Sample records for junction adjacent layers

  1. Fabrication of magnetic tunnel junctions with epitaxial and textured ferromagnetic layers

    DOE Patents [OSTI]

    Chang, Y. Austin (Middleton, WI); Yang, Jianhua Joshua (Madison, WI)

    2008-11-11T23:59:59.000Z

    This invention relates to magnetic tunnel junctions and methods for making the magnetic tunnel junctions. The magnetic tunnel junctions include a tunnel barrier oxide layer sandwiched between two ferromagnetic layers both of which are epitaxial or textured with respect to the underlying substrate upon which the magnetic tunnel junctions are grown. The magnetic tunnel junctions provide improved magnetic properties, sharper interfaces and few defects.

  2. Microstructure of Josephson junctions: Effect on supercurrent transport in YBCO grain boundary and barrier layer junctions

    SciTech Connect (OSTI)

    Merkle, K.L.; Huang, Y.

    1998-01-01T23:59:59.000Z

    The electric transport of high-temperature superconductors, such as YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} (YBCO), can be strongly restricted by the presence of high-angle grain boundaries (GB). This weak-link behavior is governed by the macroscopic GB geometry and the microscopic grain boundary structure and composition at the atomic level. Whereas grain boundaries present a considerable impediment to high current applications of high T{sub c} materials, there is considerable commercial interest in exploiting the weak-link-nature of grain boundaries for the design of microelectronic devices, such as superconducting quantum interference devices (SQUIDs). The Josephson junctions which form the basis of this technology can also be formed by introducing artificial barriers into the superconductor. The authors have examined both types of Josephson junctions by EM techniques in an effort to understand the connection between microstructure/chemistry and electrical transport properties. This knowledge is a valuable resource for the design and production of improved devices.

  3. Properties of planar Nb/{alpha}-Si/Nb Josephson junctions with various degrees of doping of the {alpha}-Si layer

    SciTech Connect (OSTI)

    Gudkov, A. L., E-mail: gudkov@niifp.ru [Lukin Scientific Research Institute of Physical Problems, ZAO Kompelst (Russian Federation); Kupriyanov, M. Yu. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Samus', A. N. [Lukin Scientific Research Institute of Physical Problems, ZAO Kompelst (Russian Federation)

    2012-05-15T23:59:59.000Z

    The properties of Nb/{alpha}-Si/Nb planar Josephson junctions with various degrees of doping of the amorphous silicon layer are experimentally studied. Tungsten is used as a doping impurity. The properties of the Josephson junctions are shown to change substantially when the degree of doping of the {alpha}-Si layer changes: a current transport mechanism and the shape of the current-voltage characteristic of the junctions change. Josephson junctions with SNS-type conduction are formed in the case of a fully degenerate {alpha}-Si layer. The properties of such junctions are described by a classical resistive model. Josephson junctions with a resonance mechanism of current transport through impurity centers are formed at a lower degree of doping of the {alpha}-Si layer. The high-frequency properties of such junctions are shown to change. The experimental results demonstrate that these junctions are close to SINIS-type Josephson junctions.

  4. Nanotube junctions

    DOE Patents [OSTI]

    Crespi, Vincent Henry (Darien, IL); Cohen, Marvin Lou (Berkeley, CA); Louie, Steven Gwon Sheng (Berkeley, CA); Zettl, Alexander Karlwalter (Kensington, CA)

    2003-01-01T23:59:59.000Z

    The present invention comprises a new nanoscale metal-semiconductor, semiconductor-semiconductor, or metal-metal junction, designed by introducing topological or chemical defects in the atomic structure of the nanotube. Nanotubes comprising adjacent sections having differing electrical properties are described. These nanotubes can be constructed from combinations of carbon, boron, nitrogen and other elements. The nanotube can be designed having different indices on either side of a junction point in a continuous tube so that the electrical properties on either side of the junction vary in a useful fashion. For example, the inventive nanotube may be electrically conducting on one side of a junction and semiconducting on the other side. An example of a semiconductor-metal junction is a Schottky barrier. Alternatively, the nanotube may exhibit different semiconductor properties on either side of the junction. Nanotubes containing heterojunctions, Schottky barriers, and metal-metal junctions are useful for microcircuitry.

  5. Effect of magnetic field on quasiparticle branches of intrinsic Josephson junctions with ferromagnetic layer.

    SciTech Connect (OSTI)

    Ozyuzer, L.; Ozdemir, M.; Kurter, C.; Hinks, D. G.; Gray, K. E. (Materials Science Division); (Izmir Inst. of Tech.)

    2007-01-01T23:59:59.000Z

    The interlayer tunneling spectroscopy has been performed on micron-sized mesa arrays of HgBr{sub 2} intercalated superconducting Bi2212 single crystals. A ferromagnetic multilayer (Au/Co/Au) is deposited on top of the mesas. The spin-polarized current is driven along the c-axis of the mesas through a ferromagnetic Co layer and the hysteretic quasiparticle branches are observed at 4.2 K. Magnetic field evolution of hysteretic quasiparticle branches is obtained to examine the effect of injected spin-polarized current on intrinsic Josephson junction characteristics. It is observed that there is a gradual distribution in quasiparticle branches with the application of magnetic field and increasing field reduces the switching current progressively.

  6. TRIPLE-JUNCTION A-SI SOLAR CELLS WITH HEAVILY DOPED THIN INTERFACE LAYERS AT THE TUNNEL W. Wang, H. Povolny, W. Du, X.B. Liao and X. Deng

    E-Print Network [OSTI]

    Deng, Xunming

    TRIPLE-JUNCTION A-SI SOLAR CELLS WITH HEAVILY DOPED THIN INTERFACE LAYERS AT THE TUNNEL JUNCTIONS W of Toledo, Toledo, OH 43606 USA ABSTRACT Triple-junction a-Si based solar cells, having a structure of SS cells and between the middle and bottom component cells on the efficiency of triple- junction solar

  7. Highly transparent low capacitance plasma enhanced atomic layer deposition Al{sub 2}O{sub 3}-HfO{sub 2} tunnel junction engineering

    SciTech Connect (OSTI)

    El Hajjam, Khalil, E-mail: khalil.el-hajjam@insa-lyon.fr [INL, INSA, UMR CNRS 5270, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex, France and Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada); Baboux, Nicolas; Calmon, Francis [INL, INSA, UMR CNRS 5270, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Souifi, Abdelkader [Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada); Poncelet, Olivier; Francis, Laurent A. [ICTEAM, ELEN, UCL, Place du Levant 3, 1348 Louvain-la-Neuve (Belgium); Ecoffey, Serge; Drouin, Dominique [Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec, Canada and Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada)

    2014-01-15T23:59:59.000Z

    The development of metallic single electron transistor (SET) depends on the downscaling and the electrical properties of its tunnel junctions. These tunnel junctions should insure high tunnel current levels, low thermionic current, and low capacitance. The authors use atomic layer deposition to fabricate Al{sub 2}O{sub 3} and HfO{sub 2} thin layers. Tunnel barrier engineering allows the achievement of low capacitance Al{sub 2}O{sub 3} and HfO{sub 2} tunnel junctions using optimized annealing and plasma exposure conditions. Different stacks were designed and fabricated to increase the transparency of the tunnel junction while minimizing thermionic current. This tunnel junction is meant to be integrated in SET to enhance its electrical properties (e.g., operating temperature, I{sub ON}/I{sub OFF} ratio)

  8. High-field electroluminescence in semiconductor tunnel junctions with a Mn-doped GaAs layer

    SciTech Connect (OSTI)

    Hai, Pham Nam [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-0033 (Japan); Yatsui, Takashi; Ohtsu, Motoichi; Tanaka, Masaaki [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Nanophotonics Research Center, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-09-21T23:59:59.000Z

    We investigated high-field electroluminescence (EL) in semiconductor tunnel junctions with a Mn-doped GaAs layer (here, referred to as GaAs:Mn). Besides the band-gap emission of GaAs, the EL spectra show visible light emissions with two peaks at 1.94?eV and 2.19?eV, which are caused by d-d transitions of the Mn atoms excited by hot electrons. The threshold voltages for band-gap and visible light EL in the tunnel junctions with a GaAs:Mn electrode are 1.3?V higher than those of GaAs:Mn excited by hot holes in reserve biased p{sup +}-n junctions, which is consistent with the hot carrier transport in the band profiles of these structures. Our EL results at room temperature show that the electron temperature in GaAs:Mn can be as high as ?700?K for a low input electrical power density of 0.4?W/cm{sup 2}, while the lattice temperature of the GaAs:Mn layer can be kept at 340?K.

  9. Heat transfer coefficient saturation in superconducting Nb tunnel junctions contacted to a NbTiN circuit and an Au energy relaxation layer

    E-Print Network [OSTI]

    Selig, Stefan; Jacobs, Karl; Schultz, Michael; Honingh, Netty

    2014-01-01T23:59:59.000Z

    In this paper we present the experimental realization of a Nb tunnel junction connected to a high-gap superconducting NbTiN embedding circuit. We investigate relaxation of nonequilibrium quasiparticles in a small volume Au layer between the Nb tunnel junction and the NbTiN circuit. We find a saturation in the effective heat-transfer coefficient consistent with a simple theoretical model. This saturation is determined by the thickness of the Au layer. Our findings are important for the design of the ideal Au energy relaxation layer for practical SIS heterodyne mixers and we suggest two geometries, one, using a circular Au layer and, two, using a half-circular Au layer. Our work is concluded with an outlook of our future experiments.

  10. BI-LAYER p-n JUNCTION INTERCONNECTIONS FOR COAL BASED SOLID OXIDE FUEL CELLS

    SciTech Connect (OSTI)

    Srikanth Gopalan

    2005-01-29T23:59:59.000Z

    In this report, a new approach for lower operating temperature solid oxide fuel cells (SOFCs) interconnections (IC) consisting of a bi-layer structure is proposed and analyzed. The bi-layer structure consists of a p-type layer exposed to cathodic gas (air/oxygen) and an n-type layer exposed to anodic gas (fuel). It is theoretically shown that the interfacial oxygen partial pressure which is an important design variable, is dependent primarily on the oxygen partial pressure gradient across the IC, the low level oxygen conductivities of the two layers and is largely independent of their electronic conductivities and the total current density through the IC material. Experimental difficulties in fabricating bi-layer structures are presently being addressed.

  11. Formation of Porous Layers by Electrochemical Etching of Germanium and Gallium Arsenide for Cleave Engineered Layer Transfer (CELT) Application in High Efficiency Multi-Junction Solar Cells

    E-Print Network [OSTI]

    Fong, David Michael

    2012-01-01T23:59:59.000Z

    III! V Multijunction Solar Cells,” (2003). J. F. Geisz, etEfficiency Multi-Junction Solar Cells A thesis submitted inEfficiency Multi-Junction Solar Cells By David Michael Fong

  12. Magnetic tunnel junctions for magnetic field sensor by using CoFeB sensing layer capped with MgO film

    SciTech Connect (OSTI)

    Takenaga, Takashi, E-mail: takenaga@leap.or.jp; Tsuzaki, Yosuke; Yoshida, Chikako; Yamazaki, Yuichi; Hatada, Akiyoshi; Nakabayashi, Masaaki; Iba, Yoshihisa; Takahashi, Atsushi; Noshiro, Hideyuki; Tsunoda, Koji; Aoki, Masaki; Furukawa, Taisuke; Fukumoto, Hiroshi; Sugii, Toshihiro [Low-power Electronics Association and Project (LEAP), Tsukuba 305-8569 (Japan)

    2014-05-07T23:59:59.000Z

    We evaluated MgO-based magnetic tunnel junctions (MTJs) for magnetic field sensors with spin-valve-type structures in the CoFeB sensing layer capped by an MgO film in order to obtain both top and bottom interfaces of MgO/CoFeB exhibiting interfacial perpendicular magnetic anisotropy (PMA). Hysteresis of the CoFeB sensing layer in these MTJs annealed at 275?°C was suppressed at a thickness of the sensing layer below 1.2?nm by interfacial PMA. We confirmed that the CoFeB sensing layers capped with MgO suppress the thickness dependences of both the magnetoresistance ratio and the magnetic behaviors of the CoFeB sensing layer more than that of the MTJ with a Ta capping layer. MgO-based MTJs with MgO capping layers can improve the controllability of the characteristics for magnetic field sensors.

  13. Broadband and omnidirectional anti-reflection layer for III/V multi-junction solar cells

    E-Print Network [OSTI]

    Diedenhofen, Silke L; Haverkamp, Erik; Bauhuis, Gerard; Schermer, John; Rivas, Jaime Gómez; 10.1016/j.solmat.2012.02.022

    2012-01-01T23:59:59.000Z

    We report a novel graded refractive index antireflection coating for III/V quadruple solar cells based on bottom-up grown tapered GaP nanowires. We have calculated the photocurrent density of an InGaP-GaAs-InGaAsP-InGaAs solar cell with a MgF2/ZnS double layer antireflection coating and with a graded refractive index coating. The photocurrent density can be increased by 5.9 % when the solar cell is coated with a graded refractive index layer with a thickness of 1\\mu m. We propose to realize such a graded refractive index layer by growing tapered GaP nanowires on III/V solar cells. For a first demonstration of the feasibility of the growth of tapered nanowires on III/V solar cells, we have grown tapered GaP nanowires on AlInP/GaAs substrates. We show experimentally that the reflection from the nanowire coated substrate is reduced and that the transmission into the substrate is increased for a broad spectral and angular range.

  14. Superconductive tunnel junction integrated circuit

    SciTech Connect (OSTI)

    Jillie, D.W. Jr.; Smith, L.N.

    1984-02-07T23:59:59.000Z

    Josephson Junction integrated circuits of the current injection type and magnetically controlled type utilize a superconductive layer that forms both Josephson Junction electrode for the Josephson Junction devices on the integrated circuit as well as a ground plane for the integrated circuit. Large area Josephson Junctions are utilized for effecting contact to lower superconductive layers and islands are formed in superconductive layers to provide isolation between the groundplane function and the Josephson Junction electrode function as well as to effect crossovers. A superconductor-barrier-superconductor trilayer patterned by local anodization is also utilized with additional layers formed thereover. Methods of manufacturing the embodiments of the invention are disclosed.

  15. Conductance enhancement due to interface magnons in electron-beam evaporated MgO magnetic tunnel junctions with CoFeB free layer deposited at different pressure

    SciTech Connect (OSTI)

    Guo, P.; Yu, G. Q.; Wei, H. X.; Han, X. F., E-mail: jiafengfeng@aphy.iphy.ac.cn, E-mail: xfhan@aphy.iphy.ac.cn [Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Li, D. L.; Feng, J. F., E-mail: jiafengfeng@aphy.iphy.ac.cn, E-mail: xfhan@aphy.iphy.ac.cn [Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); CRANN and School of Physics, Trinity College, Dublin 2 (Ireland); Kurt, H. [CRANN and School of Physics, Trinity College, Dublin 2 (Ireland); Department of Engineering Physics, Istanbul Medeniyet University, 34720 Istanbul (Turkey); Chen, J. Y.; Coey, J. M. D. [CRANN and School of Physics, Trinity College, Dublin 2 (Ireland)

    2014-10-21T23:59:59.000Z

    Electron-beam evaporated MgO-based magnetic tunnel junctions have been fabricated with the CoFeB free layer deposited at Ar pressure from 1 to 4?mTorr, and their tunneling process has been studied as a function of temperature and bias voltage. By changing the growth pressure, the junction dynamic conductance dI/dV, inelastic electron tunneling spectrum d{sup 2}I/dV{sup 2}, and tunneling magnetoresistance vary with temperature. Moreover, the low-energy magnon cutoff energy E{sub C} derived from the conductance versus temperature curve agrees with interface magnon energy obtained directly from the inelastic electron tunneling spectrum, which demonstrates that interface magnons are involved in the electron tunneling process, opening an additional conductance channel and thus enhancing the total conductance.

  16. Spin dependent transport properties of Mn-Ga/MgO/Mn-Ga magnetic tunnel junctions with metal(Mg, Co, Cr) insertion layer

    SciTech Connect (OSTI)

    Liang, S. H.; Tao, L. L.; Liu, D. P., E-mail: dpliu@iphy.ac.cn; Han, X. F., E-mail: xfhan@iphy.ac.cn [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Lu, Y. [Institut Jean Lamour, UMR 7198, CNRS-Nancy Université, BP 239, 54506 Vandoeuvre (France)

    2014-04-07T23:59:59.000Z

    We report a first principles theoretical investigation of spin polarized quantum transport in Mn{sub 2}Ga/MgO/Mn{sub 2}Ga and Mn{sub 3}Ga/MgO/Mn{sub 3}Ga magnetic tunneling junctions (MTJs) with the consideration of metal(Mg, Co, Cr) insertion layer effect. By changing the concentration of Mn, our calculation shows a considerable disparity in transport properties: A tunneling magnetoresistance (TMR) ratio of 852% was obtained for Mn{sub 2}Ga-based MTJs, however, only a 5% TMR ratio for Mn{sub 3}Ga-based MTJs. In addition, the influence of insertion layer has been considered in our calculation. We found the Co insertion layer can increase the TMR of Mn{sub 2}Ga-based MTJ to 904%; however, the Cr insertion layer can decrease the TMR by 668%; A negative TMR ratio can be obtained with Mg insertion layer. Our work gives a comprehensive understanding of the influence of different insertion layer in Mn-Ga based MTJs. It is proved that, due to the transmission can be modulated by the interfacial electronic structure of insertion, the magnetoresistance ratio of Mn{sub 2}Ga/MgO/Mn{sub 2}Ga MTJ can be improved by inserting Co layer.

  17. Current-induced switching of magnetic tunnel junctions: Effects of field-like spin-transfer torque, pinned-layer magnetization orientation, and temperature

    SciTech Connect (OSTI)

    Tiwari, R. K.; Jhon, M. H.; Ng, N.; Gan, C. K., E-mail: ganck@ihpc.a-star.edu.sg [Institute of High Performance Computing, Agency for Science, Technology and Research, 1 Fusionopolis Way, 16-16 Connexis, Singapore 138632 (Singapore); Srolovitz, D. J. [Department of Materials Science, Engineering, Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

    2014-01-13T23:59:59.000Z

    We study current-induced switching in magnetic tunnel junctions in the presence of a field-like spin-transfer torque and titled pinned-layer magnetization in the high current limit at finite temperature. We consider both the Slonczewski and field-like torques with coefficients a{sub J} and b{sub J}, respectively. At finite temperatures, ?=b{sub J}/a{sub J}=±1 leads to a smaller mean switching time compared that with ?=0. The reduction of switching time in the presence of the field-like term is due to the alignment effect (for ?>0) and the initial torque effect.

  18. Method of manufacturing Josephson junction integrated circuits

    SciTech Connect (OSTI)

    Jillie Jr., D. W.; Smith, L. N.

    1985-02-12T23:59:59.000Z

    Josephson junction integrated circuits of the current injection type and magnetically controlled type utilize a superconductive layer that forms both Josephson junction electrode for the Josephson junction devices on the integrated circuit as well as a ground plane for the integrated circuit. Large area Josephson junctions are utilized for effecting contact to lower superconductive layers and islands are formed in superconductive layers to provide isolation between the groudplane function and the Josephson junction electrode function as well as to effect crossovers. A superconductor-barrier-superconductor trilayer patterned by local anodization is also utilized with additional layers formed thereover. Methods of manufacturing the embodiments of the invention are disclosed.

  19. Interface magnetism of Co{sub 2}FeGe Heusler alloy layers and magnetoresistance of Co{sub 2}FeGe/MgO/Fe magnetic tunnel junctions

    SciTech Connect (OSTI)

    Tanaka, M. A., E-mail: mtanaka@nitech.ac.jp; Maezaki, D.; Ishii, T.; Okubo, A.; Mibu, K. [Department of Engineering Physics, Electronics and Mechanics, Nagoya Institute of Technology, Nagoya, Aichi 466-8555 (Japan); Hiramatsu, R.; Ono, T. [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2014-10-28T23:59:59.000Z

    The interface magnetism between Co{sub 2}FeGe Heusler alloy layers and MgO layers was investigated using {sup 57}Fe Mössbauer spectroscopy. Interface-sensitive samples, where the {sup 57}Fe isotope was used only for the interfacial atomic layer of the Co{sub 2}FeGe layer on the MgO layer, were prepared using atomically controlled alternate deposition. The {sup 57}Fe Mössbauer spectra of the interface-sensitive samples at room temperature were found similar to those of the bulk-sensitive Co{sub 2}FeGe films in which the {sup 57}Fe isotope was distributed throughout the films. On the other hand, the tunnel magnetoresistance effect of magnetic tunnel junctions with Co{sub 2}FeGe layers as the ferromagnetic electrodes showed strong reduction at room temperature. These results indicate that the strong temperature dependence of the tunneling magnetoresistance of magnetic tunnel junctions using Heusler alloy electrodes cannot be attributed simply to the reduction of the magnetization at the interfaces between the Heusler alloy and insulator layers.

  20. Josephson junction

    SciTech Connect (OSTI)

    Wendt, Joel R. (Albuquerque, NM); Plut, Thomas A. (Albuquerque, NM); Martens, Jon S. (Sunnyvale, CA)

    1995-01-01T23:59:59.000Z

    A novel method for fabricating nanometer geometry electronic devices is described. Such Josephson junctions can be accurately and reproducibly manufactured employing photolithographic and direct write electron beam lithography techniques in combination with aqueous etchants. In particular, a method is described for manufacturing planar Josephson junctions from high temperature superconducting material.

  1. Josephson junction

    SciTech Connect (OSTI)

    Wendt, J.R.; Plut, T.A.; Martens, J.S.

    1995-05-02T23:59:59.000Z

    A novel method for fabricating nanometer geometry electronic devices is described. Such Josephson junctions can be accurately and reproducibly manufactured employing photolithographic and direct write electron beam lithography techniques in combination with aqueous etchants. In particular, a method is described for manufacturing planar Josephson junctions from high temperature superconducting material. 10 figs.

  2. Triple-Junction a-Si Solar Cells Deposited With Improved Intrinsic Layers X. Deng, W. Wang, X.B. Liao, S. Han, H. Povolny, X.B. Xiang, and W. Du

    E-Print Network [OSTI]

    Deng, Xunming

    -Si/a-SiGe/a-SiGe triple cells with 12.7% initial efficiency. Figure 1 shows the IV curve of the 12.7% triple cell, GD585.7%. Figure 1 IV curve of a UT fabricated triple cell, showing 12.7% initial, active-area efficiency. Figure 2Triple-Junction a-Si Solar Cells Deposited With Improved Intrinsic Layers X. Deng, W. Wang, X

  3. Four-Junction Solar Cell with 40% Target Efficiency Fabricated by Wafer Bonding and Layer Transfer: Final Technical Report, 1 January 2005 - 31 December 2007

    SciTech Connect (OSTI)

    Atwater, H. A.

    2008-11-01T23:59:59.000Z

    We realized high-quality InGaP/GaAs 2-junction top cells on Ge/Si, InGaAs/InP bottom cells, direct-bond series interconnection of tandem cells, and modeling of bonded 3- and 4-junction device performance.

  4. Duality in Josephson Junction Arrays

    E-Print Network [OSTI]

    Ya. M. Blanter; Rosario Fazio; Gerd Schoen

    1997-01-30T23:59:59.000Z

    Various properties of mesoscopic two-dimensional Josephson junction arrays are reviewed. Particular attention is paid to structure of the topological excitations, charges and vortices, which are shown to be dual to each other. This duality persists in the presence of external magnetic fields and offset charges, which influence vortices and charges in an equivalent way. A double-layer junction array is also considered, where an even further reaching duality is discovered.

  5. Cambridge Grand Junction transit implementation : alternatives, scheduling, cost, and performance

    E-Print Network [OSTI]

    Iglesias Cuervo, Jesus

    2012-01-01T23:59:59.000Z

    The Grand Junction railroad lies at the heart of East Cambridge adjacent to the Kendall Square business district and the Massachusetts Institute of Technology campus. Over the last one hundred years the railroad has gone ...

  6. Multi-junction solar cell device

    DOE Patents [OSTI]

    Friedman, Daniel J. (Lakewood, CO); Geisz, John F. (Wheat Ridge, CO)

    2007-12-18T23:59:59.000Z

    A multi-junction solar cell device (10) is provided. The multi-junction solar cell device (10) comprises either two or three active solar cells connected in series in a monolithic structure. The multi-junction device (10) comprises a bottom active cell (20) having a single-crystal silicon substrate base and an emitter layer (23). The multi-junction device (10) further comprises one or two subsequent active cells each having a base layer (32) and an emitter layer (23) with interconnecting tunnel junctions between each active cell. At least one layer that forms each of the top and middle active cells is composed of a single-crystal III-V semiconductor alloy that is substantially lattice-matched to the silicon substrate (22). The polarity of the active p-n junction cells is either p-on-n or n-on-p. The present invention further includes a method for substantially lattice matching single-crystal III-V semiconductor layers with the silicon substrate (22) by including boron and/or nitrogen in the chemical structure of these layers.

  7. low Si p+-n junctions fabricated by focused ion beam Ga+ implantation through thin Ti and TiSi2 layers

    E-Print Network [OSTI]

    Steckl, Andrew J.

    metals and silicide layers, in conjunction with rapid thermal annealing (RTA) to complete metal silicides and it forms uniform thin films on Si. Most of the current research involving salicide+ implantation through Ti metal (ITM) and TiSi, (ITS) layers, followed by rapid thermal annealing (RTA), has been

  8. Holographic Josephson Junctions

    SciTech Connect (OSTI)

    Horowitz, Gary T.; Santos, Jorge E.; Way, Benson [Department of Physics, University of California, Santa Barbara, California 93106-4030 (United States)

    2011-06-03T23:59:59.000Z

    We construct a gravitational dual of a Josephson junction. Calculations on the gravity side reproduce the standard relation between the current across the junction and the phase difference of the condensate. We also study the dependence of the maximum current on the temperature and size of the junction and reproduce familiar results.

  9. A Holographic Josephson Junction

    E-Print Network [OSTI]

    Gary T. Horowitz; Jorge E. Santos; Benson Way

    2012-02-23T23:59:59.000Z

    We construct a gravitational dual of a Josephson junction. Calculations on the gravity side reproduce the standard relation between the current across the junction and the phase difference of the condensate. We also study the dependence of the maximum current on the temperature and size of the junction and reproduce familiar results.

  10. Complementary junction heterostructure field-effect transistor

    DOE Patents [OSTI]

    Baca, Albert G. (Albuquerque, NM); Drummond, Timothy J. (Albuquerque, NM); Robertson, Perry J. (Albuquerque, NM); Zipperian, Thomas E. (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    A complimentary pair of compound semiconductor junction heterostructure field-effect transistors and a method for their manufacture are disclosed. The p-channel junction heterostructure field-effect transistor uses a strained layer to split the degeneracy of the valence band for a greatly improved hole mobility and speed. The n-channel device is formed by a compatible process after removing the strained layer. In this manner, both types of transistors may be independently optimized. Ion implantation is used to form the transistor active and isolation regions for both types of complimentary devices. The invention has uses for the development of low power, high-speed digital integrated circuits.

  11. Complementary junction heterostructure field-effect transistor

    DOE Patents [OSTI]

    Baca, A.G.; Drummond, T.J.; Robertson, P.J.; Zipperian, T.E.

    1995-12-26T23:59:59.000Z

    A complimentary pair of compound semiconductor junction heterostructure field-effect transistors and a method for their manufacture are disclosed. The p-channel junction heterostructure field-effect transistor uses a strained layer to split the degeneracy of the valence band for a greatly improved hole mobility and speed. The n-channel device is formed by a compatible process after removing the strained layer. In this manner, both types of transistors may be independently optimized. Ion implantation is used to form the transistor active and isolation regions for both types of complimentary devices. The invention has uses for the development of low power, high-speed digital integrated circuits. 10 figs.

  12. Nonlocal macroscopic quantum tunneling and quantum terahertz electrodynamics in layered superconductors: Theory and simulations

    E-Print Network [OSTI]

    Nori, Franco

    in stacks of intrinsic Josephson junctions. Due to the long-range interaction between junctions in layered of Josephson junctions. We also propose a simple analytical formula to estimate the MQT escape rate. Moreover junction, stacks of intrinsic Josephson junctions are strongly coupled along the direction perpen- dicular

  13. Magnetic field penetration in a long Josephson junction imbedded in a wide stripline

    E-Print Network [OSTI]

    Wallraff, Andreas

    Magnetic field penetration in a long Josephson junction imbedded in a wide stripline Andreas Franz The dependence of the first critical field of long linear and annular Josephson junctions on the width A Josephson junction is formed by two superconductors separated by a thin oxide layer allowing the tunneling

  14. Holographic SIS Josephson Junction

    E-Print Network [OSTI]

    Wang, Yong-Qiang; Cai, Rong-Gen; Takeuchi, Shingo; Zhang, Hai-Qing

    2012-01-01T23:59:59.000Z

    We construct a holographic model for the superconductor-insulator-superconductor (SIS) Josephson junction at zero temperature by considering a complex scalar field coupled with a U(1) gauge field in the four dimensional Anti de Sitter soliton background. As a result, we successfully reproduce many characteristic features of the Josephson junction in condensed matter physics, such as the sine relation between the DC current and the phase difference across the junction.

  15. Method for shallow junction formation

    DOE Patents [OSTI]

    Weiner, Kurt H. (San Jose, CA)

    1996-01-01T23:59:59.000Z

    A doping sequence that reduces the cost and complexity of forming source/drain regions in complementary metal oxide silicon (CMOS) integrated circuit technologies. The process combines the use of patterned excimer laser annealing, dopant-saturated spin-on glass, silicide contact structures and interference effects creates by thin dielectric layers to produce source and drain junctions that are ultrashallow in depth but exhibit low sheet and contact resistance. The process utilizes no photolithography and can be achieved without the use of expensive vacuum equipment. The process margins are wide, and yield loss due to contact of the ultrashallow dopants is eliminated.

  16. Method for shallow junction formation

    DOE Patents [OSTI]

    Weiner, K.H.

    1996-10-29T23:59:59.000Z

    A doping sequence is disclosed that reduces the cost and complexity of forming source/drain regions in complementary metal oxide silicon (CMOS) integrated circuit technologies. The process combines the use of patterned excimer laser annealing, dopant-saturated spin-on glass, silicide contact structures and interference effects creates by thin dielectric layers to produce source and drain junctions that are ultrashallow in depth but exhibit low sheet and contact resistance. The process utilizes no photolithography and can be achieved without the use of expensive vacuum equipment. The process margins are wide, and yield loss due to contact of the ultrashallow dopants is eliminated. 8 figs.

  17. Josephson junction element

    SciTech Connect (OSTI)

    Kawabe, U.; Tarutani, Y.; Yamada, H.

    1982-03-09T23:59:59.000Z

    A sandwich-type josephson junction element wherein a counter electrode is made of a mo-re alloy which contains 10-90 atomic-% of re. The josephson junction element has a high operating temperature, and any deterioration thereof attributed to a thermal cycle is not noted.

  18. Three-junction solar cell

    DOE Patents [OSTI]

    Ludowise, Michael J. (Cupertino, CA)

    1986-01-01T23:59:59.000Z

    A photovoltaic solar cell is formed in a monolithic semiconductor. The cell contains three junctions. In sequence from the light-entering face, the junctions have a high, a medium, and a low energy gap. The lower junctions are connected in series by one or more metallic members connecting the top of the lower junction through apertures to the bottom of the middle junction. The upper junction is connected in voltage opposition to the lower and middle junctions by second metallic electrodes deposited in holes 60 through the upper junction. The second electrodes are connected to an external terminal.

  19. Low temperature junction growth using hot-wire chemical vapor deposition

    DOE Patents [OSTI]

    Wang, Qi; Page, Matthew; Iwaniczko, Eugene; Wang, Tihu; Yan, Yanfa

    2014-02-04T23:59:59.000Z

    A system and a process for forming a semi-conductor device, and solar cells (10) formed thereby. The process includes preparing a substrate (12) for deposition of a junction layer (14); forming the junction layer (14) on the substrate (12) using hot wire chemical vapor deposition; and, finishing the semi-conductor device.

  20. Holographic SIS Josephson Junction

    E-Print Network [OSTI]

    Yong-Qiang Wang; Yu-Xiao Liu; Rong-Gen Cai; Shingo Takeuchi; Hai-Qing Zhang

    2012-09-23T23:59:59.000Z

    We construct a holographic model for the superconductor-insulator-superconductor (SIS) Josephson junction at zero temperature by considering a complex scalar field coupled with a Maxwell field in the four-dimensional anti-de Sitter soliton background. From the gravity side we reproduce the sine relation between the Josephson current and the phase difference across the junction. We also study the dependence of the maximal current on the dimension of the condensate operator and on the width of the junction, and obtain expected results.

  1. Improved method of preparing p-i-n junctions in amorphous silicon semiconductors

    DOE Patents [OSTI]

    Madan, A.

    1984-12-10T23:59:59.000Z

    A method of preparing p/sup +/-i-n/sup +/ junctions for amorphous silicon semiconductors includes depositing amorphous silicon on a thin layer of trivalent material, such as aluminum, indium, or gallium at a temperature in the range of 200/sup 0/C to 250/sup 0/C. At this temperature, the layer of trivalent material diffuses into the amorphous silicon to form a graded p/sup +/-i junction. A layer of n-type doped material is then deposited onto the intrinsic amorphous silicon layer in a conventional manner to finish forming the p/sup +/-i-n/sup +/ junction.

  2. Modeling Schottky barrier SINIS junctions

    E-Print Network [OSTI]

    Freericks, Jim

    : cond-mat/0001269 J. K. Freericks, Georgetown University, Josephson Junction talk, 2001 #12;Josephson). J. K. Freericks, Georgetown University, Josephson Junction talk, 2001 S I S I I V V Ic #12 University, Josephson Junction talk, 2001 S N S I I V V Ic #12;Digital Electronics and RSFQ logic · Rapid

  3. Spin Torques in Magnetic and Superconducting Tunnel Junctions

    E-Print Network [OSTI]

    Hoffman, Silas Eli

    2012-01-01T23:59:59.000Z

    Josephson Junctions . . . . . . . . . . . . . . . . . . . . .Nonlinear Dynamics in a Magnetic Josephson Junction . . . .in a magnetic Josephson junction. ” Phys. Rev. B, 86:

  4. Enhancement of tunnel magnetoresistance in magnetic tunnel junction by a superlattice barrier

    SciTech Connect (OSTI)

    Chen, C. H.; Hsueh, W. J., E-mail: hsuehwj@ntu.edu.tw [Nanomagnetism Group, Department of Engineering Science and Ocean Engineering, National Taiwan University, 1, Sec. 4, Roosevelt Road, Taipei 10660, Taiwan (China)

    2014-01-27T23:59:59.000Z

    Tunnel magnetoresistance of magnetic tunnel junction improved by a superlattice barrier composed of alternate layers of a nonmagnetic metal and an insulator is proposed. The forbidden band of the superlattice is used to predict the low transmission range in the superlattice barrier. By forbidding electron transport in the anti-parallel configuration, the tunnel magnetoresistance is enhanced in the superlattice junction. The results show that the tunnel magnetoresistance ratio for a superlattice magnetic tunnel junction is greater than that for traditional single or double barrier junctions.

  5. A market analysis for high efficiency multi-junction solar cells grown on SiGe

    E-Print Network [OSTI]

    Judkins, Zachara Steele

    2007-01-01T23:59:59.000Z

    Applications, markets and a cost model are presented for III-V multi-junction solar cells built on compositionally graded SiGe buffer layers currently being developed by professors Steven Ringell of Ohio State University ...

  6. Thermally activated switching in spin-flop tunnel junctions V. Korenivskia

    E-Print Network [OSTI]

    Haviland, David

    -closed multilayers, consisting of two ferromagnetic layers separated by a thin nonmagnetic spacer, have been proposed of similar lateral dimensions. Spin-flop junctions with writing circuits have been fab- ricated by methods

  7. High temperature superconductor step-edge Josephson junctions using Ti-Ca-Ba-Cu-O

    SciTech Connect (OSTI)

    Ginley, D.S.; Hietala, V.M.; Hohenwarter, G.K.G.; Martens, J.S.; Plut, T.A.; Tigges, C.P.; Vawter, G.A.; Zipperian, T.E.

    1994-10-25T23:59:59.000Z

    A process is disclosed for formulating non-hysteretic and hysteretic Josephson junctions using HTS materials which results in junctions having the ability to operate at high temperatures while maintaining high uniformity and quality. The non-hysteretic Josephson junction is formed by step-etching a LaAlO[sub 3] crystal substrate and then depositing a thin film of TlCaBaCuO on the substrate, covering the step, and forming a grain boundary at the step and a subsequent Josephson junction. Once the non-hysteretic junction is formed the next step to form the hysteretic Josephson junction is to add capacitance to the system. In the current embodiment, this is accomplished by adding a thin dielectric layer, LaA1O[sub 3], followed by a cap layer of a normal metal where the cap layer is formed by first depositing a thin layer of titanium (Ti) followed by a layer of gold (Au). The dielectric layer and the normal metal cap are patterned to the desired geometry. 8 figs.

  8. High temperature superconductor step-edge Josephson junctions using Ti-Ca-Ba-Cu-O

    SciTech Connect (OSTI)

    Ginley, David S. (Evergreen, CO); Hietala, Vincent M. (Placitas, NM); Hohenwarter, Gert K. G. (Madison, WI); Martens, Jon S. (Sunnyvale, CA); Plut, Thomas A. (Albuquerque, NM); Tigges, Chris P. (Albuquerque, NM); Vawter, Gregory A. (Albuquerque, NM); Zipperian, Thomas E. (Albuquerque, NM)

    1994-10-25T23:59:59.000Z

    A process for formulating non-hysteretic and hysteretic Josephson junctions using HTS materials which results in junctions having the ability to operate at high temperatures while maintaining high uniformity and quality. The non-hysteretic Josephson junction is formed by step-etching a LaAlO.sub.3 crystal substrate and then depositing a thin film of TlCaBaCuO on the substrate, covering the step, and forming a grain boundary at the step and a subsequent Josephson junction. Once the non-hysteretic junction is formed the next step to form the hysteretic Josephson junction is to add capacitance to the system. In the current embodiment, this is accomplished by adding a thin dielectric layer, LaA1O.sub.3, followed by a cap layer of a normal metal where the cap layer is formed by first depositing a thin layer of titanium (Ti) followed by a layer of gold (Au). The dielectric layer and the normal metal cap are patterned to the desired geometry.

  9. A Microscopic Examination of the Josephson Junction

    E-Print Network [OSTI]

    Freericks, Jim

    A Microscopic Examination of the Josephson Junction J. K. Freericks, P. Miller, and M. Jarrell Review, 1999 #12;Introduction · The Josephson-Junction Computer · Maximize · Resistively Shunted Junction

  10. Macroscopic quantum tunneling in Josephson junctions -

    E-Print Network [OSTI]

    Gross, Rudolf

    Macroscopic quantum tunneling in Josephson junctions - a method to characterise a well-shielded low Theory 5 1. The classical theory of Josephson junctions . . . . . . . . . . . . . . . . . 9 1-Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2. Josephson junction dynamics . . . . . . . . . . . . . . . . . . . . . . . . 15 2.1 The basics

  11. Semiconductor device PN junction fabrication using optical processing of amorphous semiconductor material

    DOE Patents [OSTI]

    Sopori, Bhushan; Rangappan, Anikara

    2014-11-25T23:59:59.000Z

    Systems and methods for semiconductor device PN junction fabrication are provided. In one embodiment, a method for fabricating an electrical device having a P-N junction comprises: depositing a layer of amorphous semiconductor material onto a crystalline semiconductor base, wherein the crystalline semiconductor base comprises a crystalline phase of a same semiconductor as the amorphous layer; and growing the layer of amorphous semiconductor material into a layer of crystalline semiconductor material that is epitaxially matched to the lattice structure of the crystalline semiconductor base by applying an optical energy that penetrates at least the amorphous semiconductor material.

  12. Josephson Junction Arrays with Bose-Einstein Condensates

    E-Print Network [OSTI]

    F. S. Cataliotti; S. Burger; C. Fort; P. Maddaloni; F. Minardi; A. Trombettoni; A. Smerzi; M. Inguscio

    2001-08-07T23:59:59.000Z

    We report on the direct observation of an oscillating atomic current in a one-dimensional array of Josephson junctions realized with an atomic Bose-Einstein condensate. The array is created by a laser standing-wave, with the condensates trapped in the valleys of the periodic potential and weakly coupled by the inter-well barriers. The coherence of multiple tunneling between adjacent wells is continuously probed by atomic interference. The square of the small-amplitude oscillation frequency is proportional to the microscopic tunneling rate of each condensate through the barriers, and provides a direct measurement of the Josephson critical current as a function of the intermediate barrier heights. Our superfluid array may allow investigation of phenomena so far inaccessible to superconducting Josephson junctions and lays a bridge between the condensate dynamics and the physics of discrete nonlinear media.

  13. Nanobonding for Multi-Junction Solar Cells at Room Temperature T. Yu, M. M. R. Howlader*, F. Zhang, M. Bakr

    E-Print Network [OSTI]

    Howlader, Matiar R

    -junction solar cell structure [GaInP/GaAs/InGaAsP/InGaAs] has been proposed, the epitaxially grown GaInP/GaAs junction on Ge layer bonded with oxidized Si substrate and the epitaxially grown InGaAsP/InGaAs junction interest. They are known for their high efficiency, which is achieved by dividing the absorption of light

  14. PHYSICAL REVIEW B 85, 214522 (2012) Area-dependence of spin-triplet supercurrent in ferromagnetic Josephson junctions

    E-Print Network [OSTI]

    Birge, Norman

    PHYSICAL REVIEW B 85, 214522 (2012) Area-dependence of spin-triplet supercurrent in ferromagnetic June 2012) Josephson junctions containing multiple ferromagnetic layers can carry spin-triplet Josephson junctions Yixing Wang, W. P. Pratt Jr., and Norman O. Birge* Department of Physics and Astronomy

  15. Measurements and Predictions of the Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Exchangers

    E-Print Network [OSTI]

    Thole, Karen A.

    Measurements and Predictions of the Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Exchangers Abstract The dominant thermal resistance used to increase heat transfer by initiating new boundary layer growth and increasing surface area

  16. Role of magnetic anisotropy in spin-filter junctions

    SciTech Connect (OSTI)

    Chopdekar, R.V.; Wong, F.; Nelson-Cheeseman, B.B.; Liberati, M.; Arenholz, E.; Suzuki, Y.

    2011-01-10T23:59:59.000Z

    We have fabricated oxide-based spin-filter junctions in which we demonstrate that magnetic anisotropy can be used to tune the transport behavior of spin-filter junctions. We have demonstrated spin-filtering behavior in La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/CoCr{sub 2}O{sub 4}/Fe{sub 3}O{sub 4} and La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/MnCr{sub 2}O{sub 4}/Fe{sub 3}O{sub 4} junctions where the interface anisotropy plays a significant role in determining transport behavior. Detailed studies of chemical and magnetic structure at the interfaces indicate that abrupt changes in magnetic anisotropy across the nonisostructural interface is the cause of the significant suppression of junction magnetoresistance in junctions with MnCr{sub 2}O{sub 4} barrier layers.

  17. Josephson junction Q-spoiler

    DOE Patents [OSTI]

    Clarke, John (Berkeley, CA); Hilbert, Claude (Austin, TX); Hahn, Erwin L. (Berkeley, CA); Sleator, Tycho (Berkeley, CA)

    1988-01-01T23:59:59.000Z

    An automatic Q-spoiler comprising at least one Josephson tunnel junction connected in an LC circuit for flow of resonant current therethrough. When in use in a system for detecting the magnetic resonance of a gyromagnetic particle system, a high energy pulse of high frequency energy irradiating the particle system will cause the critical current through the Josephson tunnel junctions to be exceeded, causing the tunnel junctions to act as resistors and thereby damp the ringing of the high-Q detection circuit after the pulse. When the current has damped to below the critical current, the Josephson tunnel junctions revert to their zero-resistance state, restoring the Q of the detection circuit and enabling the low energy magnetic resonance signals to be detected.

  18. Josephson junction Q-spoiler

    DOE Patents [OSTI]

    Clarke, J.; Hilbert, C.; Hahn, E.L.; Sleator, T.

    1986-03-25T23:59:59.000Z

    An automatic Q-spoiler comprising at least one Josephson tunnel junction connected in an LC circuit for flow of resonant current therethrough. When in use in a system for detecting the magnetic resonance of a gyromagnetic particle system, a high energy pulse of high frequency energy irradiating the particle system will cause the critical current through the Josephson tunnel junctions to be exceeded, causing the tunnel junctions to act as resistors and thereby damp the ringing of the high-Q detection circuit after the pulse. When the current has damped to below the critical current, the Josephson tunnel junctions revert to their zero-resistance state, restoring the Q of the detection circuit and enabling the low energy magnetic resonance signals to be detected.

  19. Understanding Complex Network Attack Graphs through Clustered Adjacency Matrices

    E-Print Network [OSTI]

    Noel, Steven

    Understanding Complex Network Attack Graphs through Clustered Adjacency Matrices Steven Noel}@gmu.edu Abstract We apply adjacency matrix clustering to network attack graphs for attack correlation, prediction, and hypothesizing. We self-multiply the clustered adjacency matrices to show attacker reachability across

  20. Seismicity in Azerbaijan and Adjacent Caspian Sea

    SciTech Connect (OSTI)

    Panahi, Behrouz M. [Geology Institute, Azerbaijan National Academy of Sciences, 29-A H. Javid Ave., Baku 1143 (Azerbaijan)

    2006-03-23T23:59:59.000Z

    So far no general view on the geodynamic evolution of the Black Sea to the Caspian Sea region is elaborated. This is associated with the geological and structural complexities of the region revealed by geophysical, geochemical, petrologic, structural, and other studies. A clash of opinions on geodynamic conditions of the Caucasus region, sometimes mutually exclusive, can be explained by a simplified interpretation of the seismic data. In this paper I analyze available data on earthquake occurrences in Azerbaijan and the adjacent Caspian Sea region. The results of the analysis of macroseismic and instrumental data, seismic regime, and earthquake reoccurrence indicate that a level of seismicity in the region is moderate, and seismic event are concentrated in the shallow part of the lithosphere. Seismicity is mostly intra-plate, and spatial distribution of earthquake epicenters does not correlate with the plate boundaries.

  1. Electromagnetically Induced Transparency in a Double Well Atomic Josephson Junction

    E-Print Network [OSTI]

    Weatherall, J. O.; Search, C. P.

    2009-01-01T23:59:59.000Z

    observation of these Josephson junction resonances. 2.dressed Bose condensed Josephson junction Let us consider ain a Double Well Atomic Josephson Junction J.O. Weatherall

  2. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells: Preprint

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-07-01T23:59:59.000Z

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n++ Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  3. Hybrid window layer for photovoltaic cells

    DOE Patents [OSTI]

    Deng, Xunming (Syvania, OH); Liao, Xianbo (Toledo, OH); Du, Wenhui (Toledo, OH)

    2011-10-04T23:59:59.000Z

    A novel photovoltaic solar cell and method of making the same are disclosed. The solar cell includes: at least one absorber layer which could either be a lightly doped layer or an undoped layer, and at least a doped window-layers which comprise at least two sub-window-layers. The first sub-window-layer, which is next to the absorber-layer, is deposited to form desirable junction with the absorber-layer. The second sub-window-layer, which is next to the first sub-window-layer, but not in direct contact with the absorber-layer, is deposited in order to have transmission higher than the first-sub-window-layer.

  4. Hybrid window layer for photovoltaic cells

    DOE Patents [OSTI]

    Deng, Xunming (Syvania, OH)

    2010-02-23T23:59:59.000Z

    A novel photovoltaic solar cell and method of making the same are disclosed. The solar cell includes: at least one absorber layer which could either be a lightly doped layer or an undoped layer, and at least a doped window-layers which comprise at least two sub-window-layers. The first sub-window-layer, which is next to the absorber-layer, is deposited to form desirable junction with the absorber-layer. The second sub-window-layer, which is next to the first sub-window-layer, but not in direct contact with the absorber-layer, is deposited in order to have transmission higher than the first-sub-window-layer.

  5. Hybrid window layer for photovoltaic cells

    DOE Patents [OSTI]

    Deng, Xunming (Sylvania, OH); Liao, Xianbo (Toledo, OH); Du, Wenhui (Toledo, OH)

    2011-02-01T23:59:59.000Z

    A novel photovoltaic solar cell and method of making the same are disclosed. The solar cell includes: at least one absorber layer which could either be a lightly doped layer or an undoped layer, and at least a doped window-layers which comprise at least two sub-window-layers. The first sub-window-layer, which is next to the absorber-layer, is deposited to form desirable junction with the absorber-layer. The second sub-window-layer, which is next to the first sub-window-layer, but not in direct contact with the absorber-layer, is deposited in order to have transmission higher than the first-sub-window-layer.

  6. Alexey Ustinov Two-level fluctuators in Josephson junctions Josephson junction as a tool to

    E-Print Network [OSTI]

    Fominov, Yakov

    Alexey Ustinov Two-level fluctuators in Josephson junctions Josephson junction as a tool;Alexey Ustinov Two-level fluctuators in Josephson junctions Outline JJ phase qubit Microwave spectroscopy. Ustinov. ArXiv:0909.3425 #12;Alexey Ustinov Two-level fluctuators in Josephson junctions Josephson tunnel

  7. Precision measurement with an optical Josephson junction

    E-Print Network [OSTI]

    H. T. Ng; K. Burnett; J. A. Dunningham

    2006-11-18T23:59:59.000Z

    We study a new type of Josephson device, the so-called "optical Josephson junction" as proposed in Phys. Rev. Lett. {\\bf 95}, 170402 (2005). Two condensates are optically coupled through a waveguide by a pair of Bragg beams. This optical Josephson junction is analogous to the usual Josephson junction of two condensates weakly coupled via tunneling. We discuss the use of this optical Josephson junction, for making precision measurements.

  8. Precision measurement with an optical Josephson junction

    SciTech Connect (OSTI)

    Ng, H. T.; Burnett, K. [Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Dunningham, J. A. [School of Physics and Astronomy, University of Leeds, LS2 9JT (United Kingdom)

    2007-06-15T23:59:59.000Z

    We present a theoretical study of a type of Josephson device, the so-called 'optical Josephson junction' [Y. Shin et al. Phys. Rev. Lett. 95, 170402 (2005).]. In this device, two condensates are optically coupled through a waveguide by a pair of Bragg beams. This optical Josephson junction differs from the usual Josephson junction where condensates are weakly coupled by tunneling through a barrier. We discuss the use of this optical Josephson junction, for making precision measurements.

  9. Dynamics of Josephson-junction ladders

    SciTech Connect (OSTI)

    Kim, J. (Department of Physics, Basic Science Research Institute, Pohang Institute of Science and Technology, Pohang P.O. Box 125, Kyungbuk 790-600 (Korea, Republic of) Division of Basic Science Research, Research Institute of Industrial Science and Technology, Pohang P.O. Box 135, Kyungbuk 790-600 (Korea, Republic of)); Choe, W.G.; Kim, S. (Department of Physics, Basic Science Research Institute, Pohang Institute of Science and Technology, Pohang P.O. Box 125, Kyungbuk 790-600 (Korea, Republic of)); Lee, H.J. (Department of Physics, Basic Science Research Institute, Pohang Institute of Science and Technology, Pohang P.O. Box 125, Kyungbuk 790-600 (Korea, Republic of) Division of Basic Science Research, Research Institute of Industrial Science and Technology, Pohang P.O. Box 135, Kyungbuk 790-600 (Korea, Republic of))

    1994-01-01T23:59:59.000Z

    We have numerically studied dynamical behaviors of Josephson-junction ladders consisting of [ital N][sub [ital p

  10. Thermal spin-transfer torque in magnetic tunnel junctions (invited)

    SciTech Connect (OSTI)

    Heiliger, Christian, E-mail: christian.heiliger@physik.uni-giessen.de; Franz, C.; Czerner, Michael [I. Physikalisches Institut, Justus Liebig University, Giessen (Germany)

    2014-05-07T23:59:59.000Z

    The thermal spin-transfer torque (TSTT) is an effect to switch the magnetic free layer in a magnetic tunnel junction by a temperature gradient only. We present ab initio calculations of the TSTT. In particular, we discuss the influence of magnetic layer composition by considering Fe{sub x}Co{sub 1–x} alloys. Further, we compare the TSTT to the bias voltage driven STT and discuss the requirements for a possible thermal switching. For example, only for very thin barriers of 3 monolayers MgO, a thermal switching is imaginable. However, even for such a thin barrier, the TSTT is still too small for switching at the moment and further optimization is needed. In particular, the TSTT strongly depends on the composition of the ferromagnetic layer. In our current study, it turns out that at the chosen thickness of the ferromagnetic layer, pure Fe gives the highest thermal spin-transfer torque.

  11. Quantum effects in nanoscale Josephson junction circuits

    E-Print Network [OSTI]

    Haviland, David

    Quantum effects in nanoscale Josephson junction circuits SILVIA CORLEVI Doctoral Thesis Stockholm Josephson junction arrays with SQUID geometry. TRITA FYS 2006:31 ISSN 0280-316X ISRN KTH/FYS/­06:31­SE ISBN study on single-charge effects in nanoscale Josephson junctions and Cooper pair transistors (CPTs

  12. Photovoltaic Cell Having A P-Type Polycrystalline Layer With Large Crystals

    DOE Patents [OSTI]

    Albright, Scot P. (Lakewood, CO); Chamberlin, Rhodes R. (El Paso, TX)

    1996-03-26T23:59:59.000Z

    A photovoltaic cell has an n-type polycrystalline layer and a p-type polycrystalline layer adjoining the n-type polycrystalline layer to form a photovoltaic junction. The p-type polycrystalline layer comprises a substantially planar layer portion having relatively large crystals adjoining the n-type polycrystalline layer. The planar layer portion includes oxidized impurities which contribute to obtainment of p-type electrical properties in the planar layer portion.

  13. Irreversible Electroporation Adjacent to the Rectum: Evaluation of Pathological Effects in a Pig Model

    SciTech Connect (OSTI)

    Schoellnast, Helmut [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States)] [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States); Monette, Sebastien [Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, Rockefeller University, Laboratory of Comparative Pathology (United States)] [Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, Rockefeller University, Laboratory of Comparative Pathology (United States); Ezell, Paula C. [Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, Rockefeller University, Research Animal Resource Center (United States)] [Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, Rockefeller University, Research Animal Resource Center (United States); Single, Gordon [AngioDynamics Inc. (United States)] [AngioDynamics Inc. (United States); Maybody, Majid [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States)] [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States); Weiser, Martin R.; Fong Yuman [Memorial Sloan-Kettering Cancer Center, Department of Surgery (United States)] [Memorial Sloan-Kettering Cancer Center, Department of Surgery (United States); Solomon, Stephen B., E-mail: solomons@mskcc.org [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States)

    2013-02-15T23:59:59.000Z

    To evaluate the effects of irreversible electroporation (IRE) on the rectum wall after IRE applied adjacent to the rectum. CT-guided IRE adjacent to the rectum wall was performed in 11 pigs; a total of 44 lesions were created. In five pigs, ablations were performed without a water-filled endorectal coil (group A); in six pigs, ablation was performed with the coil to avoid displacement of the rectum wall (group B). The pigs were killed after 7-15 days and the rectums were harvested for pathological evaluation. There was no evidence of perforation on gross postmortem examination. Perirectal muscle lesions were observed in 18 of 20 ablations in group A and in 21 of 24 ablations in group B. Inflammation and fibrosis of the muscularis propria was observed in ten of 18 lesions in group A and in ten of 21 lesions in group B. In group A, findings were limited to the external layer of the muscularis propria except for one lesion; in group B, findings were transmural in all cases. Transmural necrosis with marked suppurative mucosal inflammation was observed in seven of 21 lesions in group B and in no lesion in group A. IRE-ablation adjacent to the rectum may be uneventful if the rectum wall is mobile and able to contract. IRE-ablation of the rectum may be harmful if the rectum wall is fixed adjacent to the IRE-probe.

  14. Josephson-junction logic device

    SciTech Connect (OSTI)

    Suzuki, H.

    1987-12-01T23:59:59.000Z

    A Josephson-junction logic device having inductances and forming and AND circuit is described comprising: at least two superconductive loops, each having at least two Josephson-junction elements and a loop inductance connected between each of at least two Josephson-junction elements; at least two logic input signal lines, operatively connected to receive input currents, for supplying logic input signals; a bias line, operatively connected to at least two super conductive loops, for supplying a bias current to at least two superconductive loops, the bias current satisfying the condition vertical bar I/sub ml/ vertical bar > vertical bar I/sub mo/ vertical bar, where I/sub ml/ is a first threshold current, for switching the AND circuit, determined when at least two logic input signal lines receive different magnitude input currents and where I/sub mo/ is a second threshold current for switching the AND circuit, determined when at least two logic input signal lines receive the same magnitude input currents; and output terminals, operatively connected to one of at least two Josephson-junction elements, for outputting a logic output signal as a result of a logic operation performed on the logic input signals, whereby an operating margin of the AND circuit is expanded.

  15. Dilute Group III-V nitride intermediate band solar cells with contact blocking layers

    DOE Patents [OSTI]

    Walukiewicz, Wladyslaw (Kensington, CA); Yu, Kin Man (Lafayette, CA)

    2012-07-31T23:59:59.000Z

    An intermediate band solar cell (IBSC) is provided including a p-n junction based on dilute III-V nitride materials and a pair of contact blocking layers positioned on opposite surfaces of the p-n junction for electrically isolating the intermediate band of the p-n junction by blocking the charge transport in the intermediate band without affecting the electron and hole collection efficiency of the p-n junction, thereby increasing open circuit voltage (V.sub.OC) of the IBSC and increasing the photocurrent by utilizing the intermediate band to absorb photons with energy below the band gap of the absorber layers of the IBSC. Hence, the overall power conversion efficiency of a IBSC will be much higher than an conventional single junction solar cell. The p-n junction absorber layers of the IBSC may further have compositionally graded nitrogen concentrations to provide an electric field for more efficient charge collection.

  16. High thermal conductivity lossy dielectric using a multi layer configuration

    DOE Patents [OSTI]

    Tiegs, Terry N. (Lenoir City, TN); Kiggans, Jr., James O. (Oak Ridge, TN)

    2003-01-01T23:59:59.000Z

    Systems and methods are described for loss dielectrics. A loss dielectric includes at least one high dielectric loss layer and at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. A method of manufacturing a loss dielectric includes providing at least one high dielectric loss layer and providing at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. The systems and methods provide advantages because the loss dielectrics are less costly and more environmentally friendly than the available alternatives.

  17. Towards understanding junction degradation in cadmium telluride solar cells

    SciTech Connect (OSTI)

    Nardone, Marco, E-mail: marcon@bgsu.edu [Department of Environment and Sustainability, Bowling Green State University, Bowling Green, Ohio 43403 (United States)

    2014-06-21T23:59:59.000Z

    A degradation mechanism in cadmium telluride (CdTe/CdS) solar cells is investigated using time-dependent numerical modeling to simulate various temperature, bias, and illumination stress conditions. The physical mechanism is based on defect generation rates that are proportional to nonequilibrium charge carrier concentrations. It is found that a commonly observed degradation mode for CdTe/CdS solar cells can be reproduced only if defects are allowed to form in a narrow region of the absorber layer close to the CdTe/CdS junction. A key aspect of this junction degradation is that both mid-gap donor and shallow acceptor-type defects must be generated simultaneously in response to photo-excitation or applied bias. The numerical approach employed here can be extended to study other mechanisms for any photovoltaic technology.

  18. Organic light emitting device having multiple separate emissive layers

    DOE Patents [OSTI]

    Forrest, Stephen R. (Ann Arbor, MI)

    2012-03-27T23:59:59.000Z

    An organic light emitting device having multiple separate emissive layers is provided. Each emissive layer may define an exciton formation region, allowing exciton formation to occur across the entire emissive region. By aligning the energy levels of each emissive layer with the adjacent emissive layers, exciton formation in each layer may be improved. Devices incorporating multiple emissive layers with multiple exciton formation regions may exhibit improved performance, including internal quantum efficiencies of up to 100%.

  19. OBSERVATION OF ZERO POINT FLUCTUATIONS IN A RESISTIVELY SHUNTED JOSEPHSON TUNNEL JUNCTION

    E-Print Network [OSTI]

    Koch, Roger H.

    2012-01-01T23:59:59.000Z

    resistively shunted Josephson junctions in which quantumresistively shunted Josephson junction. For measurementresistively shunted Josephson junction in the quantum limit.

  20. Josephson junctions and dark energy

    E-Print Network [OSTI]

    Philippe Jetzer; Norbert Straumann

    2006-04-25T23:59:59.000Z

    In a recent paper Beck and Mackey [astro-ph/0603397] argue that the argument we gave in our paper [Phys. Lett. B 606, 77 (2005)] to disprove their claim that dark energy can be discovered in the Lab through noise measurements of Josephson junctions is incorrect. In particular, they emphasize that the measured noise spectrum in Josephson junctions is a consequence of the fluctuation dissipation theorem, while our argument was based on equilibrium statistical mechanics. In this note we show that the fluctuation dissipation relation does not depend upon any shift of vacuum (zero-point) energies, and therefore, as already concluded in our previous paper, dark energy has nothing to do with the proposed measurements.

  1. The Chern-Simons term in a dual Josephson junction

    E-Print Network [OSTI]

    L. S. Grigorio; M. S. Guimaraes; R. Rougemont; C. Wotzasek; C. A. D. Zarro

    2013-08-27T23:59:59.000Z

    A dual Josephson junction corresponding to a (2+1)-dimensional non-superconducting layer sandwiched between two (3+1)-dimensional dual superconducting regions constitutes a model of localization of a U(1) gauge field within the layer. Monopole tunneling currents flow from one dual superconducting region to another due to a phase difference between the wave functions of the monopole condensate below and above the non-superconducting layer when there is an electromagnetic field within the layer. These magnetic currents appear within the (2+1)-dimensional layer as a gas of magnetic instanton events and a weak electric charge confinement is expected to take place at very long distances within the layer. In the present work, we consider what happens when one introduces fermions in this physical scenario. Due to the dual Meissner effect featured in the dual superconducting bulk, it is argued that unconfined fermions would be localized within the (2+1)-dimensional layer, where their quantum fluctuations radiatively induce a Chern-Simons term, which is known to destroy the electric charge confinement and to promote the confinement of the magnetic instantons.

  2. Direct injection tunnel spectroscopy of a p-n junction Edward M. Likovich,1

    E-Print Network [OSTI]

    Russell, Kasey

    Direct injection tunnel spectroscopy of a p-n junction Edward M. Likovich,1 Kasey J. Russell,1,a tunnel injection of electrons. In contrast to the metal-base transistor design of conventional ballistic the semiconductor before they scatter and thermal- ize to the chemical potential of the base layer. For systems

  3. Atomic scale 0-pi transition in a high-Tc superconductor/ferromagnetic-insulator/high-T superconductor Josephson junction

    E-Print Network [OSTI]

    Kawabata, Shiro; Asano, Yasuhiro

    2011-01-01T23:59:59.000Z

    We study the Josephson transport in a high-Tc superconductor/ferromagnetic-insulator(FI)/high-Tc superconductor numerically. We found the formation of a pi-junction in such systems. More remarkably the ground state of such junction alternates between 0- and pi-states when thickness of FI is increasing by a single atomic layer. We propose an experimental setup for observing the atomic-scale 0-pi transition. Such FI-based pi-junctions can be used to implement highly-coherent quantum bits.

  4. adjacent pericarcinomatous foci: Topics by E-print Network

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

    many nets, those using them were doingwell. The schooner Sarah 350 Geological Setting, Mineral Resources and ancient works of Samos and adjacent islands of the Aegean Sea, 26-30...

  5. Bazaar [+] : addressing critical adjacencies in Mumbai's urban farm

    E-Print Network [OSTI]

    Bhat, Arjun (Arjun Devadas)

    2008-01-01T23:59:59.000Z

    This thesis focuses on the city of Mumbai, and evolves the notion of how "critical adjacency" has been instrumental in guiding the city's urban transformations into modernity. Presently, Mumbai experiences some of the ...

  6. Microwave photonics with Josephson junction arrays

    E-Print Network [OSTI]

    Zueco, David; Solano, Enrique; García-Ripoll, Juan José

    2011-01-01T23:59:59.000Z

    We introduce an architecture for a photonic crystal in the microwave regime based on superconducting transmission lines interrupted by Josephson junctions. A study of the scattering properties of a single junction in the line shows that the junction behaves as a perfect mirror when the photon frequency matches the Josephson plasma frequency. We generalize our calculations to periodic arrangements of junctions, demonstrating that they can be used for tunable band engineering, forming what we call a quantum circuit crystal. As a relevant application, we discuss the creation of stationary entanglement between two superconducting qubits interacting through a disordered media.

  7. Holographic p-wave Josephson junction

    E-Print Network [OSTI]

    Wang, Yong-Qiang; Zhao, Zhen-Hua

    2011-01-01T23:59:59.000Z

    In this work we generalized holographic model for s-wave DC Josephson junction constructed in arXiv:1101.3326[hep-th] to a holographic description for p-wave Josephson junction. By solving numerically the coupled equations of motion of Yang-Mills theory for a non-Abelian SU(2) gauge fields in (3+1)-dimensional AdS spacetimes, we shown that DC current of the p-wave Josephson junction is proportional to the sine of the phase difference across the junction like the s-wave case.

  8. Holographic p-wave Josephson junction

    E-Print Network [OSTI]

    Yong-Qiang Wang; Yu-Xiao Liu; Zhen-Hua Zhao

    2011-09-20T23:59:59.000Z

    In this work we generalized holographic model for s-wave DC Josephson junction constructed in arXiv:1101.3326[hep-th] to a holographic description for p-wave Josephson junction. By solving numerically the coupled equations of motion of Yang-Mills theory for a non-Abelian SU(2) gauge fields in (3+1)-dimensional AdS spacetimes, we shown that DC current of the p-wave Josephson junction is proportional to the sine of the phase difference across the junction like the s-wave case.

  9. The Chern-Simons term in a dual Josephson junction

    E-Print Network [OSTI]

    Grigorio, L S; Rougemont, R; Wotzasek, C; Zarro, C A D

    2013-01-01T23:59:59.000Z

    A dual Josephson junction corresponding to a (2+1)-dimensional non-superconducting layer sandwiched between two (3+1)-dimensional dual superconducting regions constitutes a model of localization of a U(1) gauge field within the layer. Monopole tunneling currents flow from one dual superconducting region to another due to a phase difference between the wave functions of the monopole condensate below and above the non-superconducting layer. These magnetic currents appear within the (2+1)-dimensional layer as a gas of magnetic instanton events and a weak electric charge confinement is expected to take place at very long distances within the layer. In the present work, we consider what happens when one introduces fermions in this physical scenario. Due to the dual Meissner effect featured in the dual superconducting bulk, it is argued that unconfined fermions would be localized within the (2+1)-dimensional layer, where their quantum fluctuations radiatively induce a Chern-Simons term, which is known to destroy th...

  10. Josephson junction between anisotropic superconductors Roman G. Mints

    E-Print Network [OSTI]

    Mints, Roman G.

    Josephson junction between anisotropic superconductors Roman G. Mints School of Physics 50011 Received 1 February 1999 Sin-Gordon equation for Josephson junctions with arbitrary misaligned, the contacts have Josephson properties. Hence, physical charac- teristics of Josephson junctions

  11. Superconducting Tunnel Junctions as Direct Detectors for Submillimeter Astronomy

    E-Print Network [OSTI]

    Superconducting Tunnel Junctions as Direct Detectors for Submillimeter Astronomy A Dissertation 2008 by John Daniel Teufel. All rights reserved. #12;Abstract Superconducting Tunnel Junctions on the of performance of superconducting tunnel junctions (STJ) as direct detectors for submillimeter radiation. Over

  12. Monolithic interconnected module with a tunnel junction for enhanced electrical and optical performance

    DOE Patents [OSTI]

    Murray, Christopher S. (Bethel Park, PA); Wilt, David M. (Bay Village, OH)

    2000-01-01T23:59:59.000Z

    An improved thermophotovoltaic (TPV) n/p/n device is provided. Monolithic Interconnected Modules (MIMS), semiconductor devices converting infrared radiation to electricity, have been developed with improved electrical and optical performance. The structure is an n-type emitter on a p-type base with an n-type lateral conduction layer. The incorporation of a tunnel junction and the reduction in the amount of p-type material used results in negligible parasitic absorption, decreased series resistance, increased voltage and increased active area. The novel use of a tunnel junction results in the potential for a TPV device with efficiency greater than 24%.

  13. Dark energy and Josephson junctions

    SciTech Connect (OSTI)

    Branchina, Vincenzo [Department of Physics, University of Catania, Via Santa Sofia 64, I-95123, Catania (Italy); Liberto, Marco Di; Lodato, Ivano, E-mail: vincenzo.branchina@ct.infn.it, E-mail: madiliberto@ssc.unict.it, E-mail: ivlodato@ssc.unict.it [Scuola Superiore di Catania, Via S. Nullo 5/i, Catania (Italy)

    2009-08-01T23:59:59.000Z

    It has been recently claimed that dark energy can be (and has been) observed in laboratory experiments by measuring the power spectrum S{sub I}(?) of the noise current in a resistively shunted Josephson junction and that in new dedicated experiments, which will soon test a higher frequency range, S{sub I}(?) should show a deviation from the linear rising observed in the lower frequency region because higher frequencies should not contribute to dark energy. Based on previous work on theoretical aspects of the fluctuation-dissipation theorem, we carefully investigate these issues and show that these claims are based on a misunderstanding of the physical origin of the spectral function S{sub I}(?). According to our analysis, dark energy has never been (and will never be) observed in Josephson junctions experiments. We also predict that no deviation from the linear rising behavior of S{sub I}(?) will be observed in forthcoming experiments. Our findings provide new (we believe definite) arguments which strongly support previous criticisms.

  14. Quantum Junction Solar Cells Jiang Tang,,

    E-Print Network [OSTI]

    Quantum Junction Solar Cells Jiang Tang,, Huan Liu,, David Zhitomirsky,§ Sjoerd Hoogland,§ Xihua, 1037 Luoyu Road, Wuhan, Hubei 430074, China § Department of Electrical and Computer Engineering-type and p-type materials to create the first quantum junction solar cells. We present a family

  15. Inelastic tunneling conductance and magnetoresistance investigations in dual ion-beam sputtered CoFeB(110)/MgO/CoFeB (110) magnetic tunnel junctions

    SciTech Connect (OSTI)

    Bhusan Singh, Braj; Chaudhary, Sujeet, E-mail: sujeetc@physics.iitd.ac.in [Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)

    2014-04-21T23:59:59.000Z

    Magnetic tunnel junctions (MTJs) comprising Ta(5)/NiFe(5)/IrMn(15)/CoFeB(5)/Mg(1)/MgO(3.5)/ CoFeB(5)/Ta(5)/Ag(20) (thickness in nm) with (110) oriented CoFeB layers are grown using dual ion beam sputtering. The tunnel magnetoresistance (TMR) of MTJs is found to be significantly bias dependent and exhibits zero bias anomaly (ZBA) which is attributed to the presence of magnetic impurities or diffusion of Mn from antiferromagnetic IrMn in the barrier. Adjacent to the ZBA, two peaks at 24?±?3?mV and 34?±?3?mV are also observed, which differ both in intensity as well as their position in the antiparallel and parallel magnetic states, suggesting that they are due to magnon excitations. In addition to this, a phonon peak at 65?±?3?mV is also observed. The effect of temperature on the inelastic and elastic tunneling contributions is studied in detail in 25–300?K range using the Glazman and Matveev model. Ten series of localized states are found to be involved in hopping conduction in the forbidden gap of MgO barrier. The effect of presence of such inelastic channels is found to be insignificant at low temperatures yielding sizeable enhancement in TMR.

  16. Gallium phosphide high-temperature bipolar junction transistor

    SciTech Connect (OSTI)

    Zipperian, T.E.; Dawson, L.R.; Caffin, R.J.

    1981-03-01T23:59:59.000Z

    Preliminary results are reported on the development of a high-temperature (> 350/sup 0/C) gallium phosphide bipolar junction transistor (BJT) for goethermal and other energy applications. This four-layer p/sup +/n/sup -/pp/sup +/ structure was fromed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The gallium phosphide BJT is observed to have a common-emitter current gain peaking in the range of 6 to 10 (for temperatures from 20/sup 0/C to 400/sup 0/C) and a room-temperature, punchthrough-limited, collector-emitter breakdown voltage of approximately -6V. Other parameters of interest include an f/sub/ = 400 KHz (at 20/sup 0/C) and a collector base leakage current = 200 ..mu..A (at 350/sup 0/C).

  17. Shapiro steps and stimulated radiation of electromagnetic waves due to Josephson oscillations in layered superconductors.

    SciTech Connect (OSTI)

    Bulaevskii, L. N.; Kosehlev, A. E.; Tachiki, M.; Materials Science Division; LANL; Univ. of Tokyo

    2008-01-01T23:59:59.000Z

    Single crystals of layered high-temperature superconductors intrinsically behave as stacks of Josephson junctions. We analyze response of current-biased stack of intrinsic junctions to irradiation by the external electromagnetic (em) wave. In addition to well-known Shapiro steps in the current-voltage characteristics, irradiation promotes stimulated radiation which adds with spontaneous Josephson radiation from the crystal. Such enhancement of radiation from current-biased crystal may be used for amplification of em waves. Irradiation also facilitates synchronization of Josephson oscillations in all intrinsic Josephson junctions of a single crystal as well as oscillations in intrinsic junctions of different crystals.

  18. OPTIMAL ALGORITHM FOR FINDING DNA MOTIFS WITH NUCLEOTIDE ADJACENT DEPENDENCY

    E-Print Network [OSTI]

    Chin, Francis Y.L.

    OPTIMAL ALGORITHM FOR FINDING DNA MOTIFS WITH NUCLEOTIDE ADJACENT DEPENDENCY FRANCIS Y.L. CHIN that the occurrence of a nucleotide in a binding site is independent of other nucleotides. More complicated representations, such as HMM or regular expression, exist that can capture the nucleotide dependency

  19. delta-biased Josephson tunnel junctions

    SciTech Connect (OSTI)

    Monaco, R.; Mygind, J.; Koshelets, V. P.; Dmitriev, P. [Istituto di Cibernetica del CNR, 80078 Pozzuoli (Italy) and Dipartimento di Fisica, Universita di Salerno, 84081 Baronissi (Italy); DTU Physics, Technical University of Denmark, B309, DK-2800 Lyngby (Denmark); Institute of Radio Engineering and Electronics, Russian Academy of Science, Mokhovaya 11, Bldg. 7, 125009 Moscow (Russian Federation)

    2010-02-01T23:59:59.000Z

    The behavior of a long Josephson tunnel junction drastically depends on the distribution of the dc bias current. We investigate the case in which the bias current is fed in the central point of a one-dimensional junction. Such junction configuration has been recently used to detect the persistent currents circulating in a superconducting loop. Analytical and numerical results indicate that the presence of fractional vortices leads to remarkable differences from the conventional case of uniformly distributed dc bias current. The theoretical findings are supported by detailed measurements on a number of delta-biased samples having different electrical and geometrical parameters.

  20. Tuning a short coherence length Josephson junction through a

    E-Print Network [OSTI]

    Freericks, Jim

    Tuning a short coherence length Josephson junction through a metal-insulator transition J. K University, Josephson Junction talk, 2001 #12;Josephson Tunnel Junctions · A Superconductor maintaining nonhysteretic behavior. J. K. Freericks, Georgetown University, Josephson Junction talk, 2001 S N

  1. THE USE OF SUPERCONDUCTING JUNCTIONS IN MAGNETOMETRY By J. CLARKE,

    E-Print Network [OSTI]

    Boyer, Edmond

    -8 gauss. In the second part, we discuss the properties of a type of Josephson junction in which] junctions in parallel. A Josephson junction consists of two superconductors separated by an insulating =|03C8|ei~, where 1 03C8|2 represents the density of condensed pairs. In a Josephson junction

  2. JOSEPHSON JUNCTION MIXER USING AN EXTERNAL LOCAL OSCILLATOR (*)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    255 JOSEPHSON JUNCTION MIXER USING AN EXTERNAL LOCAL OSCILLATOR (*) H. KANTER Electronic Research, studied the use of Josephson junctions as microwave mixers on the basis of the highly damped junction indicate that conversion as well as noise properties of Josephson junctions require more detailed studies

  3. Tunnel junction multiple wavelength light-emitting diodes

    DOE Patents [OSTI]

    Olson, J.M.; Kurtz, S.R.

    1992-11-24T23:59:59.000Z

    A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect. 5 figs.

  4. Tunnel junction multiple wavelength light-emitting diodes

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO)

    1992-01-01T23:59:59.000Z

    A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect.

  5. Self-consistent modeling of charge redistributions in Josephson junctions

    E-Print Network [OSTI]

    Freericks, Jim

    Self-consistent modeling of charge redistributions in Josephson junctions J. K. Freericks, Josephson Junction talk, 2000 #12;Josephson Proximity-Effect Junctions · A Superconductor-Normal metal, Georgetown University, Josephson Junction talk, 2000 S N S I I V V Ic #12;Andreev Bound States · At an N

  6. Superconductor-Correlated metal-Superconductor Josephson junctions

    E-Print Network [OSTI]

    Freericks, Jim

    Superconductor-Correlated metal- Superconductor Josephson junctions for high-speed digital. Freericks, Georgetown University, Josephson Junction talk, 2002 #12;Josephson Tunnel Junctions). J. K. Freericks, Georgetown University, Josephson Junction talk, 2002 S I S I I V V Ic #12

  7. Self-consistent modeling of SINIS and SNSNS Josephson junctions

    E-Print Network [OSTI]

    Freericks, Jim

    Self-consistent modeling of SINIS and SNSNS Josephson junctions J. K. Freericks Collaborators: Paul of Naval Research. J. K. Freericks, Georgetown University, Josephson Junction talk, 2000 #12;Josephson University, Josephson Junction talk, 2000 S I S I I V V Ic #12;Josephson Proximity-Effect Junctions

  8. Optoelectronic switching of addressable molecular crossbar junctions

    E-Print Network [OSTI]

    J. C. Li

    2006-11-22T23:59:59.000Z

    This letter reports on the observation of optoelectronic switching in addressable molecular crossbar junctions fabricated using polymer stamp-printing method. The active medium in the junction is a molecular self-assembled monolayer softly sandwiched between gold electrodes. The molecular junctions are investigated through currentvoltage measurements at varied temperature (from 95 to 300 K) in high vacuum condition. The junctions show reversible optoelectronic switching with the highest on/off ratio of 3 orders of magnitude at 95 K. The switching behavior is independent of both optical wavelength and molecular structure, while it strongly depends on the temperature. Initial analysis indicates that the distinct binding nature of the molecule/electrode interfaces play a dominant role in the switching performance.

  9. Quantum Coherence in a Superfluid Josephson Junction

    SciTech Connect (OSTI)

    Narayana, Supradeep; Sato, Yuki [Rowland Institute at Harvard, Harvard University, Cambridge, Massachusetts 02142 (United States)

    2011-02-04T23:59:59.000Z

    We report a new kind of experiment in which we take an array of nanoscale apertures that form a superfluid {sup 4}He Josephson junction and apply quantum phase gradients directly along the array. We observe collective coherent behaviors from aperture elements, leading to quantum interference. Connections to superconducting and Bose-Einstein condensate Josephson junctions as well as phase coherence among the superfluid aperture array are discussed.

  10. Method for closing a drift between adjacent in-situ oil shale retorts

    SciTech Connect (OSTI)

    Hines, A.E.

    1984-04-10T23:59:59.000Z

    A row of horizontally spaced-apart in situ oil shale retorts is formed in a subterranean formation containing oil shale. Each row of retorts is formed by excavating development drifts at different elevations through opposite side boundaries of a plurality of retorts in the row of retorts. Each retort is formed by explosively expanding formation toward one or more voids within the boundaries of the retort site to form a fragmented permeable mass of formation particles containing oil shale in each retort. Following formation of each retort, the retort development drifts on the advancing side of the retort are closed off by covering formation particles within the development drift with a layer of crushed oil shale particles having a particle size smaller than the average particle size of oil shale particles in the adjacent retort. In one embodiment, the crushed oil shale particles are pneumatically loaded into the development drift to pack the particles tightly all the way to the top of the drift and throughout the entire cross section of the drift. The closure between adjacent retorts provided by the finely divided oil shale provides sufficient resistance to gas flow through the development drift to effectively inhibit gas flow through the drift during subsequent retorting operations.

  11. Method for closing a drift between adjacent in situ oil shale retorts

    DOE Patents [OSTI]

    Hines, Alex E. (Grand Junction, CO)

    1984-01-01T23:59:59.000Z

    A row of horizontally spaced-apart in situ oil shale retorts is formed in a subterranean formation containing oil shale. Each row of retorts is formed by excavating development drifts at different elevations through opposite side boundaries of a plurality of retorts in the row of retorts. Each retort is formed by explosively expanding formation toward one or more voids within the boundaries of the retort site to form a fragmented permeable mass of formation particles containing oil shale in each retort. Following formation of each retort, the retort development drifts on the advancing side of the retort are closed off by covering formation particles within the development drift with a layer of crushed oil shale particles having a particle size smaller than the average particle size of oil shale particles in the adjacent retort. In one embodiment, the crushed oil shale particles are pneumatically loaded into the development drift to pack the particles tightly all the way to the top of the drift and throughout the entire cross section of the drift. The closure between adjacent retorts provided by the finely divided oil shale provides sufficient resistance to gas flow through the development drift to effectively inhibit gas flow through the drift during subsequent retorting operations.

  12. Electrical characteristics and interface structure of magnetic tunnel junctions with hafnium oxyfluoride barrier

    SciTech Connect (OSTI)

    Yu, Y.Y.; Kim, D.S.; Char, K. [Center for Strongly Correlated Materials Research and School of Physics, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2004-12-01T23:59:59.000Z

    We have studied the effects of fluorine inclusion on the electrical transport characteristics and interface structure of the hafnium oxide barrier in a magnetic tunnel junction. The tunneling magnetoresistance (TMR) and resistance-area (RA) as a function of oxidation time show that the TMR ratio of the hafnium oxyfluoride barrier is higher (8.3%) than that of the hafnium oxide barrier (5.7%) at their optimum conditions, and the oxyfluoride barrier junctions maintain a high TMR ratio even when the RA product increases by three orders of magnitude. X-ray photoelectron spectroscopy analysis shows that the fluorine atoms in the oxyfluoride barrier play an important role in the formation of a barrier with uniform composition. We believe that the initial fluoride layer is causing the subsequent oxygen diffusion to slow down, resulting in the formation of a defect-free hafnium oxide layer. These results are consistent with what we have found for aluminum oxyfluoride barriers.

  13. Investigation of TiO{sub x} barriers for their use in hybrid Josephson and tunneling junctions based on pnictide thin films

    SciTech Connect (OSTI)

    Döring, S., E-mail: sebastian.doering.1@uni-jena.de; Monecke, M.; Schmidt, S.; Schmidl, F.; Tympel, V.; Seidel, P., E-mail: paul.seidel@uni-jena.de [Institute of Solid State Physics, Friedrich-Schiller-Universität Jena, Helmholtzweg 5, 07743 Jena (Germany); Engelmann, J.; Kurth, F.; Iida, K.; Holzapfel, B. [Institute for Metallic Materials, IFW Dresden, Helmholtzstrasse 20, 01171 Dresden (Germany); Haindl, S. [Institute for Solid State Research, IFW Dresden, Helmholtzstrasse 20, 01171 Dresden (Germany); Mönch, I. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01171 Dresden (Germany)

    2014-02-28T23:59:59.000Z

    We tested oxidized titanium layers as barriers for hybrid Josephson junctions with high I{sub c}R{sub n}-products and for the preparation of junctions for tunneling spectroscopy. For that we firstly prepared junctions with conventional superconductor electrodes, such as lead and niobium, respectively. By tuning the barrier thickness, we were able to change the junction's behavior from a Josephson junction to tunnel-like behavior applicable for quasi-particle spectroscopy. Subsequently, we transferred the technology to junctions using Co-doped BaFe{sub 2}As{sub 2} thin films prepared by pulsed laser deposition as base electrode and evaporated Pb as counter electrode. For barriers with a thickness of 1.5?nm, we observe clear Josephson effects with I{sub c}R{sub n}?90??V at 4.2?K. These junctions behave SNS'-like (SNS: superconductor-normal conductor-superconductor) and are dominated by Andreev reflection transport mechanism. For junctions with barrier thickness of 2.0?nm and higher, no Josephson but SIS'- (SIS: superconductor-insulator-superconductor) or SINS'-like (SINS: superconductor-normal conductor-insulator-superconductor) behavior with a tunnel-like conductance spectrum was observed.

  14. Thermodynamic Signatures of Half-Quantum Vortices in p+ip Josephson Junction Arrays

    E-Print Network [OSTI]

    Krahn, Graham Joel

    2012-01-01T23:59:59.000Z

    bind a Majorana Fermion . . 3 Josephson Junction Arrays 3.14 p + ip Josephson Junction Arrays 4.1Bind a Majorana Fermion . . . . . . . . . Josephson Junction

  15. Temporal stability of Y Ba Cu O nano Josephson junctions from ion irradiation

    E-Print Network [OSTI]

    Cybart, Shane A.

    2014-01-01T23:59:59.000Z

    planar high temperature Josephson junctions fabricated usingYBa 2 Cu 3 O 7-? Josephson junctions via nanolithography andsuperconductor Josephson junctions,” J. Vac. Sci. Technol.

  16. E-Print Network 3.0 - addressable three-way junctions Sample...

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

    junctions can... Project Description: page 1 Project Description I. Introduction: Josephson junction networks Over... the past 25 years, superconducting Josephson junctions...

  17. Enhanced efficiency of graphene-silicon Schottky junction solar cells by doping with Au nanoparticles

    SciTech Connect (OSTI)

    Liu, X.; Zhang, X. W., E-mail: xwzhang@semi.ac.cn; Yin, Z. G.; Meng, J. H.; Gao, H. L.; Zhang, L. Q.; Zhao, Y. J.; Wang, H. L. [Key Lab of Semiconductor Materials Science, Institute of Semiconductors, CAS, Beijing 100083 (China)

    2014-11-03T23:59:59.000Z

    We have reported a method to enhance the performance of graphene-Si (Gr/Si) Schottky junction solar cells by introducing Au nanoparticles (NPs) onto the monolayer graphene and few-layer graphene. The electron transfer between Au NPs and graphene leads to the increased work function and enhanced electrical conductivity of graphene, resulting in a remarkable improvement of device efficiency. By optimizing the initial thickness of Au layers, the power conversion efficiency of Gr/Si solar cells can be increased by more than three times, with a maximum value of 7.34%. These results show a route for fabricating efficient and stable Gr/Si solar cells.

  18. Rapid and reversible reduction of junctional permeability in cells infected with a temperature-sensitive mutant of avian sarcoma virus

    E-Print Network [OSTI]

    Michael M. Atkinson; A. S. Menko; Ross G. Johnson; J R Sheppard; Judson D. Sheridan

    1981-01-01T23:59:59.000Z

    ABSTRACT The transformed or normal phenotype of cultured normal rat kidney cells infected with a temperature-sensitive mutant of avian sarcoma virus is conditional on the temperature at which the cells are grown. Using dye injection techniques, we show that junction-mediated dye transfer is also temperature-sensitive. The extent and rate of transfer between infected cells grown at the transformation-permissive temperature (35 ° C) is significantly reduced when compared to infected cells grown at the nonpermissive temperature (40.5 ° C) or uninfected cells grown at either temperature. Infected cells subjected to reciprocal temperature shifts express rapid and reversible alterations of dye transfer capacities, with responses evident by 15 min and completed by 60 min for temperature shifts in either direction. These results suggest that altered junctional capacities may be fundamental to the expression of the ASV-induced, transformed phenotype. Most cells possess permeable junctions which connect the interiors of adjacent cells and allow the direct exchange oflow molecular weight substances (for review, see references 1-3). When present, such junctions provide the capacity for direct electrical communication between electrically excitable cells

  19. Decoherence in a Josephson junction qubit

    E-Print Network [OSTI]

    A. J. Berkley; H. Xu; M. A. Gubrud; R. C. Ramos; J. R. Anderson; C. J. Lobb; F. C. Wellstood

    2003-03-01T23:59:59.000Z

    The zero-voltage state of a Josephson junction biased with constant current consists of a set of metastable quantum energy levels. We probe the spacings of these levels by using microwave spectroscopy to enhance the escape rate to the voltage state. The widths of the resonances give a measurement of the coherence time of the two states involved in the transitions. We observe a decoherence time shorter than that expected from dissipation alone in resonantly isolated 20 um x 5 um Al/AlOx/Al junctions at 60 mK. The data is well fit by a model including dephasing effects of both low-frequency current noise and the escape rate to the continuum voltage states. We discuss implications for quantum computation using current-biased Josephson junction qubits, including the minimum number of levels needed in the well to obtain an acceptable error limit per gate.

  20. Junction-side illuminated silicon detector arrays

    DOE Patents [OSTI]

    Iwanczyk, Jan S.; Patt, Bradley E.; Tull, Carolyn

    2004-03-30T23:59:59.000Z

    A junction-side illuminated detector array of pixelated detectors is constructed on a silicon wafer. A junction contact on the front-side may cover the whole detector array, and may be used as an entrance window for light, x-ray, gamma ray and/or other particles. The back-side has an array of individual ohmic contact pixels. Each of the ohmic contact pixels on the back-side may be surrounded by a grid or a ring of junction separation implants. Effective pixel size may be changed by separately biasing different sections of the grid. A scintillator may be coupled directly to the entrance window while readout electronics may be coupled directly to the ohmic contact pixels. The detector array may be used as a radiation hardened detector for high-energy physics research or as avalanche imaging arrays.

  1. Numerical Investigation of Josephson Junction Structures

    SciTech Connect (OSTI)

    Hristov, I.; Dimova, S.; Boyadjiev, T. [Faculty of Mathematics and Informatics, Sofia University 5 James Bourchier Blvd., 1164 Sofia (Bulgaria)

    2009-10-29T23:59:59.000Z

    Multilayered long Josephson Junction Structures form an interesting physical system where both nonlinearity and interaction between subsystems play an important role. Such systems allow to study physical effects that do not occur in single Josephson junction.The Sakai-Bodin-Pedersen model--a system of perturbed sine-Gordon equations--is used to study the dynamic states of stacks of inductively coupled long Josephson Junctions (LJJs). The corresponding static problem is numerically investigated as well. In order to study the stability of possible static solutions a Sturm-Liouville problem is generated and solved.The transitions from static to dynamic state and the scenario of these transitions are analyzed depending on the model parameters. Different physical characteristics--current-voltage characteristics, individual instant voltages and internal magnetic fields, are calculated and interpreted.

  2. Dynamical properties of high-temperature-superconductor granular bridge junctions: Inhomogeneous Josephson-junction-array model

    SciTech Connect (OSTI)

    Lee, J.; Lee, S.; Yu, J.; Park, G. [Department of Physics, Sogang University, Seoul 121-742 (Korea)] [Department of Physics, Sogang University, Seoul 121-742 (Korea)

    1996-02-01T23:59:59.000Z

    As an attempt to understand the dynamical behavior of the high-temperature-superconductor (HTSC) granular bridge junction, we model the granular HTSC bridge junction consisting of many small grains inside by an inhomogeneous Josephson junction array, i.e., randomly arranged Josephson junction arrays (JJA). To describe randomly distributed critical currents between the grains inside the HTSC granular bridge junction, we chose various possible configurations in {l_brace}{ital I}{sub {ital ij}}{sup {ital c}}{r_brace} and {l_brace}{ital R}{sub {ital ij}}{r_brace} for the one-dimensional (1D) and 2D inhomogeneous Josephson junctions, and calculated the current-voltage ({ital IV}) characteristics and self-radiation spectral densities of the 1D and 2D inhomogeneous Josephson junctions. As a result, depending upon the distribution of critical currents and shunted resistances, it is found that there are large variations of {ital IV} characteristics. In contrast to the appearance of giant Shapiro steps in the regular ordered array, such Shapiro steps disappear in the case of the disordered JJA due to the increased randomness in the distribution of critical currents. On the contrary, however, when there exists a correlation between critical currents and resistances, i.e., a constant Josephson voltage, {ital I}{sub {ital ij}}{sup {ital c}}{ital R}{sub {ital ij}}={ital V}{sub {ital J}} (constant), the fundamental Shapiro step emerges despite the disordered distribution of {ital I}{sub {ital ij}}{sup {ital c}}. The relevance of this model to the HTSC granular bridge junctions is discussed. In particular, experimentally observed dynamical behaviors of the HTSC granular bridge junctions are shown to be closely related to the case of the correlated distribution with constant Josephson voltage. {copyright} {ital 1996 The American Physical Society.}

  3. Axion physics in a Josephson junction environment

    E-Print Network [OSTI]

    Christian Beck

    2011-11-23T23:59:59.000Z

    We show that recent experiments based on Josephson junctions, SQUIDS, and coupled Josephson qubits have a cosmological interpretation in terms of axionic dark matter physics, in the sense that they allow for analogue simulation of early-universe axion physics. We propose new experimental setups in which SQUID-like axionic interactions in a resonant Josephson junction environment can be tested, similar in nature to recent experiments that test for quantum entanglement of two coupled Josephson qubits. We point out that the parameter values relevant for early-universe axion cosmology are accessible with present day's achievements in nanotechnology.

  4. Resonant electromagnetic emission from intrinsic Josephson-junction stacks with laterally modulated Josephson critical current.

    SciTech Connect (OSTI)

    Koshelev, A. E.; Bulaevskii, L. N.; Materials Science Division; LANL

    2008-01-01T23:59:59.000Z

    Intrinsic Josephson-junction stacks realized in mesas fabricated out of high-temperature superconductors may be used as sources of coherent electromagnetic radiation in the terahertz range. The major challenge is to synchronize Josephson oscillations in all junctions in the stack to get significant radiation out of the crystal edge parallel to the c axis. We suggest a simple way to solve this problem via artificially prepared lateral modulation of the Josephson critical current identical in all junctions. In such a stack, phase oscillations excite the in-phase Fiske mode when the Josephson frequency matches the Fiske-resonance frequency which is set by the stack lateral size. The powerful, almost standing electromagnetic wave is excited inside the crystal in the resonance. This wave is homogeneous across the layers, meaning that the oscillations are synchronized in all junctions in the stack. We evaluate behavior of the I-V characteristics and radiated power near the resonance for arbitrary modulation and find exact solutions for several special cases corresponding to symmetric and asymmetric modulations of the critical current.

  5. Phase Transition in Compact QED(3) and the Josephson Junction

    E-Print Network [OSTI]

    Vakif K. Onemli; Murat Tas; Bayram Tekin

    2001-08-22T23:59:59.000Z

    We study the finite temperature phase transition in 2+1 dimensional compact QED and its dual theory: Josephson junction. Duality of these theories at zero temperature was established long time ago by Hosotani. Phase transition in compact QED is well studied and we employ the `duality' to study the superconductivity phase transition in a Josephson junction. For a thick junction we obtain a critical temperature in terms of the geometrical properties of the junction.

  6. Holographic Josephson Junction in 3+1 dimensions

    E-Print Network [OSTI]

    Yong-Qiang Wang; Yu-Xiao Liu; Zhen-Hua Zhao

    2011-04-21T23:59:59.000Z

    In arXiv:1101.3326[hep-th], a (2+1)-dimensional holographic Josephson junction was constructed, and it was shown that the DC Josephson current is proportional to the sine of the phase difference across the junction. In this paper, we extend this study to a holographic description for the (3+1)-dimensional holographic DC Josephson junction. By solving numerically the coupled differential equations, we also obtain the familiar characteristics of Josephson junctions.

  7. Holographic Josephson Junction in 3+1 dimensions

    E-Print Network [OSTI]

    Wang, Yong-Qiang; Zhao, Zhen-Hua

    2011-01-01T23:59:59.000Z

    In arXiv:1101.3326[hep-th], a (2+1)-dimensional holographic Josephson junction was constructed, and it was shown that the DC Josephson current is proportional to the sine of the phase difference across the junction. In this paper, we extend this study to a holographic description for the (3+1)-dimensional holographic DC Josephson junction. By solving numerically the coupled differential equations, we also obtain the familiar characteristics of Josephson junctions.

  8. Corrosion protected, multi-layer fuel cell interface

    DOE Patents [OSTI]

    Feigenbaum, Haim (Ramat Ilan, IL); Pudick, Sheldon (Sayreville, NJ); Wang, Chiu L. (Edison, NJ)

    1986-01-01T23:59:59.000Z

    An improved interface configuration for use between adjacent elements of a fuel cell stack. The interface is impervious to gas and liquid and provides resistance to corrosion by the electrolyte of the fuel cell. The multi-layer configuration for the interface comprises a non-cupreous metal-coated metallic element to which is film-bonded a conductive layer by hot pressing a resin therebetween. The multi-layer arrangement provides bridging electrical contact.

  9. Theory of Proximity Effect in Junctions with Unconventional Superconductors

    E-Print Network [OSTI]

    Fominov, Yakov

    Theory of Proximity Effect in Junctions with Unconventional Superconductors Relevance to odd)Singlet superconductor junctions ()Triplet superconductor junctions [PRB 70, 012507 (2004), PRB71 024506 spectroscopy of Unconventional superconductors Tunneling spectroscopy has phase sensitivity px- wave dx2 -y2

  10. SOME CHARACTERISTICS OF JOSEPHSON JUNCTIONS AS RADIATION DETECTORS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    125 SOME CHARACTERISTICS OF JOSEPHSON JUNCTIONS AS RADIATION DETECTORS Yu. Ya. DIVIN, F. Ya. NAD les microponts. Abstract. 2014 The V-I characteristic of Josephson junction with an external parallel admittance, the high frequency impedance and high frequency response of a Josephson junction to small

  11. PARAMETRIC EXCITATION OF PLASMA OSCILLATIONS IN JOSEPHSON JUNCTIONS

    E-Print Network [OSTI]

    Boyer, Edmond

    223 PARAMETRIC EXCITATION OF PLASMA OSCILLATIONS IN JOSEPHSON JUNCTIONS N. F. PEDERSEN, M. R'équation différentielle de Mathieu. Abstract. 2014 Experiments on a Josephson junction analog showed a parametric in Josephson junctions at finite voltages have been discussed earlier [1]-[4]. In this communication we report

  12. JOSEPHSON JUNCTION DETECTOR FOR ASTRONOMICAL APPLICATIONS B. T. ULRICH

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    111 JOSEPHSON JUNCTION DETECTOR FOR ASTRONOMICAL APPLICATIONS B. T. ULRICH Department of Astronomy at the NRAO 11 m telescope. The detector uses a point contact Josephson junction, with a niobium point against-band Josephson junction radiometer for the 1.0 to 1.6 mm spectral region, and have used it to make astronomical

  13. AN ELECTRONIC EQUIVALENT SCHEME OF A JOSEPHSON JUNCTION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AN ELECTRONIC EQUIVALENT SCHEME OF A JOSEPHSON JUNCTION C. K. BAK Physics Laboratory I. A lot of phenomena observed in Josephson junctions are easily identified in the « equi- valent circuit ~. The lock range Ji corresponds to the supercurrent in a Josephson junction. The loop gain A(co) can

  14. Josephson junction simulation of neurons Patrick Crotty,1

    E-Print Network [OSTI]

    Segall, Ken

    Josephson junction simulation of neurons Patrick Crotty,1 Dan Schult,2 and Ken Segall1 1 Physics of neurons, we present superconducting circuits containing Josephson junctions that model biologically technologies, large interconnected networks of Josephson junction neurons would operate fully in parallel

  15. Superconductor-Correlated metal-Superconductor Josephson junctions

    E-Print Network [OSTI]

    Freericks, Jim

    Superconductor-Correlated metal- Superconductor Josephson junctions for high-speed digital. Freericks, Georgetown University, Josephson Junction talk, 2002 #12;Digital Electronics and RSFQ logic, Georgetown University, Josephson Junction talk, 2002 X X Binary 0, no flux Binary 1, one flux quantum #12

  16. Localized mode interactions in 0-Josephson junctions Hadi Susanto1

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Localized mode interactions in 0- Josephson junctions Hadi Susanto1 and Gianne Derks2 1 School of Mathematics, University of Surrey, Guildford, Surrey, GU2 7XH, UK A long Josephson junction containing regions in the system, it is shown that Josephson junctions with phase-shift can be an ideal setting for studying

  17. Superconductor-Correlated metal-Superconductor Josephson junctions

    E-Print Network [OSTI]

    Freericks, Jim

    Superconductor-Correlated metal- Superconductor Josephson junctions for high-speed digital. Freericks, Georgetown University, Josephson Junction talk, 2003 #12;Digital Electronics and RSFQ logic, Georgetown University, Josephson Junction talk, 2003 X X Binary 0, no flux Binary 1, one flux quantum #12

  18. Multi-Scroll and Hypercube Attractors from Josephson Junctions

    E-Print Network [OSTI]

    Multi-Scroll and Hypercube Attractors from Josephson Junctions M¨us¸tak E. Yalc¸in Istanbul Leuven, Belgium Email: Johan.Suykens@esat.kuleuven.ac.be Abstract-- In this paper Josephson junctions of the Josephson junction in a general Jerk circuit in such a way that there is no need for synthesizing

  19. EA-0930: Facility Operations at the U.S. DOE Grand Junction Projects Office, Grand Junction, Colorado

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts of the proposal to expand and upgrade the U.S. Department of Energy's Grand Junction Projects Office facilities and operations in Grand Junction, Colorado.

  20. Topological Order in Frustrated Josephson Junction Arrays

    E-Print Network [OSTI]

    M. C. Diamantini; P. Sodano; C. A. Trugenberger

    2008-06-02T23:59:59.000Z

    We show that electrically and magnetically frustrated Josephson junction arrays (JJAs) realize topological order with a non-trivial ground state degeneracy on manifolds with non-trivial topology. The low-energy theory has the same gauge dynamics of the unfrustrated JJAs but for different, "fractional" degrees of freedom, a principle reminescent of Jain's composite electrons in the fractional quantum Hall effect.

  1. Superconducting Topological Fluids in Josephson Junction Arrays

    E-Print Network [OSTI]

    M. Cristina Diamantini; Pasquale Sodano; Carlo A. Trugenberger

    2006-04-21T23:59:59.000Z

    We argue that the frustrated Josephson junction arrays may support a topologically ordered superconducting ground state, characterized by a non-trivial ground state degeneracy on the torus. This superconducting quantum fluid provides an explicit example of a system in which superconductivity arises from a topological mechanism rather than from the usual Landau-Ginzburg mechanism.

  2. Gallium nitride junction field-effect transistor

    DOE Patents [OSTI]

    Zolper, John C. (Albuquerque, NM); Shul, Randy J. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    An all-ion implanted gallium-nitride (GaN) junction field-effect transistor (JFET) and method of making the same. Also disclosed are various ion implants, both n- and p-type, together with or without phosphorous co-implantation, in selected III-V semiconductor materials.

  3. Axion mass estimates from resonant Josephson junctions

    E-Print Network [OSTI]

    Beck, Christian

    2014-01-01T23:59:59.000Z

    Recently it has been proposed that dark matter axions from the galactic halo can produce a small Shapiro step-like signal in Josephson junctions whose Josephson frequency resonates with the axion mass [C. Beck, PRL 111, 231801 (2013)]. Here we show that the axion field equations in a voltage-driven Josephson junction environment allow for a nontrivial solution where the axion-induced electric current manifests itself as an oscillating supercurrent. The linear change of phase associated with this nontrivial solution implies the existence of a large magnetic field in a tiny surface area of the weak link region of the junction which makes incoming axions decay into microwave photons. We derive a condition for the design of Josephson junction experiments so that they can act as optimum axion detectors. Four independent recent experiments are discussed in this context. The observed Shapiro step anomalies of all four experiments consistently point towards an axion mass of $(110 \\pm 2)\\mu $eV. This mass value is com...

  4. Fast algorithms for triangular Josephson junction arrays

    SciTech Connect (OSTI)

    Datta, S.; Sahdev, D. [Indian Institute of Technology, Kanpur (India)] [Indian Institute of Technology, Kanpur (India)

    1997-04-01T23:59:59.000Z

    We develop fast algorithms for the numerical study of two-dimensional triangular Josephson junction arrays. The Dirac bra-ket formalism is introduced in the context of such arrays. We note that triangular arrays can have both hexagonal and rectangular periodicity and develop algorithms for each. Boundaries are next introduced and fast algorithms for finite arrays are developed. 40 refs., 4 figs.

  5. Measuring Vacuum Polarization with Josephson Junctions

    SciTech Connect (OSTI)

    Penin, Alexander A. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada) and Institute for Nuclear Research of Russian Academy of Sciences, 117312 Moscow (Russian Federation)

    2010-03-05T23:59:59.000Z

    We argue that the vacuum polarization by the virtual electron-positron pairs can be measured by studying a Josephson junction in a strong magnetic field. The vacuum polarization results in a weak dependence of the Josephson constant on the magnetic field strength which is within the reach of the existing experimental techniques.

  6. Axion mass estimates from resonant Josephson junctions

    E-Print Network [OSTI]

    Christian Beck

    2014-06-10T23:59:59.000Z

    Recently it has been proposed that dark matter axions from the galactic halo can produce a small Shapiro step-like signal in Josephson junctions whose Josephson frequency resonates with the axion mass [C. Beck, PRL 111, 231801 (2013)]. Here we show that the axion field equations in a voltage-driven Josephson junction environment allow for a nontrivial solution where the axion-induced electric current manifests itself as an oscillating supercurrent. The linear change of phase associated with this nontrivial solution implies the formal existence of a large magnetic field in a tiny surface area of the weak link region of the junction which makes incoming axions decay into microwave photons. We derive a condition for the design of Josephson junction experiments so that they can act as optimum axion detectors. Four independent recent experiments are discussed in this context. The observed Shapiro step anomalies of all four experiments consistently point towards an axion mass of $(110 \\pm 2)\\mu $eV. This mass value is compatible with the recent BICEP2 results and implies that Peccei-Quinn symmetry breaking was taking place after inflation.

  7. Adjacent-Channel Interference in Frequency-Hopping Ad Hoc Networks

    E-Print Network [OSTI]

    Valenti, Matthew C.

    Adjacent-Channel Interference in Frequency-Hopping Ad Hoc Networks M. C. Valenti 1 D. Torrieri 2 S, 2013 Salvatore Talarico (shortinst)Adjacent-Channel Interference in Frequency-Hopping Ad Hoc Networks June 11, 2013 1 / 23 #12;Outline 1 Frequency-Hopping Ad Hoc Networks 2 Outage Probability with Adjacent

  8. Electronic Transport in Few-layer Graphene

    E-Print Network [OSTI]

    Zhao, Zeng

    2013-01-01T23:59:59.000Z

    electrodes as Josephson Junction. Fifth, patterns, as largegraphene-based Josephson junction. Such a system has been

  9. Method of depositing multi-layer carbon-based coatings for field emission

    DOE Patents [OSTI]

    Sullivan, John P. (Albuquerque, NM); Friedmann, Thomas A. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    A novel field emitter device for cold cathode field emission applications, comprising a multi-layer resistive carbon film. The multi-layered film of the present invention is comprised of at least two layers of a resistive carbon material, preferably amorphous-tetrahedrally coordinated carbon, such that the resistivities of adjacent layers differ. For electron emission from the surface, the preferred structure comprises a top layer having a lower resistivity than the bottom layer. For edge emitting structures, the preferred structure of the film comprises a plurality of carbon layers, wherein adjacent layers have different resistivities. Through selection of deposition conditions, including the energy of the depositing carbon species, the presence or absence of certain elements such as H, N, inert gases or boron, carbon layers having desired resistivities can be produced. Field emitters made according the present invention display improved electron emission characteristics in comparison to conventional field emitter materials.

  10. Radiation due to Josephson oscillations in layered superconductors.

    SciTech Connect (OSTI)

    Bulaevskii, L. N.; Koshelev, A. E.; Materials Science Division; LANL

    2007-01-01T23:59:59.000Z

    We derive the power of direct radiation into free space induced by Josephson oscillations in intrinsic Josephson junctions of layered superconductors. We consider the superradiation regime for a crystal cut in the form of a thin slice parallel to the c axis. We find that the radiation correction to the current-voltage characteristic in this regime depends only on crystal shape. We show that at a large number of junctions oscillations are synchronized providing high radiation power and efficiency in the terahertz frequency range. We discuss the crystal parameters and bias current optimal for radiation power and crystal cooling.

  11. Dissipation and traversal time in Josephson junctions

    SciTech Connect (OSTI)

    Cacciari, Ilaria; Ranfagni, Anedio [Istituto di Fisica Applicata 'Nello Carrara' del Consiglio Nazionale delle Ricerche, via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze (Italy); Moretti, Paolo [Istituto dei Sistemi Complessi del Consiglio Nazionale delle Ricerche, Sezione di Firenze, via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze (Italy)

    2010-05-01T23:59:59.000Z

    The various ways of evaluating dissipative effects in macroscopic quantum tunneling are re-examined. The results obtained by using functional integration, while confirming those of previously given treatments, enable a comparison with available experimental results relative to Josephson junctions. A criterion based on the shortening of the semiclassical traversal time tau of the barrier with regard to dissipation can be established, according to which DELTAtau/tau > or approx. N/Q, where Q is the quality factor of the junction and N is a numerical constant of order unity. The best agreement with the experiments is obtained for N=1.11, as it results from a semiempirical analysis based on an increase in the potential barrier caused by dissipative effects.

  12. Screening current effects in Josephson junction arrays

    E-Print Network [OSTI]

    A. Petraglia; G. Filatrella; G. Rotoli

    1995-07-28T23:59:59.000Z

    The purpose of this work is to compare the dynamics of arrays of Josephson junctions in presence of magnetic field in two different frameworks: the so called XY frustrated model with no self inductance and an approach that takes into account the screening currents (considering self inductances only). We show that while for a range of parameters the simpler model is sufficiently accurate, in a region of the parameter space solutions arise that are not contained in the XY model equations.

  13. q-deformed dynamics and Josephson junction

    E-Print Network [OSTI]

    Ramandeep S. Johal

    2000-10-04T23:59:59.000Z

    We define a generalized rate equation for an observable in quantum mechanics, that involves a parameter q and whose limit $q\\to 1$ gives the standard Heisenberg equation. The generalized rate equation is used to study dynamics of current biased Josephson junction. It is observed that this toy model incorporates diffraction like effects in the critical current. Physical interpretation for q is provided which is also shown to be q-deformation parameter.

  14. Defect formation in long Josephson junctions

    SciTech Connect (OSTI)

    Gordeeva, Anna V. [Institute for Physics of Microstructures, RAS, GSP-105, Nizhny Novgorod 603950 (Russian Federation); Department of Physics, B309, Technical University of Denmark, DK-2800 Lyngby (Denmark); Pankratov, Andrey L. [Institute for Physics of Microstructures, RAS, GSP-105, Nizhny Novgorod 603950 (Russian Federation)

    2010-06-01T23:59:59.000Z

    We study numerically a mechanism of vortex formation in a long Josephson junction within the framework of the one-dimensional sine-Gordon model. This mechanism is switched on below the critical temperature. It is shown that the number of fluxons versus velocity of cooling roughly scales according to the power law with the exponent of either 0.25 or 0.5 depending on the temperature variation in the critical current density.

  15. Quantum dynamics in the bosonic Josephson junction

    SciTech Connect (OSTI)

    Chuchem, Maya; Cohen, Doron [Department of Physics, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105 (Israel); Smith-Mannschott, Katrina [Department of Physics, Wesleyan University, Middletown, Connecticut 06459 (United States); MPI for Dynamics and Self-Organization, Bunsenstrasse 10, D-37073 Goettingen (Germany); Hiller, Moritz [Physikalisches Institut, Albert-Ludwigs-Universitaet, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany); Kottos, Tsampikos [Department of Physics, Wesleyan University, Middletown, Connecticut 06459 (United States); Vardi, Amichay [Department of Chemistry, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105 (Israel); Institute for Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States)

    2010-11-15T23:59:59.000Z

    We employ a semiclassical picture to study dynamics in a bosonic Josephson junction with various initial conditions. Phase diffusion of coherent preparations in the Josephson regime is shown to depend on the initial relative phase between the two condensates. For initially incoherent condensates, we find a universal value for the buildup of coherence in the Josephson regime. In addition, we contrast two seemingly similar on-separatrix coherent preparations, finding striking differences in their convergence to classicality as the number of particles increases.

  16. Hydrocarbon provinces and productive trends in Libya and adjacent areas

    SciTech Connect (OSTI)

    Missallati, A.A. (Agip (N.A.M.E.)Ltd., Tripoli (Libya))

    1988-08-01T23:59:59.000Z

    According to the age of major reservoirs, hydrocarbon occurrences in Libya and adjacent areas can be grouped into six major systems which, according to their geographic locations, can be classified into two major hydrocarbon provinces: (1) Sirte-Pelagian basins province, with major reservoirs ranging from middle-late Mesozoic to early Tertiary, and (2) Murzog-Ghadames basins province, with major reservoirs ranging from early Paleozoic to early Mesozoic. In the Sirte-Pelagian basins province, hydrocarbons have been trapped in structural highs or in stratigraphic wedge-out against structural highs and in carbonate buildups. Here, hydrocarbon generation is characterized by the combined effect of abundant structural relief and reservoir development in the same hydrocarbon systems of the same age, providing an excellent example of hydrocarbon traps in sedimentary basins that have undergone extensive tensional fracturing in a shallow marine environment. In the Murzog-Ghadames basins province, hydrocarbons have been trapped mainly in structural highs controlled by paleostructural trends as basement arches which acted as focal points for oil migration and accumulation.

  17. Josephson junction in a thin film

    SciTech Connect (OSTI)

    Kogan, V. G.; Dobrovitski, V. V.; Clem, J. R.; Mawatari, Yasunori; Mints, R. G.

    2001-04-01T23:59:59.000Z

    The phase difference {phi}(y) for a vortex at a line Josephson junction in a thin film attenuates at large distances as a power law, unlike the case of a bulk junction where it approaches exponentially the constant values at infinities. The field of a Josephson vortex is a superposition of fields of standard Pearl vortices distributed along the junction with the line density {phi}'(y)/2{pi}. We study the integral equation for {phi}(y) and show that the phase is sensitive to the ratio l/{Lambda}, where l={lambda}{sub J}{sup 2}/{lambda}{sub L}, {Lambda}=2{lambda}{sub L}{sup 2}/d, {lambda}{sub L}, and {lambda}{sub J} are the London and Josephson penetration depths, and d is the film thickness. For l<<{Lambda}, the vortex ''core'' of the size l is nearly temperature independent, while the phase ''tail'' scales as l{Lambda}/y{sup 2}={lambda}{sub J}2{lambda}{sub L}/d/y{sup 2}; i.e., it diverges as T{yields}T{sub c}. For l>>{Lambda}, both the core and the tail have nearly the same characteristic length l{Lambda}.

  18. Photovoltaic Device Including A Boron Doping Profile In An I-Type Layer

    DOE Patents [OSTI]

    Yang, Liyou (Lawrenceville, NJ)

    1993-10-26T23:59:59.000Z

    A photovoltaic cell for use in a single junction or multijunction photovoltaic device, which includes a p-type layer of a semiconductor compound including silicon, an i-type layer of an amorphous semiconductor compound including silicon, and an n-type layer of a semiconductor compound including silicon formed on the i-type layer. The i-type layer including an undoped first sublayer formed on the p-type layer, and a boron-doped second sublayer formed on the first sublayer.

  19. Single P-N junction tandem photovoltaic device

    DOE Patents [OSTI]

    Walukiewicz, Wladyslaw (Kensington, CA); Ager, III, Joel W. (Berkeley, CA); Yu, Kin Man (Lafayette, CA)

    2011-10-18T23:59:59.000Z

    A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

  20. Single P-N junction tandem photovoltaic device

    DOE Patents [OSTI]

    Walukiewicz, Wladyslaw (Kensington, CA); Ager, III, Joel W. (Berkeley, CA); Yu, Kin Man (Lafayette, CA)

    2012-03-06T23:59:59.000Z

    A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

  1. Study of a-SiGe:H films and nip devices used in high efficiency triple junction solar cells

    E-Print Network [OSTI]

    Deng, Xunming

    Study of a-SiGe:H films and n­i­p devices used in high efficiency triple junction solar cells-Si:H films). This allows the capture of the full range of the solar spectra in different layers and thus, North Guwahati, Guwahati 781 039, India Abstract We report our systematic studies on a-SiGe:H thin films

  2. Pseudospherical Junctions or Josephson Effect, Backlund Transformations, and Fine Structure Coupling

    E-Print Network [OSTI]

    Binder, Bernd

    , that the geometric phase evolution within M circularly and toroidally arranged virtual Josephson junctions (coupled by a special arrangement of Josephson junctions. In this con- text "virtual junction" means simply a scalar impedance will represent in this paper a "virtual Josephson junction". The Josephson junctions

  3. Classical phase diffusion in small hysteretic Josephson junctions

    SciTech Connect (OSTI)

    Martinis, J.M.; Kautz, R.L. (National Institute of Standards and Technology, Boulder, Colorado 80303 (US))

    1989-10-02T23:59:59.000Z

    The existence of classical phase diffusion in hysteretic junctions is demonstrated by quantitative agreement between experimental and simulated {ital I}-{ital V} curves. The simulations are based on a circuit that accurately models both the junction and its external shunting impedance at microwave frequencies. We show that the bias current at which the junction switches from the phase diffusion state to the voltage state is sensitive to dissipation at microwave frequencies.

  4. E-Print Network 3.0 - adjacent continental margin Sample Search...

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

    adjacent to the margin. The lack of these features is also characteristic of modern transform margins... -early Paleozoic southern Lau- rentian continental ... Source: Huerta,...

  5. E-Print Network 3.0 - adjacent offshore area Sample Search Results

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

    offshore area Search Powered by Explorit Topic List Advanced Search Sample search results for: adjacent offshore area Page: << < 1 2 3 4 5 > >> 1 Travel Characteristics of Marine...

  6. E-Print Network 3.0 - adjacent natural forest Sample Search Results

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

    ... Source: Forest Research Agency of the UK Forestry Commission Collection: Renewable Energy 5 Ecology 2001 89, 325338 Summary: occurred directly adjacent to old-woods (forest...

  7. E-Print Network 3.0 - adjacent compression fractures Sample Search...

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

    and triangular columns formed by column-bounding fractures adjacent to inflation-fracture walls... the cooling rate, caus- ing increased fracturing ... Source: Kattenhorn,...

  8. E-Print Network 3.0 - adjacent marine waters Sample Search Results

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

    SEMINAR Diatom Based Quantitative Reconstructions of Summary: . The bay ecosystem is affected by changes in water quality and quantity in the adjacent marine... and freshwater...

  9. Organic-Inorganic Hetero Junction White Light Emitting Diode.

    E-Print Network [OSTI]

    Lubuna Beegum, Shafeek

    2008-01-01T23:59:59.000Z

    ?? The purpose of this thesis work is to design and fabricates organic-inorganic hetero junction White Light Emitting Diode (WLED). In this WLED, inorganic material… (more)

  10. Quantum manipulation and simulation using Josephson junction arrays

    E-Print Network [OSTI]

    Xingxiang Zhou; Ari Mizel

    2006-05-01T23:59:59.000Z

    We discuss the prospect of using quantum properties of large scale Josephson junction arrays for quantum manipulation and simulation. We study the collective vibrational quantum modes of a Josephson junction array and show that they provide a natural and practical method for realizing a high quality cavity for superconducting qubit based QED. We further demonstrate that by using Josephson junction arrays we can simulate a family of problems concerning spinless electron-phonon and electron-electron interactions. These protocols require no or few controls over the Josephson junction array and are thus relatively easy to realize given currently available technology.

  11. A Josephson Junction Microscope for Low-frequency Fluctuators

    E-Print Network [OSTI]

    L. Tian; R. W. Simmonds

    2007-05-10T23:59:59.000Z

    The high-Q harmonic oscillator mode of a Josephson junction can be used as a novel probe of spurious two-level systems (TLSs) inside the amorphous oxide tunnel barriers of the junction. In particular, we show that spectroscopic transmission measurements of the junction resonator mode can reveal how the coupling magnitude between the junction and the TLSs varies with an external magnetic field applied in the plane of the tunnel barrier. The proposed experiments offer the possibility of clearly resolving the underlying coupling mechanism for these spurious TLSs, an important decoherence source limiting the quality of superconducting quantum devices.

  12. Non-relativistic Josephson Junction from Holography

    E-Print Network [OSTI]

    Li, Huai-Fan; Wang, Yong-Qiang; Zhang, Hai-Qing

    2014-01-01T23:59:59.000Z

    We construct a Josephson junction in non-relativistic case with a Lifshitz geometry as the dual gravity. We investigate the effect of the Lifshitz scaling in comparison with its relativistic counterpart. The standard sinusoidal relation between the current and the phase difference is found for various Lifshitz scalings characterised by the dynamical critical exponent. We also find the exponential decreasing relation between the condensate of the scalar operator within the barrier at zero current and the width of the weak link, as well as the relation between the critical current and the width. Nevertheless, the coherence lengths obtained from two exponential decreasing relations generically have discrepancies for non-relativistic dual.

  13. Quantum dynamics in the bosonic Josephson junction

    E-Print Network [OSTI]

    Maya Chuchem; Katrina Smith-Mannschott; Moritz Hiller; Tsampikos Kottos; Amichay Vardi; Doron Cohen

    2010-10-21T23:59:59.000Z

    We employ a semiclassical picture to study dynamics in a bosonic Josephson junction with various initial conditions. Phase-diffusion of coherent preparations in the Josephson regime is shown to depend on the initial relative phase between the two condensates. For initially incoherent condensates, we find a universal value for the buildup of coherence in the Josephson regime. In addition, we contrast two seemingly similar on-separatrix coherent preparations, finding striking differences in their convergence to classicality as the number of particles increases.

  14. Non-relativistic Josephson Junction from Holography

    E-Print Network [OSTI]

    Huai-Fan Li; Li Li; Yong-Qiang Wang; Hai-Qing Zhang

    2014-12-09T23:59:59.000Z

    We construct a Josephson junction in non-relativistic case with a Lifshitz geometry as the dual gravity. We investigate the effect of the Lifshitz scaling in comparison with its relativistic counterpart. The standard sinusoidal relation between the current and the phase difference is found for various Lifshitz scalings characterised by the dynamical critical exponent. We also find the exponential decreasing relation between the condensate of the scalar operator within the barrier at zero current and the width of the weak link, as well as the relation between the critical current and the width. Nevertheless, the coherence lengths obtained from two exponential decreasing relations generically have discrepancies for non-relativistic dual.

  15. Quantum breathers in capacitively coupled Josephson junctions: Correlations, number conservation, and entanglement

    E-Print Network [OSTI]

    Flach, Sergej

    Quantum breathers in capacitively coupled Josephson junctions: Correlations, number conservation coupled Josephson junctions. In the classical case the equations of motion admit discrete breather by employing the already developed tech- niques for quantum information processing using Josephson junctions

  16. Multi-junction, monolithic solar cell using low-band-gap materials lattice matched to GaAs or Ge

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO); Friedman, Daniel J. (Lakewood, CO)

    2001-01-01T23:59:59.000Z

    A multi-junction, monolithic, photovoltaic solar cell device is provided for converting solar radiation to photocurrent and photovoltage with improved efficiency. The solar cell device comprises a plurality of semiconductor cells, i.e., active p/n junctions, connected in tandem and deposited on a substrate fabricated from GaAs or Ge. To increase efficiency, each semiconductor cell is fabricated from a crystalline material with a lattice constant substantially equivalent to the lattice constant of the substrate material. Additionally, the semiconductor cells are selected with appropriate band gaps to efficiently create photovoltage from a larger portion of the solar spectrum. In this regard, one semiconductor cell in each embodiment of the solar cell device has a band gap between that of Ge and GaAs. To achieve desired band gaps and lattice constants, the semiconductor cells may be fabricated from a number of materials including Ge, GaInP, GaAs, GaInAsP, GaInAsN, GaAsGe, BGaInAs, (GaAs)Ge, CuInSSe, CuAsSSe, and GaInAsNP. To further increase efficiency, the thickness of each semiconductor cell is controlled to match the photocurrent generated in each cell. To facilitate photocurrent flow, a plurality of tunnel junctions of low-resistivity material are included between each adjacent semiconductor cell. The conductivity or direction of photocurrent in the solar cell device may be selected by controlling the specific p-type or n-type characteristics for each active junction.

  17. FINE-GRAINED NANOCRYSTALLINE SILICON P-LAYER FOR HIGH OPEN CIRCUIT VOLTAGE A-SI:H SOLAR CELLS

    E-Print Network [OSTI]

    Deng, Xunming

    FINE-GRAINED NANOCRYSTALLINE SILICON P-LAYER FOR HIGH OPEN CIRCUIT VOLTAGE A-SI:H SOLAR CELLS of Michigan, Ann Arbor, MI 48109, USA ABSTRACT Hydrogenated amorphous silicon (a-Si:H) single- junction solar). It is found that the p-layer that leads to high Voc a-Si:H solar cells is a mixed-phase material that contains

  18. Conditions for synchronization in Josephson-junction arrays

    SciTech Connect (OSTI)

    Chernikov, A.A.; Schmidt, G. [Stevens Institute of Technology, Hoboken, New Jersey 07030 (United States)] [Stevens Institute of Technology, Hoboken, New Jersey 07030 (United States)

    1995-10-01T23:59:59.000Z

    An effective perturbation theoretical method has been developed to study the dynamics of Josephson-junction series arrays. It is shown that the inclusion of junction capacitances, which is often ignored, has a significant impact on synchronization. Comparison of analytic with computational results over a wide range of parameters shows excellent agreement.

  19. A fourier spectrometer for studying the radiation from Josephson Junctions

    SciTech Connect (OSTI)

    Verevkin, A.A.; Il`in, V.A.; Lipatov, A.P. [V.I. Lenin Moscow Pedagogical State Univ., Moscow (Russian Federation)

    1995-06-01T23:59:59.000Z

    The paper describes a Fourier spectrometer designed to study the radiation generated by a Josephson junction in the millimeter and FIR bands with a resolution of {approx}2 GHz in the two-pass mode and {approx}1 GHz in the multipass mode. A feature is that one Josephson junctions operates as both generator and detector at the same time.

  20. Conditions for synchronization in Josephson-junction arrays

    SciTech Connect (OSTI)

    Chernikov, A.A.; Schmidt, G. [Stevens Institute of Technology, Hoboken, NJ (United States)

    1995-12-31T23:59:59.000Z

    An effective perturbation theoretical method has been developed to study the dynamics of Josephson Junction series arrays. It is shown that the inclusion of Junction capacitances, often ignored, has a significant impact on synchronization. Comparison of analytic with computational results over a wide range of parameters shows excellent agreement.

  1. Josephson junctions in high-T/sub c/ superconductors

    DOE Patents [OSTI]

    Falco, C.M.; Lee, T.W.

    1981-01-14T23:59:59.000Z

    The invention includes a high T/sub c/ Josephson sperconducting junction as well as the method and apparatus which provides the junction by application of a closely controlled and monitored electrical discharge to a microbridge region connecting two portions of a superconducting film.

  2. Intermittency and low frequency noise in a Josephson junction

    SciTech Connect (OSTI)

    Xiao Wanru (Physics Division, Nanjing Architectural Institute (CN)); Yao Xixian (Department of Physics, Nanjing University (CN))

    1990-01-01T23:59:59.000Z

    The bifurcation, chaos, and intermittency in the {ital f}-biased Josephson junction are investigated by numerically integrating the equation of the Stewart-McCumber model with an interference {epsilon} cos {phi}'' term. In addition, the relationship between the low frequency noise and the routes to chaos in a Josephson junction is discussed.

  3. E-Print Network 3.0 - adhering junctions connecting Sample Search...

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

    S... . P. Benz, and J. E. Bonevich Abstract--The authors have made tall, uniform stacked Josephson junction... bar- rier of our niobium Josephson junctions and obtain working...

  4. Vortex radiation in long narrow Josephson junctions: Theory and experiment

    SciTech Connect (OSTI)

    Abdumalikov, A.A. Jr.; Ustinov, A.V. [Physikalisches Institut III, Universitaet Erlangen-Nuernberg, D-91058 Erlangen (Germany); Fistul, M.V. [Theoretische Physik III, Ruhr-Universitaet Bochum, D-44801 Bochum (Germany)

    2005-10-01T23:59:59.000Z

    We study theoretically and experimentally the dynamics of vortices in long, extremely narrow Josephson junctions. Using a variational approach, the current-voltage characteristics are calculated for junctions of different widths. The analytically and numerically calculated current-voltage characteristics show good agreement. We find that the decrease of the junction width leads to a substantial increase of the maximum velocity of vortices. Due to the interaction with stray magnetic fields outside the junction, the vortices radiate Cherenkov waves as they move in the junction. Locking of the vortex oscillation frequency to that of the Cherenkov radiation leads to novel resonances on the current-voltage characteristics. We observe such resonances in experiments, and their voltage positions and current magnitudes are in qualitative agreement with our theoretical analysis.

  5. Tandem junction amorphous semiconductor photovoltaic cell

    DOE Patents [OSTI]

    Dalal, V.L.

    1983-06-07T23:59:59.000Z

    A photovoltaic stack comprising at least two p[sup +]i n[sup +] cells in optical series, said cells separated by a transparent ohmic contact layer(s), provides a long optical path for the absorption of photons while preserving the advantageous field-enhanced minority carrier collection arrangement characteristic of p[sup +]i n[sup +] cells. 3 figs.

  6. Hetero-junction photovoltaic device and method of fabricating the device

    DOE Patents [OSTI]

    Aytug, Tolga; Christen, David K; Paranthaman, Mariappan Parans; Polat, Ozgur

    2014-02-10T23:59:59.000Z

    A hetero-junction device and fabrication method in which phase-separated n-type and p-type semiconductor pillars define vertically-oriented p-n junctions extending above a substrate. Semiconductor materials are selected for the p-type and n-type pillars that are thermodynamically stable and substantially insoluble in one another. An epitaxial deposition process is employed to form the pillars on a nucleation layer and the mutual insolubility drives phase separation of the materials. During the epitaxial deposition process, the orientation is such that the nucleation layer initiates propagation of vertical columns resulting in a substantially ordered, three-dimensional structure throughout the deposited material. An oxidation state of at least a portion of one of the p-type or the n-type semiconductor materials is altered relative to the other, such that the band-gap energy of the semiconductor materials differ with respect to stoichiometric compositions and the device preferentially absorbs particular selected bands of radiation.

  7. Cadmium-free junction fabrication process for CuInSe.sub.2 thin film solar cells

    DOE Patents [OSTI]

    Ramanathan, Kannan V. (Lakewood, CA); Contreras, Miguel A. (Golden, CA); Bhattacharya, Raghu N. (Littleton, CA); Keane, James (Lakewood, CA); Noufi, Rommel (Golden, CA)

    1999-01-01T23:59:59.000Z

    The present invention provides an economical, simple, dry and controllable semiconductor layer junction forming process to make cadmium free high efficiency photovoltaic cells having a first layer comprised primarily of copper indium diselenide having a thin doped copper indium diselenide n-type region, generated by thermal diffusion with a group II(b) element such as zinc, and a halide, such as chlorine, and a second layer comprised of a conventional zinc oxide bilayer. A photovoltaic device according the present invention includes a first thin film layer of semiconductor material formed primarily from copper indium diselenide. Doping of the copper indium diselenide with zinc chloride is accomplished using either a zinc chloride solution or a solid zinc chloride material. Thermal diffusion of zinc chloride into the copper indium diselenide upper region creates the thin n-type copper indium diselenide surface. A second thin film layer of semiconductor material comprising zinc oxide is then applied in two layers. The first layer comprises a thin layer of high resistivity zinc oxide. The second relatively thick layer of zinc oxide is doped to exhibit low resistivity.

  8. Quantum Fluctuations in Josephson Junction Comparators

    E-Print Network [OSTI]

    Thomas J. Walls; Timur V. Filippov; Konstantin K. Likharev

    2002-07-15T23:59:59.000Z

    We have developed a method for calculation of quantum fluctuation effects, in particular of the uncertainty zone developing at the potential curvature sign inversion, for a damped harmonic oscillator with arbitrary time dependence of frequency and for arbitrary temperature, within the Caldeira-Leggett model. The method has been applied to the calculation of the gray zone width Delta Ix of Josephson-junction balanced comparators driven by a specially designed low-impedance RSFQ circuit. The calculated temperature dependence of Delta Ix in the range 1.5 to 4.2K is in a virtually perfect agreement with experimental data for Nb-trilayer comparators with critical current densities of 1.0 and 5.5 kA/cm^2, without any fitting parameters.

  9. Quantum Computing with Atomic Josephson Junction Arrays

    E-Print Network [OSTI]

    Lin Tian; P. Zoller

    2003-06-12T23:59:59.000Z

    We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off resonant optical lattice. Raman lasers provide the "Josephson" tunneling, and the collision interaction between atoms represent the "capacitive" couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

  10. The World as a Dual Josephson Junction

    E-Print Network [OSTI]

    N. Tetradis

    2000-02-24T23:59:59.000Z

    We examine some of the implications of the field-theoretical mechanism for the localization of gauge fields on hypersurfaces in higher-dimensional bulk space-time. This mechanism exploits the analogy between confinement and dual superconductivity. In the simplest case of a photon localized on a (2+1)-dimensional surface in a (3+1)-dimensional bulk, we argue that the system behaves like a dual Josephson junction. This implies that the effective gauge theory on the surface is not free, but displays weak confinement with a linear potential. We comment on the relevance of our results for the realistic case of a (3+1)-dimensional surface in a space-time with one or more extra dimensions.

  11. Gauge Theories of Josephson Junction Arrays

    E-Print Network [OSTI]

    M. C. Diamantini; P. Sodano; C. A. Trugenberger

    1995-11-23T23:59:59.000Z

    We show that the zero-temperature physics of planar Josephson junction arrays in the self-dual approximation is governed by an Abelian gauge theory with periodic mixed Chern-Simons term describing the charge-vortex coupling. The periodicity requires the existence of (Euclidean) topological excitations which determine the quantum phase structure of the model. The electric-magnetic duality leads to a quantum phase transition between a superconductor and a superinsulator at the self-dual point. We also discuss in this framework the recently proposed quantum Hall phases for charges and vortices in presence of external offset charges and magnetic fluxes: we show how the periodicity of the charge-vortex coupling can lead to transitions to anyon superconductivity phases. We finally generalize our results to three dimensions, where the relevant gauge theory is the so-called BF system, with an antisymmetric Kalb-Ramond gauge field.

  12. Quantum computing with atomic Josephson junction arrays

    SciTech Connect (OSTI)

    Tian Lin; Zoller, P. [Institute for Theoretical Physics, University of Innsbruck, A-6020 Innsbruck (Austria)

    2003-10-01T23:59:59.000Z

    We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off-resonant optical lattice. Raman lasers provide the 'Josephson' tunneling, and the collision interaction between atoms represent the 'capacitive' couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single-qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

  13. Advanced Concepts in Josephson Junction Reflection Amplifiers

    E-Print Network [OSTI]

    Pasi Lähteenmäki; Visa Vesterinen; Juha Hassel; G. S. Paraoanu; Heikki Seppä; Pertti Hakonen

    2014-05-20T23:59:59.000Z

    Low-noise amplification atmicrowave frequencies has become increasingly important for the research related to superconducting qubits and nanoelectromechanical systems. The fundamental limit of added noise by a phase-preserving amplifier is the standard quantum limit, often expressed as noise temperature $T_{q} = \\hbar {\\omega}/2k_{B}$. Towards the goal of the quantum limit, we have developed an amplifier based on intrinsic negative resistance of a selectively damped Josephson junction. Here we present measurement results on previously proposed wide-band microwave amplification and discuss the challenges for improvements on the existing designs. We have also studied flux-pumped metamaterial-based parametric amplifiers, whose operating frequency can be widely tuned by external DC-flux, and demonstrate operation at $2\\omega$ pumping, in contrast to the typical metamaterial amplifiers pumped via signal lines at $\\omega$.

  14. Ternary metal-rich sulfide with a layered structure

    DOE Patents [OSTI]

    Franzen, Hugo F. (Ames, IA); Yao, Xiaoqiang (Ames, IA)

    1993-08-17T23:59:59.000Z

    A ternary Nb-Ta-S compound is provided having the atomic formula, Nb.sub.1.72 Ta.sub.3.28 S.sub.2, and exhibiting a layered structure in the sequence S-M3-M2-M1-M2-M3-S wherein S represents sulfur layers and M1, M2, and M3 represent Nb/Ta mixed metal layers. This sequence generates seven sheets stacked along the [001] direction of an approximate body centered cubic crystal structure with relatively weak sulfur-to-sulfur van der Waals type interactions between adjacent sulfur sheets and metal-to-metal bonding within and between adjacent mixed metal sheets.

  15. Josephson-junction arrays with long-range interactions

    SciTech Connect (OSTI)

    Harbaugh, J.K.; Stroud, D. [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States)] [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States)

    1997-10-01T23:59:59.000Z

    We calculate the current-voltage (IV) characteristics of a Josephson-junction array with long-range interactions. The array consists of two sets of equally spaced parallel superconducting wires placed at right angles. A Josephson junction is formed at every point wherever the wires cross. We treat each such junction as an overdamped resistively shunted junction, and each wire segment between two junctions as a similar resistively shunted junction with a much higher critical current. The IV characteristics are obtained by solving the coupled Josephson equations numerically. We find that, for a sufficiently large number of wires, the critical current saturates at a finite value because of the wire inductance, in excellent agreement with experiment. The calculated IV characteristics also show a striking hysteresis, even though each of the individual junctions is {ital nonhysteretic}. The hysteresis results from a global redistribution of current flow on the upper and lower voltage branches, and is also in excellent agreement with experiment. {copyright} {ital 1997} {ital The American Physical Society}

  16. Mechanical deformations of boron nitride nanotubes in crossed junctions

    SciTech Connect (OSTI)

    Zhao, Yadong; Chen, Xiaoming; Ke, Changhong, E-mail: cke@binghamton.edu [Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, New York 13902 (United States); Park, Cheol [NASA Langley Research Center, Hampton, Virginia 23681 (United States); Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Fay, Catharine C. [NASA Langley Research Center, Hampton, Virginia 23681 (United States); Stupkiewicz, Stanislaw [Institute of Fundamental Technological Research, Warsaw (Poland)

    2014-04-28T23:59:59.000Z

    We present a study of the mechanical deformations of boron nitride nanotubes (BNNTs) in crossed junctions. The structure and deformation of the crossed tubes in the junction are characterized by using atomic force microscopy. Our results show that the total tube heights are reduced by 20%–33% at the crossed junctions formed by double-walled BNNTs with outer diameters in the range of 2.21–4.67?nm. The measured tube height reduction is found to be in a nearly linear relationship with the summation of the outer diameters of the two tubes forming the junction. The contact force between the two tubes in the junction is estimated based on contact mechanics theories and found to be within the range of 4.2–7.6 nN. The Young's modulus of BNNTs and their binding strengths with the substrate are quantified, based on the deformation profile of the upper tube in the junction, and are found to be 1.07?±?0.11 TPa and 0.18–0.29 nJ/m, respectively. Finally, we perform finite element simulations on the mechanical deformations of the crossed BNNT junctions. The numerical simulation results are consistent with both the experimental measurements and the analytical analysis. The results reported in this paper contribute to a better understanding of the structural and mechanical properties of BNNTs and to the pursuit of their applications.

  17. The radio-frequency impedance of individual intrinsic Josephson junctions

    SciTech Connect (OSTI)

    Leiner, Johannes; Saleem, Sajid; Fenton, J. C.; Warburton, P. A. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH (United Kingdom); Yamamoto, Takashi; Kadowaki, Kazuo [Institute of Materials Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)

    2009-12-21T23:59:59.000Z

    We have measured the response of an array of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} intrinsic Josephson junctions to irradiation at 3 GHz. By measuring the dependence of the switching current upon the radio-frequency current for five of the junctions in the array we show quantitatively that the junctions have identical impedances at 3 GHz, this impedance being given by the inverse of the slope of the current-voltage characteristics.

  18. Dissipative dynamics of a Josephson junction in the Bose gases

    SciTech Connect (OSTI)

    Barankov, R.A. [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Burmistrov, S.N. [RRC 'Kurchatov Institute', Kurchatov Sq.1, 123182 Moscow (Russian Federation)

    2003-01-01T23:59:59.000Z

    The dissipative dynamics of a Josephson junction in Bose gases is considered within the framework of the model of a tunneling Hamiltonian. The effective action that describes the dynamics of the phase difference across the junction is derived using the functional integration method. The dynamic equation obtained for the phase difference across the junction is analyzed for the finite temperatures in the low-frequency limit involving the radiation terms. The asymmetric case of the Bose gases with the different order parameters is calculated as well.

  19. adjacent non-cancerous ductal: Topics by E-print Network

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

    many nets, those using them were doingwell. The schooner Sarah 312 Geological Setting, Mineral Resources and ancient works of Samos and adjacent islands of the Aegean Sea, 26-30...

  20. E-Print Network 3.0 - adjacent genetic loci Sample Search Results

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

    search results for: adjacent genetic loci Page: << < 1 2 3 4 5 > >> 1 Introductory Biology Genetics Problems Do NOT use a Punnett square to solve any of these problems (except...

  1. E-Print Network 3.0 - aquatic environments adjacent Sample Search...

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

    for: aquatic environments adjacent Page: << < 1 2 3 4 5 > >> 1 Journal of Animal Ecology 2009, 78, 338345 doi: 10.1111j.1365-2656.2008.01498.x 2008 The Authors. Journal...

  2. Thermal buckling of metal oil tanks subject to an adjacent fire 

    E-Print Network [OSTI]

    Liu, Ying

    2011-01-01T23:59:59.000Z

    Fire is one of the main hazards associated with storage tanks containing flammable liquids. These tanks are usually closely spaced and in large groups, so where a petroleum fire occurs, adjacent tanks are susceptible to ...

  3. Thermal buckling of metal oil tanks subject to an adjacent fire 

    E-Print Network [OSTI]

    Liu, Ying

    2011-11-22T23:59:59.000Z

    Fire is one of the main hazards associated with storage tanks containing flammable liquids. These tanks are usually closely spaced and in large groups, so where a petroleum fire occurs, adjacent tanks are susceptible to ...

  4. Supercurrent-Induced Temperature Gradient across a Nonequilibrium SNS Josephson Junction M. S. Crosser,1

    E-Print Network [OSTI]

    Birge, Norman

    Supercurrent-Induced Temperature Gradient across a Nonequilibrium SNS Josephson Junction M. S direction. The feature represents an effective temperature gradient across the SNS Josephson junction Josephson junction (SNS JJ) into a `` junction'' by driving the electron energy distribution far from

  5. Asymmetric noise probed with a Josephson junction Q. Le Masne,1

    E-Print Network [OSTI]

    Boyer, Edmond

    Asymmetric noise probed with a Josephson junction Q. Le Masne,1 H. Pothier,1, Norman O. Birge,2 C are measured using a Josephson junction. The current noise adds to the bias current of the Josephson junction], consists in using a Josephson junction (JJ) as a large bandwidth on-chip noise detector [7, 8, 9]. It has

  6. Cooper pair transport and Coulomb blockade in one dimensional Josephson junction arrays

    E-Print Network [OSTI]

    Haviland, David

    Cooper pair transport and Coulomb blockade in one dimensional Josephson junction arrays Peter Å¡Ë?ogskoletryckeriet, Stockholm, 2000 #12; Abstract One dimensional Josephson junction arrays have been fabricated, measured small capacitance Josephson junction is described using a Serial Resistive and Inductive Junction (SRLJ

  7. Asymmetric Noise Probed with a Josephson Junction Q. Le Masne,1

    E-Print Network [OSTI]

    Birge, Norman

    Asymmetric Noise Probed with a Josephson Junction Q. Le Masne,1 H. Pothier,1,* Norman O. Birge,2 C of the current through a tunnel junction are measured using a Josephson junction. The current noise adds to the bias current of the Josephson junction and affects its switching out of the supercurrent branch

  8. Superconducting and Insulating Behavior in One-Dimensional Josephson Junction Arrays

    E-Print Network [OSTI]

    Haviland, David

    Superconducting and Insulating Behavior in One-Dimensional Josephson Junction Arrays David B Stockholm, Sweden Experiments on one-dimensional small capacitance Josephson Junction ar- rays are described shunted junction model of classical Josephson junctions. PACS numbers: 73.40Gk, 74.50+r 1. INTRODUCTION

  9. Long Josephson junction in a resonant cavity I. Tornes* and D. Stroud

    E-Print Network [OSTI]

    Stroud, David

    Long Josephson junction in a resonant cavity I. Tornes* and D. Stroud Department of Physics Josephson junctions. When a soliton is present in the junction corresponding to a quantum of magnetic flux s : 74.81.Fa, 74.72. h, 74.25.Nf I. INTRODUCTION Josephson junction arrays have now been studied for more

  10. Microwave Photon Counter Based on Josephson Junctions Y.-F. Chen,1,* D. Hover,1

    E-Print Network [OSTI]

    Saffman, Mark

    Microwave Photon Counter Based on Josephson Junctions Y.-F. Chen,1,* D. Hover,1 S. Sendelbach,1 L on the current-biased Josephson junction. The junction is tuned to absorb single microwave photons from optical photon counters, it is natural to consider the Josephson junction--a nonlinear, nondissipative

  11. Modeling the Physical and Biochemical Influence of Ocean Thermal Energy Conversion Plant Discharges into their Adjacent Waters

    Broader source: Energy.gov [DOE]

    Modeling the Physical and Biochemical Influence of Ocean Thermal Energy Conversion Plant Discharges into their Adjacent Waters

  12. Power dissipation in a single molecule junction: Tracking energy levels

    E-Print Network [OSTI]

    Yaghoob Naimi; Javad Vahedi

    2014-12-05T23:59:59.000Z

    Motivated by recent work [Lee et al. Nature {\\bf 489}, 209 (2013)], on asymmetry features of heat dissipation in the electrodes of molecular junctions, we put forward an idea as a result of heat dissipation in the electrodes. Based on tight-binding model and a generalized Green's function formalism, we describe the conditions under which heat dissipation shows symmetry characteristic and does not depend on the bias polarity. We also show the power dissipated in the junction can be used to detect which energy levels of molecule junction play more or less role in the transmission process. We present this idea by studying a simple toy model and Au-$C_{60}$-Au junction.

  13. EA-1037: Uranium Lease Management Program, Grand Junction, Colorado

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts of the U.S. Department of Energy's Grand Junction Projects Office's proposal to maintain and preserve the nation's immediately accessible supply of...

  14. Manipulating Josephson junctions in thin-films by nearby vortices

    SciTech Connect (OSTI)

    Kogan, V.G.; Mints, R.G.

    2014-07-01T23:59:59.000Z

    It is shown that a vortex trapped in one of the banks of a planar edge-type Josephson junction in a narrow thin-film superconducting strip can change drastically the dependence of the junction critical current on the applied field, I-c(H). When the vortex is placed at certain discrete positions in the strip middle, the pattern I-c(H) has zero at H = 0 instead of the traditional maximum of '0-type' junctions. The number of these positions is equal to the number of vortices trapped at the same location. When the junction-vortex separation exceeds similar to W, the strip width, I-c(H) is no longer sensitive to the vortex presence. The same is true for any separation if the vortex approaches the strip edges. (C) 2014 Elsevier B.V. All rights reserved.

  15. Josephson Junctions and Devices fabricated by Focused Electron Beam Irradiation

    E-Print Network [OSTI]

    Booij, Wilfred Edwin

    Josephson Junctions and Devices fabricated by Focused Electron Beam Irradiation Wilfred Edwin Booij Gonville and Caius College Cambridge A dissertation submitted for the degree of Doctor of Philosophy at the University of Cambridge December 1997... Summary Josephson Junctions and Devices fabricated by Focused Electron Beam Irradiation The irradiation of high Tc superconducting thin films with a focused electron beam, such as that obtained in a scanning transmission electron microscope (STEM), can...

  16. From Josephson junction metamaterials to tunable pseudo-cavities

    E-Print Network [OSTI]

    D. Zueco; C. Fernández-Juez; J. Yago; U. Naether; B. Peropadre; J. J. García-Ripoll; J. J. Mazo

    2013-05-21T23:59:59.000Z

    The scattering through a Josephson junction interrupting a superconducting line is revisited including power leakage. We discuss also how to make tunable and broadband resonant mirrors by concatenating junctions. As an application, we show how to construct cavities using these mirrors, thus connecting two research fields: JJ quantum metamaterials and coupled cavity arrays. We finish by discussing the first non-linear corrections to the scattering and their measurable effects.

  17. Building biomedical materials layer-by-layer

    E-Print Network [OSTI]

    Hammond, Paula T.

    In this materials perspective, the promise of water based layer-by-layer (LbL) assembly as a means of generating drug-releasing surfaces for biomedical applications, from small molecule therapeutics to biologic drugs and ...

  18. High-frequency wave sources using Josephson-junction arrays

    SciTech Connect (OSTI)

    Wan, Kelin.

    1991-01-01T23:59:59.000Z

    Results from Josephson-junction arrays used as high-frequency wave sources are presented. Phase-locked Josephson-junction arrays having a large number of junctions were developed to meet the need for compact submillimeter-wave sources for use in such applications as satellite communications are receivers for radioastronomical observations. The design, fabrication processes, and measurement are discussed. Distributed arrays of 40 junctions in which all Josephson junctions are placed at wavelength intervals were fabricated and tested. Such arrays can deliver about 1 [mu]W of power into a 20-60 [Omega] load resistor in the frequency ranger from 100 to 500 GHz, the upper limit being set by the large loss of the superconducting microstrip. Compact arrays were designed and fabricated to eliminate the loss of the superconducting microstrip. Those arrays have also demonstrated an output power level about 1 [mu]W into a 15 [Omega] load from 100 GHz up to 620 GHz. Characteristics of the Josephson junction source, including the power level, impedance matching, the tunability, the radiation linewidth, and tuning rate (or frequency-modulation) are discussed.

  19. Superconducting structure with layers of niobium nitride and aluminum nitride

    DOE Patents [OSTI]

    Murduck, James M. (Lisle, IL); Lepetre, Yves J. (Lauris, FR); Schuller, Ivan K. (Woodridge, IL); Ketterson, John B. (Evanston, IL)

    1989-01-01T23:59:59.000Z

    A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources.

  20. Superconducting structure with layers of niobium nitride and aluminum nitride

    DOE Patents [OSTI]

    Murduck, J.M.; Lepetre, Y.J.; Schuller, I.K.; Ketterson, J.B.

    1989-07-04T23:59:59.000Z

    A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources. 8 figs.

  1. EA-1338: Transfer of the Department of Energy Grand Junction Office to Non-DOE Ownership, Grand Junction, Colorado

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts for the proposed transfer of real and personal property at the U.S. Department of Energy's Grand Junction Office to non-DOE ownership.

  2. 2. HIGH-LOv~ JUNCTION FORY_,\\'UO AN EXPERIMENTAL STUDY OF AL-ALLOYED:'p+ JUNCT;[ONS FOR SSF SOLAR CELT.S As temperature rises en..!."

    E-Print Network [OSTI]

    del Alamo, Jesús A.

    . Luque formed. The deposited Al diss Instituto de Energia Solar {E.T,S,I.T,} phase composition given2. HIGH-LOv~ JUNCTION FORY_,\\'UO AN EXPERIMENTAL STUDY OF AL-ALLOYED:§'p+ JUNCT;[ONS FOR SSF SOLAR+pp+ bifacial SSF solar cells are used to experimentally analyse the interphase in a similar way a 5i layer

  3. Design, fabrication, and analysis of p-channel arsenide/antimonide hetero-junction tunnel transistors

    SciTech Connect (OSTI)

    Rajamohanan, Bijesh, E-mail: bor5067@psu.edu; Mohata, Dheeraj; Hollander, Matthew; Datta, Suman [Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Zhu, Yan; Hudait, Mantu [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States); Jiang, Zhengping; Klimeck, Gerhard [Department of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906 (United States)

    2014-01-28T23:59:59.000Z

    In this paper, we demonstrate InAs/GaSb hetero-junction (hetJ) and GaSb homo-junction (homJ) p-channel tunneling field effect transistors (pTFET) employing a low temperature atomic layer deposited high-? gate dielectric. HetJ pTFET exhibited drive current of 35 ?A/?m in comparison to homJ pTFET, which exhibited drive current of 0.3 ?A/?m at V{sub DS}?=??0.5?V under DC biasing conditions. Additionally, with pulsing of 1 ?s gate voltage, hetJ pTFET exhibited enhanced drive current of 85 ?A/?m at V{sub DS}?=??0.5?V, which is the highest reported in the category of III-V pTFET. Detailed device characterization was performed through analysis of the capacitance-voltage characteristics, pulsed current-voltage characteristics, and x-ray diffraction studies.

  4. Fabrication and measurements of hybrid Nb/Al Josephson junctions and flux qubits with pi-shifters

    E-Print Network [OSTI]

    A. V. Shcherbakova; K. G. Fedorov; K. V. Shulga; V. V. Ryazanov; V. V. Bolginov; V. A Oboznov; S. V. Egorov; V. O. Shkolnikov; M. J. Wolf; D. Beckmann; A. V. Ustinov

    2014-05-02T23:59:59.000Z

    We describe fabrication and testing of composite flux qubits combining Nb- and Al-based superconducting circuit technology. This hybrid approach to making qubits allows for employing pi-phase shifters fabricated using well-established Nb-based technology of superconductor-ferromagnet-superconductor Josephson junctions. The important feature here is to obtain high interface transparency between Nb and Al layers without degrading sub-micron shadow mask. We achieve this by in-situ Ar etching using e-beam gun. Shadow-evaporated Al/AlOx/Al Josephson junctions with Nb bias pads show the expected current-voltage characteristics with reproducible critical currents. Using this technique, we fabricated composite Nb/Al flux qubits with Nb/CuNi/Nb pi-shifters and measured their magnetic field response. The observed offset between the field responses of the qubits with and without pi-junction is attributed to the pi phase shift. The reported approach can be used for implementing a variety of hybrid Nb/Al superconducting quantum circuits.

  5. Noise and microresonance of critical current in Josephson junction induced by Kondo trap states

    E-Print Network [OSTI]

    Ansari, Mohammad H

    2011-01-01T23:59:59.000Z

    We analyze the impact of trap states in the oxide layer of a superconducting tunnel junctions, on the fluctuation of the Josephson critical current, thus on coherence in superconducting qubits. Two mechanisms are usually considered: the current blockage due to repulsion at the occupied trap states, and the noise from electrons hopping across a trap. We extend previous studies of noninteracting traps to the case where the traps have on-site electron repulsion inside one ballistic channel. The repulsion not only allows the appropriate temperature dependence of 1/f noise, but also is a control to the coupling between the computational qubit and the spurious two-level systems inside the oxide dielectric. We use second order perturbation theory which allows to obtain analytical formulae for the interacting bound states and spectral weights, limited to small and intermediate repulsions. Remarkably, it still reproduces the main features of the model as identified from the Numerical Renormalization Group. We present ...

  6. Electrical Characterization of Layer-Exchange Solid-Phase Epitaxy Si Diode Junctions

    E-Print Network [OSTI]

    Technische Universiteit Delft

    . The controllability of the growth location and dimensions, practically unchanged when the downscale is reduced nitride (SiNx) spacer technology [14], mature in our research laboratory, has L 408 #12;been used: a 300

  7. InGaAsN/GaAs heterojunction for multi-junction solar cells

    DOE Patents [OSTI]

    Kurtz, Steven R. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Klem, John F. (Albuquerque, NM); Jones, Eric D. (Edgewood, NM)

    2001-01-01T23:59:59.000Z

    An InGaAsN/GaAs semiconductor p-n heterojunction is disclosed for use in forming a 0.95-1.2 eV bandgap photodetector with application for use in high-efficiency multi-junction solar cells. The InGaAsN/GaAs p-n heterojunction is formed by epitaxially growing on a gallium arsenide (GaAs) or germanium (Ge) substrate an n-type indium gallium arsenide nitride (InGaAsN) layer having a semiconductor alloy composition In.sub.x Ga.sub.1-x As.sub.1-y N.sub.y with 0layer, with the InGaAsN and GaAs layers being lattice-matched to the substrate. The InGaAsN/GaAs p-n heterojunction can be epitaxially grown by either molecular beam epitaxy (MBE) or metalorganic chemical vapor deposition (MOCVD). The InGaAsN/GaAs p-n heterojunction provides a high open-circuit voltage of up to 0.62 volts and an internal quantum efficiency of >70%.

  8. Interference effects in isolated Josephson junction arrays with geometric symmetries

    E-Print Network [OSTI]

    D. A. Ivanov; L. B. Ioffe; V. B. Geshkenbein; G. Blatter

    2001-02-13T23:59:59.000Z

    As the size of a Josephson junction is reduced, charging effects become important and the superconducting phase across the link turns into a periodic quantum variable. Isolated Josephson junction arrays are described in terms of such periodic quantum variables and thus exhibit pronounced quantum interference effects arising from paths with different winding numbers (Aharonov-Casher effects). These interference effects have strong implications for the excitation spectrum of the array which are relevant in applications of superconducting junction arrays for quantum computing. The interference effects are most pronounced in arrays composed of identical junctions and possessing geometric symmetries; they may be controlled by either external gate potentials or by adding/removing charge to/from the array. Here we consider a loop of N identical junctions encircling one half superconducting quantum of magnetic flux. In this system, the ground state is found to be non-degenerate if the total number of Cooper pairs on the array is divisible by N, and doubly degenerate otherwise (after the stray charges are compensated by the gate voltages).

  9. Measure Guideline: Optimizing the Configuration of Flexible Duct Junction Boxes

    SciTech Connect (OSTI)

    Beach, R.; Burdick, A.

    2014-03-01T23:59:59.000Z

    This measure guideline offers additional recommendations to heating, ventilation, and air conditioning (HVAC) system designers for optimizing flexible duct, constant-volume HVAC systems using junction boxes within Air Conditioning Contractors of America (ACCA) Manual D guidance (Rutkowski, H. Manual D -- Residential Duct Systems, 3rd edition, Version 1.00. Arlington, VA: Air Conditioning Contractors of America, 2009.). IBACOS used computational fluid dynamics software to explore and develop guidance to better control the airflow effects of factors that may impact pressure losses within junction boxes among various design configurations (Beach, R., Prahl, D., and Lange, R. CFD Analysis of Flexible Duct Junction Box Design. Golden, CO: National Renewable Energy Laboratory, submitted for publication 2013). These recommendations can help to ensure that a system aligns more closely with the design and the occupants' comfort expectations. Specifically, the recommendations described herein show how to configure a rectangular box with four outlets, a triangular box with three outlets, metal wyes with two outlets, and multiple configurations for more than four outlets. Designers of HVAC systems, contractors who are fabricating junction boxes on site, and anyone using the ACCA Manual D process for sizing duct runs will find this measure guideline invaluable for more accurately minimizing pressure losses when using junction boxes with flexible ducts.

  10. Microwave coupling of frequency-locked Josephson junction arrays

    SciTech Connect (OSTI)

    Song, I.; Eom, Y.; Park, G. [Department of Physics, Sogang University, Seoul 100-611 (Korea)] [Department of Physics, Sogang University, Seoul 100-611 (Korea); Lee, E.; Park, S. [Electronic Materials Laboratory, Samsung Advanced Institute of Technology, Suwon (Korea)] [Electronic Materials Laboratory, Samsung Advanced Institute of Technology, Suwon (Korea)

    1997-06-01T23:59:59.000Z

    A high temperature superconducting YBa{sub 2}Cu{sub 3}O{sub y} array of five Josephson junctions designed with additional coupling lines has been developed to demonstrate the effects of frequency locking and impedance matching for applications such as oscillators, mixers, and detectors. The Josephson self-radiation power was directly detected by a superheterodyne receiver, and Shapiro steps were also measured. The Josephson self-radiation properties reveal good quality of phase locking and microwave coupling with external circuits. The maximum self-radiation power of our array is about 50 pW which is several ten times higher than that of a single Josephson junction, and its peak point exactly satisfies the Josephson current-voltage relation. The Shapiro-step measurements show that the behavior of current-voltage curve depends on the effective inductance of coupling lines which affects the total impedance of Josephson junction array and microwave coupling. The Josephson oscillation frequency was obtained up to about 880 GHz which is 73{percent} of the maximum available frequency calculated from the characteristic voltage of the Josephson junctions. Experimental results show that this type of Josephson junction array can improve the Josephson self-radiation power and increase the maximum detectable frequency. {copyright} {ital 1997 American Institute of Physics.}

  11. Theoretical exploration of Josephson Plasma Emission in Intrinsic Josephson Junctions

    SciTech Connect (OSTI)

    Tachiki, M.; Machida, M.

    2000-07-18T23:59:59.000Z

    In this paper, the authors theoretically predict the best efficient way for electromagnetic wave emission by Josephson plasma excitation in intrinsic Josephson junctions. First, they briefly derive basic equations describing dynamics of phase differences inside junction sites in intrinsic Josephson junctions, and review the nature of Josephson plasma excitation modes based on the equations. Especially, they make an attention to that Josephson plasma modes have much different dispersion relations depending on the propagating directions and their different modes can be recognized as N standing waves propagating along ah-plane in cases of finite stacked systems composed of N junctions. Second, they consider how to excite their modes and point out that excitations of in-phase mode with the highest propagation velocity among their N modes are the most efficient way for electromagnetic wave emissions. Finally, they clarify that in-phase excitations over all junctions are possible by using Josephson vortex flow states. They show simulation results of Josephson vortex flow states resonating with some Josephson plasma modes and predict that superradiance of electromagnetic field may occur in rectangular vortex flow state in which spatiotemporal oscillations of electromagnetic fields are perfectly in-phase.

  12. Breathers in Josephson junction ladders: Resonances and electromagnetic wave spectroscopy A. E. Miroshnichenko, S. Flach, and M. V. Fistul

    E-Print Network [OSTI]

    Flach, Sergej

    Breathers in Josephson junction ladders: Resonances and electromagnetic wave spectroscopy A. E localized states discrete breathers and linear electromagnetic excitations EE's in Josephson junction lattices 6 , and localized resistive states in Josephson junction arrays 7­10 . The latter systems

  13. Junction-based field emission structure for field emission display

    DOE Patents [OSTI]

    Dinh, Long N. (Concord, CA); Balooch, Mehdi (Berkeley, CA); McLean, II, William (Oakland, CA); Schildbach, Marcus A. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A junction-based field emission display, wherein the junctions are formed by depositing a semiconducting or dielectric, low work function, negative electron affinity (NEA) silicon-based compound film (SBCF) onto a metal or n-type semiconductor substrate. The SBCF can be doped to become a p-type semiconductor. A small forward bias voltage is applied across the junction so that electron transport is from the substrate into the SBCF region. Upon entering into this NEA region, many electrons are released into the vacuum level above the SBCF surface and accelerated toward a positively biased phosphor screen anode, hence lighting up the phosphor screen for display. To turn off, simply switch off the applied potential across the SBCF/substrate. May be used for field emission flat panel displays.

  14. Escape Time of Josephson Junctions for Signal Detection

    E-Print Network [OSTI]

    Addesso, P; Pierro, V

    2014-01-01T23:59:59.000Z

    In this Chapter we investigate with the methods of signal detection the response of a Josephson junction to a perturbation to decide if the perturbation contains a coherent oscillation embedded in the background noise. When a Josephson Junction is irradiated by an external noisy source, it eventually leaves the static state and reaches a steady voltage state. The appearance of a voltage step allows to measure the time spent in the metastable state before the transition to the running state, thus defining an escape time. The distribution of the escape times depends upon the characteristics of the noise and the Josephson junction. Moreover, the properties of the distribution depends on the features of the signal (amplitude, frequency and phase), which can be therefore inferred through the appropriate signal processing methods. Signal detection with JJ is interesting for practical purposes, inasmuch as the superconductive elements can be (in principle) cooled to the absolute zero and therefore can add (in practi...

  15. Bloch Inductance in Small-Capacitance Josephson Junctions

    SciTech Connect (OSTI)

    Zorin, A.B. [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany)

    2006-04-28T23:59:59.000Z

    We show that the electrical impedance of a small-capacitance Josephson junction also includes, in addition to the capacitive term -i/{omega}C{sub B}, an inductive term i{omega}L{sub B}. Similar to the known Bloch capacitance C{sub B}(q), the Bloch inductance L{sub B}(q) also depends periodically on the quasicharge, q, and its maximum value achieved at q=e(mod 2e) always exceeds the value of the Josephson inductance of this junction L{sub J}({phi}) at fixed {phi}=0. The effect of the Bloch inductance on the dynamics of a single junction and a one-dimensional array is described.

  16. Differences in potassium forms between cutans and adjacent soil matrix in a Grey Clay Soil

    E-Print Network [OSTI]

    Boyer, Edmond

    Differences in potassium forms between cutans and adjacent soil matrix in a Grey Clay Soil Fan Liu1 , R. J. Gilkes, R. D. Hart, and A. Bruand2 Department of Soil Science and Plant Nutrition, Faculty are common fabric features in soil and represent foci of chemical and biological reactions. The influence

  17. Advancements in accuracy of the alanine EPR dosimetry Part III: Usefulness of an adjacent reference sample

    E-Print Network [OSTI]

    Advancements in accuracy of the alanine EPR dosimetry system Part III: Usefulness of an adjacent Instruments, Inc, EPR Division, Billerica, MA 01821-3957, USA Received 26 January 2000; accepted 28 February Paramagnetic Resonance (EPR) spectral analysis. Small uncontrollable variations of the EPR spectrometer

  18. 2D and 3D mesh graphs, 39 adjacency matrix, 5, 13

    E-Print Network [OSTI]

    Kepner, Jeremy

    maximal independent set, 35 memory hierarchy, 290 minimum paths, 26 minimum spanning tree, 55 monotype deterministic, 161 fast generation, 157 generation, 143 interpretation, 155 real, 161 stochastic, 152, 161 multiplication, 31 sparse reference, 291 sparsity, 220, 226 spherical projection, 246 stochastic adjacency matrix

  19. Successes, Challenges, Lessons Learned in Land Use Planning Efforts Adjacent to an LRT Station

    E-Print Network [OSTI]

    Minnesota, University of

    Successes, Challenges, Lessons Learned in Land Use Planning Efforts Adjacent to an LRT Station interest in "new outreach methods" ·!Demonstrated value added in more collaborative process #12;Lessons Learned 1.! Begin internal & external outreach earlier 2.! Our "good ideas" were not necessarily good

  20. Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent genes

    E-Print Network [OSTI]

    Nachman, Michael

    Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent, Kobe, Japan, October 9, 2008 (received for review July 27, 2008) Sterility is common in hybrids between). Although multiple loci for plant hybrid sterility have been identified, it remains unknown how alleles

  1. Comparison of measurements and simulations of series-parallel incommensurate area SQUID arrays fabricated from Y Ba Cu O ion damage Josephson junctions

    E-Print Network [OSTI]

    Cybart, Shane A.

    2014-01-01T23:59:59.000Z

    3 O 7?? ion damage Josephson junctions Shane A. Cybart, 1,2 Cu 3 O 7?? thin ?lm ion damage Josephson junctions. Theconsisted of a grid of Josephson junctions with 28 junctions

  2. Environmental Audit of the Grand Junction Projects Office

    SciTech Connect (OSTI)

    Not Available

    1991-08-01T23:59:59.000Z

    The Grand Junction Projects Office (GJPO) is located in Mesa County, Colorado, immediately south and west of the Grand Junction city limits. The US Atomic Energy Commission (AEC) established the Colorado Raw Materials Office at the present-day Grand Junction Projects Office in 1947, to aid in the development of a viable domestic uranium industry. Activities at the site included sampling uranium concentrate; pilot-plant milling research, including testing and processing of uranium ores; and operation of a uranium mill pilot plant from 1954 to 1958. The last shipment of uranium concentrate was sent from GJPO in January, 1975. Since that time the site has been utilized to support various DOE programs, such as the former National Uranium Resource Evaluation (NURE) Program, the Uranium Mill Tailings Remedial Action Project (UMTRAP), the Surplus Facilities Management Program (SFMP), and the Technical Measurements Center (TMC). All known contamination at GJPO is believed to be the result of the past uranium milling, analyses, and storage activities. Hazards associated with the wastes impounded at GJPO include surface and ground-water contamination and potential radon and gamma-radiation exposure. This report documents the results of the Baseline Environmental Audit conducted at Grand Junction Projects Office (GJPO) located in Grand Junction, Colorado. The Grand Junction Baseline Environmental Audit was conducted from May 28 to June 12, 1991, by the Office of Environmental Audit (EH-24). This Audit evaluated environmental programs and activities at GJPO, as well as GJPO activities at the State-Owned Temporary Repository. 4 figs., 12 tabs.

  3. Observation of negative absolute resistance in a Josephson junction

    E-Print Network [OSTI]

    J. Nagel; D. Speer; T. Gaber; A. Sterck; R. Eichhorn; P. Reimann; K. Ilin; M. Siegel; D. Koelle; R. Kleiner

    2008-01-28T23:59:59.000Z

    We experimentally demonstrate the occurrence of negative absolute resistance (NAR) up to about $-1\\Omega$ in response to an externally applied dc current for a shunted Nb-Al/AlO$_x$-Nb Josephson junction, exposed to a microwave current at frequencies in the GHz range. The realization (or not) of NAR depends crucially on the amplitude of the applied microwave current. Theoretically, the system is described by means of the resistively and capacitively shunted junction model in terms of a moderately damped, classical Brownian particle dynamics in a one-dimensional potential. We find excellent agreement of the experimental results with numerical simulations of the model.

  4. Testing axion physics in a Josephson junction environment

    E-Print Network [OSTI]

    Beck, Christian

    2011-01-01T23:59:59.000Z

    We suggest that experiments based on Josephson junctions, SQUIDS, and coupled Josephson qubits can be used to construct a resonant environment for dark matter axions. We propose experimental setups in which axionic interaction strengths in a Josephson junction environment can be tested, similar in nature to recent experiments that test for quantum entanglement of two coupled Josephson qubits. We point out that the parameter values relevant for early-universe axion cosmology are accessible with present day's achievements in nanotechnology. We work out how typical dark matter and dark energy signals would look like in a novel detector that exploits this effect.

  5. Averaged equations for Josephson junction series arrays with LRC load

    E-Print Network [OSTI]

    Kurt Wiesenfeld; James W. Swift

    1994-08-26T23:59:59.000Z

    We derive the averaged equations describing a series array of Josephson junctions shunted by a parallel inductor-resistor-capacitor load. We assume that the junctions have negligable capacitance ($\\beta = 0$), and derive averaged equations which turn out to be completely tractable: in particular the stability of both in-phase and splay states depends on a single parameter, $\\del$. We find an explicit expression for $\\delta$ in terms of the load parameters and the bias current. We recover (and refine) a common claim found in the technical literature, that the in-phase state is stable for inductive loads and unstable for capacitive loads.

  6. Testing axion physics in a Josephson junction environment

    E-Print Network [OSTI]

    Christian Beck

    2011-11-17T23:59:59.000Z

    We suggest that experiments based on Josephson junctions, SQUIDS, and coupled Josephson qubits can be used to construct a resonant environment for dark matter axions. We propose experimental setups in which axionic interaction strengths in a Josephson junction environment can be tested, similar in nature to recent experiments that test for quantum entanglement of two coupled Josephson qubits. We point out that the parameter values relevant for early-universe axion cosmology are accessible with present day's achievements in nanotechnology. We work out how typical dark matter and dark energy signals would look like in a novel detector that exploits this effect.

  7. Three-dimensional Josephson-junction arrays: Static magnetic response

    SciTech Connect (OSTI)

    De Luca, R.; Di Matteo, T. [INFM-Dipartimento di Fisica, Universita degli Studi di Salerno, I-84081 Baronissi (Salerno) (Italy)] [INFM-Dipartimento di Fisica, Universita degli Studi di Salerno, I-84081 Baronissi (Salerno) (Italy); Tuohimaa, A.; Paasi, J. [Laboratory of Electricity and Magnetism, Tampere University of Technology, FIN-33101 Tampere (Finland)] [Laboratory of Electricity and Magnetism, Tampere University of Technology, FIN-33101 Tampere (Finland)

    1998-01-01T23:59:59.000Z

    In this work we present a simple three-dimensional Josephson-junction array model: a cube with twelve junctions, one on each edge. The low-field magnetic response of the system is studied numerically for arbitrary directions of the applied field. In this model the magnetic energy of the circulating currents is taken into account by introducing an effective mutual inductance matrix. The lower threshold field for flux penetration is determined in a closed analytic form for field directions perpendicular to one cube side. {copyright} {ital 1998} {ital The American Physical Society}

  8. Noise in Bose Josephson junctions: Decoherence and phase relaxation

    SciTech Connect (OSTI)

    Ferrini, G.; Minguzzi, A.; Hekking, F. W. J. [Laboratoire de Physique et Modelisation des Milieux Condenses, Universite Joseph Fourier and CNRS, Boite Postale 166, F-38042 Grenoble (France); Spehner, D. [Laboratoire de Physique et Modelisation des Milieux Condenses, Universite Joseph Fourier and CNRS, Boite Postale 166, F-38042 Grenoble (France); Institut Fourier, Universite Joseph Fourier and CNRS, Boite Postale 74, F-38402 Saint Martin d'Heres (France)

    2010-09-15T23:59:59.000Z

    Squeezed states and macroscopic superpositions of coherent states have been predicted to be generated dynamically in Bose Josephson junctions. We solve exactly the quantum dynamics of such a junction in the presence of a classical noise coupled to the population-imbalance number operator (phase noise), accounting for, for example, the experimentally relevant fluctuations of the magnetic field. We calculate the correction to the decay of the visibility induced by the noise in the non-Markovian regime. Furthermore, we predict that such a noise induces an anomalous rate of decoherence among the components of the macroscopic superpositions, which is independent of the total number of atoms, leading to potential interferometric applications.

  9. Emission of terahertz waves from stacks of intrinsic Josephson junctions.

    SciTech Connect (OSTI)

    Gray, K. E.; Koshelev, A. E.; Kurter, C.; Kadowaki, K.; Yamamoto, T.; Minami, H.; Yamaguchi, H.; Tachiki, M.; Kwok, W.-K.; Welp, U.; Materials Science Division; Izmir Inst. of Tech.; Univ. Tsukuba; Univ. Tokyo

    2009-06-01T23:59:59.000Z

    By patterning mesoscopic crystals of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} (BSCCO) into electromagnetic resonators the oscillations of a large number of intrinsic Josephson junctions can be synchronized into a macroscopic coherent state accompanied by the emission of strong continuous wave THz-radiation. The temperature dependence of the emission is governed by the interplay of self-heating in the resonator and by re-trapping of intrinsic Josephson junctions which can yield a strongly non-monotonic temperature dependence of the emission power. Furthermore, proper shaping of the resonators yields THz-sources with voltage-tunable emission frequencies.

  10. Exact Quantum Dynamics of a Bosonic Josephson Junction

    SciTech Connect (OSTI)

    Sakmann, Kaspar; Streltsov, Alexej I.; Alon, Ofir E.; Cederbaum, Lorenz S. [Theoretische Chemie, Physikalisch-Chemisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany)

    2009-11-27T23:59:59.000Z

    The quantum dynamics of a one-dimensional bosonic Josephson junction is studied by solving the time-dependent many-boson Schroedinger equation numerically exactly. Already for weak interparticle interactions and on short time scales, the commonly employed mean-field and many-body methods are found to deviate substantially from the exact dynamics. The system exhibits rich many-body dynamics such as enhanced tunneling and a novel equilibration phenomenon of the junction depending on the interaction, which is attributed to a quick loss of coherence.

  11. Exact quantum dynamics of a bosonic Josephson junction

    E-Print Network [OSTI]

    Kaspar Sakmann; Alexej I. Streltsov; Ofir E. Alon; Lorenz S. Cederbaum

    2009-05-06T23:59:59.000Z

    The quantum dynamics of a one-dimensional bosonic Josephson junction is studied by solving the time-dependent many-boson Schr\\"odinger equation numerically exactly. Already for weak interparticle interactions and on short time scales, the commonly-employed mean-field and many-body methods are found to deviate substantially from the exact dynamics. The system exhibits rich many-body dynamics like enhanced tunneling and a novel equilibration phenomenon of the junction depending on the interaction, attributed to a quick loss of coherence.

  12. Free electron gas primary thermometer: The bipolar junction transistor

    SciTech Connect (OSTI)

    Mimila-Arroyo, J., E-mail: jmimila@cinvestav.mx [Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Dpto. de Ing. Eléctrica-SEES, Av. Instituto Politécnico Nacional No 2508, México D.F. CP 07360 (Mexico)

    2013-11-04T23:59:59.000Z

    The temperature of a bipolar transistor is extracted probing its carrier energy distribution through its collector current, obtained under appropriate polarization conditions, following a rigorous mathematical method. The obtained temperature is independent of the transistor physical properties as current gain, structure (Homo-junction or hetero-junction), and geometrical parameters, resulting to be a primary thermometer. This proposition has been tested using off the shelf silicon transistors at thermal equilibrium with water at its triple point, the transistor temperature values obtained involve an uncertainty of a few milli-Kelvin. This proposition has been successfully tested in the temperature range of 77–450?K.

  13. Estimating commuter rail demand to Kendall Square along the Grand Junction Corridor

    E-Print Network [OSTI]

    Bockelie, Adam

    2012-01-01T23:59:59.000Z

    Since acquiring the Grand Junction Railroad in June 2010 from CSX, the Massachusetts Bay Transit Authority (MBTA) has explored the possibility of using the line for commuter rail service. In addition the Grand Junction ...

  14. Interaction of Josephson Junction and Distant Vortex in Narrow Thin-Film Superconducting Strips

    SciTech Connect (OSTI)

    Kogan, V. G. [Ames Laboratory; Mints, R. G. [Tel Aviv University

    2014-01-31T23:59:59.000Z

    The phase difference between the banks of an edge-type planar Josephson junction crossing the narrow thin-film strip depends on wether or not vortices are present in the junction banks. For a vortex close to the junction this effect has been seen by Golod, Rydh, and Krasnov [Phys. Rev. Lett. 104, 227003 (2010)], who showed that the vortex may turn the junction into ? type. It is shown here that even if the vortex is far away from the junction, it still changes the 0 junction to a ? junction when situated close to the strip edges. Within the approximation used, the effect is independent of the vortex-junction separation, a manifestation of the topology of the vortex phase which extends to macroscopic distances of superconducting coherence.

  15. E-Print Network 3.0 - alter tight junction Sample Search Results

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

    if the read-out junction is in the underdamped phase... cheerful atmosphere in the Josephson junctions ii tel-00586075,version1-14Apr2011 12;iii group and thank......

  16. E-Print Network 3.0 - altered tight junction Sample Search Results

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

    if the read-out junction is in the underdamped phase... cheerful atmosphere in the Josephson junctions ii tel-00586075,version1-14Apr2011 12;iii group and thank......

  17. Photo of the Week: An Express Train to Crescent Junction | Department...

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

    An Express Train to Crescent Junction Photo of the Week: An Express Train to Crescent Junction January 4, 2013 - 1:53pm Addthis In the 1950s, one of the largest uranium deposits in...

  18. Optimized Triple-Junction Solar Cells Using Inverted Metamorphic Approach (Presentation)

    SciTech Connect (OSTI)

    Geisz, J. F.

    2008-11-01T23:59:59.000Z

    Record efficiencies with triple-junction inverted metamorphic designs, modeling useful to optimize, and consider operating conditions before choosing design.

  19. Optical and carrier transport properties of graphene oxide based crystalline-Si/organic Schottky junction solar cells

    SciTech Connect (OSTI)

    Khatri, I.; Tang, Z.; Hiate, T.; Liu, Q.; Ishikawa, R.; Ueno, K.; Shirai, H. [Graduate School of Science and Engineering, Saitama University, Saitama 338-8570 (Japan)

    2013-12-21T23:59:59.000Z

    We investigated the graphene oxide (GO) based n-type crystalline silicon (c-Si)/conductive poly(ethylene dioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) Schottky junction devices with optical characterization and carrier transport measurement techniques. The optical transmittance in the UV region decreased markedly for the films with increasing the concentration of GO whereas it increased markedly in the visible-infrared regions. Spectroscopic ellipsometry revealed that the ordinary and extraordinary index of refraction increased with increasing the concentration of GO. The hole mobility also increased from 1.14 for pristine film to 1.85 cm{sup 2}/V s for the 12–15?wt. % GO modified film with no significant increases of carrier concentration. The highest conductivity was found for a 15?wt. % GO modified PEDOT:PSS film: the c-Si/PEDOT:PSS:GO device using this sample exhibited a relatively high power conversion efficiency of 11.04%. In addition, the insertion of a 2–3?nm-thick GO thin layer at the c-Si/PEDOT:PSS interface suppressed the carrier recombination efficiency of dark electron and photo-generated hole at the anode, resulting in the increased photovoltaic performance. This study indicates that the GO can be good candidates for hole transporting layer of c-Si/PEDOT:PSS Schottky junction solar cell.

  20. Boron-layer silicon photodiodes for high-efficiency low-energy electron detection Agata Sakic a,

    E-Print Network [OSTI]

    Technische Universiteit Delft

    Boron-layer silicon photodiodes for high-efficiency low-energy electron detection Agata Sakic´ a photodiodes Electron detection Low-energy electrons Boron deposition Ultrashallow junctions Responsivity Electron signal gain Electron irradiation Dark current degradation a b s t r a c t Silicon photodiodes

  1. Nanomechanical-resonator-induced synchronization in Josephson junction arrays B. R. Trees* and S. Natu

    E-Print Network [OSTI]

    Stroud, David

    , and an interaction energy due to the piezo- electric effect between the NEM and the junctions. Phase lockingNanomechanical-resonator-induced synchronization in Josephson junction arrays B. R. Trees* and S that includes the following effects: the charging and Josephson energies of the junctions, dissipation

  2. Fluxon Dynamics and Radiation Emission in Twofold Long Josephson Junction Stacks

    E-Print Network [OSTI]

    Leonardo, Degiorgi

    Fluxon Dynamics and Radiation Emission in Twofold Long Josephson Junction Stacks Andreas Wallraff¨ulich (KFA) January 27, 1997 #12;#12; Contents Introduction 1 1 Basic properties of Josephson junctions 5 2 Electrodynamics in long Josephson junctions 11 3 Radiation emission by stacked flux­flow oscillators 29 1

  3. Collapse of superconductivity in a hybrid tin-graphene Josephson junction array

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Collapse of superconductivity in a hybrid tin-graphene Josephson junction array Zheng Han1 of the Josephson junction array into a zero-temperature metallic state. The suppression of proximity, models involving specific types of Josephson junction arrays in which superconducting disks are coupled

  4. Resonant plasmon scattering by discrete breathers in Josephson junction ladders A. E. Miroshnichenko,1

    E-Print Network [OSTI]

    Flach, Sergej

    Resonant plasmon scattering by discrete breathers in Josephson junction ladders A. E scattering by discrete breathers in Josephson junction ladders. DOI: 10.1103/PhysRevB.71.174306 PACS number Josephson junction systems,2 coupled nonlinear optical waveguides,3 lattice vi- brations in crystals,4

  5. PHYSICAL REVIEW B 87, 144301 (2013) Parametric amplification in Josephson junction embedded transmission lines

    E-Print Network [OSTI]

    Friedland, Lazar

    PHYSICAL REVIEW B 87, 144301 (2013) Parametric amplification in Josephson junction embedded (Josephson junctions) is studied theoretically. A continuous nonlinear wave equation describing the dynamics ranging from 1­10 MHz.9­13 These amplifiers, however, comprise a single Josephson junction or an array

  6. Andreev-level spectroscopy and Josephson-current switching in a three-terminal Josephson junction

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Andreev-level spectroscopy and Josephson-current switching in a three-terminal Josephson junction H held in thermodynamic equilibrium with the two superconducting contacts of a Josephson junction. When levels. The additional normal-metal probe coupled to the Josephson junction, shown in Fig. 1, models

  7. Resonant plasmon scattering by discrete breathers in Josephson junction ladders A. E. Miroshnichenko,1

    E-Print Network [OSTI]

    Resonant plasmon scattering by discrete breathers in Josephson junction ladders A. E in Josephson junction ladders. We predict the existence of Fano resonances, and find them by computing in the plasmon scattering by discrete breathers in Josephson junction ladders. DOI: 10.1103/PhysRevB.71

  8. Pinned fluxons in a Josephson junction with a finite-length inhomogeneity

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Pinned fluxons in a Josephson junction with a finite-length inhomogeneity Gianne Derks , Arjen Doelman Christopher J.K. Knight§ , Hadi Susanto¶ July 5, 2011 Abstract We consider a Josephson junction as limits of our results on microresonators. Keywords: Josephson junction, inhomogeneous sine

  9. Quantum Coherence in a Superfluid Josephson Junction Supradeep Narayana and Yuki Sato

    E-Print Network [OSTI]

    Sato, Yuki

    Quantum Coherence in a Superfluid Josephson Junction Supradeep Narayana and Yuki Sato The Rowland in which we take an array of nanoscale apertures that form a superfluid 4He Josephson junction and apply Josephson junctions as well as phase coherence among the superfluid aperture array are discussed. DOI: 10

  10. Pinned fluxons in a Josephson junction with a finite-length inhomogeneity

    E-Print Network [OSTI]

    Doelman, Arjen

    Pinned fluxons in a Josephson junction with a finite-length inhomogeneity Gianne Derks , Arjen as limits of our results on microresonators. Keywords: Josephson junction, inhomogeneous sine Josephson junction tt = xx - D sin() + - t, (1) where x and t are the spatial and temporal variable

  11. Three-dimensional Josephson junction networks with coupling inhomogeneities in magnetic fields

    E-Print Network [OSTI]

    Di Matteo, Tiziana

    Three-dimensional Josephson junction networks with coupling inhomogeneities in magnetic fields A on the static magnetic response of a three-dimensional 8 · 8 · 8 network of Josephson junctions is studied of one-dimensional and two-dimensional Josephson junction networks (1D, 2D-JJNs) has been extensively

  12. Direct Observation of Dynamical Bifurcation in a Superfluid Josephson Junction Supradeep Narayana and Yuki Sato

    E-Print Network [OSTI]

    Sato, Yuki

    Direct Observation of Dynamical Bifurcation in a Superfluid Josephson Junction Supradeep Narayana Josephson junction. We excite the superfluid plasma resonance into a nonlinear regime by driving below.205302 PACS numbers: 67.25.dg, 07.60.Ly, 47.20.Ky, 85.25.Cp A superfluid Josephson junction is formed

  13. Josephson-junction arrays with long-range interactions J. Kent Harbaugh and D. Stroud

    E-Print Network [OSTI]

    Stroud, David

    Josephson-junction arrays with long-range interactions J. Kent Harbaugh and D. Stroud Department-voltage (IV) characteristics of a Josephson-junction array with long-range inter- actions. The array consists of two sets of equally spaced parallel superconducting wires placed at right angles. A Josephson junction

  14. Quantum phase transitions and persistent currents in Josephson-junction ladders Minchul Lee

    E-Print Network [OSTI]

    Choi, Mahn-Soo

    Quantum phase transitions and persistent currents in Josephson-junction ladders Minchul Lee- dimensional Josephson-junction arrays. We will focus particularly on the roles of excitonlike pairs.40.Db, 73.23.Hk I. INTRODUCTION Systems of Josephson junctions between small supercon- ducting grains

  15. Phase qubits fabricated with trilayer junctions M. Weides1,2

    E-Print Network [OSTI]

    Martinis, John M.

    Josephson junction geometry with minimal volume of lossy isolation dielectric, being suitable for higher) spectroscopy and time-domain measurements of the qubit. By systematically replacing only the Josephson junction element, and, ideally, develop low-loss Josephson junctions for superconducting qubits and improve our

  16. Depinning of kinks in a Josephson-junction ratchet array E. Trias,1

    E-Print Network [OSTI]

    Orlando, Terry P.

    Depinning of kinks in a Josephson-junction ratchet array E. Tri´as,1 J. J. Mazo,1,2 F. Falo,2 and T kinks in a ratchet potential using a fabricated circular array of Josephson junctions. Our ratchet . Josephson junctions are solid state realizations of a simple pendulum. By coupling them, it is possible

  17. Switching current measurements of large area Josephson tunnel junctions A. Wallraff,a)

    E-Print Network [OSTI]

    Wallraff, Andreas

    the potential. This corresponds to a transition of the Josephson junction from a superconducting zero the system is coupled. Thermal activation TA in a current-biased Josephson junction has been studied both damping.11,12 At low temperatures the quantum mechanical properties of Josephson junctions have been

  18. DESIGN APPROACHES AND MATERIALS PROCESSES FOR ULTRAHIGH EFFICIENCY LATTICE MISMATCHED MULTI-JUNCTION SOLAR CELLS

    E-Print Network [OSTI]

    Atwater, Harry

    -JUNCTION SOLAR CELLS Melissa J. Griggs 1 , Daniel C. Law 2 , Richard R. King 2 , Arthur C. Ackerman 3 , James M heterostructures grown in a multi-junction solar cell-like structure by MOCVD. Initial solar cell data are also of the minority carrier lifetime. INTRODUCTION High efficiency triple junction solar cells have recently been

  19. Higher-order effects on Shapiro steps in Josephson junctions Kim O" . Rasmussen and Vadim Zharnitsky*

    E-Print Network [OSTI]

    Zharnitsky, Vadim

    Higher-order effects on Shapiro steps in Josephson junctions Kim O" . Rasmussen and Vadim is that the pendulum equation is the most widely used model for super- conducting Josephson junctions.1,8 Particularly Josephson junction, where phase-locking of the voltage response to an ac current can occur in certain

  20. Josephson Junction with a Magnetic-Field Tunable Ground State E. Goldobin,1

    E-Print Network [OSTI]

    Mints, Roman G.

    Josephson Junction with a Magnetic-Field Tunable Ground State E. Goldobin,1 D. Koelle,1 R. Kleiner; published 21 November 2011) We consider an asymmetric 0- Josephson junction consisting of 0 and regions.25.Cp Josephson junctions (JJs) with a phase shift of in the ground state [1] attracted a lot

  1. SIS Josephson junction with a correlated insulator below its SI transition

    E-Print Network [OSTI]

    Stroud, David

    S­I­S Josephson junction with a correlated insulator below its S­I transition C.D. Porter Accepted 31 December 2013 Available online 9 January 2014 Keywords: Josephson junction array Superconductor, with a correlated insulating region, can be viewed as a single effective Josephson junction. � 2014 Elsevier B

  2. Josephson junction in a thin film V. G. Kogan, V. V. Dobrovitski, and J. R. Clem

    E-Print Network [OSTI]

    Mints, Roman G.

    Josephson junction in a thin film V. G. Kogan, V. V. Dobrovitski, and J. R. Clem Ames Laboratory The phase difference (y) for a vortex at a line Josephson junction in a thin film attenuates at large was normal to the film faces unlike traditional thin-film large- area Josephson junctions in which

  3. Quantum Monte Carlo study of a disordered 2D Josephson junction array

    E-Print Network [OSTI]

    Stroud, David

    Quantum Monte Carlo study of a disordered 2D Josephson junction array W.A. Al-Saidi *, D. Stroud reserved. PACS: 74.25.Dw; 05.30.Jp; 85.25.Cp Keywords: Josephson junctions; Quantum Monte Carlo; Disorder 1. Introduction A Josephson junction array (JJA) consists of a collection of superconducting islands connected

  4. The chaotic oscillations of a Josephson junction with external magnetic field

    SciTech Connect (OSTI)

    Ma, J.G.; Wolff, I. [Duisburg Univ. (Germany). Dept. of Electrical Engineering

    1996-05-01T23:59:59.000Z

    Using the Melnikov Method the oscillation of a single Josephson junction with external magnetic field and DC bias is analyzed. Under the external magnetic field the junction can operate in chaos even if there is no bias. The numerical results show that in dependence on some parameters the Josephson junction with external magnetic field will go from stable periodic states to chaotic states.

  5. Washing out of the 0-transition in Josephson junctions R. Avriller1

    E-Print Network [OSTI]

    Boyer, Edmond

    Washing out of the 0- transition in Josephson junctions R. Avriller1 and F. Pistolesi1 1 Univ: July 21, 2014) We consider a Josephson junction formed by a quantum dot connected to two bulk numbers: 73.23.-b, 74.25.F-, 74.50.+r, 74.45.+c Introduction.-- The Josephson junction is a fun- damental

  6. Tunneling Qubit Operation on a Protected Josephson Junction Array

    E-Print Network [OSTI]

    Zhi Yin; Sheng-Wen Li; Yi-Xin Chen

    2010-01-29T23:59:59.000Z

    We discuss a protected quantum computation process based on a hexagon Josephson junction array. Qubits are encoded in the punctured array, which is topologically protected. The degeneracy is related to the number of holes. The topological degeneracy is lightly shifted by tuning the flux through specific hexagons. We also show how to perform single qubit operation and basic quantum gate operations in this system.

  7. Topological order in Josephson junction ladders with Mobius boundary conditions

    E-Print Network [OSTI]

    G. Cristofano; V. Marotta; A. Naddeo

    2005-03-22T23:59:59.000Z

    We propose a CFT description for a closed one-dimensional fully frustrated ladder of quantum Josephson junctions with Mobius boundary conditions, in particular we show how such a system can develop topological order. Such a property is crucial for its implementation as a "protected" solid state qubit.

  8. Particle pulses from superconducting aluminum tunnel junction detectors

    SciTech Connect (OSTI)

    Stricker, D.A.; Bing, D.D.; Bland, R.W.; Dickson, S.C.; Dignan, T.; Johnson, R.T.; Lockhart, J.M.; Laws, K.; Simon, M.W.; Watson, R. (San Francisco State Univ., Physics and Astronomy Dept. San Francisco, CA (US))

    1991-03-01T23:59:59.000Z

    Superconducting aluminum tunnel junctions have been developed for use as particle detectors. This paper presents results on static characteristics of these devices. We also present results from tests of these detectors with 6-keV X-rays. An extrapolation of the properties of these detectors to one suitable for dark-matter detectors is discussed.

  9. Determination of the current density distribution in Josephson junctions.

    SciTech Connect (OSTI)

    Carmody, M; Landree, E.; Marks, L. D.; Merkle, K. L.; Northwestern Univ.

    1999-01-01T23:59:59.000Z

    A technique is described for recovering the missing phase information for a set of critical current measurements as a function of an applied magnetic field I{sub c}(B). In many cases the current density j(x) across the boundary for a Josephson junction can be determined.

  10. Distinguished solutions for discontinuous signature change with weak junction conditions

    E-Print Network [OSTI]

    M. Kriele

    1996-10-10T23:59:59.000Z

    We consider discontinuous signature change with the weak junction condition favoured by Ellis et. al. (1992). We impose certain regularity conditions and investigate the space of solutions (considered as one-parameter families of three-dimensional Riemannian manifolds) for dust and scalar field models.

  11. Aluminum tunnel junction detector operation in an adiabatic demagnetization refrigerator

    SciTech Connect (OSTI)

    Labov, S.; Silver, E.; Le Gros, M. (Lawrence Livermore National Lab., CA (United States)); Bland, R.W.; Dickson, S.C.; Dignan, T.G.; Laws, K.; Johnson, R.T.; Simon, M.W.; Stricker, D.A.; Watson, R.M. (San Francisco State Univ., CA (United States)); Madden, N.; Landis, D. (Lawrence Berkeley Lab., CA (United States))

    1992-01-30T23:59:59.000Z

    Superconducting tunnel junction detectors are being developed as both particle and X-ray detectors. Aluminum junctions are desirable for detectors because of their strong native oxide barriers, and because the small energy gap of aluminum is a good match to ballistic phonons generated by particle interactions in single crystals of silicon or other low acoustic-loss insulating crystals. Aluminum tunnel junction detectors must be operated near 0.1 T{sub C} which is 110 mK for aluminum. To operate detectors at these temperatures, we have developed adiabatic demagnetization refrigerators (ADRs) for the laboratory and prototype ADRs for space based operation. These cryogenic systems are simpler, more convenient and more portable than most dilution refrigerators. We have demonstrated that the magnetic field of the ADR need not compromise the performance of aluminum tunnel junctions. We have recently initiated a program to develop superconducting tunnel junctions (STJs) as high resolution X-ray detectors and low energy threshold particle detectors. This complements our existing program in which we are developing high resolution X-ray microcalorimeter detectors. One of our goals for both of these cryogenic detector development efforts is to observe X-ray emission from cosmic sources. This requires a refrigeration system that can operate under zero gravity space flight conditions. For the microcalorimeter project, temperatures of 100 mK and below are required to sufficiently reduce the heat capacity of the device. We have therefore developed an adiabatic demagnetization refrigerator (ADR) system which can be configured for space flight.

  12. Conformation of Adjacent Self-expanding Stents: A Cross-Sectional In Vitro Study

    SciTech Connect (OSTI)

    Hughes, Marion; Forauer, Andrew R. [University of Michigan Medical Center, Section of Vascular and Interventional Radiology (United States)], E-mail: andrew.r.forauer@hitchcock.org; Lindh, Mats [University Hospital MAS, Radiology Department (Sweden); Cwikiel, Wojciech [University of Michigan Medical Center, Section of Vascular and Interventional Radiology (United States)

    2006-04-15T23:59:59.000Z

    We examined the proximal conformation of three commonly used self-expanding stents when the stents were deployed adjacent to one another in a tubular model, simulating a 'kissing' stent technique. The stent pairs were evaluated by computed tomogrphy to determine the cross-sectional area excluded by the stents within the model. The mean areas associated with each stent pair were compared and significance evaluated by a t-test. A statistically significant difference was found when the area excluded by adjacent Wallstents was compared with both the Luminexx and SMART stents (p < 0.001 and p < 0.002, respectively). The difference in the area excluded and differences in conformation might play a role in the lower patencies that have been observed in 'kissing' stent series.

  13. Quantum efficiency of a microwave photon detector based on a current-biased Josephson junction

    E-Print Network [OSTI]

    Poudel, Amrit; Vavilov, Maxim G

    2012-01-01T23:59:59.000Z

    We analyze the quantum efficiency of a microwave photon detector based on a current-biased Josephson junction. We consider the Jaynes-Cummings Hamiltonian to describe coupling between the photon field and the junction. We then take into account coupling of the junction and the resonator to the environment. We solve the equation of motion of the density matrix of the resonator-junction system to compute the quantum efficiency of the detector as a function of detection time, bias current, and energy relaxation time. Our results indicate that junctions with modest coherence properties can provide efficient detection of single microwave photons, with quantum efficiency in excess of 80%.

  14. Study of junction flows in louvered fin round tube heat exchangers using the dye injection technique

    SciTech Connect (OSTI)

    Huisseune, H.; Willockx, A.; De Paepe, M. [Department of Flow, Heat and Combustion Mechanics, Ghent University, Sint-Pietersnieuwstraat 41, 9000 Gent (Belgium); T'Joen, C. [Department of Flow, Heat and Combustion Mechanics, Ghent University, Sint-Pietersnieuwstraat 41, 9000 Gent (Belgium); Department Radiation, Radionuclides and Reactors, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); De Jaeger, P. [Department of Flow, Heat and Combustion Mechanics, Ghent University, Sint-Pietersnieuwstraat 41, 9000 Gent (Belgium); NV Bekaert SA, Bekaertstraat 2, 8550 Zwevegem (Belgium)

    2010-11-15T23:59:59.000Z

    Detailed studies of junction flows in heat exchangers with an interrupted fin design are rare. However, understanding these flow structures is important for design and optimization purposes, because the thermal hydraulic performance of heat exchangers is strongly related to the flow behaviour. In this study flow visualization experiments were performed in six scaled-up models of a louvered fin round tube heat exchanger. The models have three tube rows in a staggered layout and differ only in their fin spacing and louver angle. A water tunnel was designed and built and the flow visualizations were carried out using dye injection. At low Reynolds numbers the streakline follows the tube contours, while at higher Reynolds numbers a horseshoe vortex is developed ahead of the tubes. The two resulting streamwise vortex legs are destroyed by the downstream louvers (i.e. downstream the turnaround louver), especially at higher Reynolds numbers, smaller fin pitches and larger louver angles. Increasing the fin spacing results in a larger and stronger horseshoe vortex. This illustrates that a reduction of the fin spacing results in a dissipation of vortical motion by mechanical blockage and skin friction. Furthermore it was observed that the vortex strength and number of vortices in the second tube row is larger than in the first tube row. This is due to the thicker boundary layer in the second tube row, and the flow deflection, which is typical for louvered fin heat exchangers. Visualizations at the tube-louver junction showed that in the transition part between the angled louver and the flat landing a vortex is present underneath the louver surface which propagates towards the angled louver. (author)

  15. Mutual synchronization of two stacks of intrinsic Josephson junctions in cuprate superconductors

    SciTech Connect (OSTI)

    Lin, Shi-Zeng [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-05-07T23:59:59.000Z

    Certain high-T{sub c} cuprate superconductors, which naturally realize a stack of Josephson junctions, thus can be used to generate electromagnetic waves in the terahertz region. A plate-like single crystal with 10{sup 4} junctions without cavity resonance was proposed to achieve strong radiation. For this purpose, it is required to synchronize the Josephson plasma oscillation in all junctions. In this work, we propose to use two stacks of junctions shunted in parallel to achieve synchronization. The two stacks are mutually synchronized in the whole IV curve, and there is a phase shift between the plasma oscillation in the two stacks. The phase shift is nonzero when the number of junctions in different stacks is the same, while it can be arbitrary when the number of junctions is different. This phase shift can be tuned continuously by applying a magnetic field when all the junctions are connected by superconducting wires.

  16. Quantum Dissociation of a Vortex-Antivortex Pair in a Long Josephson Junction M.V. Fistul,1

    E-Print Network [OSTI]

    Wallraff, Andreas

    Quantum Dissociation of a Vortex-Antivortex Pair in a Long Josephson Junction M.V. Fistul,1 A VAV pair manifests itself in a switching of the Josephson junction from the superconducting biased single Josephson junctions (JJs), various SQUIDs, and small Josephson junction arrays, contain

  17. PHYSICAL REVIEW B 87, 214511 (2013) Linewidth of the electromagnetic radiation from Josephson junctions near cavity resonances

    E-Print Network [OSTI]

    Alexei, Koshelev

    emission from intrinsic Josephson junctions in high-Tc cuprate superconductors has been detected recently for a single Josephson junction nor for a stack of the intrinsic Josephson junctions realized in cuprateRevB.87.214511 PACS number(s): 74.50.+r, 74.25.Gz, 85.25.Cp In a Josephson junction (JJ) biased by a dc

  18. Layered plasma polymer composite membranes

    DOE Patents [OSTI]

    Babcock, W.C.

    1994-10-11T23:59:59.000Z

    Layered plasma polymer composite fluid separation membranes are disclosed, which comprise alternating selective and permeable layers for a total of at least 2n layers, where n is [>=]2 and is the number of selective layers. 2 figs.

  19. Strain designed Josephson $?$ junction qubits with topological insulators

    E-Print Network [OSTI]

    Colin Benjamin

    2015-04-09T23:59:59.000Z

    A Josephson qubit is designed via the application of a tensile strain to a topological insulator surface sandwiched between two s-wave superconductors. The strain applied leads to a shift in the Dirac point without changing the pre-existing conducting states, on the surface of a topological insulator. Strain applied can be tuned to form a $\\pi$ junction in such a structure. Combining two such junctions in a ring architecture leads to the ground state of the ring being in doubly degenerate state- the "0" and "1" states of a qubit. A qubit designed this way is quite easily controlled via the tunable strain applied. We report on the conditions necessary to design such a qubit. Finally the operating time of a single qubit phase gate is derived.

  20. Transient Dynamics in Molecular Junctions: Coherent Bichromophoric Molecular Electron Pumps

    E-Print Network [OSTI]

    Roie Volkovich; Uri Peskin

    2010-12-01T23:59:59.000Z

    The possibility of using single molecule junctions as electron pumps for energy conversion and storage is considered. It is argued that the small dimensions of these systems enable to make use of unique intra-molecular quantum coherences in order to pump electrons between two leads and to overcome relaxation processes which tend to suppress the pumping efficiency. In particular, we demonstrate that a selective transient excitation of one chromophore in a bi-chromophoric donor-bridge-acceptor molecular junction model yields currents which transfer charge (electron and holes) unevenly to the two leads in the absence of a bias potential. The utility of this mechanism for charge pumping in steady state conditions is proposed.

  1. Chiral Edge Currents in a Holographic Josephson Junction

    E-Print Network [OSTI]

    Moshe Rozali; Alexandre Vincart-Emard

    2013-11-28T23:59:59.000Z

    We discuss the Josephson effect and the appearance of dissipationless edge currents in a holographic Josephson junction configuration involving a chiral, time-reversal breaking, superconductor in 2+1 dimensions. Such a superconductor is expected to be topological, thereby supporting topologically protected gapless Majorana-Weyl edge modes. Such modes manifest themselves in chiral dissipationless edge currents, which we exhibit and investigate in the context of our construction. The physics of the Josephson current itself, though expected to be unconventional in some non-equilibrium settings, is shown to be conventional in our setup which takes place in thermal equilibrium. We comment on various ways in which the expected Majorana nature of the edge excitations, and relatedly the unconventional nature of topological Josephson junctions, can be verified in the holographic context.

  2. Resistance of Josephson Junction Arrays at Low Temperatures

    E-Print Network [OSTI]

    L. B. Ioffe; B. N. Narozhny

    1998-07-25T23:59:59.000Z

    We study motion of vortices in arrays of Josephson junctions at zero temperature where it is controlled by quantum tunneling from one plaquette to another. The tunneling process is characterized by a finite time and can be slow compared to the superconducting gap (so that $\\tau \\Delta >> 1$). The dissipation which accompanies this process arises from rare processes when a vortex excites a quasiparticle above the gap while tunneling through a single junction. We find that the dissipation is significant even in the case $\\tau \\Delta >> 1$, in particular it is not exponentially small in this parameter. We use the calculated energy dissipation for the single vortex jump to estimate the physical resistance of the whole array.

  3. Josephson Junctions and AdS/CFT Networks

    E-Print Network [OSTI]

    Kiritsis, Elias

    2011-01-01T23:59:59.000Z

    We propose a new holographic model of Josephson junctions (and networks thereof) based on designer multi-gravity, namely multi-(super)gravity theories on products of distinct asymptotically AdS spacetimes coupled by mixed boundary conditions. We present a simple model of a Josephson junction (JJ) that reproduces trivially the well-known current-phase sine relation of JJs. In one-dimensional chains of holographic superconductors we find that the Cooper-pair condensates are described by a discretized Schrodinger-type equation. Such non-integrable equations, which have been studied extensively in the past in condensed matter and optics applications, are known to exhibit complex behavior that includes periodic and quasiperiodic solutions, chaotic dynamics, soliton and kink solutions. In our setup these solutions translate to holographic configurations of strongly-coupled superconductors in networks with weak site-to-site interactions that exhibit interesting patterns of modulated superconductivity. In a continuum...

  4. Topological p-n junctions in helical edge states

    E-Print Network [OSTI]

    Disha Wadhawan; Poonam Mehta; Sourin Das

    2014-11-24T23:59:59.000Z

    Quantum spin Hall effect is endowed with topologically protected edge modes with gapless Dirac spectrum. Applying a magnetic field locally along the edge leads to a gapped edge spectrum with opposite parity for winding of spin texture for conduction and valence band. Using Pancharatnam's prescription for geometric phase it is shown that mismatch of this parity across a p-n junction, which could be engineered into the edge by electrical gate induced doping, leads to a phase dependence in the two-terminal conductance which is purely topological (0 or $\\pi$). This fact results in a ${\\mathbb{Z}}_2$ classification of such junctions with an associated duality. Current asymmetry measurements which are shown to be robust against electron-electron interactions are proposed to infer this topology.

  5. Chiral Edge Currents in a Holographic Josephson Junction

    E-Print Network [OSTI]

    Rozali, Moshe

    2013-01-01T23:59:59.000Z

    We discuss the Josephson effect and the appearance of dissipationless edge currents in a holographic Josephson junction configuration involving a chiral, time-reversal breaking, superconductor in 2+1 dimensions. Such a superconductor is expected to be topological, thereby supporting topologically protected gapless Majorana-Weyl edge modes. Such modes manifest themselves in chiral dissipationless edge currents, which we exhibit and investigate in the context of our construction. The physics of the Josephson current itself, though expected to be unconventional in some non-equilibrium settings, is shown to be conventional in our setup which takes place in thermal equilibrium. We comment on various ways in which the expected Majorana nature of the edge excitations, and relatedly the unconventional nature of topological Josephson junctions, can be verified in the holographic context.

  6. Layered Cathode Materials

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

    Layered Cathode Materials presented by Michael Thackeray Chemical Sciences and Engineering Division, Argonne Annual Merit Review DOE Vehicle Technologies Program Washington, D.C....

  7. United States Department of Energy, Grand Junction Office

    SciTech Connect (OSTI)

    Not Available

    1980-01-01T23:59:59.000Z

    The Grand Junction Office (GJO), US Department of Energy (DOE), develops and administers programs for evaluating domestic uranium resources and the production capability of industry; for developing resource planning information for DOE; and for advancing geologic and geophysical exploration concepts and techniques. In addition, GJO administers the leasing of mineral lands under DOE control, and carries out activities relating to the environmental aspects of uranium mining and milling, including remedial programs. The Office is staffed by administrative and technical program-management personnel. Bendix Field Engineering Corporation (Bendix) is the DOE operating contractor at the Grand Junction, Colorado, Government-owned/contractor-operated (GOCO) facility. The technical staffs of both GJO and Bendix are primarily geoscience-oriented. Specifically during 1980, uranium resource assessment on 135 National Topographic Map Series (NTMS) quadrangles was completed, along with other specific studies, to yield October 1980 national resource estimates. In addition, updated uranium supply analysis and production capability projections were completed. Another key aspect of this successful program was the development of improved geophysical and geochemical equipment and techniques in support of uranium resource assessment. Much of the hardware and know-how developed was turned over to the public and to the uranium industry at large for application to uranium exploration and the assessment of uranium company resources. The Grand Junction Office also participated actively during 1980 in international cooperative research on uranium exploration techniques and on the geology of uranium deposits.

  8. Emission of Microwave Photon Pairs by a Tunnel Junction

    E-Print Network [OSTI]

    Jean-Charles Forgues; Christian Lupien; Bertrand Reulet

    2014-03-21T23:59:59.000Z

    Generation and control of non-classical electromagnetic fields is of crucial importance for quantum information physics. While usual methods for the production of such fields rely on a non-linearity (of a crystal, a Josephson junction, etc.), a recent experiment performed on a normal conductor, a tunnel junction under microwave irradiation, has unveiled an alternative: the use of electron shot noise in a quantum conductor\\cite{PAN_squeezing}. Here we show that such a device can emit \\emph{pairs of microwave photons} of different frequencies with a rate as high as that of superconducting Josephson junctions\\cite{Flurin}. This results in intensity fluctuations of the photon field at two different frequencies being correlated below the photon shot noise,i.e. two-mode amplitude squeezing. Our experiment constitutes a fundamental step towards the understanding of electronic noise in terms of quantum optics, and shows that even a normal conductor could be used as a resource for quantum information processing.

  9. Effects of the amorphous oxide intergranular layer structure and bonding on the fracture toughness of a high purity silicon nitride

    SciTech Connect (OSTI)

    Ziegler, A.; Kisielowski, C.; Hoffmann, M.J.; Ritchie, R.O.

    2002-11-18T23:59:59.000Z

    The microstructural evolution and structural characteristics and transitions in the thin grain-boundary oxide films in a silicon nitride ceramic, specifically between two adjacent grains and not the triple junctions, are investigated to find their effect on the macroscopic fracture properties. It is found that by heat treating a model Si3N4-2wt percent Y2O3 ceramic for {approx}200 hr at 1400 degrees C in air, the fracture toughness can be increased by {approx}100 percent, coincident with a change in fracture mechanism from transgranular to intergranular.

  10. Literature and data review for the surface-water pathway: Columbia River and adjacent coastal areas

    SciTech Connect (OSTI)

    Walters, W.H.; Dirkes, R.L.; Napier, B.A.

    1992-04-01T23:59:59.000Z

    As part of the Hanford Environmental Dose Reconstruction Project, Pacific Northwest Laboratory reviewed literature and data on radionuclide concentrations and distribution in the water, sediment, and biota of the Columbia River and adjacent coastal areas. Over 600 documents were reviewed including Hanford reports, reports by offsite agencies, journal articles, and graduate theses. Certain radionuclide concentration data were used in preliminary estimates of individual dose for the 1964--1966 time period. This report summarizes the literature and database review and the results of the preliminary dose estimates.

  11. The economic effects of elevated and depressed freeways on adjacent property owners

    E-Print Network [OSTI]

    Scurry, Floyd David

    1995-01-01T23:59:59.000Z

    ABSTRACT The Economic EfFects of Elevated and Depressed Freeways on The Adjacent Property Owners. (May 1995) Floyd David Sentry, B. S. , Texas AkM University Chair of Advisory Committee: Dr. Daniel B. Fambro An econonuc assessment of a comnunity... 322, 095 283, 680 283, 680 260, 040 3, 327, 330 $5, 005, 770 Net Effect of Highway on Property Values $4, 275 139, 635 185, 310 262, 145 254, 800 271, 680 257, 840 3, 327, 330 $4, 703, 095 23 The resale of homes at all levels showed...

  12. Surface plasmon dispersion engineering via double-metallic AU/AG layers for nitride light-emitting diodes

    DOE Patents [OSTI]

    Tansu, Nelson; Zhao, Hongping; Zhang, Jing; Liu, Guangyu

    2014-04-01T23:59:59.000Z

    A double-metallic deposition process is used whereby adjacent layers of different metals are deposited on a substrate. The surface plasmon frequency of a base layer of a first metal is tuned by the surface plasmon frequency of a second layer of a second metal formed thereon. The amount of tuning is dependent upon the thickness of the metallic layers, and thus tuning can be achieved by varying the thicknesses of one or both of the metallic layers. In a preferred embodiment directed to enhanced LED technology in the green spectrum regime, a double-metallic Au/Ag layer comprising a base layer of gold (Au) followed by a second layer of silver (Ag) formed thereon is deposited on top of InGaN/GaN quantum wells (QWs) on a sapphire/GaN substrate.

  13. Determination of HEat Capacity of Yucca Mountain Strtigraphic Layers

    SciTech Connect (OSTI)

    T. Hadgu; C. Lum; J.E. Bean

    2006-06-20T23:59:59.000Z

    The heat generated from the radioactive waste to be placed in the proposed geologic repository at Yucca Mountain, Nevada, will affect the thermal-hydrology of the Yucca Mountain stratigraphic layers. In order to assess the effect of the movement of repository heat into the fractured rocks accurate determination of thermodynamic and hydraulic properties is important. Heat capacity is one of the properties that are required to evaluate energy storage in the fractured rock. Rock-grain heat capacity, the subject of this study, is the heat capacity of the solid part of the rock. Yucca Mountain consists of alternating lithostratigraphic units of welded and non-welded ash-flow tuff, mainly rhyolitic in composition and displaying varying degrees of vitrification and alteration. A number of methods exist that can be used to evaluate heat capacity of the stratigraphic layers that consist of different compositions. In this study, the mineral summation method has been used to quantify the heat capacity of the stratigraphic layers based on Kopp's rule. The mineral summation method is an addition of the weighted heat capacity of each mineral found in a specific layer. For this study the weighting was done based on the mass percentage of each mineral in the layer. The method utilized a mineralogic map of the rocks at the Yucca Mountain repository site. The Calico Hills formation and adjacent bedded tuff layers display a bimodal mineral distribution of vitric and zeolitic zones with differing mineralogies. Based on this bimodal distribution in zeolite abundance, the boundary between the vitric and zeolitic zones was selected to be 15% zeolitic abundance. Thus, based on the zeolite abundance, subdivisions have been introduced to these layers into ''vitric'' and ''zeolitic'' zones. Heat capacity values have been calculated for these layers both as ''layer average'' and ''zone average''. The heat capacity determination method presented in this report did not account for spatial variability in the horizontal direction within each layer.

  14. Layering as Optimization Decomposition 3-1 Layering as OptimizationLayering as Optimization

    E-Print Network [OSTI]

    Fan, Xingzhe

    1 Layering as Optimization Decomposition 3-1 Layering as OptimizationLayering as Optimization DecompositionDecomposition Layering as Optimization Decomposition 3-2 CONTENTSCONTENTS Introduction (Marta;2 Layering as Optimization Decomposition 3-3 Layering as Optimization Decomposition Introduction By Marta

  15. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, T.W.

    1994-09-06T23:59:59.000Z

    A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

  16. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, Terry W. (Tracy, CA)

    1994-01-01T23:59:59.000Z

    A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

  17. Multiple layer insulation cover

    DOE Patents [OSTI]

    Farrell, James J. (Livingston Manor, NY); Donohoe, Anthony J. (Ovid, NY)

    1981-11-03T23:59:59.000Z

    A multiple layer insulation cover for preventing heat loss in, for example, a greenhouse, is disclosed. The cover is comprised of spaced layers of thin foil covered fabric separated from each other by air spaces. The spacing is accomplished by the inflation of spaced air bladders which are integrally formed in the cover and to which the layers of the cover are secured. The bladders are inflated after the cover has been deployed in its intended use to separate the layers of the foil material. The sizes of the material layers are selected to compensate for sagging across the width of the cover so that the desired spacing is uniformly maintained when the cover has been deployed. The bladders are deflated as the cover is stored thereby expediting the storage process and reducing the amount of storage space required.

  18. Nest predation, predator abundance, and avian diversity in transmission line corridors and adjacent habitats in east central Texas

    E-Print Network [OSTI]

    Hubbard, Tani Ann

    2000-01-01T23:59:59.000Z

    corridors may have differential effects on wildlife communities in adjacent vegetation types in a heterogeneous landscape. I evaluated the effects of ROW corridors on avian and nest predator communities in forests and pastures in east central Texas in 1998...

  19. Variety of c-axis collective excitations in layered multigap superconductors

    E-Print Network [OSTI]

    Yukihiro Ota; Masahiko Machida; Tomio Koyama

    2011-04-12T23:59:59.000Z

    We present a dynamical theory for the phase differences along a stacked direction of intrinsic Josephson junctions (IJJ's) in layered multigap superconductors, motivated by the discovery of highly-anisotropic iron-based superconductors with thick perovskite-type blocking layers. The dynamical equations describing AC and DC intrinsic Josephson effects peculiar to multigap IJJ's are derived, and collective Leggett mode excitations in addition to the Josephson plasma established in single-gap IJJ's are predicted. The dispersion relations of their collective modes are explicitly displayed, and the remarkable peculiarity of the Leggett mode is demonstrated.

  20. Statistics of avalanches in the self-organized criticality state of a Josephson junction

    SciTech Connect (OSTI)

    Matizen, E. V.; Martynets, V. G., E-mail: mart@niic.nsc.ru; Bezverkhii, P. P. [Russian Academy of Sciences, Nikolaev Institute of Inorganic Chemistry, Siberian Division (Russian Federation)

    2010-08-15T23:59:59.000Z

    Magnetic flux avalanches in Josephson junctions that include superconductor-insulator-superconductor (SIS) tunnel junctions and are magnetized at temperatures lower than approximately 5 K have been studied in detail. Avalanches are of stochastic character and appear when the magnetic field penetration depth {lambda} into a junction becomes equal to the length a of the Josephson junction with a decrease in the temperature. The statistical properties of such avalanches are presented. The size distribution of the avalanches is a power law with a negative noninteger exponent about unity, indicating the self-organized criticality state. The self-organized criticality state is not observed in Josephson junctions with a superconductor-normal metal-superconductor (SNS) junction.

  1. Self-consistent solution for proximity effect and Josephson current in ballistic graphene SNS Josephson junctions

    SciTech Connect (OSTI)

    Black-Schaffer, Annica M.

    2010-04-06T23:59:59.000Z

    We use a tight-binding Bogoliubov-de Gennes (BdG) formalism to self-consistently calculate the proximity effect, Josephson current, and local density of states in ballistic graphene SNS Josephson junctions. Both short and long junctions, with respect to the superconducting coherence length, are considered, as well as different doping levels of the graphene. We show that self-consistency does not notably change the current-phase relationship derived earlier for short junctions using the non-selfconsistent Dirac-BdG formalism but predict a significantly increased critical current with a stronger junction length dependence. In addition, we show that in junctions with no Fermi level mismatch between the N and S regions superconductivity persists even in the longest junctions we can investigate, indicating a diverging Ginzburg-Landau superconducting coherence length in the normal region.

  2. On the Harmonic approximation for large Josephson junction coupling charge qubits

    E-Print Network [OSTI]

    T. Shi; B. Chen; Z. Song; C. P. Sun

    2004-09-23T23:59:59.000Z

    We revisit the harmonic approximation (HA) for a large Josephson junction interacting with some charge qubits through the variational approach for the quantum dynamics of the junction-qubit coupling system. By making use of numerical calculation and analytical treatment, the conditions under which HA works well can be precisely presented to control the parameters implementing the two-qubit quantum logical gate through the couplings to the large junction with harmonic oscillator (HO) Hamiltonian.

  3. Characteristics of high-transmission-probability tunnel junctions for use as particle detectors

    SciTech Connect (OSTI)

    Stricker, D.A.; Alba, G.P.; Anderson, C.C.; Bing, D.D.; Bland, R.W.; Dickson, S.C.; Dignan, T.G.; Gagnon, P.; Johnson, R.T.; Seneclauze, C.M.

    1988-12-31T23:59:59.000Z

    Interest in the problem of the galactic dark matter has stimulated development of particle detectors sensitive to very low energies. Superconducting tunnel junctions may be useful in such detectors. We describe here superconducting tunnel junctions with thin barriers which may be suitable for this purpose. We present I-V characteristics and data on the temperature dependence of the subgap tunneling current. We also present some scanning-electron-microscope observations of the thin films of the tunnel junctions.

  4. Characteristics of high-transmission-probability tunnel junctions for use as particle detectors

    SciTech Connect (OSTI)

    Stricker, D.A.; Alba, G.P.; Anderson, C.C.; Bing, D.D.; Bland, R.W.; Dickson, S.C.; Dignan, T.G.; Gagnon, P.; Johnson, R.T.; Seneclauze, C.M.

    1988-01-01T23:59:59.000Z

    Interest in the problem of the galactic dark matter has stimulated development of particle detectors sensitive to very low energies. Superconducting tunnel junctions may be useful in such detectors. We describe here superconducting tunnel junctions with thin barriers which may be suitable for this purpose. We present I-V characteristics and data on the temperature dependence of the subgap tunneling current. We also present some scanning-electron-microscope observations of the thin films of the tunnel junctions.

  5. Characteristics of high-transmission-probability tunnel junctions for use as particle detectors

    SciTech Connect (OSTI)

    Stricker, D.A.; Alba, G.P.; Anderson, C.C.; Bing, D.D.; Bland, R.W.; Dickson, S.C.; Dignan, T.G.; Gagnon, P.; Johnson, R.T.; Seneclauze, C.M.

    1989-03-01T23:59:59.000Z

    Interest in the problem of the galactic dark matter has stimulated development of particle detectors sensitive to very low energies. Superconducting tunnel junctions may be useful in such detectors. The authors describe superconducting tunnel junctions with thin barriers which may be suitable for this purpose. They present I-V characteristics and data on the temperature dependence of the subgap tunneling current. They also present some scanning-electron-microscope observations of the thin films of the tunnel junctions.

  6. E-Print Network 3.0 - arsenic ultrashallow junctions Sample Search...

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

    High-Sensitivity Si-based VUV Photodiodes Summary: . Keywords- Vacuum Ultra-Violet; photodiode; ultrashallow junctions; series resistance; responsivity; time... to the device...

  7. Comment on "Analysis of quantum coherent semiconductor quantum dot p-i-n junction photovoltaic cells"

    E-Print Network [OSTI]

    Scully, Marlan O

    2010-01-01T23:59:59.000Z

    This is a comment on PRL paper by A.P. Kirk "Analysis of quantum coherent semiconductor quantum dot p-i-n junction photovoltaic cells"

  8. Estimating commuter rail demand to Kendall Square along the Grand Junction Corridor .

    E-Print Network [OSTI]

    Dohm, James

    2012-01-01T23:59:59.000Z

    ??Since acquiring the Grand Junction Railroad in June 2010 from CSX, the Massachusetts Bay Transit Authority (MBTA) has explored the possibility of using the line… (more)

  9. Mean-field dynamics of a Bose Josephson junction in an optical cavity

    E-Print Network [OSTI]

    J. M. Zhang; W. M. Liu; D. L. Zhou

    2008-04-22T23:59:59.000Z

    We study the mean-field dynamics of a Bose Josephson junction which is dispersively coupled to a single mode of a high-finesse optical cavity. An effective classical Hamiltonian for the Bose Josephson junction is derived and its dynamics is studied in the perspective of phase portrait. It is shown that the strong condensate-field coupling does alter the dynamics of the Bose Josephson junction drastically. The possibility of coherent manipulating and \\textsl{in situ} observation of the dynamics of the Bose Josephson junction is discussed.

  10. E-Print Network 3.0 - adherens junction homeostasis Sample Search...

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

    results for: adherens junction homeostasis Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: and Is Required for Adherens...

  11. E-Print Network 3.0 - adherens junction protein Sample Search...

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

    search results for: adherens junction protein Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: barrier and prevent the...

  12. E-Print Network 3.0 - adherens junction type Sample Search Results

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

    search results for: adherens junction type Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: of hypodermal and intestinal...

  13. E-Print Network 3.0 - annular josephson junctions Sample Search...

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

    << < 1 2 3 4 5 > >> 41 Collective Josephson vortex dynamics in a finite number of stacked intrinsic Josephson junctions Myung-Ho Bae,1, Summary: Collective Josephson vortex...

  14. E-Print Network 3.0 - atomic gold junction Sample Search Results

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

    ON APPLIED SUPERCONDUCTIVITY, VOL. 13, NO. 2, JUNE 2003 Novel In-Situ Fabricated Josephson Junctions Summary: the insulator and gold contacts are added. (d) Schematics...

  15. Electronic transport transition at graphene/YBa{sub 2}Cu{sub 3}O{sub 7??} junction

    SciTech Connect (OSTI)

    Sun, Q. J.; Wang, H. S. [School of Physics and Electronics, Central South University, Changsha 410083 (China) [School of Physics and Electronics, Central South University, Changsha 410083 (China); State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Wang, H. M., E-mail: hmwang@mail.sim.ac.cn; Gao, B.; Li, Q.; Xie, X. M. [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)] [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Deng, L. W.; Hu, Z. W. [School of Physics and Electronics, Central South University, Changsha 410083 (China)] [School of Physics and Electronics, Central South University, Changsha 410083 (China)

    2014-03-10T23:59:59.000Z

    We report the fabrication of graphene/YBa{sub 2}Cu{sub 3}O{sub 7??} contacts and their superconducting proximity effect. Both the temperature dependence of resistance and the current bias dependence of resistance for the contacts are investigated, respectively. The results are compared with that of pure YBCO Hall bar. It is found that the differential resistance transits from a non-zero value to zero at high bias across graphene/YBCO junction below the transition temperature of YBCO, the phenomena indicate the tunneling of Cooper pairs from YBCO to graphene. As the YBCO film deposited by pulsed laser deposition has a rough surface, the graphene layer can contact with the edge of CuO{sub 2} planes. It allows that Cooper pairs could leak into graphene along the CuO{sub 2} planes.

  16. GaSb based ternary and quaternary diffused junction devices for TPV applications

    SciTech Connect (OSTI)

    Sundaram, V.S.; Saban, S.B.; Morgan, M.D.; Horne, W.E.; Evans, B.D.; Ketterl, J.R. [EDTEK Inc. 7082 S. 220th Street Kent, Washington 98032 (United States); Morosini, M.B.; Patel, N.B. [Instituto de Fisica, UNICAMP, Campinas, Brasil (Brazil); Field, H. [NREL, Golden, Colorado (United States)

    1997-03-01T23:59:59.000Z

    In this work we report the characteristics of ternary, GaInSb (Eg=0.70eV) and quarternary, GaInAsSb (Eg=0.5eV) diffused junction photovoltaic devices. The unique feature of the quarternary device is the extended long-wavelength response to 2.1 microns enabling the efficient use of the blackbody-like thermal sources operating at 1373 K in thermophotovoltaic energy conversion systems. The ternary device was fabricated by diffusing zinc into a n-type (100) oriented GaInSb substrate. For the quarternary, a four micron thick Te doped GaInAsSb layer grown by LPE on a n-type GaSb(100) wafer was used as the starting substrate for zinc diffusion. The ternary device exhibits an open circuit voltage of 0.38 V, Fill Factor of 0.63 and a short circuit current of 0.8A/cm{sup 2}, while the corresponding values for the quarternary device are 0.25 V, 0.58 and 0.8A/cm{sup 2}, respectively. The peak internal quantum efficiency for the ternary is over 90{percent} and that of the quarternary is above 75{percent}. Process optimization should improve the performance charcateristics of the quarternary. {copyright} {ital 1997 American Institute of Physics.}

  17. Influence of hydrogen patterning gas on electric and magnetic properties of perpendicular magnetic tunnel junctions

    SciTech Connect (OSTI)

    Jeong, J. H., E-mail: juno@fris.tohoku.ac.jp [Graduate School of Engineering, Tohoku University, Sendai (Japan); Semiconductor R and D Center, Samsung Electronics Co., Ltd., Hwasung (Korea, Republic of); Endoh, T. [Graduate School of Engineering, Tohoku University, Sendai (Japan); Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai (Japan); Kim, Y.; Kim, W. K.; Park, S. O. [Semiconductor R and D Center, Samsung Electronics Co., Ltd., Hwasung (Korea, Republic of)

    2014-05-07T23:59:59.000Z

    To identify the degradation mechanism in magnetic tunnel junctions (MTJs) using hydrogen, the properties of the MTJs were measured by applying an additional hydrogen etch process and a hydrogen plasma process to the patterned MTJs. In these studies, an additional 50?s hydrogen etch process caused the magnetoresistance (MR) to decrease from 103% to 14.7% and the resistance (R) to increase from 6.5?k? to 39?k?. Moreover, an additional 500?s hydrogen plasma process decreased the MR from 103% to 74% and increased R from 6.5?k? to 13.9?k?. These results show that MTJs can be damaged by the hydrogen plasma process as well as by the hydrogen etch process, as the atomic bonds in MgO may break and react with the exposed hydrogen gas. Compounds such as MgO hydrate very easily. We also calculated the damaged layer width (DLW) of the patterned MTJs after the hydrogen etching and plasma processes, to evaluate the downscaling limitations of spin-transfer-torque magnetic random-access memory (STT-MRAM) devices. With these calculations, the maximum DLWs at each side of the MTJ, generated by the etching and plasma processes, were 23.8?nm and 12.8?nm, respectively. This result validates that the hydrogen-based MTJ patterning processes cannot be used exclusively in STT-MRAMs beyond 20?nm.

  18. Front contact solar cell with formed electrically conducting layers on the front side and backside

    DOE Patents [OSTI]

    Cousins, Peter John

    2012-06-26T23:59:59.000Z

    A bipolar solar cell includes a backside junction formed by a silicon substrate and a first doped layer of a first dopant type on the backside of the solar cell. A second doped layer of a second dopant type makes an electrical connection to the substrate from the front side of the solar cell. A first metal contact of a first electrical polarity electrically connects to the first doped layer on the backside of the solar cell, and a second metal contact of a second electrical polarity electrically connects to the second doped layer on the front side of the solar cell. An external electrical circuit may be electrically connected to the first and second metal contacts to be powered by the solar cell.

  19. Ion Mobility Separation of Isomeric Phosphopeptides from a Protein with Variant Modification of Adjacent Residues

    SciTech Connect (OSTI)

    Shvartsburg, Alexandre A.; Singer, David; Smith, Richard D.; Hoffmann, Ralf

    2011-06-13T23:59:59.000Z

    Ion mobility spectrometry (IMS), and particularly differential IMS or field asymmetric waveform IMS (FAIMS), was recently shown capable of separating post-translationally modified peptides with variant PTM localization. However, that work was limited to a model peptide with serine phosphorylation on fairly distant alternative sites. Here, we demonstrate that FAIMS (coupled to ESI/MS) can broadly baseline-resolve variant phosphopeptides from a biologically modified human protein, including those involving phosphorylation of different residues and adjacent sites that existing MS/MS methods are most challenged to distinguish. Singly and doubly phosphorylated variants can be resolved equally well and identified without dissociation, based on accurate separation properties. The results are unchanged over a range of infusion solvent pH, hence present approach should work in conjunction with chromatographic separations using a mobile phase gradient.

  20. The planar X-junction flow: stability analysis and control

    E-Print Network [OSTI]

    Lashgari, Iman; Tammisola, Outi; Citro, Vincenzo; Juniper, Matthew P.; Brandt, Luca

    2014-07-29T23:59:59.000Z

    and ? is the kinematic viscosity. The velocity ratio is defined as Vr = U2 U1 , (2.2) where U2 is the maximum inflow velocity of the side channels. In this paper, we study the stability of the X-junction flow in the Reynolds number regime 60 waves, and the lift-up effect. To determine the instability mechanism in our flow, we note that the present instability is stationary, the mode shape streamwise elon- gated, and the streamwise velocity component order of magnitude larger than...

  1. Replica Theory and Large D Josephson Junction Hypercubic Models

    E-Print Network [OSTI]

    Enzo Marinari; Giorgio Parisi; Felix Ritort

    1995-02-16T23:59:59.000Z

    We study the statistical mechanics of a $D$-dimensional array of Josephson junctions in presence of a magnetic field on a lattice of side $2$. In the high temperature region the thermodynamical properties can be computed in the limit $D \\to \\infty$. A conjectural form of the thermodynamic properties in the low temperature phase is obtained by assuming that they are the same of an appropriate spin glass system, based on quenched disordered couplings. Numerical simulations show that this conjecture is very accurate in one regime of the magnetic field, while it is probably slightly inaccurate in a second regime.

  2. Dynamics of Josephson junction systems in the computational subspace

    E-Print Network [OSTI]

    Wang Xiang-Bin; Matsumoto Keiji; Fan Heng; Y. Nakamura

    2001-12-05T23:59:59.000Z

    The quantum dynamics of the Josephson junction system in the computational subspace is investigated. A scheme for the controlled not operation is given for two capasitively coupled SQUIDs. In this system, there is no systematic error for the two qubit operation. For the inductively coupled SQUIDs, the effective Hamiltonian causes systematic errors in the computational subspace for the two qubit operation. Using the purterbation theory, we construct a more precise effective Hamiltonian. This new effective Hamiltonian reduces the systematic error to the level much lower than the threshold of the fault resilent quantum computation.

  3. Nanopillar Spin Filter Tunnel Junctions with Manganite Barriers

    E-Print Network [OSTI]

    Prasad, Bhagwati; Egilmez, Mehmet; Schoofs, Frank; Fix, Thomas; Vickers, Mary E; Zhang, Wenrui; Jian, Jie; Wang, Haiyan; Blamire, Mark G

    2014-04-17T23:59:59.000Z

    promising FI tunnel barrier material for SFTJ. In this work, we investigate the spin filtering properties of Sm0.75Sr0.25MnO3 (SSMO) manganite ultrathin films in LNO/SSMO/LNO tunnel junctions. SSMO films were grown by pulsed laser deposition (PLD) onto Sr... -plane rotation vis-à-vis the substrate, i.e. the alignment of [110] of orthorhombic SSMO with the [100] of the underlying cubic SrTiO3 (STO) substrate. Film thickness was calculated from both X-ray reflectivity (not shown) and diffraction fringes around the (004...

  4. Electron transport in normal-metal/superconductor junctions

    E-Print Network [OSTI]

    Yan, XZ; Zhao, HW; Hu, Chia-Ren.

    2000-01-01T23:59:59.000Z

    . 1. Conductance G as a function of the voltage V for an NS (d-wave! junction with $100% interface at T50 and t0 /t50.5. The present calculation ~solid line! is compared with the BTK result ~dashed line!. PRB 61ZHAO, AND CHIA-REN HU FIG. 2.... The same as Fig. 1 but at t0 /t51. dominant contribution to the conductance in the BTK theory. Under the present assumption, however, the transport is due to the decay of quasiparticles in both sides. Such a decaying process is more complex than the BTK...

  5. Anomalous Finite-Size Effect in Superconducting Josephson Junction Arrays

    SciTech Connect (OSTI)

    Chen, Qing-Hu; Tang, Lei-Han; Tong, Peiqing

    2001-08-06T23:59:59.000Z

    We show that a previously reported discrepancy between simulations of superconducting Josephson junction arrays and the theoretical analysis of Ambegaokar, Halperin, Nelson, and Siggia (AHNS) [Phys. Rev. Lett. 40, 783 (1978)] is rooted in a peculiar finite-size effect under periodic boundary conditions. Our simulation results for the largest array support the power-law I-V curves predicted by AHNS. Analysis of the vortex dynamics reveals two intrinsic length scales set by the applied current, which define three size regimes with distinctive I-V characteristics.

  6. Transitions in two sinusoidally coupled Josephson junction rotators

    SciTech Connect (OSTI)

    Qian Min [School of Mathematical Sciences, Peking University, Beijing 100871 (China); Wang Jiazeng [Department of Mathematics, Shanghai University, Shanghai 200444 (China)], E-mail: wangjiazen@yahoo.com.cn

    2008-08-15T23:59:59.000Z

    We investigate the dynamics of two sinusoidally coupled Josephson junction rotators to provide a clear knowledge of the behaviors in different regions of the parameter space. The dynamical states are identified, and the transitions among these states are studied. The properties of the current-voltage curves are investigated. Further more, we observed the chaotic states in some regions of parameter space. We conjecture it may caused by the competition of two periodic potentials: one is the external field, another is the interacting of two particles.

  7. Coherent Oscillations in an Exciton-Polariton Josephson Junction

    SciTech Connect (OSTI)

    Lagoudakis, K. G.; Pietka, B.; Deveaud-Pledran, B. [ICMP, Ecole Polytechnique Federale de Lausanne (EPFL), 1015 Lausanne (Switzerland); Wouters, M. [ITP, Ecole Polytechnique Federale de Lausanne (EPFL), 1015 Lausanne (Switzerland); Andre, R. [Institut Neel, CNRS, Grenoble (France)

    2010-09-17T23:59:59.000Z

    We report on the observation of spontaneous coherent oscillations in a microcavity polariton bosonic Josephson junction. Condensation of exciton polaritons here takes place under incoherent excitation in a double potential well naturally formed in the disorder. Coherent oscillations set on at an excitation power well above the condensation threshold. The time resolved population and phase dynamics reveal the analogy with the ac Josephson effect. A theoretical two-mode model describes the observed effects, explaining how the different realizations of the pulsed experiment can be in phase.

  8. Tunneling qubit operation on a protected Josephson junction array

    SciTech Connect (OSTI)

    Yin Zhi; Li Shengwen; Chen Yixin [Zhejiang Insitute of Modern Physics, Zhejiang University, Hangzhou 310027 (China)

    2010-01-15T23:59:59.000Z

    We propose a complete quantum computation process on a topologically protected Josephson junction array system, originally proposed by Ioffe and Feigel'man [Phys. Rev. B 66, 224503 (2002)]. Logical qubits for computation are encoded in the punctured array. The number of qubits is determined by the number of holes. The topological degeneracy is lightly shifted by tuning the flux along specific paths. We show how to perform both single-qubit and basic quantum-gate operations in this system, especially the controlled-NOT (CNOT) gate.

  9. Resonantly phase-matched Josephson junction traveling wave parametric amplifier

    E-Print Network [OSTI]

    Kevin O'Brien; Chris Macklin; Irfan Siddiqi; Xiang Zhang

    2014-06-09T23:59:59.000Z

    We develop a technique to overcome phase-mismatch in Josephson-junction traveling wave parametric amplifiers in order to achieve high gain over a broad bandwidth. Using "resonant phase matching," we design a compact superconducting device consisting of a transmission line with subwavelength resonant inclusions that simultaneously achieves a gain of 20 dB, an instantaneous bandwidth of 3 GHz, and a saturation power of -98 dBm. Such an amplifier is well-suited to cryogenic broadband microwave measurements such as the multiplexed readout of quantum coherent circuits based on superconducting, semiconducting, or nano-mechanical elements as well as traditional astronomical detectors.

  10. DOE - Office of Legacy Management -- Grand Junction Sites

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou are here Home »HillNYEraGeneralGrand Junction Sites

  11. SEISMIC RESPONSE PREDICTION OF NUPEC'S FIELD MODEL TESTS OF NPP STRUCTURES WITH ADJACENT BUILDING EFFECT.

    SciTech Connect (OSTI)

    XU,J.COSTANTINO,C.HOFMAYER,C.ALI,S.

    2004-03-04T23:59:59.000Z

    As part of a verification test program for seismic analysis computer codes for Nuclear Power Plant (NPP) structures, the Nuclear Power Engineering Corporation (NUPEC) of Japan has conducted a series of field model tests to address the dynamic cross interaction (DCI) effect on the seismic response of NPP structures built in close proximity to each other. The program provided field data to study the methodologies commonly associated with seismic analyses considering the DCI effect. As part of a collaborative program between the United States and Japan on seismic issues related to NPP applications, the U.S. Nuclear Regulatory Commission sponsored a program at Brookhaven National Laboratory (BNL) to perform independent seismic analyses which applied common analysis procedures to predict the building response to recorded earthquake events for the test models with DCI effect. In this study, two large-scale DCI test model configurations were analyzed: (1) twin reactor buildings in close proximity and (2) adjacent reactor and turbine buildings. This paper describes the NUPEC DCI test models, the BNL analysis using the SASSI 2000 program, and comparisons between the BNL analysis results and recorded field responses. To account for large variability in the soil properties, the conventional approach of computing seismic responses with the mean, mean plus and minus one-standard deviation soil profiles is adopted in the BNL analysis and the three sets of analysis results were used in the comparisons with the test data. A discussion is also provided in the paper to address (1) the capability of the analysis methods to capture the DCI effect, and (2) the conservatism of the practice for considering soil variability in seismic response analysis for adjacent NPP structures.

  12. Structured luminescence conversion layer

    DOE Patents [OSTI]

    Berben, Dirk; Antoniadis, Homer; Jermann, Frank; Krummacher, Benjamin Claus; Von Malm, Norwin; Zachau, Martin

    2012-12-11T23:59:59.000Z

    An apparatus device such as a light source is disclosed which has an OLED device and a structured luminescence conversion layer deposited on the substrate or transparent electrode of said OLED device and on the exterior of said OLED device. The structured luminescence conversion layer contains regions such as color-changing and non-color-changing regions with particular shapes arranged in a particular pattern.

  13. Layered Spinach Salad Ingredients

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    cucumbers 2 tomatoes 1/2 cup low-fat mayonnaise 1/2 cup parmesan cheese, grated 1/4 cup milk 1 1/2 teaspoons size pieces, layer on bottom of a large bowl. 2. Rinse mushrooms off under cool water and use a soft half. Layer on top of vegetables. 6. To make salad dressing, add mayonnaise, cheese, milk, dill weed

  14. Fabrication of contacts for silicon solar cells including printing burn through layers

    DOE Patents [OSTI]

    Ginley, David S; Kaydanova, Tatiana; Miedaner, Alexander; Curtis, Calvin J; Van Hest, Marinus Franciscus Antonius Maria

    2014-06-24T23:59:59.000Z

    A method for fabricating a contact (240) for a solar cell (200). The method includes providing a solar cell substrate (210) with a surface that is covered or includes an antireflective coating (220). For example, the substrate (210) may be positioned adjacent or proximate to an outlet of an inkjet printer (712) or other deposition device. The method continues with forming a burn through layer (230) on the coating (220) by depositing a metal oxide precursor (e.g., using an inkjet or other non-contact printing method to print or apply a volume of liquid or solution containing the precursor). The method includes forming a contact layer (240) comprising silver over or on the burn through layer (230), and then annealing is performed to electrically connect the contact layer (240) to the surface of the solar cell substrate (210) through a portion of the burn through layer (230) and the coating (220).

  15. Inverted GaInP/(In)GaAs/InGaAs Triple-Junction Solar Cells with Low-Stress Metamorphic Bottom Junctions: Preprint

    SciTech Connect (OSTI)

    Geisz, J. F.; Kurtz, S. R.; Wanlass, M. W.; Ward, J. S.; Duda, A.; Friedman, D. J.; Olson, J. M.; McMahon, W. E.; Moriarty, T. E.; Kiehl, J. T.; Romero, M. J.; Norman, A. G.; Jones, K. M.

    2008-05-01T23:59:59.000Z

    We demonstrate high efficiency performance in two ultra-thin, Ge-free III-V semiconductor triple-junction solar cell device designs grown in an inverted configuration. Low-stress metamorphic junctions were engineered to achieve excellent photovoltaic performance with less than 3 x 106 cm-2 threading dislocations. The first design with band gaps of 1.83/1.40/1.00 eV, containing a single metamorphic junction, achieved 33.8% and 39.2% efficiencies under the standard one-sun global spectrum and concentrated direct spectrum at 131 suns, respectively. The second design with band gaps of 1.83/1.34/0.89 eV, containing two metamorphic junctions achieved 33.2% and 40.1% efficiencies under the standard one-sun global spectrum and concentrated direct spectrum at 143 suns, respectively.

  16. Layered electrode for electrochemical cells

    DOE Patents [OSTI]

    Swathirajan, Swathy (West Bloomfield, MI); Mikhail, Youssef M. (Sterling Heights, MI)

    2001-01-01T23:59:59.000Z

    There is provided an electrode structure comprising a current collector sheet and first and second layers of electrode material. Together, the layers improve catalyst utilization and water management.

  17. Josephson Junctions and AdS/CFT Networks

    E-Print Network [OSTI]

    Elias Kiritsis; Vasilis Niarchos

    2011-10-06T23:59:59.000Z

    We propose a new holographic model of Josephson junctions (and networks thereof) based on designer multi-gravity, namely multi-(super)gravity theories on products of distinct asymptotically AdS spacetimes coupled by mixed boundary conditions. We present a simple model of a Josephson junction (JJ) that exhibits the well-known current-phase sine relation of JJs. In one-dimensional chains of holographic superconductors we find that the Cooper-pair condensates are described by a discretized Schrodinger-type equation. Such non-integrable equations, which have been studied extensively in the past in condensed matter and optics applications, are known to exhibit complex behavior that includes periodic and quasiperiodic solutions, chaotic dynamics, soliton and kink solutions. In our setup these solutions translate to holographic configurations of strongly-coupled superconductors in networks with weak site-to-site interactions that exhibit interesting patterns of modulated superconductivity. In a continuum limit our equations reduce to generalizations of the Gross-Pitaevskii equation. We comment on the many possible extensions and applications of this new approach.

  18. Diffusion current in a system of coupled Josephson junctions

    SciTech Connect (OSTI)

    Shukrinov, Yu. M., E-mail: shukrinv@theor.jinr.ru; Rahmonov, I. R. [Joint Institute for Nuclear Research (Russian Federation)

    2012-08-15T23:59:59.000Z

    The role of a diffusion current in the phase dynamics of a system of coupled Josephson junctions (JJs) has been analyzed. It is shown that, by studying the temporal dependences of the superconducting, quasi-particle, diffusion, and displacement currents and the dependences of average values of these currents on the total current, it is possible to explain the main features of the current-voltage characteristic (CVC) of the system. The effect of a diffusion current on the character of CVC branching in the vicinity of a critical current and in the region of hysteresis, as well as on the part of CVC branch corresponding to a parametric resonance in the system is demonstrated. A clear interpretation of the differences in the character of CVC branching in a model of capacitively coupled JJs (CCJJ model) and a model of capacitive coupling with diffusion current (CCJJ+DC model) is proposed. It is shown that a decrease in the diffusion current in a JJ leads to the switching of this junction to an oscillating state. The results of model calculations are qualitatively consistent with the experimental data.

  19. On the Chaotic Flux Dynamics in a Long Josephson Junction

    E-Print Network [OSTI]

    Z. C. Feng; Y. Charles Li

    2009-07-16T23:59:59.000Z

    Flux dynamics in an annular long Josephson junction is studied. Three main topics are covered. The first is chaotic flux dynamics and its prediction via Melnikov integrals. It turns out that DC current bias cannot induce chaotic flux dynamics, while AC current bias can. The existence of a common root to the Melnikov integrals is a necessary condition for the existence of chaotic flux dynamics. The second topic is on the components of the global attractor and the bifurcation in the perturbation parameter measuring the strength of loss, bias and irregularity of the junction. The global attractor can contain co-existing local attractors e.g. a local chaotic attractor and a local regular attractor. In the infinite dimensional phase space setting, the bifurcation is very complicated. Chaotic attractors can appear and disappear in a random fashion. Three types of attractors (chaos, breather, spatially uniform and temporally periodic attractor) are identified. The third topic is ratchet effect. Ratchet effect can be achieved by a current bias field which corresponds to an asymmetric potential, in which case the flux dynamics is ever lasting chaotic. When the current bias field corresponds to a symmetric potential, the flux dynamics is often transiently chaotic, in which case the ratchet effect disappears after sufficiently long time.

  20. A new junction termination technique: the Deep Trench Termination (DT2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A new junction termination technique: the Deep Trench Termination (DT2 ) L. Théolier1,2 , H. Mahfoz. In this work, a new concept of low cost, low surface and high efficiency junction termination for power devices is presented and experimentally validated. This termination is based on a large and deep trench filled by BCB

  1. NREL scientists develop near-field optical microscopy techniques for imaging solar cell junctions and identify

    E-Print Network [OSTI]

    and Characterization team examined local junction breakdown in silicon and thin-film solar cells by electroluminescenceNREL scientists develop near-field optical microscopy techniques for imaging solar cell junctions is an increasingly important issue for silicon solar cells. The issue has taken center stage now that the solar

  2. TM-mode coupling to a Josephson junction S. J. Lewandowski

    E-Print Network [OSTI]

    Boyer, Edmond

    215 TM-mode coupling to a Josephson junction S. J. Lewandowski Instytut Fizyki PAN, 02-668 Warszawa-mode near cut-off are demonstrated to improve Josephson junction coupling to the waveguide. Revue Phys. Appl Sciences and available at http://dx.doi.org/10.1051/rphysap:01985002003021500 #12;216 Fig. 1. - Josephson

  3. Nonlinear Phase Dynamics in a Driven Bosonic Josephson Junction Erez Boukobza,1

    E-Print Network [OSTI]

    Vardi, Amichay

    Nonlinear Phase Dynamics in a Driven Bosonic Josephson Junction Erez Boukobza,1 Michael G. Moore,2. The experimental realization of dilute-gas Bose-Einstein condensate (BEC) Josephson junctions [2­ 5] has led], in a double-BEC system in Ref. [13], and in a one-dimensional spinor BEC in Ref. [14]. The bosonic Josephson

  4. A Hamilton-Jacobi approach to junction problems and application to traffic flows

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A Hamilton-Jacobi approach to junction problems and application to traffic flows C. Imbert , R of a model case of first order Hamilton-Jacobi equations posed on a "junction", that is to say the union of such problems. Keywords: Hamilton-Jacobi equations, discontinuous Hamiltonians, viscosity solutions, optimal

  5. Phonon Bottleneck in Graphene-Based Josephson Junctions at Millikelvin Temperatures I. V. Borzenets,1

    E-Print Network [OSTI]

    Finkelstein, Gleb

    Phonon Bottleneck in Graphene-Based Josephson Junctions at Millikelvin Temperatures I. V. Borzenets and superconducting branches in superconductor-graphene-superconductor Josephson junctions. We attribute thermalization by phonons at low temperatures (T & 1 K). The relationship between the applied power

  6. Photovoltaic nanopillar radial junction diode architecture enhanced by integrating semiconductor quantum dot nanocrystals as light harvesters

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Photovoltaic nanopillar radial junction diode architecture enhanced by integrating semiconductor hybridized, radial p-n junction based, nanopillar solar cells with photovoltaic performance enhanced. By furnishing Si based nanopillar photovoltaic diodes with CdSe quantum dots, we experimentally showed up

  7. Josephson junction of non-Abelian superconductors and non-Abelian Josephson vortices

    E-Print Network [OSTI]

    Muneto Nitta

    2015-02-09T23:59:59.000Z

    A Josephson junction is made of two superconductors sandwiching an insulator, and a Josephson vortex is a magnetic vortex absorbed into the Josephson junction, whose dynamics can be described by the sine-Gordon equation. In a field theory framework, a flexible Josephson junction was proposed, in which the Josephson junction is represented by a domain wall separating two condensations and a Josephson vortex is a sine-Gordon soliton in the domain wall effective theory. In this paper, we propose a Josephson junction of non-Abelian color superconductors, that is described by a non-Abelian domain wall, and show that a non-Abelian vortex (color magnetic flux tube) absorbed into it is a non-Abelian Josephson vortex represented as a non-Abelian sine-Gordon soliton in the domain wall effective theory.

  8. Josephson junction of non-Abelian superconductors and non-Abelian Josephson vortices

    E-Print Network [OSTI]

    Nitta, Muneto

    2015-01-01T23:59:59.000Z

    A Josephson junction is made of two superconductors sandwiching an insulator, and a Josephson vortex is a magnetic vortex absorbed into the Josephson junction, whose dynamics can be described by the sine-Gordon equation. In a field theory framework, a flexible Josephson junction was proposed, in which the Josephson junction is represented by a domain wall separating two condensations and a Josephson vortex is a sine-Gordon soliton in the domain wall effective theory. In this paper, we propose a Josephson junction of non-Abelian color superconductors, that is described by a non-Abelian domain wall, and show that a non-Abelian vortex (color magnetic flux tube) absorbed into it is a non-Abelian Josephson vortex represented as a non-Abelian sine-Gordon soliton in the domain wall effective theory.

  9. Imaging the p-n junction in a gallium nitride nanowire with a scanning microwave microscope

    SciTech Connect (OSTI)

    Imtiaz, Atif [Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Department of Electrical, Computer, and Energy Engineering, University of Colorado, Boulder, Colorado 80309 (United States); Wallis, Thomas M.; Brubaker, Matt D.; Blanchard, Paul T.; Bertness, Kris A.; Sanford, Norman A.; Kabos, Pavel, E-mail: kabos@boulder.nist.gov [Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Weber, Joel C. [Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309 (United States); Coakley, Kevin J. [Information Technology Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States)

    2014-06-30T23:59:59.000Z

    We used a broadband, atomic-force-microscope-based, scanning microwave microscope (SMM) to probe the axial dependence of the charge depletion in a p-n junction within a gallium nitride nanowire (NW). SMM enables the visualization of the p-n junction location without the need to make patterned electrical contacts to the NW. Spatially resolved measurements of S{sub 11}{sup ?}, which is the derivative of the RF reflection coefficient S{sub 11} with respect to voltage, varied strongly when probing axially along the NW and across the p-n junction. The axial variation in S{sub 11}{sup ?}? effectively mapped the asymmetric depletion arising from the doping concentrations on either side of the junction. Furthermore, variation of the probe tip voltage altered the apparent extent of features associated with the p-n junction in S{sub 11}{sup ?} images.

  10. Overdamped Nb/Al-AlO{sub x}/Nb Josephson junctions

    SciTech Connect (OSTI)

    Lacquaniti, V.; Cagliero, C.; Maggi, S.; Steni, R. [Thin Films Department, IEN 'G. Ferraris', Strada delle Cacce 91, I-10135, Torino (Italy)

    2005-01-24T23:59:59.000Z

    We report the fabrication and characterization of overdamped Nb/Al-AlO{sub x}/Nb superconductor-insulator-superconductor Josephson junction whose fabrication process derives from that of the well-known hysteretic junctions. These junctions are an intermediate state between the superconductor-normal metal-superconductor and the superconductor-insulator-superconductor Josephson junctions. Stable and reproducible nonhysteretic current-voltage characteristics are obtained with a proper choice of the fabrication parameters. We have measured critical current densities J{sub C} from 10{sup 3} up to 2x10{sup 4} A/cm{sup 2}, with characteristic voltages from 80 to nearly 450 {mu}V. The junctions are stable against time and repeated thermal cycling.

  11. Model for a Josephson junction array coupled to a resonant cavity

    SciTech Connect (OSTI)

    Harbaugh, J. Kent [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States)] [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States); Stroud, D. [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States)] [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States)

    2000-06-01T23:59:59.000Z

    We describe a simple Hamiltonian for an underdamped Josephson array coupled to a single photon mode in a resonant cavity. Using a Hartree-like mean-field theory, we show that, for any given strength of coupling between the photon field and the Josephson junctions, there is a transition from incoherence to coherence as a function of N, the number of Josephson junctions in the array. Above that value of N, the energy in the photon field is proportional to N{sup 2}, suggestive of coherent emission. These features remain even when the junction parameters have some random variation from junction to junction, as expected in a real array. Both of these features agree with recent experiments by Barbara and co-workers. (c) 2000 The American Physical Society.

  12. Wafer Bonding and Layer Transfer Processes for High Efficiency Solar Cells

    SciTech Connect (OSTI)

    Zahler, J. M.; Fontcuberta i Morral, A.; Ahn, C. G.; Atwater, H. A.; Wanlass, M. W.; Chu, C.; Iles, P. A.

    2003-05-01T23:59:59.000Z

    A wafer-bonded four-junction cell design consisting of InGaAs, InGaAsP, GaAs, and Ga0.5In0.5P subcells that could reach one-sun AM0 efficiencies of 35.4% is described. The design relies on wafer-bonding and layer transfer for integration of non-lattice-matched subcells. Wafer bonding and layer transfer processes have shown promise in the fabrication of InP/Si epitaxial templates for growth of the bottom InGaAs and InGaAsP subcells on a Si support substrate. Subsequent wafer bonding and layer transfer of a thin Ge layer onto the lower subcell stack can serve as an epitaxial template for GaAs and Ga0.5In0.5P subcells. Additionally, wafer bonded Ge/Si substrates offer the possibility to improve the mechanical performance of existing triple-junction solar cell designs, while simultaneously reducing their cost. Present results indicate that optically active III/V compound semiconductors can be grown on both Ge/Si and InP/Si heterostructures. Current-voltage electrical characterization of the interfaces of these structures indicates that both InP/Si and Ge/Si interfaces have specific resistances lower than 0.1 W?cm2 for heavily doped wafer bonded interfaces, enabling back surface power extraction from the finished cell structure.

  13. Magneto-electric coupling in a two-dimensional ballistic Josephson junction with in-plane magnetic texture

    E-Print Network [OSTI]

    Boyer, Edmond

    Magneto-electric coupling in a two-dimensional ballistic Josephson junction with in-plane magnetic, Germany (Dated: August 20, 2014) We study a Josephson junction made with a spin-textured bridge, when both-dimensional ballistic Josephson junction close to the critical temperature of the heterostructure, when an anomalous

  14. PHYSICAL REVIEW E 88, 022908 (2013) Synchronization of a Josephson junction array in terms of global variables

    E-Print Network [OSTI]

    Pikovsky, Arkady

    PHYSICAL REVIEW E 88, 022908 (2013) Synchronization of a Josephson junction array in terms of Josephson junctions with a common LCR load. Application of the Watanabe-Strogatz approach [Physica D 74, 197 of oscillating physical systems that being coupled synchronize are Josephson junctions [2]. In theoretical

  15. Model for a Josephson junction array coupled to a resonant cavity J. Kent Harbaugh and D. Stroud

    E-Print Network [OSTI]

    Stroud, David

    Model for a Josephson junction array coupled to a resonant cavity J. Kent Harbaugh and D. Stroud junctions, there is a transition from incoherence to coherence as a function of N, the number of Josephson-capacitance and underdamped Josephson junctions, quantum phase fluctua- tions inhibit phase locking.8­13 Thus, until recently

  16. Electrically Tunable Macroscopic Quantum Tunneling in a Graphene-Based Josephson Junction Gil-Ho Lee,1

    E-Print Network [OSTI]

    Lee, Hu-Jong

    Electrically Tunable Macroscopic Quantum Tunneling in a Graphene-Based Josephson Junction Gil.1103/PhysRevLett.107.146605 PACS numbers: 72.80.Vp, 73.40.Ã?c, 74.45.+c, 85.25.Cp A Josephson junction [1 the fabri- cation of nanostructured proximity-coupled Josephson junctions based on conducting spacers

  17. Incommensurate dynamics of resonant breathers in Josephson junction ladders M. V. Fistul, A. E. Miroshnichenko, and S. Flach

    E-Print Network [OSTI]

    Flach, Sergej

    Incommensurate dynamics of resonant breathers in Josephson junction ladders M. V. Fistul, A. E and experimental studies of resonant localized resistive states in a Josephson junction ladder. These complex guides, in antiferromagnetic solids and in systems of interacting Josephson junctions.8­13 Especially

  18. Eigenstates of a small Josephson junction coupled to a resonant cavity W. A. Al-Saidi* and D. Stroud

    E-Print Network [OSTI]

    Stroud, David

    Eigenstates of a small Josephson junction coupled to a resonant cavity W. A. Al-Saidi* and D; published 4 December 2001 We carry out a quantum-mechanical analysis of a small Josephson junction coupled the lowest two levels of the Josephson junction are retained in the Hamiltonian matrix. We noticed

  19. Charging Effects in the Inductively Shunted Josephson Junction Jens Koch, V. Manucharyan, M. H. Devoret, and L. I. Glazman

    E-Print Network [OSTI]

    Devoret, Michel H.

    Charging Effects in the Inductively Shunted Josephson Junction Jens Koch, V. Manucharyan, M. H to shunt a Josephson junction determines if the charge transferred through the circuit is quantized by charge noise. DOI: 10.1103/PhysRevLett.103.217004 PACS numbers: 85.25.Cp, 74.50.+r The Josephson junction

  20. Observation of High Coherence in Josephson Junction Qubits Measured in a Three-Dimensional Circuit QED Architecture

    E-Print Network [OSTI]

    Observation of High Coherence in Josephson Junction Qubits Measured in a Three-Dimensional Circuit December 2011) Superconducting quantum circuits based on Josephson junctions have made rapid progress the intrinsic coherence of Josephson junctions, and whether superconducting qubits can be adequately isolated

  1. Collective dynamics of Josephson fluxons in Bi2Sr2CaCu2O8d intrinsic junctions

    E-Print Network [OSTI]

    Lee, Hu-Jong

    in naturally stacked intrinsic Josephson junctions in Bi2Sr2- CaCu2O8þd single crystals were studied Keywords: Fluxon dynamics; Intrinsic Josephson junctions; Plasma excitation modes; Superradiant state 1 to high-frequency devices such as THz local oscilla- tors and mixers. Stacked long Josephson junctions

  2. Scanning tunneling microscope tip as a positionable contact: Probing a Josephson-junction array at subkelvin temperatures

    E-Print Network [OSTI]

    Scanning tunneling microscope tip as a positionable contact: Probing a Josephson-junction arrayK. The STM enables us to probe the structure, a Josephson-junction array, at various positions. Examples of such systems are two- dimensional electron gases and Josephson junction arrays.1

  3. Three-dimensional Josephson-junction arrays: Static magnetic response R. De Luca and T. Di Matteo

    E-Print Network [OSTI]

    Di Matteo, Tiziana

    Three-dimensional Josephson-junction arrays: Static magnetic response R. De Luca and T. Di Matteo Tampere, Finland Received 17 July 1997 In this work we present a simple three-dimensional Josephson-junction directions perpendicular to one cube side. S0163-1829 98 05502-7 I. INTRODUCTION The interest in Josephson-junction

  4. Microscopic model of critical current noise in Josephson-junction qubits: Subgap resonances and Andreev bound states

    E-Print Network [OSTI]

    von Delft, Jan

    Microscopic model of critical current noise in Josephson-junction qubits: Subgap resonances in Josephson junctions based on individual trapping centers in the tunnel-barrier hybridized with electrons microresonators observed in Josephson-junction qubits R. W. Simmonds et al., Phys. Rev. Lett. 93, 077003 2004

  5. Nonlinear microwave impedance of short and long Josephson junctions Z. Zhai, Patanjali V. Parimi, and S. Sridhar

    E-Print Network [OSTI]

    Sridhar, Srinivas

    Nonlinear microwave impedance of short and long Josephson junctions Z. Zhai, Patanjali V. Parimi ) of the microwave ac impedance R iX of both short and long Josephson junctions is calculated under a variety and fabricated Josephson junctions in the high temperature superconductors. When a dc field (bdc) or current (idc

  6. Rabi Oscillations in a Large Josephson-Junction Qubit John M. Martinis, S. Nam, and J. Aumentado*

    E-Print Network [OSTI]

    Martinis, John M.

    Rabi Oscillations in a Large Josephson-Junction Qubit John M. Martinis, S. Nam, and J. Aumentado based on a large-area current-biased Josephson junction whose two lowest energy quantum levels are used. In this Letter, we present a new qubit designed around a 10 m scale Josephson junction in which the charging

  7. IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 13, NO. 2, JUNE 2003 989 Banishing Quasiparticles From Josephson-Junction

    E-Print Network [OSTI]

    Lang, Kristine M.

    Quasiparticles From Josephson-Junction Qubits: Why and How to do it K. M. Lang, S. Nam, J. Aumentado, C. Urbina, and John M. Martinis, Member, IEEE Abstract--Current-biased Josephson junctions are prime candidates are effective and that the design of Josephson-junction qubits must consider the role of quasiparticles. Index

  8. SPECTRAL ANALYSIS OF A PHASE LOCKED LASER AT 891 GHz, AN APPLICATION OF JOSEPHSON JUNCTIONS IN THE FAR INFRARED

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    285 SPECTRAL ANALYSIS OF A PHASE LOCKED LASER AT 891 GHz, AN APPLICATION OF JOSEPHSON JUNCTIONS. Abstract. 2014 We have used a Josephson junction to investigate the spectral purity of an HCN laser which take advantage of the unique properties of the Josephson junction as a frequency multiplier and mixer

  9. Coherence transition of small Josephson junctions coupled to a single-mode resonant cavity: Connection to the Dicke model

    E-Print Network [OSTI]

    Stroud, David

    Coherence transition of small Josephson junctions coupled to a single-mode resonant cavity 5 February 2009 PACS: 74.50.+r 74.25.Nf 85.25.Cp 64.60.Cn Keywords: Josephson junctions properties of a collection of N small Josephson junctions coupled to a single-mode resonant electromagnetic

  10. Evidence for triplet superconductivity in Josephson junctions with barriers of the ferromagnetic Heusler alloy Cu2MnAl

    E-Print Network [OSTI]

    Martinis, John M.

    Evidence for triplet superconductivity in Josephson junctions with barriers of the ferromagnetic have studied Josephson junctions with barriers prepared from the Heusler compound Cu2MnAl. In the as metal. Measurements on lateral Josephson junctions with half metallic CrO2 Ref. 7 and the rare

  11. Magnetic flux distribution in a three-dimensional inductive network of Josephson junctions A. Tuohimaa,* J. Paasi, and T. Tarhasaari

    E-Print Network [OSTI]

    Di Matteo, Tiziana

    Magnetic flux distribution in a three-dimensional inductive network of Josephson junctions A received 20 October 1999 The magnetic response of three-dimensional Josephson junction networks to constant made of n elementary cubic cells, each cell containing 12 resistively shunted ideal Josephson junctions

  12. Measurements of 1/f noise in Josephson junctions at zero voltage: Implications for decoherence in superconducting quantum bits

    E-Print Network [OSTI]

    Le Roy, Robert J.

    Measurements of 1/f noise in Josephson junctions at zero voltage: Implications for decoherence box,3,4 "quantronium,"5 and the current-biased Josephson junction.6­8 A major challenge is to identify in capacitive elements and fluctuations in the coupling energy of Josephson junctions, which gives rise

  13. Lithium implantation at low temperature in silicon for sharp buried amorphous layer formation and defect engineering

    SciTech Connect (OSTI)

    Oliviero, E. [CSNSM, CNRS-IN2P3-Universite Paris-Sud, Batiment 108, 91405 Orsay (France); David, M. L.; Beaufort, M. F.; Barbot, J. F. [Institut Pprime, CNRS-Universite de Poitiers-ENSMA, SP2MI, Bd Marie et Pierre Curie, BP30179, 86962 Futuroscope-Chasseneuil Cedex (France); Fichtner, P. F. P. [Departamento de Metalurgia, Universidade Federal do Rio Grande do Sul, Av Bento Goncalves 9500, Caixa Postal 15051, 90035-190 Porto Alegre, RS (Brazil)

    2013-02-28T23:59:59.000Z

    The crystalline-to-amorphous transformation induced by lithium ion implantation at low temperature has been investigated. The resulting damage structure and its thermal evolution have been studied by a combination of Rutherford backscattering spectroscopy channelling (RBS/C) and cross sectional transmission electron microscopy (XTEM). Lithium low-fluence implantation at liquid nitrogen temperature is shown to produce a three layers structure: an amorphous layer surrounded by two highly damaged layers. A thermal treatment at 400 Degree-Sign C leads to the formation of a sharp amorphous/crystalline interfacial transition and defect annihilation of the front heavily damaged layer. After 600 Degree-Sign C annealing, complete recrystallization takes place and no extended defects are left. Anomalous recrystallization rate is observed with different motion velocities of the a/c interfaces and is ascribed to lithium acting as a surfactant. Moreover, the sharp buried amorphous layer is shown to be an efficient sink for interstitials impeding interstitial supersaturation and {l_brace}311{r_brace} defect formation in case of subsequent neon implantation. This study shows that lithium implantation at liquid nitrogen temperature can be suitable to form a sharp buried amorphous layer with a well-defined crystalline front layer, thus having potential applications for defects engineering in the improvement of post-implantation layers quality and for shallow junction formation.

  14. Layered semiconductor neutron detectors

    DOE Patents [OSTI]

    Mao, Samuel S; Perry, Dale L

    2013-12-10T23:59:59.000Z

    Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

  15. Ischemic preconditioning enhances integrity of coronary endothelial tight junctions

    SciTech Connect (OSTI)

    Li, Zhao [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States); Jin, Zhu-Qiu, E-mail: zhu-qiu.jin@sdstate.edu [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States)

    2012-08-31T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer Cardiac tight junctions are present between coronary endothelial cells. Black-Right-Pointing-Pointer Ischemic preconditioning preserves the structural and functional integrity of tight junctions. Black-Right-Pointing-Pointer Myocardial edema is prevented in hearts subjected to ischemic preconditioning. Black-Right-Pointing-Pointer Ischemic preconditioning enhances translocation of ZO-2 from cytosol to cytoskeleton. -- Abstract: Ischemic preconditioning (IPC) is one of the most effective procedures known to protect hearts against ischemia/reperfusion (IR) injury. Tight junction (TJ) barriers occur between coronary endothelial cells. TJs provide barrier function to maintain the homeostasis of the inner environment of tissues. However, the effect of IPC on the structure and function of cardiac TJs remains unknown. We tested the hypothesis that myocardial IR injury ruptures the structure of TJs and impairs endothelial permeability whereas IPC preserves the structural and functional integrity of TJs in the blood-heart barrier. Langendorff hearts from C57BL/6J mice were prepared and perfused with Krebs-Henseleit buffer. Cardiac function, creatine kinase release, and myocardial edema were measured. Cardiac TJ function was evaluated by measuring Evans blue-conjugated albumin (EBA) content in the extravascular compartment of hearts. Expression and translocation of zonula occludens (ZO)-2 in IR and IPC hearts were detected with Western blot. A subset of hearts was processed for the observation of ultra-structure of cardiac TJs with transmission electron microscopy. There were clear TJs between coronary endothelial cells of mouse hearts. IR caused the collapse of TJs whereas IPC sustained the structure of TJs. IR increased extravascular EBA content in the heart and myocardial edema but decreased the expression of ZO-2 in the cytoskeleton. IPC maintained the structure of TJs. Cardiac EBA content and edema were reduced in IPC hearts. IPC enhanced the translocation of ZO-2 from cytosol to cytoskeleton. In conclusion, TJs occur in normal mouse heart. IPC preserves the integrity of TJ structure and function that are vulnerable to IR injury.

  16. Distribution and diversity of fungal species in and adjacent to the Los Alamos National Laboratory

    SciTech Connect (OSTI)

    Balice, R.G.; Jarmie, N.; Rogers, F.J.

    1997-12-01T23:59:59.000Z

    Fungi have demonstrated their ability to diversify and specialize to take advantage of new environments (Murphy 1996). These species are essential to the normal functioning of ecosystems and the impacts of human activities may be harmful to fungi. There is a need to inventory fungi throughout the range of their environments. Previously archived information representing 43 sample locations was used to perform a preliminary evaluation of the distributions and diversity of fungal species at the Los Alamos National Laboratory and in adjacent environments. Presence-absence data for 71 species of fungi in five habitats, pinon-juniper, canyon-bottom ponderosa pine, ponderosa pine, canyon-bottom mixed conifer, and mixed conifer were analyzed. The results indicate that even though fungi occur in each of the habitats, fungal species are not distributed evenly among these habitats. The richness of fungal species is greater in the canyon-bottom mixed conifer and mixed conifer habitats than in the pinon-juniper, canyon-bottom ponderosa pine or ponderosa pine habitats. All but three of the fungal species were recorded in either the canyon-bottom mixed conifer or the mixed conifer habitats, and all but seven of the fungal species were found in the mixed conifer habitat.

  17. Classical resonance interactions and Josephson junction in macroscopic quantum dynamics

    E-Print Network [OSTI]

    Pilipchuk, V N

    2012-01-01T23:59:59.000Z

    It is shown that the classical dynamics of 1:1 resonance interaction between two identical linearly coupled Duffing oscillators is equivalent to the symmetric (non-biased) case of `macroscopic' quantum dynamics of two weakly coupled Bose-Einstein condensates. The analogy develops through the boson Josephson junction equations, however, reduced to a single conservative energy partition (EP) oscillator. The derived oscillator is solvable in quadratures, furthermore it admits asymptotic solution in terms of elementary functions after transition to the action-angle variables. Energy partition and coherency indexes are introduced to provide a complete characterization of the system dynamic states through the state variables of the EP oscillator. In particular, nonlinear normal and local mode dynamics of the original system associate with equilibrium points of such oscillator. Additional equilibrium points - the local modes - may occur on high energy level as a result of the symmetry breaking bifurcation, which is ...

  18. Mean Field Theory of Josephson Junction Arrays with Charge Frustration

    E-Print Network [OSTI]

    G. Grignani; A. Mattoni; P. Sodano; A. Trombettoni

    1999-02-12T23:59:59.000Z

    Using the path integral approach, we provide an explicit derivation of the equation for the phase boundary for quantum Josephson junction arrays with offset charges and non-diagonal capacitance matrix. For the model with nearest neighbor capacitance matrix and uniform offset charge $q/2e=1/2$, we determine, in the low critical temperature expansion, the most relevant contributions to the equation for the phase boundary. We explicitly construct the charge distributions on the lattice corresponding to the lowest energies. We find a reentrant behavior even with a short ranged interaction. A merit of the path integral approach is that it allows to provide an elegant derivation of the Ginzburg-Landau free energy for a general model with charge frustration and non-diagonal capacitance matrix. The partition function factorizes as a product of a topological term, depending only on a set of integers, and a non-topological one, which is explicitly evaluated.

  19. A bosonic Josephson junction controlled by a single trapped ion

    E-Print Network [OSTI]

    Gerritsma, R; Doerk, H; Idziaszek, Z; Calarco, T; Schmidt-Kaler, F

    2011-01-01T23:59:59.000Z

    We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion. We find that the coupling between the wells can be controlled by the internal state of the ion, which can be used for studying mesoscopic entanglement between the two systems and to measure their interaction with high precision. As a particular example we consider a small $^{87}$Rb Bose-Einstein condensate controlled by a single $^{171}$Yb$^+$ ion. We calculate interwell coupling rates reaching 100 Hz, while the state dependence amounts to 10s of Hz for plausible values of the currently unknown s-wave scattering length between the atom and the ion. The system could be realized in an experiment by combining trapped ions with optical dipole traps for cold atoms or in a combined atom-ion micro trap, where both approaches are within reach using current technology.

  20. Dissipative Nonlinear Josephson Junction of Optical Soliton and Surface Plasmon

    E-Print Network [OSTI]

    Ek?io?lu, Yasa; Güven, Kaan

    2012-01-01T23:59:59.000Z

    We examine the dynamics of a dissipative photonic Josephson junction formed by the weak coupling of an optical soliton in a nonlinear dielectric waveguide and a co-propagating surface plasmon along a parallel metal surface with a linear dielectric spacer. We employ a heuristic model with a coupling function that depends on the soliton amplitude, and consider two phenomenological dissipation mechanisms separately: angular velocity dissipation and population imbalance dissipation. In the former dissipation mechanism, the system exhibits phase-slip phenomenon where the odd-\\pi phase modes decay into even-\\pi phase modes. The latter damping mechanism sculptures the phase-space significantly by introducing complex features, among which Hopf type bifurcations are notable. We show that some of the bifurcation points expand to stable limit cycles for certain regimes of the model parameters.

  1. A bosonic Josephson junction controlled by a single trapped ion

    E-Print Network [OSTI]

    R. Gerritsma; A. Negretti; H. Doerk; Z. Idziaszek; T. Calarco; F. Schmidt-Kaler

    2012-07-25T23:59:59.000Z

    We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion. We find that the coupling between the wells can be controlled by the internal state of the ion, which can be used for studying mesoscopic entanglement between the two systems and to measure their interaction with high precision. As a particular example we consider a single $^{87}$Rb atom and a small Bose-Einstein condensate controlled by a single $^{171}$Yb$^+$ ion. We calculate inter-well coupling rates reaching hundreds of Hz, while the state dependence amounts to tens of Hz for plausible values of the currently unknown s-wave scattering length between the atom and the ion. The analysis shows that it is possible to induce either the self-trapping or the tunneling regime, depending on the internal state of the ion. This enables the generation of large scale ion-atomic wavepacket entanglement within current technology.

  2. Noise Effects on birhythmic Josephson Junction coupled to a Resonator

    E-Print Network [OSTI]

    R. Yamapi; G. Filatrella

    2014-06-24T23:59:59.000Z

    We study the effect of noise on a Josephson junction that, coupled to a linear $RLC$ resonator, can oscillate at two frequencies. To establish the global stability of the attractors, we estimate the position of the separatrix, an essential information to establish the stability of the attractor for this multidimensional system, from the analysis of the mean first passage time. We find that the frequency locked to the resonator is most stable at low bias, and less stable at high bias, where the resonator exhibits the largest oscillations. The change in the birhythmic region is dramatic, for the effective barrier changes of an order of magnitude and the corresponding lifetime of about seven decades.

  3. Joule heating generated by spin current through Josephson junctions

    SciTech Connect (OSTI)

    Takahashi, S.; Yamashita, T.; Koyama, T.; Maekawa, S.; Imamura, H.

    2001-06-01T23:59:59.000Z

    We theoretically study the spin-polarized current flowing through a Josephson junction (JJ) in a spin injection device. When the spin-polarized current is injected from a ferromagnet in a superconductor (SC), the charge current is carried by the superconducting condensate (Cooper pairs), while the spin-up and spin-down currents flow in equal magnitude but in the opposite direction in a SC, because of no quasiparticle charge current in the SC. This indicates that not only the Josephson current but also the spin current flow across JJ at zero bias voltage, thereby generating Joule heating by the spin current. The result provides a new method for detecting the spin current by measuring Joule heating at JJ. {copyright} 2001 American Institute of Physics.

  4. False qubits?: Polarization of light and Josephson junction

    E-Print Network [OSTI]

    Robert Alicki

    2006-11-29T23:59:59.000Z

    We compare two physical systems: polarization degrees of freedom of a macroscopic light beam and the Josephson junction (JJ) in the "charge qubit regime". The first system obviously cannot carry genuine quantum information and we show that the maximal entanglement which could be encoded into polarization of two light beams scales like 1/(photon number). Two theories of JJ, one leading to the picture of "JJ-qubit" and the other based on the mean-field approach are discussed. The later, which seems to be more appropriate, implies that the JJ system is, essentially, mathematically equivalent to the polarization of a light beam with the number of photons replaced by the number of Cooper pairs. The existing experiments consistent with the "JJ-qubit" picture and the theoretical arguments supporting, on the contrary, the classical model are briefly discussed. The Franck-Hertz-type experiment is suggested as an ultimate test of the JJ nature.

  5. Nonequilibrium Transitions in Fully Frustrated Josephson Junction Arrays

    SciTech Connect (OSTI)

    Marconi, Veronica I.; Dominguez, Daniel

    2001-07-02T23:59:59.000Z

    We study the effect of thermal fluctuations in a fully frustrated Josephson junction array driven by a current I larger than the apparent critical current I{sub c}(T) . We calculate numerically the behavior of the chiral order parameter of Z{sub 2} symmetry and the transverse helicity modulus [related to the U(1) symmetry] as a function of temperature. We find that the Z{sub 2} transition occurs at a temperature T{sub Z{sub 2}}(I) which is lower than the temperature T{sub U(1)}(I) for the U(1) transition. Both transitions could be observed experimentally from measurements of the longitudinal and transverse voltages.

  6. Method and Apparatus for Remote Delivery and Manipulation of a Miniature Tool Adjacent a Work Piece in a Restricted Space

    DOE Patents [OSTI]

    Sale, Christopher H.; Kaltenbaugh, Daniel R.

    2004-08-10T23:59:59.000Z

    An apparatus for remote delivery and manipulation of a miniature tool adjacent a work piece in a restricted space, includes a tool camer, a camage for manipulating the tool carrier relative to the work piece, a first actuator for operating the carnage, and an optional remote secondary operating actuator for operating the first actuator.

  7. VASCULAR PLANTS OF ADJACENT SERPENTINE AND GRANITE OUTCROPS ON THE DEER ISLES, MAINE, U.S.A.

    E-Print Network [OSTI]

    Rajakaruna, Nishanta

    VASCULAR PLANTS OF ADJACENT SERPENTINE AND GRANITE OUTCROPS ON THE DEER ISLES, MAINE, U study of the vascular flora of a serpentine outcrop, Pine Hill, and that of a granite outcrop from serpentine and 89 from granite. Fifty-seven taxa were shared by both sites. Species richness (a

  8. Spatial relationships between nitrogen status and pitch canker disease in slash pine planted adjacent to a poultry operation

    E-Print Network [OSTI]

    Grunwald, Sabine

    adjacent to a poultry operation Isabel Lopez-Zamora a , Christine Bliss a , Eric J. Jokela b,*, N June 2006; accepted 18 August 2006 Local emissions from poultry production appear to significantly to nutrient imbalances. Poultry houses with forced-air ventilation systems produce nitrogen (N) emissions

  9. Synchronization of a Josephson junction array in terms of global variables

    E-Print Network [OSTI]

    Vladimir Vlasov; Arkady Pikovsky

    2013-04-08T23:59:59.000Z

    We consider an array of Josephson junctions with a common LCR-load. Application of the Watanabe-Strogatz approach [Physica D, v. 74, p. 197 (1994)] allows us to formulate the dynamics of the array via the global variables only. For identical junctions this is a finite set of equations, analysis of which reveals the regions of bistability of the synchronous and asynchronous states. For disordered arrays with distributed parameters of the junctions, the problem is formulated as an integro-differential equation for the global variables, here stability of the asynchronous states and the properties of the transition synchrony-asynchrony are established numerically.

  10. Magnetic vortices in a distributed Josephson junction with electrodes of finite thickness

    SciTech Connect (OSTI)

    Alfimov, G.L.; Popkov, A.F. [F. V. Lukin`s Research Institute of Physicsl Problems, Zelenograd, Moscow, 103460 (Russian Federation)] [F. V. Lukin`s Research Institute of Physicsl Problems, Zelenograd, Moscow, 103460 (Russian Federation)

    1995-08-01T23:59:59.000Z

    A distributed Josephson junction with electrodes of finite thickness is considered in the case of high critical current density when the Josephson penetration depth {lambda}{sub {ital j}} is less than the London depth {lambda}{sub {ital L}}. A nonlinear nonlocal equation for steady-state distributions of phase difference {ital cphi} across the junction is derived. In the asymptotical case of thin electrodes an exact nonlinear solution for this equation which corresponds to an isolated at-rest Josephson vortex is found. A numerical investigation of the equation derived is carried out and some static and dynamic characteristics of vortices in such a Josephson junction are represented.

  11. A Controllable Interaction between Two-Level Systems inside a Josephson Junction

    E-Print Network [OSTI]

    L. Tian; K. Jacobs

    2009-03-23T23:59:59.000Z

    Two-level system fluctuators (TLS's) in the tunnel barrier of a Josephson junction have recently been demonstrated to cause novel energy splittings in spectroscopic measurements of superconducting phase qubits. With their strong coupling to the Josephson junction and relatively long decoherence times, TLS's can be considered as potential qubits and demonstrate coherent quantum effects. Here, we study the effective interaction between the TLS qubits that is mediated by a Josephson junction resonator driven by an external microwave source. This effective interaction can enable controlled quantum logic gates between the TLS's. Our study can be extended to other superconducting resonators coupling with TLS's.

  12. Dissipative Dynamics of a Josephson Junction In the Bose-Gases

    E-Print Network [OSTI]

    R. A. Barankov; S. N. Burmistrov

    2003-01-09T23:59:59.000Z

    The dissipative dynamics of a Josephson junction in the Bose-gases is considered within the framework of the model of a tunneling Hamiltonian. The effective action which describes the dynamics of the phase difference across the junction is derived using functional integration method. The dynamic equation obtained for the phase difference across the junction is analyzed for the finite temperatures in the low frequency limit involving the radiation terms. The asymmetric case of the Bose-gases with the different order parameters is calculated as well.

  13. Pinning-modulated non-collective Josephson-vortex motion in stacked Josephson junctions.

    SciTech Connect (OSTI)

    Jin, Y.-D.; Lee, G.-H.; Lee, H.-J.; Bae, M.-H.; Koshelev, A. E.; Pohang Univ. of Science and Technology; Univ. of Illinois

    2009-01-01T23:59:59.000Z

    Josephson vortices in naturally stacked Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} tunneling junctions display rich dynamic behavior that derives from the coexistence of three basic states: static Josephson vortex lattice, coherently moving lattice, and incoherent quasiparticle tunneling state. The rich structure of hysteretic branches observed in the current-voltage characteristics can be understood as combinatorial combinations of these three states which are realized in different junctions and evolve separately with magnetic field and bias current. In particular, the multiple Josephson vortex flow branches at low-bias currents arise from the individual depinning of Josephson vortex rows in each junction.

  14. IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS--II: EXPRESS BRIEFS, VOL. 53, NO. 10, OCTOBER 2006 1031 Spiking and Bursting in Josephson Junction

    E-Print Network [OSTI]

    Spiking and Bursting in Josephson Junction Syamal Kumar Dana, Member, IEEE, Dipendra Chandra Sengupta of the resistive­capacitive­inductive shunted Josephson junction model. Regular spiking, intrinsic bursting--Bursting, Josephson junction, neuron, spiking. I. INTRODUCTION THE DYNAMICS of the Josephson junction under an ex

  15. Aberration-corrected transmission electron microscopy analyses of GaAs/Si interfaces in wafer-bonded multi-junction solar cells

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    -bonded multi-junction solar cells Dietrich Häussler a , Lothar Houben b , Stephanie Essig c , Mert Kurttepeli online 20 July 2013 Keywords: Multi-junction solar cell Wafer bonding Interfaces Aberration corrected and composition fluctuations near interfaces in wafer-bonded multi-junction solar cells. Multi-junction solar

  16. Engineering electroresponsive layer-by-layer thin films

    E-Print Network [OSTI]

    Schmidt, Daniel J., Ph. D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    Electroresponsive layer-by-layer (LbL) polymer films and polymer nanocomposite films were investigated as model systems for electrically triggered drug delivery applications and "mechanomutable" surface coating applications. ...

  17. Ion transport and structure of layer-by-layer assemblies

    E-Print Network [OSTI]

    Lutkenhaus, Jodie Lee

    2007-01-01T23:59:59.000Z

    Layer-by-layer (LbL) films of various architectures were examined as potential solid state electrolytes for electrochemical systems (e.g. batteries and fuel cells). The relationship between materials properties and ion ...

  18. Layer-by-layer assembly in confined geometries

    E-Print Network [OSTI]

    DeRocher, Jonathan P

    2011-01-01T23:59:59.000Z

    The fundamental nature of layer-by-layer (LbL) assembly in confined geometries was investigated for a number of different chemical systems. The first part of this thesis concerns the modification of microfluidic and ...

  19. Formation of Porous Layers by Electrochemical Etching of Germanium and Gallium Arsenide for Cleave Engineered Layer Transfer (CELT) Application in High Efficiency Multi-Junction Solar Cells

    E-Print Network [OSTI]

    Fong, David Michael

    2012-01-01T23:59:59.000Z

    film photovoltaics [1]. This roughly doubling of efficiencyMJ photovoltaics. MJ solar cells achieve higher efficiencies

  20. Temperature study of Zero Bias Features using self-assembling tunnel junctions

    E-Print Network [OSTI]

    Savitski, Stephen Ronald

    2012-06-07T23:59:59.000Z

    The significant reduction in the conductance of a tunneling system near zero bias voltage is termed the Zero Bias Feature (ZBF). A ³He cryostat has been modified to incorporate a Self-Assembling Tunnel Junction (SATJ), capable of performing...

  1. Back to the crossroads of Flatbush--the junction--student housing for Brooklyn College

    E-Print Network [OSTI]

    Campbell, Keith A. (Keith Anthony)

    1988-01-01T23:59:59.000Z

    The crossroads of Flatbush (often called The Junction) is a five point intersection of vehicular and pedestrian traffic. A crossroad where ethnic groups step beyond subtle neighborhood boundaries and merge to use public ...

  2. E-Print Network 3.0 - alkanedithiol single-molecule junctions...

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

    electrodes to form a metal-molecule- metal junction. Alkanedithiols with 5, 6, 8 and 9 carbon atoms were... mode). As there are no clear multiples of the GA and GB, GC seems to...

  3. Eigenstates of a Small Josephson Junction Coupled to a Resonant Cavity

    E-Print Network [OSTI]

    W. A. Al-Saidi; D. Stroud

    2001-10-05T23:59:59.000Z

    We carry out a quantum-mechanical analysis of a small Josephson junction coupled to a single-mode resonant cavity. We find that the eigenstates of the combined junction-cavity system are strongly entangled only when the gate voltage applied at one of the superconducting islands is tuned to certain special values. One such value corresponds to the resonant absorption of a single photon by Cooper pairs in the junction. Another special value corresponds to a {\\em two-photon} absorption process. Near the single-photon resonant absorption, the system is accurately described by a simplified model in which only the lowest two levels of the Josephson junction are retained in the Hamiltonian matrix. We noticed that this approximation does not work very well as the number of photons in the resonator increases. Our system shows also the phenomenon of ``collapse and revival'' under suitable initial conditions, and our full numerical solution agrees with the two level approximation result.

  4. E-Print Network 3.0 - atypical adherens junction Sample Search...

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

    search results for: atypical adherens junction Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: and Is Required for Adherens...

  5. E-Print Network 3.0 - adherens junction formation Sample Search...

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

    search results for: adherens junction formation Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: and Is Required for Adherens...

  6. E-Print Network 3.0 - adherens junction integrity Sample Search...

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

    search results for: adherens junction integrity Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: suggest that DLG-1 might be...

  7. E-Print Network 3.0 - adherens junctions remain Sample Search...

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

    search results for: adherens junctions remain Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: and Is Required for Adherens...

  8. E-Print Network 3.0 - adherens junctions connect Sample Search...

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

    search results for: adherens junctions connect Page: << < 1 2 3 4 5 > >> 1 Molecular Biology of the Cell Vol. 12, 34653475, November 2001 Summary: and Is Required for Adherens...

  9. E-Print Network 3.0 - apical junction proteins Sample Search...

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

    for: apical junction proteins Page: << < 1 2 3 4 5 > >> 1 MOLECULAR AND CELLULAR BIOLOGY, Jan. 2011, p. 8191 Vol. 31, No. 1 0270-73061112.00 doi:10.1128MCB.01001-10...

  10. Resonant escape over an oscillating barrier in underdamped Josephson tunnel junctions

    E-Print Network [OSTI]

    Han, Siyuan; Yu, Yang

    2003-09-01T23:59:59.000Z

    The escape from a metastable state over an oscillating barrier of an underdamped Josephson tunnel junction has been experimentally investigated with oscillation frequency well separated from the plasma frequency of the ...

  11. Grain boundary and triple junction constraints during martensitic transformation in shape memory alloys

    E-Print Network [OSTI]

    Ueland, Stian Melhus

    We investigate the role of grain constraint upon martensitic transformation through in situ scanning electron microscope tensile experiments on shape memory microwires with a small number of grains and grain junctions. The ...

  12. Competition between cotunneling, Kondo effect, and direct tunneling in discontinuous high-anisotropy magnetic tunnel junctions

    E-Print Network [OSTI]

    Ciudad, David

    The transition between Kondo and Coulomb blockade effects in discontinuous double magnetic tunnel junctions is explored as a function of the size of the CoPt magnetic clusters embedded between AlO[subscript x] tunnel ...

  13. Design of a scanning Josephson junction microscope for submicron-resolution magnetic imaging

    SciTech Connect (OSTI)

    Plourde, B.L.; Van Harlingen, D.J. [Department of Physics, Science and Technology Center for Superconductivity, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)] [Department of Physics, Science and Technology Center for Superconductivity, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    1999-11-01T23:59:59.000Z

    We describe a magnetic field scanning instrument designed to extend the spatial resolution of scanning superconducting quantum interference device microscopy into the submicron regime. This instrument, the scanning Josephson junction microscope, scans a single Josephson junction across the surface of a sample, detecting the local magnetic field by the modulation of the junction critical current. By using a submicron junction and a scanning tunneling microscope feedback system to maintain close proximity to the surface, magnetic field sensitivity of 10 {mu}G with a spatial resolution of 0.3 {mu}m should be attainable, opening up new opportunities for imaging vortex configurations and core structure in superconductors and magnetic domains in magnetic materials. {copyright} {ital 1999 American Institute of Physics.}

  14. 0.7-eV GaInAs Junction for a GaInP/GaAs/GaInAs(1eV)/GaInAs(0.7eV) Four-Junction Solar Cell

    SciTech Connect (OSTI)

    Friedman, D. J.; Geisz, J. F.; Norman, A. G.; Wanlass, M. W.; Kurtz, S. R.

    2006-01-01T23:59:59.000Z

    We discuss recent developments in III-V multijunction solar cells, focusing on adding a fourth junction to the Ga{sub 0.5}In{sub 0.5} P/GaAs/Ga{sub 0.75}In{sub 0.25}As inverted three-junction cell. This cell, grown inverted on GaAs so that the lattice-mismatched Ga{sub 0.75}In{sub 0.25}As third junction is the last one grown, has demonstrated 38% efficiency, and 40% is likely in the near future. To achieve still further gains, a lower-bandgap Ga{sub x}In{sub 1-x}As fourth junction could be added to the three-junction structure for a four-junction cell whose efficiency could exceed 45% under concentration. Here, we present the initial development of the Ga{sub x}In{sub 1-x}As fourth junction. Junctions of various bandgaps ranging from 0.88 to 0.73 eV were grown, in order to study the effect of the different amounts of lattice mismatch. At a bandgap of 0.88 eV, junctions were obtained with very encouraging {approx}80% quantum efficiency, 57% fill factor, and 0.36 eV open-circuit voltage. The device performance degrades with decreasing bandgap (i.e., increasing lattice mismatch). We model the four-junction device efficiency vs. fourth junction bandgap to show that an 0.7-eV fourth-junction bandgap, while optimal if it could be achieved in practice, is not necessary; an 0.9-eV bandgap would still permit significant gains in multijunction cell efficiency while being easier to achieve than the lower-bandgap junction.

  15. Quantum Robust Stability of a Small Josephson Junction in a Resonant Cavity

    E-Print Network [OSTI]

    Ian R. Petersen

    2013-01-09T23:59:59.000Z

    This paper applies recent results on the robust stability of nonlinear quantum systems to the case of a Josephson junction in a resonant cavity. The Josephson junction is characterized by a Hamiltonian operator which contains a non-quadratic term involving a cosine function. This leads to a sector bounded nonlinearity which enables the previously developed theory to be applied to this system in order to analyze its stability.

  16. Single-junction solar cells with the optimum band gap for terrestrial concentrator applications

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    1994-01-01T23:59:59.000Z

    A single-junction solar cell having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of "pinning" the optimum band gap for a wide range of operating conditions at a value of 1.14.+-.0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap.

  17. Studies of chaos and thermal noise in a driven Josephson junction using an electronic analog

    SciTech Connect (OSTI)

    Pegrum, C.M.; Gurney, W.S.C.; Nisbet, R.M.

    1989-03-01T23:59:59.000Z

    Using an electronic analog of a resistively shunted driven Josephson junction, the authors have demonstrated a number of effects, including the appearance of a devil's staircase in the current-voltage characteristic, the onset of chaos, and the effect of noise on these phenomena. The authors stress that the analog is simple, but models the junction behavior with a high degree of accuracy and detail.

  18. Growth and electrical rectification in axial in-situ doped p-n junction germanium nanowires

    SciTech Connect (OSTI)

    Picraux, Samuel T [Los Alamos National Laboratory; Dayeh, Shadi [Los Alamos National Laboratory; Zaslavsky, Alexander [BROWN U; Le, Son T [BROWN U

    2009-01-01T23:59:59.000Z

    In this work, we demonstrate the vapor-liquid-solid (VLS) growth and electrical properties of axial in-situ doped p-n junction Ge nanowires (NWs). In-situ doping of the NWs was accomplished by introducing dopant gases (diborane and phosphine) together with GeH{sub 4} in the growth process. By changing dopant sources during growth, a p-n junction can be realized along the axis of the NWs. Metal contacts to the wires were defined using e-beam lithography patterning, followed by 100 nm Ni sputter deposition and lift-off. Four-point measurements of the fabricated devices at room temperature and at 77 K clearly show rectification with on/off current ratio up to two orders of magnitude when the bias is applied across the p-n junction. The ideality factor of the junction current points to a significant generation-recombination contribution. The Ohmic characteristics in the p and n regions outside the junction make it possible to estimate the doping levels. We also observed backgate control of the NW junction current.

  19. Spin Josephson effect in topological superconductor-ferromagnet junction

    SciTech Connect (OSTI)

    Ren, C. D.; Wang, J., E-mail: jwang@seu.edu.cn [Department of Physics, Southeast University, Nanjing 210096 (China)

    2014-03-21T23:59:59.000Z

    The composite topological superconductor (TS), made of one-dimensional spin-orbit coupled nanowire with proximity-induced s-wave superconductivity, is not a pure p-wave superconductor but still has a suppressed s-wave pairing. We propose to probe the spin texture of the p-wave pairing in this composite TS by examining possible spin supercurrents in an unbiased TS/ferromagnet junction. It is found that both the exchange-coupling induced and spin-flip reflection induced spin currents exist in the setup and survive even in the topological phase. We showed that besides the nontrivial p-wave pairing state accounting for Majorana Fermions, there shall be a trivial p-wave pairing state that contributes to spin supercurrent. The trivial p-wave pairing state is diagnosed from the mixing effect between the suppressed s-wave pairing and the topologically nontrivial p-wave pairing. The d vector of the TS is proved not to be rigorously perpendicular to the spin projection of p-wave pairings. Our findings are also confirmed by the Kitaev's p-wave model with a nonzero s-wave pairing.

  20. Quantum interference in thermoelectric molecular junctions: A toy model perspective

    SciTech Connect (OSTI)

    Nozaki, Daijiro, E-mail: daijiro.nozaki@gmail.com, E-mail: research@nano.tu-dresden.de [Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Avdoshenko, Stas M. [Department of Chemistry and Institute for Computational Engineering and Sciences, University of Texas at Austin, 100 E. 24th St. A1590, Austin, Texas 78712 (United States); Sevinçli, Hâldun [Department of Materials Science and Engineering, Izmir Institute of Technology, Gulbahce Kampusu 35430 Urla, Izmir (Turkey); Cuniberti, Gianaurelio [Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Dresden Center for Computational Materials Science (DCCMS), TU Dresden, 01062 Dresden (Germany); Center for Advancing Electronics Dresden (cfAED), TU Dresden, 01062 Dresden (Germany)

    2014-08-21T23:59:59.000Z

    Quantum interference (QI) phenomena between electronic states in molecular circuits offer a new opportunity to design new types of molecular devices such as molecular sensors, interferometers, and thermoelectric devices. Controlling the QI effect is a key challenge for such applications. For the development of single molecular devices employing QI effects, a systematic study of the relationship between electronic structure and the quantum interference is needed. In order to uncover the essential topological requirements for the appearance of QI effects and the relationship between the QI-affected line shape of the transmission spectra and the electronic structures, we consider a homogeneous toy model where all on-site energies are identical and model four types of molecular junctions due to their topological connectivities. We systematically analyze their transmission spectra, density of states, and thermoelectric properties. Even without the degree of freedom for on-site energies an asymmetric Fano peak could be realized in the homogeneous systems with the cyclic configuration. We also calculate the thermoelectric properties of the model systems with and without fluctuation of on-site energies. Even under the fluctuation of the on-site energies, the finite thermoelectrics are preserved for the Fano resonance, thus cyclic configuration is promising for thermoelectric applications. This result also suggests the possibility to detect the cyclic configuration in the homogeneous systems and the presence of the QI features from thermoelectric measurements.

  1. Computational Fluid Dynamics Analysis of Flexible Duct Junction Box Design

    SciTech Connect (OSTI)

    Beach, R.; Prahl, D.; Lange, R.

    2013-12-01T23:59:59.000Z

    IBACOS explored the relationships between pressure and physical configurations of flexible duct junction boxes by using computational fluid dynamics (CFD) simulations to predict individual box parameters and total system pressure, thereby ensuring improved HVAC performance. Current Air Conditioning Contractors of America (ACCA) guidance (Group 11, Appendix 3, ACCA Manual D, Rutkowski 2009) allows for unconstrained variation in the number of takeoffs, box sizes, and takeoff locations. The only variables currently used in selecting an equivalent length (EL) are velocity of air in the duct and friction rate, given the first takeoff is located at least twice its diameter away from the inlet. This condition does not account for other factors impacting pressure loss across these types of fittings. For each simulation, the IBACOS team converted pressure loss within a box to an EL to compare variation in ACCA Manual D guidance to the simulated variation. IBACOS chose cases to represent flows reasonably correlating to flows typically encountered in the field and analyzed differences in total pressure due to increases in number and location of takeoffs, box dimensions, and velocity of air, and whether an entrance fitting is included. The team also calculated additional balancing losses for all cases due to discrepancies between intended outlet flows and natural flow splits created by the fitting. In certain asymmetrical cases, the balancing losses were significantly higher than symmetrical cases where the natural splits were close to the targets. Thus, IBACOS has shown additional design constraints that can ensure better system performance.

  2. Investigation of redox processes at semiconductor electrode liquid junctions

    SciTech Connect (OSTI)

    Koval, C.A.

    1990-08-01T23:59:59.000Z

    Research in fundamental aspects of photoelectrochemical cells has been in the following areas: chemical probes for hot carrier processes, electrostatic theory for describing electrical interactions at interfaces, and kinetics of electron transfer at ideal semiconductor solution interfaces. Our goal is to achieve a better understanding of dark and photo-induced current flow at the semiconductor electrode/redox electrolyte interface (SEI) so that devices and processes utilizing this interface for solar energy conversion can be developed or improved. Our most important accomplishment has been the development of a redox system capable of detecting hot electrons at the p-InP/acetonitrile interface. Also, we have examined electrostatic theory for the image potential of an ion as a function of distance from the SEI. Finally, our group was one of the first to realize that the 2-dimensional metal chalcogenides (MC) are excellent materials for fundamental studies of electron transfer at the SEI. One of the chief potential advantages for use of MC's is the formation of semiconductor/liquid junctions with nearly ideal electrochemical properties. 27 refs., 1 fig.

  3. Cleanup Verification Package for the 118-F-8:4 Fuel Storage Basin West Side Adjacent and Side Slope Soils

    SciTech Connect (OSTI)

    L. D. Habel

    2008-03-18T23:59:59.000Z

    This cleanup verification package documents completion of remedial action, sampling activities, and compliance with cleanup criteria for the 118-F-8:4 Fuel Storage Basin West Side Adjacent and Side Slope Soils. The rectangular-shaped concrete basin on the south side of the 105-F Reactor building served as an underwater collection, storage, and transfer facility for irradiated fuel elements discharged from the reactor.

  4. Metal deposition using seed layers

    DOE Patents [OSTI]

    Feng, Hsein-Ping; Chen, Gang; Bo, Yu; Ren, Zhifeng; Chen, Shuo; Poudel, Bed

    2013-11-12T23:59:59.000Z

    Methods of forming a conductive metal layers on substrates are disclosed which employ a seed layer to enhance bonding, especially to smooth, low-roughness or hydrophobic substrates. In one aspect of the invention, the seed layer can be formed by applying nanoparticles onto a surface of the substrate; and the metallization is achieved by electroplating an electrically conducting metal onto the seed layer, whereby the nanoparticles serve as nucleation sites for metal deposition. In another approach, the seed layer can be formed by a self-assembling linker material, such as a sulfur-containing silane material.

  5. Buried oxide layer in silicon

    DOE Patents [OSTI]

    Sadana, Devendra Kumar (Pleasantville, NY); Holland, Orin Wayne (Lenoir, TN)

    2001-01-01T23:59:59.000Z

    A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

  6. Quantum Terahertz Electrodynamics and Macroscopic Quantum Tunneling in Layered Superconductors

    E-Print Network [OSTI]

    Nori, Franco

    of macroscopic quantum tunneling (MQT) in stacks of intrinsic Josephson junctions. Because of the long numbers: 74.72.Hs, 74.78.Fk The recent surge of interest in stacks of intrinsic Josephson junctions of stacks of Josephson junctions in quantum electronics [6]. This requires a quantum theory capable

  7. The effect of averaging adjacent planes for artifact reduction in matrix inversion tomosynthesis

    SciTech Connect (OSTI)

    Godfrey, Devon J. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Page McAdams, H. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Dobbins, James T. III [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Department of Biomedical Engineering, Department of Physics, and Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States)

    2013-02-15T23:59:59.000Z

    Purpose: Matrix inversion tomosynthesis (MITS) uses linear systems theory and knowledge of the imaging geometry to remove tomographic blur that is present in conventional backprojection tomosynthesis reconstructions, leaving in-plane detail rendered clearly. The use of partial-pixel interpolation during the backprojection process introduces imprecision in the MITS modeling of tomographic blur, and creates low-contrast artifacts in some MITS planes. This paper examines the use of MITS slabs, created by averaging several adjacent MITS planes, as a method for suppressing partial-pixel artifacts. Methods: Human chest tomosynthesis projection data, acquired as part of an IRB-approved pilot study, were used to generate MITS planes, three-plane MITS slabs (MITSa3), five-plane MITS slabs (MITSa5), and seven-plane MITS slabs (MITSa7). These were qualitatively examined for partial-pixel artifacts and the visibility of normal and abnormal anatomy. Additionally, small (5 mm) subtle pulmonary nodules were simulated and digitally superimposed upon human chest tomosynthesis projection images, and their visibility was qualitatively assessed in the different reconstruction techniques. Simulated images of a thin wire were used to generate modulation transfer function (MTF) and slice-sensitivity profile curves for the different MITS and MITS slab techniques, and these were examined for indications of partial-pixel artifacts and frequency response uniformity. Finally, mean-subtracted, exposure-normalized noise power spectra (ENNPS) estimates were computed and compared for MITS and MITS slab reconstructions, generated from 10 sets of tomosynthesis projection data of an acrylic slab. The simulated in-plane MTF response of each technique was also combined with the square root of the ENNPS estimate to yield stochastic signal-to-noise ratio (SNR) information about the different reconstruction techniques. Results: For scan angles of 20 Degree-Sign and 5 mm plane separation, seven MITS planes must be averaged to sufficiently remove partial-pixel artifacts. MITSa7 does appear to subtly reduce the contrast of high-frequency 'edge' information, but the removal of partial-pixel artifacts makes the appearance of low-contrast, fine-detail anatomy even more conspicuous in MITSa7 slices. MITSa7 also appears to render simulated subtle 5 mm pulmonary nodules with greater visibility than MITS alone, in both the open lung and regions overlying the mediastinum. Finally, the MITSa7 technique reduces stochastic image variance, though the in-plane stochastic SNR (for very thin objects which do not span multiple MITS planes) is only improved at spatial frequencies between 0.05 and 0.20 cycles/mm. Conclusions: The MITSa7 method is an improvement over traditional single-plane MITS for thoracic imaging and the pulmonary nodule detection task, and thus the authors plan to use the MITSa7 approach for all future MITS research at the authors' institution.

  8. Multijunction photovoltaic device and fabrication method

    DOE Patents [OSTI]

    Arya, Rajeewa R. (Jamison, PA); Catalano, Anthony W. (Furlong, PA)

    1993-09-21T23:59:59.000Z

    A multijunction photovoltaic device includes first and second amorphous silicon PIN photovoltaic cells in a stacked arrangement. An interface layer, composed of a doped silicon compound, is disposed between the two cells and has a lower bandgap than the respective n- and p-type adjacent layers of the first and second cells. The interface layer forms an ohmic contact with the one or the adjacent cell layers of the same conductivity type, and a tunnel junction with the other of the adjacent cell layers. The disclosed device is fabricated by a glow discharge process.

  9. Investigation of Junction Properties of CdS/CdTe Solar Cells and their Correlation to Device Properties (Presentation)

    SciTech Connect (OSTI)

    Dhere, R. G.; Zhang, Y.; Romero, M. J.; Asher, S. E.; Young, M.; To, B.; Noufi, R.; Gessert, T. A.

    2008-05-01T23:59:59.000Z

    The objective of the Junction Studies are: (1) understand the nature of the junction in the CdTe/CdS device; (2) correlate the device fabrication parameters to the junction formation; and (3) develop a self consistent device model to explain the device properties. Detailed analysis of CdS/CdTe and SnO{sub 2}/CdTe devices prepared using CSS CdTe is discussed.

  10. Junction Evolution During Fabrication of CdS/CdTe Thin-film PV Solar Cells (Presentation)

    SciTech Connect (OSTI)

    Gessert, T. A.

    2010-09-01T23:59:59.000Z

    Discussion of the formation of CdTe thin-film PV junctions and optimization of CdTe thin-film PV solar cells.

  11. Method of junction formation for CIGS photovoltaic devices

    DOE Patents [OSTI]

    Delahoy, Alan E. (Rocky Hill, NJ)

    2010-01-26T23:59:59.000Z

    Sulfur is used to improve the performance of CIGS devices prepared by the evaporation of a single source ZIS type compound to form a buffer layer on the CIGS. The sulfur may be evaporated, or contained in the ZIS type material, or both. Vacuum evaporation apparatus of many types useful in the practice of the invention are known in the art. Other methods of delivery, such as sputtering, or application of a thiourea solution, may be substituted for evaporation.

  12. Method of junction formation for CIGS photovoltaic devices

    DOE Patents [OSTI]

    Delahoy, Alan E.

    2006-03-28T23:59:59.000Z

    Sulfur is used to improve the performance of CIGS devices prepared by the evaporation of a single source ZIS type compound to form a buffer layer on the CIGS. The sulfur may be evaporated, or contained in the ZIS type material, or both. Vacuum evaporation apparatus of many types useful in the practice of the invention are known in the art. Other methods of delivery, such as sputtering, or application of a thiourea solution, may be substituted for evaporation.

  13. Oxygen-reducing catalyst layer

    DOE Patents [OSTI]

    O'Brien, Dennis P. (Maplewood, MN); Schmoeckel, Alison K. (Stillwater, MN); Vernstrom, George D. (Cottage Grove, MN); Atanasoski, Radoslav (Edina, MN); Wood, Thomas E. (Stillwater, MN); Yang, Ruizhi (Halifax, CA); Easton, E. Bradley (Halifax, CA); Dahn, Jeffrey R. (Hubley, CA); O'Neill, David G. (Lake Elmo, MN)

    2011-03-22T23:59:59.000Z

    An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

  14. Apparatus and methods for impingement cooling of an undercut region adjacent a side wall of a turbine nozzle segment

    DOE Patents [OSTI]

    Burdgick, Steven Sebastian (Schenectady, NY); Itzel, Gary Michael (Simpsonville, SC)

    2001-01-01T23:59:59.000Z

    A gas turbine nozzle segment has outer and inner bands. Each band includes a side wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band and inturned flange define with the nozzle wall an undercut region. The inturned flange has a plurality of apertures for directing cooling steam to cool the side wall between adjacent nozzle segments.

  15. Phase retrapping in a pointlike $\\varphi$ Josephson junction: the Butterfly effect

    E-Print Network [OSTI]

    E. Goldobin; R. Kleiner; D. Koelle; R. G. Mints

    2013-07-30T23:59:59.000Z

    We consider a $\\varphi$ Josephson junction, which has a bistable zero-voltage state with the stationary phases $\\psi=\\pm\\varphi$. In the non-zero voltage state the phase "moves" viscously along a tilted periodic double-well potential. When the tilting is reduced quasistatically, the phase is retrapped in one of the potential wells. We study the viscous phase dynamics to determine in which well ($-\\varphi$ or $+\\varphi$) the phase is retrapped for a given damping, when the junction returns from the finite-voltage state back to zero-voltage state. In the limit of low damping the $\\varphi$ Josephson junction exhibits a butterfly effect --- extreme sensitivity of the destination well on damping. This leads to an impossibility to predict the destination well.

  16. Bunching of fluxons in a long Josephson junction with surface losses

    SciTech Connect (OSTI)

    Malomed, B.A. (Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois (United States))

    1993-01-01T23:59:59.000Z

    It is known that the sine-Gordon model of a long Josephson junction with a surface-loss term predicts a spatially oscillating trailing tail of a strongly contracted fluxon. In the present work, it is demonstrated that this should give rise to bunched (bound) states of fluxons, although the onset of the bunching drastically differs from the standard situation recently investigated in terms of the perturbed nonlinear Schroedinger model. Influence of the bunching on the [ital I]-[ital V] characteristic of an annular junction with a finite number of trapped fluxons is analyzed qualitatively. It is demonstrated that the bunching may set in with a small hysteresis, and it increases voltage at a given current. The latter effect has been observed in most recent experiments with the annular junction.

  17. Alternating dynamic state in intrinsic Josephson-junction stacks self-generated by internal resonance.

    SciTech Connect (OSTI)

    Koshelev, A. E.; Materials Science Division

    2008-01-01T23:59:59.000Z

    Intrinsic Josephson-junction stacks realized in high-temperature superconductors provide a very attractive base for developing coherent sources of electromagnetic radiation in the terahertz frequency range. A promising way to synchronize phase oscillations in all the junctions is to excite an internal cavity resonance. We demonstrate that this resonance promotes the formation of an alternating coherent state, in which the system spontaneously splits into two subsystems with different phase-oscillation patterns. There is a static phase shift between the oscillations in the two subsystems, which changes from 0 to 2 in a narrow region near the stack center. The oscillating electric and magnetic fields are almost homogeneous in all the junctions. The formation of this state promotes efficient pumping of the energy into the cavity resonance leading to strong resonance features in the current-voltage dependence.

  18. Nonequilibrium transport through quantum-wire junctions and boundary defects for free massless bosonic fields

    E-Print Network [OSTI]

    Gaw?dzki, Krzysztof

    2015-01-01T23:59:59.000Z

    We consider a model of quantum-wire junctions where the latter are described by conformal-invariant boundary conditions of the simplest type in the multicomponent compactified massless scalar free field theory representing the bosonized Luttinger liquids in the bulk of wires. The boundary conditions result in the scattering of charges across the junction with nontrivial reflection and transmission amplitudes. The equilibrium state of such a system, corresponding to inverse temperature $\\beta$ and electric potential $V$, is explicitly constructed both for finite and for semi-infinite wires. In the latter case, a stationary nonequilibrium state describing the wires kept at different temperatures and potentials may be also constructed. The main result of the present paper is the calculation of the full counting statistics (FCS) of the charge and energy transfers through the junction in a nonequilibrium situation. Explicit expressions are worked out for the generating function of FCS and its large-deviations asym...

  19. Delocalised oxygen as the origin of two-level defects in Josephson junctions

    E-Print Network [OSTI]

    Timothy C. DuBois; Manolo C. Per; Salvy P. Russo; Jared H. Cole

    2012-06-12T23:59:59.000Z

    One of the key problems facing superconducting qubits and other Josephson junction devices is the decohering effects of bi-stable material defects. Although a variety of phenomenological models exist, the true microscopic origin of these defects remains elusive. For the first time we show that these defects may arise from delocalisation of the atomic position of the oxygen in the oxide forming the Josephson junction barrier. Using a microscopic model, we compute experimentally observable parameters for phase qubits. Such defects are charge neutral but have non-zero response to both applied electric field and strain. This may explain the observed long coherence time of two-level defects in the presence of charge noise, while still coupling to the junction electric field and substrate phonons.

  20. Calmodulin Kinase Pathway Mediates the K ?-Induced Increase in Gap Junctional Communication between Mouse Spinal Cord

    E-Print Network [OSTI]

    Mara H. De Pina-benabou; Miduturu Srinivas; David C. Spray; Eliana Scemes

    Astrocytes are coupled to one another by gap junction channels that allow the diffusion of ions and small molecules throughout the interconnected syncytium. In astrocytes, gap junctions are believed to participate in spatial buffering removing the focal excess of potassium resultant from intense neuronal activity by current loops through the syncytium and are also implicated in the propagation of astrocytic calcium waves, a form of extraneuronal signaling. Gap junctions can be modulated by several factors, including elevation of extracellular potassium concentration. Because K ? elevation is a component of spinal cord injury, we evaluated the extent to which cultured spinal cord astrocytes is affected by K ? levels and obtained evidence suggesting that a Ca 2 ? –calmodulin (CaM) protein kinase is involved in the K ?-induced increased coupling. Exposure of astrocytes to high K ? solutions induced a

  1. Distribution of Pd, Ag & U in the SiC Layer of an Irradiated TRISO Fuel Particle

    SciTech Connect (OSTI)

    Thomas M. Lillo; Isabella J. van Rooyen

    2014-08-01T23:59:59.000Z

    The distribution of silver, uranium and palladium in the silicon carbide (SiC) layer of an irradiated TRISO fuel particle was studied using samples extracted from the SiC layer using focused ion beam (FIB) techniques. Transmission electron microscopy in conjunction with energy dispersive x-ray spectroscopy was used to identify the presence of the specific elements of interest at grain boundaries, triple junctions and precipitates in the interior of SiC grains. Details on sample fabrication, errors associated with measurements of elemental migration distances and the distances migrated by silver, palladium and uranium in the SiC layer of an irradiated TRISO particle from the AGR-1 program are reported.

  2. Diagnostics of the Coronal Hole and the adjacent Quiet Sun by The Hinode/EUV Imaging Spectrometer (EIS)

    E-Print Network [OSTI]

    Kayshap, P; Srivastava, A K

    2014-01-01T23:59:59.000Z

    A comparison between a Coronal Hole (CH) and the adjacent Quiet-Sun (QS) has been performed using spectroscopic diagnostics of Hinode/ the EUV Imaging Spectrometer (EIS). Coronal funnels play an important role in the formation and propagation of the nascent fast solar wind. Applying Gaussian fitting procedures to the observed line profiles, Doppler velocity, intensity, line width (FWHM) and electron density have been estimated over CH and adjacent QS region of a North Polar Coronal Hole (NPCH). The aim of this study is to identify the coronal funnels based on spectral signatures. Excess width regions (excess FWHM above a threshold level) have been identified in QS and CH. The plasma flow inversion (average red-shifts changing to blue-shifts at a specific height) in CH and excess width regions of QS take place at ~ 5.01$\\times$10$^{5}$ K. Furthermore, high density concentration in excess width regions of QS provides an indication that these regions are the footprints of coronal funnels. We have also found that...

  3. Strongly-coupled Josephson junction array for simulation of frustrated one-dimensional spin models

    E-Print Network [OSTI]

    Liang-Hui Du; Xingxiang Zhou; Yong-Jian Han; Guang-Can Guo; Zheng-Wei Zhou

    2012-12-20T23:59:59.000Z

    We study the capacitance-coupled Josephson junction array beyond the small-coupling limit. We find that, when the scale of the system is large, its Hamiltonian can be obtained without the small-coupling approximation and the system can be used to simulate strongly frustrated one-dimensional Ising spin problems. To engineer the system Hamiltonian for an ideal theoretical model, we apply a dynamical decoupling technique to eliminate undesirable couplings in the system. Using a 6-site junction array as an example, we numerically evaluate the system to show that it exhibits important characteristics of the frustrated spin model.

  4. Manipulating the magnetic state of a carbon nanotube Josephson junction using the superconducting phase

    E-Print Network [OSTI]

    R. Delagrange; D. J. Luitz; R. Weil; A. Kasumov; V. Meden; H. Bouchiat; R. Deblock

    2015-01-14T23:59:59.000Z

    We study the supercurrent of a carbon nanotube quantum dot Josephson junction in a parameter regime in which the Kondo energy and the superconducting gap are of comparable size. For gate voltages in the vicinity of a Kondo ridge the superconducting phase difference can then be used to tune the magnetic state from a singlet to a doublet. Accordingly our measured current phase relation crosses over from 0 to $\\pi$-junction behavior, exhibiting strong anharmonicities. The experimental results are in excellent agreement with our numerically exact finite temperature quantum Monte Carlo simulations and provide insights on the phase-controlled level-crossing transition at zero temperature.

  5. Hetero-junctions of Boron Nitride and Carbon Nanotubes: Synthesis and Characterization

    SciTech Connect (OSTI)

    Yap, Yoke Khin

    2013-03-14T23:59:59.000Z

    Hetero-junctions of boron nitride nanotubes (BNNTs) and carbon nanotubes (CNTs) are expected to have appealing new properties that are not available from pure BNNTs and CNTs. Theoretical studies indicate that BNNT/CNT junctions could be multifunctional and applicable as memory, spintronic, electronic, and photonics devices with tunable band structures. This will lead to energy and material efficient multifunctional devices that will be beneficial to the society. However, experimental realization of BNNT/CNT junctions was hindered by the absent of a common growth technique for BNNTs and CNTs. In fact, the synthesis of BNNTs was very challenging and may involve high temperatures (up to 3000 degree Celsius by laser ablation) and explosive chemicals. During the award period, we have successfully developed a simple chemical vapor deposition (CVD) technique to grow BNNTs at 1100-1200 degree Celsius without using dangerous chemicals. A series of common catalyst have then been identified for the synthesis of BNNTs and CNTs. Both of these breakthroughs have led to our preliminary success in growing two types of BNNT/CNT junctions and two additional new nanostructures: 1) branching BNNT/CNT junctions and 2) co-axial BNNT/CNT junctions, 3) quantum dots functionalized BNNTs (QDs-BNNTs), 4) BNNT/graphene junctions. We have started to understand their structural, compositional, and electronic properties. Latest results indicate that the branching BNNT/CNT junctions and QDs-BNNTs are functional as room-temperature tunneling devices. We have submitted the application of a renewal grant to continue the study of these new energy efficient materials. Finally, this project has also strengthened our collaborations with multiple Department of Energy�s Nanoscale Science Research Centers (NSRCs), including the Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National Laboratory, and the Center for Integrated Nanotechnologies (CINTs) at Sandia National Laboratories and Los Alamos National Laboratory. Results obtained during the current funding period have led to the publication of twelve peer reviewed articles, three review papers, two book and one encyclopedia chapters, and thirty eight conference/seminar presentation. One US provisional patent and one international patent have also been filed.

  6. Using ion irradiation to make high-T{sub c} Josephson junctions

    SciTech Connect (OSTI)

    Bergeal, N.; Lesueur, J.; Sirena, M.; Faini, G.; Aprili, M.; Contour, J. P.; Leridon, B. [Laboratoire de Physique Quantique, ESPCI-UPR5 CNRS, 10 Rue Vauquelin, 75231 Paris (France); Laboratoire de Photonique et Nanostructures, LPN-CNRS, Route de Nozay, 91460 Marcoussis (France); Laboratoire de Physique Quantique, ESPCI-UPR5 CNRS, 10 Rue Vauquelin, 75231 Paris (France); Unite Mixte de Physique, CNRS/THALES, Route Departementale 128, 91767 Palaiseau (France); Laboratoire de Physique Quantique, ESPCI-UPR5 CNRS, 10 Rue Vauquelin, 75231 Paris (France)

    2007-10-15T23:59:59.000Z

    In this article we describe the effect of ion irradiation on high-T{sub c} superconductor thin film and its interest for the fabrication of Josephson junctions. In particular, we show that these alternative techniques allow to go beyond most of the limitations encountered in standard junction fabrication methods, both in the case of fundamental and technological purposes. Two different geometries are presented: a planar one using a single high-T{sub c} film and a mesa one defined in a trilayer structure.

  7. Single-junction solar cells with the optimum band gap for terrestrial concentrator applications

    DOE Patents [OSTI]

    Wanlass, M.W.

    1994-12-27T23:59:59.000Z

    A single-junction solar cell is described having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of ''pinning'' the optimum band gap for a wide range of operating conditions at a value of 1.14[+-]0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap. 7 figures.

  8. Detection of coherent superpositions of phase states by full counting statistics in a Bose Josephson junction

    SciTech Connect (OSTI)

    Ferrini, G.; Minguzzi, A.; Hekking, F. W. J. [Laboratoire de Physique et Modelisation des Milieux Condenses, Universite Joseph Fourier-CNRS, BP 166, 38042 Grenoble (France)

    2009-10-15T23:59:59.000Z

    We study a Bose Josephson junction realized with a double-well potential. We propose a strategy to observe the coherent superpositions of phase states occurring during the time evolution after a sudden rise of the barrier separating the two wells. We show that their phase content can be obtained by the full counting statistics of the spin-boson operators characterizing the junction, which could be mapped out by repeated measurements of the population imbalance after rotation of the state. This measurement can distinguish between coherent superpositions and incoherent mixtures, and can be used for a two-dimensional tomographic reconstruction of the phase content of the state.

  9. Direct Observation of Tunneling and Nonlinear Self-Trapping in a Single Bosonic Josephson Junction

    SciTech Connect (OSTI)

    Albiez, Michael; Gati, Rudolf; Foelling, Jonas; Hunsmann, Stefan; Oberthaler, Markus K. [Kirchhoff-Institut fuer Physik, Universitaet Heidelberg, Im Neuenheimer Feld 227, D-69120 Heidelberg (Germany); Cristiani, Matteo [CNR-INFM, Dipartimento di Fisica E. Fermi, Universita di Pisa, Largo B. Pontecorvo 3, I-56127 Pisa (Italy)

    2005-07-01T23:59:59.000Z

    We report on the first realization of a single bosonic Josephson junction, implemented by two weakly linked Bose-Einstein condensates in a double-well potential. In order to fully investigate the nonlinear tunneling dynamics we measure the density distribution in situ and deduce the evolution of the relative phase between the two condensates from interference fringes. Our results verify the predicted nonlinear generalization of tunneling oscillations in superconducting and superfluid Josephson junctions. Additionally, we confirm a novel nonlinear effect known as macroscopic quantum self-trapping, which leads to the inhibition of large amplitude tunneling oscillations.

  10. Defect motion and lattice pinning barriers in Josephson-junction ladders

    SciTech Connect (OSTI)

    Kang, H.; Lim, Jong Soo [Department of Physics and Center for Theoretical Physics, Seoul National University, Seoul 151-747 (Korea, Republic of); Fortin, J.-Y. [Laboratoire de Physique Theorique, Universite Louis Pasteur, 67084 Strasbourg (France); Choi, J. [Department of Physics, Keimyung University, Daegu 704-701 (Korea, Republic of); Choi, M. Y. [Department of Physics and Center for Theoretical Physics, Seoul National University, Seoul 151-747 (Korea, Republic of); Korea Institute for Advanced Study, Seoul 130-722 (Korea, Republic of)

    2006-01-01T23:59:59.000Z

    We study the motion of domain wall defects in a fully frustrated Josephson-junction ladder system, driven by small applied currents. For small system sizes, the energy barrier E{sub B} to the defect motion is computed analytically via symmetry and topological considerations. More generally, we perform numerical simulations directly on the equations of motion, based on the resistively-shunted junction model, to study the dynamics of defects, varying the system size. Coherent motion of domain walls is observed for large system sizes. In the thermodynamical limit, we find E{sub B}=0.1827 in units of the Josephson coupling energy.

  11. Atomic delocalisation as a microscopic origin of two-level defects in Josephson junctions

    E-Print Network [OSTI]

    Timothy C. DuBois; Salvy P. Russo; Jared H. Cole

    2014-08-25T23:59:59.000Z

    Identifying the microscopic origins of decoherence sources prevalent in Josephson junction based circuits is central to their use as functional quantum devices. Focussing on so called "strongly coupled" two-level defects, we construct a theoretical model using the atomic position of the oxygen which is spatially delocalised in the oxide forming the Josephson junction barrier. Using this model, we investigate which atomic configurations give rise to two-level behaviour of the type seen in experiments. We compute experimentally observable parameters for phase qubits and examine defect response under the effects of applied electric field and strain.

  12. Microwave-induced ''Devil's Staircase'' structure and ''Chaotic'' behavior in current-fed Josephson junctions

    SciTech Connect (OSTI)

    Ben-Jacob, E.; Braiman, Y.; Shainsky, R.; Imry, Y.

    1981-05-15T23:59:59.000Z

    We have obtained the various types of I-V characteristics measured experimentally and in analog simulations, by merely changing the junction and the microwave parameters within the same resistively shunted junction model with purely sinusoidal current-phase relation. It was found that the subharmonic steps do exist in the limit b/sub c/..-->..0, though they can have finite rounding without thermal noise. The statistical properties of the ''chaotic'' solutions wer e discussed and their effective temperature was defined and calculated.

  13. MODELING OF TRIPLE JUNCTION A-SI SOLAR CELLS USING ASA: ANALYSIS OF DEVICE PERFORMANCE UNDER VARIOUS FAILURE SCENARIOS

    E-Print Network [OSTI]

    Deng, Xunming

    have experienced a significant increase in the recent years. Solar panels with triple- junction found. To assist the optimization of solar cell fabrication and cost-effective industrial photovoltaicMODELING OF TRIPLE JUNCTION A-SI SOLAR CELLS USING ASA: ANALYSIS OF DEVICE PERFORMANCE UNDER

  14. Crossover from diffusive to tunneling regime in NbN/DyN/NbN ferromagnetic semiconductor tunnel junctions

    E-Print Network [OSTI]

    Muduli, P. K.; Pal, Avradeep; Blamire, Mark G.

    2014-03-19T23:59:59.000Z

    , ?(T ) = ?(0) tanh(2.2 ? (TC ? T )/T ), with 2?(0) = 3.07 meV and TC = 10.74 K. Junctions with ?1 nm DyN showed Josephson junction like behavior with a small critical current IC ?12 µA as shown in Fig. 4(b). The magnetic field dependence of IC is shown...

  15. PHYSICAL REVIEW B 90, 075401 (2014) Subgap structure in the conductance of a three-terminal Josephson junction

    E-Print Network [OSTI]

    Boyer, Edmond

    -terminal Josephson junction A. H. Pfeffer,1,2 J. E. Duvauchelle,1,2 H. Courtois,3,4 R. M´elin,3,4 D. Feinberg,3)-superconductor (S) Josephson junctions are investigated. In a geometry where a T-shape normal metal is connected

  16. Phase Diffusion in Graphene-Based Josephson Junctions I. V. Borzenets, U. C. Coskun, S. J. Jones, and G. Finkelstein

    E-Print Network [OSTI]

    Finkelstein, Gleb

    Phase Diffusion in Graphene-Based Josephson Junctions I. V. Borzenets, U. C. Coskun, S. J. Jones July 2011; published 21 September 2011) We report on graphene-based Josephson junctions with contacts. We attribute this resistance to the phase diffusion mechanism, which has not been yet identified

  17. HIGH-EFFICIENCY BACK-JUNCTION SILICON SOLAR CELL WITH AN IN-LINE EVAPORATED ALUMINUM FRONT GRID

    E-Print Network [OSTI]

    HIGH-EFFICIENCY BACK-JUNCTION SILICON SOLAR CELL WITH AN IN-LINE EVAPORATED ALUMINUM FRONT GRID M-diffused back-junction emitter. The aluminum front side grid is evaporated in an industrial-type in-thick silicon shadow masks for the in-line evaporation of the aluminum front grid. The masks are fabricated

  18. Effect of Front-Side Silver Metallization on Underlying n+-p Junction in Multicrystalline Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Jiang, C. S.; Li, Z. G.; Moutinho, H. R.; Liang, L.; Ionkin, A.; Al-Jassim, M. M.

    2012-06-01T23:59:59.000Z

    We report on the effect of front-side Ag metallization on the underlying n+-p junction of multicrystalline Si solar cells. The junction quality beneath the contacts was investigated by characterizing the uniformities of the electrostatic potential and doping concentration across the junction, using scanning Kelvin probe force microscopy and scanning capacitance microscopy. We investigated cells with a commercial Ag paste (DuPont PV159) and fired at furnace setting temperatures of 800 degrees, 840 degrees, and 930 degrees C, which results in actual cell temperatures ~100 degrees C lower than the setting temperature and the three cells being under-, optimal-, and over-fired. We found that the uniformity of the junction beneath the Ag contact was significantly degraded by the over-firing, whereas the junction retained good uniformity with the optimal- and under-fire temperatures. Further, Ag crystallites with widely distributed sizes from <100 nm to several ?m were found at the Ag/Si interface of the over-fired cell. Large crystallites were imaged as protrusions into Si deeper than the junction depth. However, the junction was not broken down; instead, it was reformed on the entire front of the crystallite/Si interface. We propose a mechanism of the junction-quality degradation, based on emitter Si melting at the temperature around the Ag-Si eutectic point during firing, and subsequent recrystallization with incorporation of impurities in the Ag paste and with formation of crystallographic defects during quenching.

  19. Chapter 8: PhotodetectorsChapter 8: Photodetectors i i l f j i h di dPrinciple of pn junction photodiodes

    E-Print Network [OSTI]

    Wang, Jianfang

    photodiodes RAMO's theorem and external photocurrentp Photodiode materials Quantum efficiency and responsivity pin photodiodespin photodiodes Avalanche photodiodes Heterojunction photodiodes Photoconductive;Principle of the pn Junction PhotodiodesPrinciple of the pn Junction Photodiodes Photodetectors/photodiodes

  20. he transfer of a quantum state between distant locations can be realized using condensed matter systems such as spin chains and Josephson junction arrays. The

    E-Print Network [OSTI]

    Abbondandolo, Alberto

    systems such as spin chains and Josephson junction arrays. The feasibility of such proposals may open, leads to clear signatures of crossed boxes are the Josephson junctions the modified properties

  1. Nanoengineering Catalyst Supports via Layer-by Layer Surface Functionalization

    SciTech Connect (OSTI)

    Yan, Wenfu [ORNL; Mahurin, Shannon Mark [ORNL; Overbury, Steven {Steve} H [ORNL; Dai, Sheng [ORNL

    2006-01-01T23:59:59.000Z

    Recent progress in the layer-by-layer surface modification of oxides for the preparation of highly active and stable gold nanocatalysts is briefly reviewed. Through a layer-by-layer surface modification approach, the surfaces of various catalyst supports including both porous and nonporous silica materials and TiO{sub 2} nanoparticles were modified with monolayers or multilayers of distinct metal oxide ultra-thin films. The surface-modified materials were used as supports for Au nanoparticles, resulting in highly active nanocatalysts for low-temperature CO oxidation. Good stability against sintering under high-temperature treatment was achieved for a number of the Au catalysts through surface modification of the support material. The surface modification of supports can be a viable route to control both the composition and structure of support and nanoparticle interfaces, thereby tailoring the stability and activity of the supported catalyst systems.

  2. D0 layer 0 innermost layer of silicon microstrip tracker

    SciTech Connect (OSTI)

    Hanagaki, K.; /Fermilab

    2006-01-01T23:59:59.000Z

    A new inner layer silicon strip detector has been built and will be installed in the existing silicon microstrip tracker in D0. They report on the motivation, design, and performance of this new detector.

  3. Layer-By-Layer Assembled Hybrid Film of Carbon Nanotubes/Iron...

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

    By-Layer Assembled Hybrid Film of Carbon NanotubesIron Oxide Nanocrystals for Reagentless Electrochemical Detection of Layer-By-Layer Assembled Hybrid Film of Carbon Nanotubes...

  4. Optimization of Spin-Triplet Supercurrent in Ferromagnetic Josephson Junctions Carolin Klose, Trupti S. Khaire, Yixing Wang, W. P. Pratt, Jr., and Norman O. Birge*

    E-Print Network [OSTI]

    Birge, Norman

    Optimization of Spin-Triplet Supercurrent in Ferromagnetic Josephson Junctions Carolin Klose-range spin-triplet supercurrents in Josephson junctions containing ferromag- netic (F) materials, which for spin-triplet super- current in S/F/S Josephson junctions containing only conventional spin

  5. Microwave bifurcation of a Josephson junction: Embedding-circuit requirements V. E. Manucharyan, E. Boaknin, M. Metcalfe, R. Vijay, I. Siddiqi,* and M. Devoret

    E-Print Network [OSTI]

    Devoret, Michel H.

    Microwave bifurcation of a Josephson junction: Embedding-circuit requirements V. E. Manucharyan, E with the nonlinear dynamics of a Josephson junction embedded in an arbitrary microwave circuit. We find sufficient recently proposed3,4 to use the dynamical bifurcation of a rf-biased Josephson junction JJ as a basis

  6. JOURNAL DE PHYSIQUE Colloque C6, supplgment au no 8, Tome 39, aotit 1978,page C6-575 NOISE DOWN-CONVERSION IN A PUMPED JOSEPHSON JUNCTION

    E-Print Network [OSTI]

    Boyer, Edmond

    -CONVERSION IN A PUMPED JOSEPHSON JUNCTION NASA Goddard Institute for Space Studies, Goddard Space Flight Center, New York Josephson junction i s stu- died numerically. Calculation shows t h a t the excess low-frequency noise i n simulator has been used to compute the low- frequency noise i n a pumped Josephson junction / 4 / . Although

  7. arXiv:1008.2085v3[astro-ph.CO]23Nov2011 Axion physics in a Josephson junction environment

    E-Print Network [OSTI]

    Beck, Christian

    arXiv:1008.2085v3[astro-ph.CO]23Nov2011 Axion physics in a Josephson junction environment Christian experiments based on Josephson junctions, SQUIDS, and coupled Josephson qubits have a cosmological inter- actions in a resonant Josephson junction environment can be tested, similar in nature to recent

  8. arXiv:1110.5871v1[astro-ph.IM]26Oct2011 Testing axion physics in a Josephson junction environment

    E-Print Network [OSTI]

    Beck, Christian

    arXiv:1110.5871v1[astro-ph.IM]26Oct2011 Testing axion physics in a Josephson junction environmentNS, UK We suggest that experiments based on Josephson junctions, SQUIDS, and coupled Josephson qubits in which axionic interaction strengths in a Josephson junction environment can be tested, similar in nature

  9. This approximation simplifies the analysis of fluxon oscillations by avoiding the compli-cated interplay with cavity resonances. It is valid for very long junctions ( ) used in

    E-Print Network [OSTI]

    Wallraff, Andreas

    magnetically coupled long Josephson junctions is reported. Time dependent synchronized voltage response. Simulations show that Josephson junctions operating in the in­phase flux­flow mode may generate rf radiation power by a factor of more than four larger than that of a single Josephson junction. The radiation

  10. Ann. Phys. (Leipzig) 16, No. 1011, 736750 (2007) / DOI 10.1002/andp.200710263 Josephson junctions as detectors for non-Gaussian noise

    E-Print Network [OSTI]

    Birge, Norman

    Ann. Phys. (Leipzig) 16, No. 10­11, 736­750 (2007) / DOI 10.1002/andp.200710263 Josephson junctions 2007 Key words Josephson junction, noise, counting statistics. PACS 72.70.+m, 74.40.+k, 74.50.+r of the electrical current can be detected with a Josephson junction placed on-chip with the noise source. We present

  11. One-dimensional Mott localization of quantum vortices in Josephson-junction arrays A. van Oudenaarden, B. van Leeuwen, M. P. M. Robbens, and J. E. Mooij

    E-Print Network [OSTI]

    van Oudenaarden, Alexander

    One-dimensional Mott localization of quantum vortices in Josephson-junction arrays A. van long and narrow arrays of small Josephson junctions is studied experimentally. We investigate for electrons and a superfluid phase for bosons. One- dimensional Josephson-junction arrays are very suitable

  12. Nano-superconducting quantum interference devices with suspended junctions

    SciTech Connect (OSTI)

    Hazra, D.; Hasselbach, K. [Institut Néel, CNRS and Université Joseph Fourier, 25 Avenue des Martyrs, Grenoble (France); Kirtley, J. R. [Center for Probing the Nanoscale, Stanford University, Palo Alto, California 94305-4045 (United States)

    2014-04-14T23:59:59.000Z

    Nano-Superconducting Quantum Interference Devices (nano-SQUIDs) are usually fabricated from a single layer of either Nb or Al. We describe here a simple method for fabricating suspended nano-bridges in Nb/Al thin-film bilayers. We use these suspended bridges, which act as Josephson weak links, to fabricate nano-SQUIDs which show critical current oscillations at temperatures up to 1.5?K and magnetic flux densities up to over 20?mT. These nano-SQUIDs exhibit flux modulation depths intermediate between all-Al and all-Nb devices, with some of the desirable characteristics of both. The suspended geometry is attractive for magnetic single nanoparticle measurements.

  13. Thermal conductance of the junction between single-walled carbon nanotubes

    E-Print Network [OSTI]

    McGaughey, Alan

    conductances of the carbon nanotube (CNT) junctions that would be found in a CNT aerogel are predicted using of carbon nanotubes (CNTs) (e.g., aligned films, mats, and aerogels) are candidates for use in electronic issue in all of these applications. Our focus here is related to single-walled CNT aerogels, which

  14. Improved One-dimensional Analysis of CMOS Photodiode Including Epitaxial-Substrate Junction

    E-Print Network [OSTI]

    Hornsey, Richard

    1 Improved One-dimensional Analysis of CMOS Photodiode Including Epitaxial-Substrate Junction J. S-dimensional analysis of CMOS photodiode has been derived in which the effect of the substrate, which forms a high-empirical expression exhibits a good agreement with the measured spectral response of n+ pepi photodiodes fabricated

  15. ELECTRONICS' 2008 24 26 September, Sozopol, BULGARIA RESPONSE TIME OF SHALLOW JUNCTION SILICON PHOTODIODES

    E-Print Network [OSTI]

    Technische Universiteit Delft

    PHOTODIODES Lei Shi1 , Sha Xia1 , Francesco Sarubbi1 , Rik Naulaerts2 , Stoyan Nihtianov1,2 , Lis Nanver1 1, shape and location of the illuminated part of a shallow-junction photodiode, and its series resistance for which the photo-generated charge will be removed from the photodiode) with the illuminated spot size

  16. Site observational work plan for the UMTRA Project Site at Grand Junction, Colorado

    SciTech Connect (OSTI)

    NONE

    1996-03-01T23:59:59.000Z

    The U.S. Department of Energy (DOE) has prepared this initial site observational work plan (SOWP) for the Uranium Mill Tailings Remedial Action (UMTRA) Project site in Grand Junction, Colorado. This SOWP is one of the first UMTRA Ground Water Project documents developed to select a compliance strategy that meets the UMTRA ground water standards (40 CFR Part 192, as amended by 60 FR 2854) for the Grand Junction site. This SOWP applies information about the Grand Junction site to the compliance strategy selection framework developed in the UMTRA Ground Water Project draft programmatic environmental impact statement (PEIS). This risk-based, decision-making framework identifies the decision logic for selecting compliance strategies that could be used to meet the ground water standards. The DOE goal is to use the observational method to implement a cost-effective site strategy that complies with the ground water standards and protects human health and the environment. Based on an evaluation of the site characterization and risk assessment data available for the preparation of this SOWP, DOE proposes that the most likely compliance strategy for the Grand Junction site is no remediation based on the application of supplemental standards. This proposed strategy is based on a conceptual site model that indicates site-related contamination is confined to a limited-use aquifer as defined in the ground water standards.

  17. Electronic Heating at High Bias in Atomic-Scale Au Break Junctions Ruoyu Chen,1

    E-Print Network [OSTI]

    , U.S.A. Heating in nanoscale systems driven out of equilibrium is of fundamental importance, has O-10 Electronic Heating at High Bias in Atomic-Scale Au Break Junctions Ruoyu Chen,1, Texas, U.S.A. 2 Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005

  18. A solvable model for scattering on a junction and a modified analytic perturbation procedure

    E-Print Network [OSTI]

    B. Pavlov

    2009-02-24T23:59:59.000Z

    We consider a one-body spin-less electron spectral problem for a resonance scattering system constructed of a quantum well weakly connected to a noncompact exterior reservoir, where the electron is free. The simplest kind of the resonance scattering system is a quantum network, with the reservoir composed of few disjoint cylindrical quantum wires, and the Schr\\"{o}dinger equation on the network, with the real bounded potential on the wells and constant potential on the wires. We propose a Dirichlet-to-Neumann - based analysis to reveal the resonance nature of conductance across the star-shaped element of the network (a junction), derive an approximate formula for the scattering matrix of the junction, construct a fitted zero-range solvable model of the junction and interpret a phenomenological parameter arising in Datta-Das Sarma boundary condition, see {\\cite{DattaAPL}, for T-junctions. We also propose using of the fitted zero-range solvable model as the first step in a modified analytic perturbation procedure of calculation of the corresponding scattering matrix.

  19. System vendor Contents Type Location Removal of Misc Cable, Conduit and Junction Boxes

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    System vendor Contents Type Location Removal of Misc Cable, Conduit and Junction Boxes in the NCSX;System vendor Contents Type Location Installation for NCSX Power Cables Procedure Procedure Files IP Procedure Procedure Files IP-NCSX-2972 #12;System vendor Contents Type Location Coils NCSX Coil System DC

  20. N-PERT BACK JUNCTION SOLAR CELLS: AN OPTION FOR THE NEXT INDUSTRIAL TECHNOLOGY GENERATION?

    E-Print Network [OSTI]

    are introducing a new solar cell design: the Passivated Emitter and Rear Cell (PERC), which features a full-PERT (Passivated Emitter, Rear Totally Diffused) solar cells with a processing sequence based on an industrialN-PERT BACK JUNCTION SOLAR CELLS: AN OPTION FOR THE NEXT INDUSTRIAL TECHNOLOGY GENERATION? Bianca