulfate, strontium sulfate, and lithium fluoride have been calculated in the 1-keV to 20-MeV energy region. Experimental mass attenuation coefficients and effective atomic numbers for these compounds at selected photon energies of 26.3, 33.2, 59.54, and 661.6 keV have been obtained from good geometry transmission measurements and compared with theoretical values. The effect of absorption edge on effective atomic numbers and its variation with energy, and nonvalidity of the Bragg`s mixture rule at incident photon energies closer to the absorption edges of constituent elements of compounds are discussed.

  2. Hidden symmetries, null geodesics, and photon capture in the Sen black hole

    SciTech Connect (OSTI)

    Hioki, Kenta; Miyamoto, Umpei

    2008-08-15

    Important classes of null geodesics and hidden symmetries in the Sen black hole are investigated. First, we obtain the principal null geodesics and circular photon orbits. Then, an irreducible rank-two Killing tensor and a conformal Killing tensor are derived, which represent the hidden symmetries. Analyzing the properties of Killing tensors, we clarify why the Hamilton-Jacobi and wave equations are separable in this spacetime. We also investigate the gravitational capture of photons by the Sen black hole and compare the result with those by the various charged/rotating black holes and naked singularities in the Kerr-Newman family. For these black holes and naked singularities, we show the capture regions in a two dimensional impact parameter space (or equivalently the 'shadows' observed at infinity) to form a variety of shapes such as the disk, circle, dot, arc, and their combinations.

  3. Report on the first VLHC photon stop cryogenic design experiment

    SciTech Connect (OSTI)

    Michael Geynisman et al.

    2003-09-15

    As part of Fermilab's study of a Very Large Hadron Collider, a water-cooled photon stop was proposed as a device to intercept the synchrotron radiation emitted by the high-energy proton beams in the high field superconducting magnets with minimal plug-cooling power. Photon stops are radiation absorbers operating at room temperature that protrude into the beam tube at the end of each bending magnet to scrape the synchrotron light emitted by the beam one magnet up-stream. Among the technological challenges regarding photon stops is their cryo-design. The photon stop is water-cooled and operates in a cryogenic environment. A careful cryo-design is therefore essential to enable operation at minimum heat transfer between the room temperature sections and the cryogenic parts. A photon stop cryo-design was developed and a prototype was built. This paper presents the results of the cryogenic experiments conducted on the first VLHC photon stop prototype.

  4. The Heavy Photon Search experiment at Jefferson Laboratory

    SciTech Connect (OSTI)

    De Napoli, Marzio

    2015-06-01

    Many beyond Standard Model theories predict a new massive gauge boson, a.k.a. 'dark' or 'heavy photon', directly coupling to hidden sector particles with dark charge. The heavy photon is expected to mix with the Standard Model photon through kinetic mixing and therefore couple weakly to normal charge. The Heavy Photon Search (HPS) experiment will search for the heavy photon at the Thomas Jefferson National Accelerator Facility (JLab), in the mass range 20-1000 MeV/c2 and coupling to electric charge ϵ2 = α'/α in the range 10-5 to 10-10. HPS will look for the e+e- decay channel of heavy photons radiated by electron Bremsstrahlung, employing both invariant mass search and detached vertexing techniques. The experiment employs a compact forward spectrometer comprising silicon microstrip detectors for vertexing and tracking and an electromagnetic calorimeter for particle identification and triggering.

  5. Production of photons in relativistic heavy-ion collisions

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

    Jean -Francois Paquet; Denicol, Gabriel S.; Shen, Chun; Luzum, Matthew; Schenke, Bjorn; Jeon, Sangyong; Gale, Charles

    2016-04-18

    In this work it is shown that the use of a hydrodynamical model of heavy-ion collisions which incorporates recent developments, together with updated photon emission rates, greatly improves agreement with both ALICE and PHENIX measurements of direct photons, supporting the idea that thermal photons are the dominant source of direct photon momentum anisotropy. The event-by-event hydrodynamical model uses the impact parameter dependent Glasma model (IP-Glasma) initial states and includes, for the first time, both shear and bulk viscosities, along with second-order couplings between the two viscosities. Furthermore, the effect of both shear and bulk viscosities on the photon rates ismore » studied, and those transport coefficients are shown to have measurable consequences on the photon momentum anisotropy.« less

  6. Optical orientation of azo dye molecules in a thin solid film upon nonlinear excitation by femtosecond laser pulses

    SciTech Connect (OSTI)

    Yongseok, Jung; Kozenkov, V M; Magnitskiy, Sergey A; Nagorskiy, Nikolay M

    2006-11-30

    The orientation of molecules in an amorphous pure azo dye film upon nonlinear excitation is detected for the first time. The simultaneous increase and decrease in the film transmission by a factor of 2.5 for orthogonal polarisations of probe radiation indicated the appearance of orientation order in the film caused by the reorientation of azo dye molecules. Due to a high photostability of the AD-1 azo dye demonstrated in single-photon experiments and a high efficiency of nonlinear orientation obtained in experiments with femtosecond pulses, this dye can be widely used in three-dimensional nanophotonic devices such as photonic crystals, optical computers, and optical memory. (letters)

  7. Search for new phenomena in events with at least three photons collected in pp collisions at √s = 8 TeV with the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2016-04-01

    Results of a search for new phenomena in events with at least three photons are reported. Data from proton–proton collisions at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb-1, were collected with the ATLAS detector at the LHC. The observed data are well described by the Standard Model. Limits at the 95 % confidence level on new phenomena are presented based on the rate of events in an inclusive signal region and a restricted signal region targeting the rare decay Z→3γ, as well as di-photon and tri-photon resonance searches. For a Standard Model Higgsmore » boson decaying to four photons via a pair of intermediate pseudoscalar particles (a), limits are found to be σ× BR (h→aa)× BR (a→γγ)2<10-3σSM for 10 GeV a< 62 GeV. Finally, limits are also presented for Higgs boson-like scalars (H) for mH> 125 GeV, and for a Z' decaying to three photons via Z'→a+γ→3γ. Additionally, the observed limit on the branching ratio of the Z boson decay to three photons is found to be BR(Z→3γ)<2.2×10-6, a result five times stronger than the previous result from LEP.« less

  8. National Ignition Facility & Photon Science

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

    33 National Ignition Facility & Photon Science Frequently asked Questions Q. What is NIF? A. The National Ignition Facility (NIF) is the world's largest and highest-energy laser. NIF's 192 intense laser beams are capable of delivering to their target more than 100 times the energy of any previous laser system. experiments on the path to ignition began in 2010. during full-scale ignition experiments, NIF will direct up to 1.8 million joules of ultraviolet laser energy in billionth-of-a-second

  9. National Ignition Facility & Photon Science

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

    1 National Ignition Facility & Photon Science limitless energy the Promise of Limitless energy harnessing the energy of the sun and stars to meet the earth's energy needs has been a decades-long scientific and engineering quest. While a self-sustaining fusion burn has been achieved for brief periods under experimental conditions, the amount of energy that went into creating it was greater than the amount of energy it generated. There was no energy gain, which is essential if fusion energy is

  10. Energy Upgrade of the Siam Photon Source

    SciTech Connect (OSTI)

    Rugmai, S.; Rujirawat, S.; Hoyes, G. G.; Prawanta, S.; Kwankasem, A.; Siriwattanapitoon, S.; Suradet, N.; Pimol, P.; Junthong, N.; Boonsuya, S.; Janpuang, P.; Prawatsri, P.; Klysubun, P.

    2007-01-19

    The energy upgrade of the storage ring is part of the plans to develop x-ray production capability of the Siam Photon Source. Simulations have been carried out. The bending magnet power supply has been replaced. Energy of the injected 1 GeV beam from the injector is then ramped up 20% in the storage ring. Studies for modification of bending magnet poles have been done to evaluate possibility of further increasing the beam energy to 1.4 GeV in the future. Studies of the energy upgrade plan and details of energy ramping process, together with beam measurements are presented.

  11. Super-collimation by axisymmetric photonic crystals

    SciTech Connect (OSTI)

    Purlys, V.; Gailevi?ius, D.; Peckus, M.; Gadonas, R.; Maigyte, L.; Staliunas, K.

    2014-06-02

    We propose and experimentally show the mechanism of beam super-collimation by axisymmetric photonic crystals, specifically by periodic (in propagation direction) structure of layers of concentric rings. The physical mechanism behind the effect is an inverse scattering cascade of diffracted wave components back into on- and near-axis angular field components, resulting in substantial enhancement of intensity of these components. We explore the super-collimation by numerical calculations and prove it experimentally. We demonstrate experimentally the axial field enhancement up to 7 times in terms of field intensity.

  12. Method and apparatus for use of III-nitride wide bandgap semiconductors in optical communications

    DOE Patents [OSTI]

    Hui, Rongqing; Jiang,Hong-Xing; Lin, Jing-Yu

    2008-03-18

    The present disclosure relates to the use of III-nitride wide bandgap semiconductor materials for optical communications. In one embodiment, an optical device includes an optical waveguide device fabricated using a III-nitride semiconductor material. The III-nitride semiconductor material provides for an electrically controllable refractive index. The optical waveguide device provides for high speed optical communications in an infrared wavelength region. In one embodiment, an optical amplifier is provided using optical coatings at the facet ends of a waveguide formed of erbium-doped III-nitride semiconductor materials.

  13. Photon Science Seminar Series | Stanford Synchrotron Radiation Lightsource

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

    Photon Science Seminar Series SLAC's Photon Science Seminar Series brings together scientists from SLAC's Linac Coherent Light Source, Stanford Synchrotron Radiation Lightsource, Photon Science and Accelerator directorates, including researchers from the Center for Sustainable Energy through Catalysis and two joint SLAC-Stanford institutes: the Stanford Institute for Materials and Energy Sciences and the Pulse Institute for Ultrafast Energy Science. The seminar series' main goals are to

  14. Method of accelerating photons by a relativistic plasma wave

    DOE Patents [OSTI]

    Dawson, John M.; Wilks, Scott C.

    1990-01-01

    Photons of a laser pulse have their group velocity accelerated in a plasma as they are placed on a downward density gradient of a plasma wave of which the phase velocity nearly matches the group velocity of the photons. This acceleration results in a frequency upshift. If the unperturbed plasma has a slight density gradient in the direction of propagation, the photon frequencies can be continuously upshifted to significantly greater values.

  15. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    Symmetry Breaking of H2 Dissociation by a Single Photon Print A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of

  16. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    Symmetry Breaking of H2 Dissociation by a Single Photon Print A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of

  17. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    Symmetry Breaking of H2 Dissociation by a Single Photon Print A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of

  18. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    Symmetry Breaking of H2 Dissociation by a Single Photon Print A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of

  19. Photon Induced Positron Annihilation (PIPA) - Energy Innovation Portal

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

    Startup America Startup America Find More Like This Return to Search Photon Induced Positron Annihilation (PIPA) Idaho National Laboratory Contact INL About This Technology Technology Marketing Summary This suite of patents define a non-destructive testing technology that uses photon induced positrons to measure volumetric changes in the lattice structure of metals, polymers, and ceramic components. The system uses a linear accelerator or calibrated photon source, a germanium (Ge) detector and a

  20. Thermophotovoltaic energy conversion using photonic bandgap selective emitters

    DOE Patents [OSTI]

    Gee, James M.; Lin, Shawn-Yu; Fleming, James G.; Moreno, James B.

    2003-06-24

    A method for thermophotovoltaic generation of electricity comprises heating a metallic photonic crystal to provide selective emission of radiation that is matched to the peak spectral response of a photovoltaic cell that converts the radiation to electricity. The use of a refractory metal, such as tungsten, for the photonic crystal enables high temperature operation for high radiant flux and high dielectric contrast for a full 3D photonic bandgap, preferable for efficient thermophotovoltaic energy conversion.

  1. Nikon PTIPHOT-88 Optical Microscope

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

    OPTIPHOT-88 Optical Microscope micro1.jpg (69171 bytes)

  2. Low attenuation optical fiber of deuterated polymer

    SciTech Connect (OSTI)

    Beasley, J.K.; Beckerbauer, R.; Schleinitz, H.M.; Wilson, F.C.

    1985-04-16

    Light-transmitting optical fiber having a core of a (deuterated acrylate) polymer selected from the group consisting of a deuterated methacrylate homopolymer, a deuterated methacrylate copolymer and a deuterated methacrylate/acrylate copolymer which exhibits remarkably high transmission of light in the visible and at certain wavelengths in the near-infrared region of the spectrum.

  3. Results from the Solar Hidden Photon Search (SHIPS)

    SciTech Connect (OSTI)

    Schwarz, Matthias; Knabbe, Ernst-Axel; Lindner, Axel; Redondo, Javier; Ringwald, Andreas; Schneide, Magnus; Susol, Jaroslaw; Wiedemann, Günter

    2015-08-07

    We present the results of a search for transversely polarised hidden photons (HPs) with ∼3 eV energies emitted from the Sun. These hypothetical particles, known also as paraphotons or dark sector photons, are theoretically well motivated for example by string theory inspired extensions of the Standard Model. Solar HPs of sub-eV mass can convert into photons of the same energy (photon ↔ HP oscillations are similar to neutrino flavour oscillations). At SHIPS this would take place inside a long light-tight high-vacuum tube, which tracks the Sun. The generated photons would then be focused into a low-noise photomultiplier at the far end of the tube. Our analysis of 330 h of data (and 330 h of background characterisation) reveals no signal of photons from solar hidden photon conversion. We estimate the rate of newly generated photons due to this conversion to be smaller than 25 mHz/m{sup 2} at the 95% C.L. Using this and a recent model of solar HP emission, we set stringent constraints on χ, the coupling constant between HPs and photons, as a function of the HP mass.

  4. Absorption and emission properties of photonic crystals and metamateri...

    Office of Scientific and Technical Information (OSTI)

    ThesisDissertation: Absorption and emission properties of photonic crystals and metamaterials Citation Details In-Document Search Title: Absorption and emission properties of ...

  5. APS Engineering Support Division (AES) | Advanced Photon Source

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

    APS Engineering Support Division (AES) The APS Engineering Support Division provides reliable operations and technical support to the Advanced Photon Source user community. AES...

  6. Knot Undulator to Generate Linearly Polarized Photons with Low...

    Office of Scientific and Technical Information (OSTI)

    pure linearly polarized photons in the third generation synchrotron radiation facilities. ... Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 43 ...

  7. Direct photon production from viscous quark-gluon plasma

    SciTech Connect (OSTI)

    Chaudhuri, A. K.; Sinha, Bikash

    2011-03-15

    We simulate direct photon production in the evolution of viscous quark-gluon plasma medium. Photons from Compton and annihilation processes are considered. The viscous effect on photon production is very strong and reliable simulation is possible only in a limited p{sub T} range. For minimally viscous fluid ({eta}/s=0.08), direct photons can be reliably computed only up to p{sub T}{<=}1.3 GeV. With reduced viscosity ({eta}/s=0.04), the limit increases to p{sub T}{<=}2 GeV.

  8. Two-photon physics as a probe of hadron dynamics

    SciTech Connect (OSTI)

    Brodsky, S.J.

    1981-05-01

    Two-photon collisions provide an ideal laboratory for testing many features of quantum chromodynamics, especially the interplay between the vector-meson-dominated and point-like hadronic interactions of the photon. A number of QCD applications are discussed, including: jet and single-particle production at large transverse momentum; the photon structure function and its relationship to the ..gamma.. ..-->.. q anti q wave function; and the possible role of gluonium states in the ..gamma gamma.. ..-->.. rho/sup 0/rho/sup 0/ channel. Evidence that even low momentum transfer photon-hadron interactions are sensitive to the point-like ..gamma.. ..-->.. q anti q coupling is discussed.

  9. NEAR-IR TWO PHOTON MICROSCOPY IMAGING OF SILICA NANOPARTICLES...

    Office of Scientific and Technical Information (OSTI)

    NANOPARTICLES FUNCTIONALIZED WITH ISOLATED SENSITIZED Yb(III) CENTERS Citation Details In-Document Search Title: NEAR-IR TWO PHOTON MICROSCOPY IMAGING OF SILICA NANOPARTICLES ...

  10. The low and intermediate mass dilepton and photon results

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

    Ruan, Lijuan

    2014-10-18

    I summarize and discuss some of the experimental results on the low and intermediate mass dileptons and direct photons presented at Quark Matter 2014.

  11. Photon Enhanced Thermionic Emission for Solar Energy Harvesting...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Photon Enhanced Thermionic Emission for Solar Energy Harvesting Final Report to the Global Climate and Energy Project Citation Details In-Document Search Title: ...

  12. Enhancing the Sensitivity of Label-free Silicon Photonic Biosensors...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Journal Name: ACS Photonics; Journal Volume: 1; Journal Issue: 7 Research Org: Oak Ridge National Laboratory (ORNL); Center for Nanophase Materials Sciences ...

  13. Reducing the losses of optical metamaterials

    SciTech Connect (OSTI)

    Fang, Anan

    2010-12-15

    The field of metamaterials is driven by fascinating and far-reaching theoretical visions, such as perfect lenses, invisibility cloaking, and enhanced optical nonlinearities. However, losses have become the major obstacle towards real world applications in the optical regime. Reducing the losses of optical metamaterials becomes necessary and extremely important. In this thesis, two approaches are taken to reduce the losses. One is to construct an indefinite medium. Indefinite media are materials where not all the principal components of the permittivity and permeability tensors have the same sign. They do not need the resonances to achieve negative permittivity, {var_epsilon}. So, the losses can be comparatively small. To obtain indefinite media, three-dimensional (3D) optical metallic nanowire media with different structures are designed. They are numerically demonstrated that they are homogeneous effective indefinite anisotropic media by showing that their dispersion relations are hyperbolic. Negative group refraction and pseudo focusing are observed. Another approach is to incorporate gain into metamaterial nanostructures. The nonlinearity of gain is included by a generic four-level atomic model. A computational scheme is presented, which allows for a self-consistent treatment of a dispersive metallic photonic metamaterial coupled to a gain material incorporated into the nanostructure using the finite-difference time-domain (FDTD) method. The loss compensations with gain are done for various structures, from 2D simplified models to 3D realistic structures. Results show the losses of optical metamaterials can be effectively compensated by gain. The effective gain coefficient of the combined system can be much larger than the bulk gain counterpart, due to the strong local-field enhancement.

  14. Fiber optic vibration sensor

    DOE Patents [OSTI]

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

    1995-01-10

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

  15. Fiber optic vibration sensor

    DOE Patents [OSTI]

    Dooley, Joseph B.; Muhs, Jeffrey D.; Tobin, Kenneth W.

    1995-01-01

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

  16. Omnidirectional fiber optic tiltmeter

    DOE Patents [OSTI]

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

    1983-06-30

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

  17. Hyper-Ramsey spectroscopy of optical clock transitions

    SciTech Connect (OSTI)

    Yudin, V. I.; Taichenachev, A. V.; Oates, C. W.; Barber, Z. W.; Lemke, N. D.; Ludlow, A. D.; Sterr, U.; Lisdat, Ch.; Riehle, F.

    2010-07-15

    We present nonstandard optical Ramsey schemes that use pulses individually tailored in duration, phase, and frequency to cancel spurious frequency shifts related to the excitation itself. In particular, the field shifts and their uncertainties can be radically suppressed (by two to four orders of magnitude) in comparison with the usual Ramsey method (using two equal pulses) as well as with single-pulse Rabi spectroscopy. Atom interferometers and optical clocks based on two-photon transitions, heavily forbidden transitions, or magnetically induced spectroscopy could significantly benefit from this method. In the latter case, these frequency shifts can be suppressed considerably below a fractional level of 10{sup -17}. Moreover, our approach opens the door for high-precision optical clocks based on direct frequency comb spectroscopy.

  18. Optical gating of perylene bisimide fluorescence usingdithienylcyclop...

    Office of Scientific and Technical Information (OSTI)

    The emission of millions of fluorescence photons from a chromophore is controlled by the absorption of a few tens of photons in a photochromic molecule. The parameters that ...

  19. Narrow-band single photon emission at room temperature based on a single nitrogen-vacancy center coupled to an all-fiber-cavity

    SciTech Connect (OSTI)

    Albrecht, Roland; Bommer, Alexander; Becher, Christoph; Pauly, Christoph; Mücklich, Frank; Schell, Andreas W.; Engel, Philip; Benson, Oliver; Schröder, Tim; Reichel, Jakob

    2014-08-18

    We report the realization of a device based on a single Nitrogen-Vacancy (NV) center in diamond coupled to a fiber-cavity for use as single photon source (SPS). The device consists of two concave mirrors each directly fabricated on the facets of two optical fibers and a preselected nanodiamond containing a single NV center deposited onto one of these mirrors. Both, cavity in- and out-put are directly fiber-coupled, and the emission wavelength is easily tunable by variation of the separation of the two mirrors with a piezo-electric crystal. By coupling to the cavity, we achieve an increase of the spectral photon rate density by two orders of magnitude compared to free-space emission of the NV center. With this work, we establish a simple all-fiber based SPS with promising prospects for the integration into photonic quantum networks.

  20. Transparent electrode for optical switch

    DOE Patents [OSTI]

    Goldhar, Julius; Henesian, Mark A.

    1986-01-01

    A low pressure gas electrode utilizing ionized gas in a glow discharge regime forms a transparent electrode for electro-optical switches. The transparent electrode comprises a low pressure gas region on both sides of the crystal. When the gas is ionized, e.g., by a glow discharge in the low pressure gas, the plasma formed is a good conductor. The gas electrode acts as a highly uniform conducting electrode. Since the plasma is transparent to a high energy laser beam passing through the crystal, the electrode is a transparent electrode. A crystal exposed from two sides to such a plasma can be charged up uniformly to any desired voltage. The plasma can be created either by the main high voltage pulser used to charge up the crystal or by auxiliary discharges or external sources of ionization. A typical configuration utilizes 10 torr argon in the discharge region adjacent to each crystal face.