National Library of Energy BETA

Sample records for limiting fcl superconducting

  1. Superconducting FCL using a combined inducted magnetic field trigger and shunt coil

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D. (Rexford, NY)

    2007-10-16

    A single trigger/shunt coil is utilized for combined induced magnetic field triggering and shunt impedance. The single coil connected in parallel with the high temperature superconducting element, is designed to generate a circulating current in the parallel circuit during normal operation to aid triggering the high temperature superconducting element to quench in the event of a fault. The circulating current is generated by an induced voltage in the coil, when the system current flows through the high temperature superconducting element.

  2. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, J.R.

    1997-02-04

    A fault current limiter for an electrical circuit is disclosed. The fault current limiter includes a high temperature superconductor in the electrical circuit. The high temperature superconductor is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter. 15 figs.

  3. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1997-01-01

    A fault current limiter (10) for an electrical circuit (14). The fault current limiter (10) includes a high temperature superconductor (12) in the electrical circuit (14). The high temperature superconductor (12) is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter (10).

  4. Self-triggering superconducting fault current limiter

    DOE Patents [OSTI]

    Yuan, Xing (Albany, NY); Tekletsadik, Kasegn (Rexford, NY)

    2008-10-21

    A modular and scaleable Matrix Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. The matrix fault current limiter comprises a fault current limiter module that includes a superconductor which is electrically coupled in parallel with a trigger coil, wherein the trigger coil is magnetically coupled to the superconductor. The current surge doing a fault within the electrical power network will cause the superconductor to transition to its resistive state and also generate a uniform magnetic field in the trigger coil and simultaneously limit the voltage developed across the superconductor. This results in fast and uniform quenching of the superconductors, significantly reduces the burnout risk associated with non-uniformity often existing within the volume of superconductor materials. The fault current limiter modules may be electrically coupled together to form various "n" (rows).times."m" (columns) matrix configurations.

  5. Self field triggered superconducting fault current limiter

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D. (Rexford, NY)

    2008-02-19

    A superconducting fault current limiter array with a plurality of superconductor elements arranged in a meanding array having an even number of supconductors parallel to each other and arranged in a plane that is parallel to an odd number of the plurality of superconductors, where the odd number of supconductors are parallel to each other and arranged in a plane that is parallel to the even number of the plurality of superconductors, when viewed from a top view. The even number of superconductors are coupled at the upper end to the upper end of the odd number of superconductors. A plurality of lower shunt coils each coupled to the lower end of each of the even number of superconductors and a plurality of upper shunt coils each coupled to the upper end of each of the odd number of superconductors so as to generate a generally orthoganal uniform magnetic field during quenching using only the magenetic field generated by the superconductors.

  6. Superconducting fault current-limiter with variable shunt impedance

    DOE Patents [OSTI]

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19

    A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

  7. Superconducting quantum interference device as a near-quantum-limited amplifier at 0.5 GHz

    E-Print Network [OSTI]

    Le Roy, Robert J.

    Superconducting quantum interference device as a near-quantum-limited amplifier at 0.5 GHz Michael 94720 Received 10 October 2000; accepted for publication 14 December 2000 A dc superconducting quantum, for example, superconducting transition-edge sensors for infrared, optical, and ultraviolet wavelengths,2

  8. Investigation of Microscopic Materials Limitations of Superconducting RF Cavities

    SciTech Connect (OSTI)

    Anlage, Steven

    2014-07-23

    The high-field performance of SRF cavities is often limited by breakdown events below the intrinsic limiting surface fields of Nb, and there is abundant evidence that these breakdown events are localized in space inside the cavity. Also, there is a lack of detailed understanding of the causal links between surface treatments and ultimate RF performance at low temperatures. An understanding of these links would provide a clear roadmap for improvement of SRF cavity performance, and establish a cause-and-effect ‘RF materials science’ of Nb. We propose two specific microscopic approaches to addressing these issues. First is a spatially-resolved local microwave-microscope probe that operates at SRF frequencies and temperatures to discover the microscopic origins of breakdown, and produce quantitative measurements of RF critical fields of coatings and films. Second, RF Laser Scanning Microscopy (LSM) has allowed visualization of RF current flow and sources of nonlinear RF response in superconducting devices with micro-meter spatial resolution. The LSM will be used in conjunction with surface preparation and characterization techniques to create definitive links between physical and chemical processing steps and ultimate cryogenic microwave performance. We propose to develop RF laser scanning microscopy of small-sample Nb pieces to establish surface-processing / RF performance relations through measurement of RF current distributions on micron-length scales and low temperatures.

  9. Switching Currents Limited by Single Phase Slips in One-Dimensional Superconducting Al Nanowires

    E-Print Network [OSTI]

    Finkelstein, Gleb

    Switching Currents Limited by Single Phase Slips in One-Dimensional Superconducting Al Nanowires received 10 January 2011; published 21 September 2011) An aluminum nanowire switches from superconducting to normal as the current is increased in an upsweep. The switching current (Is) averaged over upsweeps

  10. Fault Current Limiters (FCL) Fact Sheet | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRD Report to Congress MoreHyd rog enOffice|DOEofPrimusonFanPlugging

  11. Superconducting matrix fault current limiter with current-driven trigger mechanism

    DOE Patents [OSTI]

    Yuan; Xing (Albany, NY)

    2008-04-15

    A modular and scalable Matrix-type Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. An inductor is connected in series with the trigger superconductor in the trigger matrix and physically surrounds the superconductor. The current surge during a fault will generate a trigger magnetic field in the series inductor to cause fast and uniform quenching of the trigger superconductor to significantly reduce burnout risk due to superconductor material non-uniformity.

  12. Optimization of superconducting flux qubit readout using near-quantum-limited amplifiers

    E-Print Network [OSTI]

    Johnson, Jedediah Edward Jensen

    2012-01-01

    junctions . . . . . . . 1.4 Superconducting QuantumInterference 1.5 Superconducting qubits . . . . . . . . .2 Superconducting flux qubits 2.1 The one-junction flux

  13. Assessment study of superconducting fault-current limiters operating at 77K

    SciTech Connect (OSTI)

    Giese, R.F. ); Runde, M. )

    1992-01-01

    The possible impact of nitrogen-cooled superconductors on the design and cost of superconducting fault-current limiters is assessed by considering the technical specifications such devices must meet and by comparing material properties of 77-K and 4-K superconductors. The main advantage of operating superconductors at 77 K is that the refrigeration operating cost is reduced by a factor of up to 25, and the refrigeration capital cost is reduced by a factor of up to 10. The heat capacity of 77 K is several orders of magnitude larger than at 4 K. This phenomenon increases conductor stability against flux jumps but makes switching from the superconducting to normal state slow and difficult. Consequently, a high critical current density, probably at least 10{sup 5} A/cm{sup 2}, is required.

  14. Assessment study of superconducting fault-current limiters operating at 77K

    SciTech Connect (OSTI)

    Giese, R.F.; Runde, M.

    1992-07-01

    The possible impact of nitrogen-cooled superconductors on the design and cost of superconducting fault-current limiters is assessed by considering the technical specifications such devices must meet and by comparing material properties of 77-K and 4-K superconductors. The main advantage of operating superconductors at 77 K is that the refrigeration operating cost is reduced by a factor of up to 25, and the refrigeration capital cost is reduced by a factor of up to 10. The heat capacity of 77 K is several orders of magnitude larger than at 4 K. This phenomenon increases conductor stability against flux jumps but makes switching from the superconducting to normal state slow and difficult. Consequently, a high critical current density, probably at least 10{sup 5} A/cm{sup 2}, is required.

  15. Proc. of the workshop on pushing the limits of RF superconductivity.

    SciTech Connect (OSTI)

    Kim, K-J., Eyberger, C., editors

    2005-04-13

    For three days in late September last year, some sixty experts in RF superconductivity from around the world came together at Argonne to discuss how to push the limits of RF superconductivity for particle accelerators. It was an intense workshop with in-depth presentations and ample discussions. There was added excitement due to the fact that, a few days before the workshop, the International Technology Recommendation Panel had decided in favor of superconducting technology for the International Linear Collider (ILC), the next major high-energy physics accelerator project. Superconducting RF technology is also important for other large accelerator projects that are either imminent or under active discussion at this time, such as the Rare Isotope Accelerator (RIA) for nuclear physics, energy recovery linacs (ERLs), and x-ray free-electron lasers. For these accelerators, the capability in maximum accelerating gradient and/or the Q value is essential to limit the length and/or operating cost of the accelerators. The technological progress of superconducting accelerators during the past two decades has been truly remarkable, both in low-frequency structures for acceleration of protons and ions as well as in high-frequency structures for electrons. The requirements of future accelerators demand an even higher level of performance. The topics of this workshop are therefore highly relevant and timely. The presentations given at the workshop contained authoritative reviews of the current state of the art as well as some original materials that previously had not been widely circulated. We therefore felt strongly that these materials should be put together in the form of a workshop proceeding. The outcome is this report, which consists of two parts: first, a collection of the scholarly papers prepared by some of the participants and second, copies of the viewgraphs of all presentations. The presentation viewgraphs, in full color, are also available from the Workshop Presentations link on the workshop's web page at http://www.aps.anl.gov/conferences/RFSCLimits/. I would like to thank all of the participants for their lively contributions to the workshop and to these proceedings, and Helen Edwards and Hasan Padamsee for their help in developing the workshop program. I also thank Cathy Eyberger, Kelly Jaje, and Renee Lanham for working very hard to take care of the administrative details, in particular Cathy for editing this report.

  16. Solid-state circuit breaker with current-limiting characteristic using a superconducting coil

    DOE Patents [OSTI]

    Boenig, H.J.

    1982-08-16

    A thyristor bridge interposes an ac source and a load. A series connected DC source and superconducting coil within the bridge biases the thyristors thereof so as to permit bidirectional ac current flow therethrough under normal operating conditions. Upon a fault condition a control circuit triggers the thyristors so as to reduce ac current flow therethrough to zero in less than two eyeles and to open the bridge thereafter. Upon a temporary overload condition the control circuit triggers the thyristors so as to limit ac current flow therethrough to an acceptable level.

  17. Solid-state circuit breaker with current limiting characteristic using a superconducting coil

    DOE Patents [OSTI]

    Boenig, Heinrich J. (Los Alamos, NM)

    1984-01-01

    A thyristor bridge interposes an ac source and a load. A series connected DC source and superconducting coil within the bridge biases the thyristors thereof so as to permit bidirectional ac current flow therethrough under normal operating conditions. Upon a fault condition a control circuit triggers the thyristors so as to reduce ac current flow therethrough to zero in less than two cycles and to open the bridge thereafter. Upon a temporary overload condition the control circuit triggers the thyristors so as to limit ac current flow therethrough to an acceptable level.

  18. Fault current limiter

    DOE Patents [OSTI]

    Darmann, Francis Anthony

    2013-10-08

    A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

  19. Fault-Current Limiter (FCL) Application in a Wind Power Plant (Poster)

    SciTech Connect (OSTI)

    Muljadi, E.; Gevorgian, V.

    2011-05-01

    This poster describes how the power system switchgear and power system protection for WPPs should be carefully designed to be compatible with the operation of conventional synchronous generators connected to the same grid.

  20. Fault current limiter with shield and adjacent cores

    DOE Patents [OSTI]

    Darmann, Francis Anthony; Moriconi, Franco; Hodge, Eoin Patrick

    2013-10-22

    In a fault current limiter (FCL) of a saturated core type having at least one coil wound around a high permeability material, a method of suppressing the time derivative of the fault current at the zero current point includes the following step: utilizing an electromagnetic screen or shield around the AC coil to suppress the time derivative current levels during zero current conditions.

  1. Implementation of Resistive Type Superconducting Fault Current Limiters in Electrical Grids: Performance Analysis and Measuring of Optimal Locations

    E-Print Network [OSTI]

    Zhang, Xiuchang; Zhong, Z; Coombs, T A

    2015-01-01

    In the past few years there has been a significant rise in the short-circuit current levels in transmission and distribution networks, it due to the increasing demands on power and the addition of sources of distributed generations. It leads to the need of integration of novel protection systems such as the superconducting fault current limiters (SFCLs), ... . SFCL models on the electric distribution networks largely rely on the insertion of a step or exponential resistance that is determined by a predefined quenching time. However, beyond the framework of these models, the study of the performance, reliability, and location strategy for the installation of sole or multiple SFCLs in power grids still lacks of proper development leading to the utter need of comprehensive and systematic studies on this issue. In this paper, we expand the scope of the aforementioned models by considering the actual behaviour of a SFCL in terms of the temperature dynamic power-law dependence between the electrical field and the c...

  2. Superconducting Spintronics

    E-Print Network [OSTI]

    Linder, Jacob; Robinson, Jason W. A.

    2015-04-02

    device functionality. Traditional studies which combine spintronics and superconductivity have mainly focused on the injection of spin-polarized quasiparticles into superconducting materials. However, a complete synergy between superconducting...

  3. SUPERCONDUCTING DEVICES

    E-Print Network [OSTI]

    Clarke, John

    2014-01-01

    communications. References Superconductor Applications: ~on all aspects of superconducting devices. IEEE Trans.on all aspects vf superconducting devices. The IBM Journal

  4. DEPOSITION OF NIOBIUM AND OTHER SUPERCONDUCTING MATERIALS WITH HIGH POWER IMPULSE MAGNETRON SPUTTERING: CONCEPT AND FIRST RESULTS

    E-Print Network [OSTI]

    Anders, Andre

    2013-01-01

    Workshop on RF Superconductivity, DESY, Hamburg, Germany,Gennaro, Physica C: Superconductivity 441 (2006) 130. [10]the Limits of RF Superconductivity, Padua, Italy, 2010. [12

  5. Superconducting wires

    SciTech Connect (OSTI)

    Lanagan, M.T.; Poeppel, R.B.; Singh, J.P.; Dos Santos, D.I.; Lumpp, J.K.; Dusek, J.T.; Goretta, K.C.

    1988-06-01

    The requirement of high critical current density has prompted extensive research on ceramic processing of high-T/sub c/ superconductors. An overview of wire fabrication techniques and the limitations they impose on component design will be presented. The effects of processing on microstructure and critical current density will also be discussed. Particle alignment has been observed in extruded samples which is attributed to high shear stresses during plastic forming. Composites of superconductor and silver in several configurations have been made with little deleterious effect on the superconducting properties. 35 refs., 2 figs., 1 tab.

  6. Continuum-Limit of the Upper Critical-Field H-Star-C2 for Superconducting Networks 

    E-Print Network [OSTI]

    Hu, Chia-Ren.

    1987-01-01

    , and T,u is the superconducting transi- tion temperature of the material at zero applied field. They checked Eq. (1) against two-dimensional square, tri- angular, and honeycomb lattices and three-dimensional simple cubic and centered cubic lattices... (s) BX tly 4k + 1+cosOg'(T) I crossing at the centers of the squares), and found that Eq. (1) holds for this case. Our third example is a square lattice with the cross- sectional areas of the horizontal strands Sl being, in gen- eral...

  7. Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters

    SciTech Connect (OSTI)

    Frank Darmann; Robert Lombaerde; Franco Moriconi; Albert Nelson

    2011-10-31

    Zenergy Power has successfully designed, built, tested, and installed in the US electrical grid a saturable reactor Fault Current Limiter. Beginning in 2007, first as SC Power Systems and from 2008 as Zenergy Power, Inc., ZP used DOE matching grant and ARRA funds to help refine the design of the saturated reactor fault current limiter. ZP ultimately perfected the design of the saturated reactor FCL to the point that ZP could reliably design a suitable FCL for most utility applications. Beginning with a very basic FCL design using 1G HTS for a coil housed in a LN2 cryostat for the DC bias magnet, the technology progressed to a commercial system that was offered for sale internationally. Substantial progress was made in two areas. First, the cryogenics cooling system progressed from a sub-cooled liquid nitrogen container housing the HTS coils to cryostats utilizing dry conduction cooling and reaching temperatures down to less than 20 degrees K. Large, round cryostats with â??warm boreâ? diameters of 1.7 meters enabled the design of large tanks to hold the AC components. Second, the design of the AC part of the FCL was refined from a six legged â??spiderâ? design to a more compact and lighter design with better fault current limiting capability. Further refinement of the flux path and core shape led to an efficient saturated reactor design requiring less Ampere-turns to saturate the core. In conclusion, the development of the saturable reactor FCL led to a more efficient design not requiring HTS magnets and their associated peripheral equipment, which yielded a more economical product in line with the electric utility industry expectations. The original goal for the DOE funding of the ZP project â??Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limitersâ? was to stimulate the HTS wire industry with, first 1G, then 2G, HTS wire applications. Over the approximately 5 years of ZPâ??s product development program, the amount of HTS wire employed per FCL and its cost as a percentage of the total FCL product content had not dropped substantially from an unsustainable level of more than 50% of the total cost of the FCL, nor had the availability increased (today the availability of 2G wire for commercial applications outside of specific partnerships with the leading 2G wire manufacturers is extremely limited). ZP had projected a very significant commercial potential for FCLs with higher performance and lower costs compared to the initial models built with 1G wire, which would come about from the widespread availability of low-cost, high-performance 2G HTS wire. The potential for 2G wires at greatly reduced performance-based prices compared to 1G HTS conductor held out the potential for the commercial production of FCLs at price and performance levels attractive to the utility industry. However, the price of HTS wire did not drop as expected and today the available quantities of 2G wire are limited, and the price is higher than the currently available supplies of 1G wire. The commercial option for ZP to provide a reliable and reasonably priced FCL to the utility industry is to employ conventional resistive conductor DC electromagnets to bias the FCL. Since the premise of the original funding was to stimulate the HTS wire industry and ZP concluded that copper-based magnets were more economical for the foreseeable future, DOE and ZP decided to mutually terminate the project.

  8. Superconducting Cable

    DOE Patents [OSTI]

    Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

    2005-03-08

    In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

  9. Superconducting Cable

    DOE Patents [OSTI]

    Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

    2005-07-22

    In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

  10. THE USE OF HIGH CURRENT DENSITY SUPERCONDUCTING COILS IN FUSION DEVICES

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    the charge rate of the superconductinp coil is limited byfor tubular cooled superconducting magnets. The use of aal. , Epoxy Resins for Superconducting Magnet Encapsulation,

  11. Limiter

    DOE Patents [OSTI]

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  12. Superconducting structure

    DOE Patents [OSTI]

    Kwon, Chuhee (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

    2003-04-01

    A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

  13. Superconducting Structure

    DOE Patents [OSTI]

    Kwon, Chuhee (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

    2005-09-13

    A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

  14. Limiter

    DOE Patents [OSTI]

    Cohen, Samuel A. (Hopewell, NJ); Hosea, Joel C. (Princeton, NJ); Timberlake, John R. (Allentown, NJ)

    1986-01-01

    A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.

  15. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01

    and R. W . BOOIll, "Superconductive Energy Storage Inducand H. A. Peterson, "Superconductive E nergy S torage forMeeting, Janua ry N. Mohan, "Superconductive Energy S torage

  16. Superconducting phase qubits

    E-Print Network [OSTI]

    Martinis, John M.

    2009-01-01

    frequency noise in dc superconducting quantum interfer- enceeld enhancement of superconductivity in ultranarrow wires.Transformed dissipation in superconducting quantum circuits.

  17. Superconductivity for Electric Systems

    E-Print Network [OSTI]

    Superconductivity Program Oak Ridge National Laboratory For: Department of Energy Office of Electricity Delivery and Energy Reliability ­ Superconductivity for Electric Systems #12;3 Control Milestones and Status ControlSuperconductivity for Electric Systems Superconductivity Program Quarterly Progress Report

  18. Superconducting magnets

    SciTech Connect (OSTI)

    Not Available

    1994-08-01

    This report discusses the following topics on superconducting magnets: D19B and -C: The next steps for a record-setting magnet; D20: The push beyond 10 T: Beyond D20: Speculations on the 16-T regime; other advanced magnets for accelerators; spinoff applications; APC materials development; cable and cabling-machine development; and high-{Tc} superconductor at low temperature.

  19. (Final Draft) Superconducting

    E-Print Network [OSTI]

    ANDAND (Final Draft) Achieving Advanced Electrical Wires From Superconducting Coatings Prepared and Development Roadmap to Achieve Electrical Wire Advancements from Superconducting Coatings (Final Draft) Edited

  20. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01

    Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances

  1. Superconductivity for Electric Systems

    E-Print Network [OSTI]

    1 Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period October 1, 2006, to December 31, 2006 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For U.S. Department of Energy Office of Electricity Delivery

  2. Superconductivity for Electric Systems

    E-Print Network [OSTI]

    Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period April 1, 2007, to June 30, 2007 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For: Department of Energy Office of Electricity Delivery

  3. QUENCHES IN LARGE SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Eberhard, P.H.

    2010-01-01

    QUENCHES IN LARGE SUPERCONDUCTING MAGNETS. P. H. Eberhard,Study of an Unprotected Superconducting Coil Going Normal,"Method for Testing Superconducting Magnets," LBL Physics

  4. Superconducting microfabricated ion traps

    E-Print Network [OSTI]

    Wang, Shannon Xuanyue

    We fabricate superconducting ion traps with niobium and niobium nitride and trap single [superscript 88]Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the ...

  5. Superconducting quantum circuits theory and application

    E-Print Network [OSTI]

    Deng, Xiuhao

    2015-01-01

    viii General theory of Superconducting cavity coupled to2.4 Decoherence in superconductingProposed circuit for superconducting qubits . . . . .

  6. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01

    A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

  7. Basic principle of superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-11-10

    The basic principle of superconductivity is suggested in this paper. There have been two vital wrong suggestions on the basic principle, one is the relation between superconductivity and the Bose-Einstein condensation (BEC), and another is the relation between superconductivity and pseudogap.

  8. Experimental Advanced Superconducting Tokamak

    E-Print Network [OSTI]

    ASIPP Experimental Advanced Superconducting Tokamak (EAST) Design, Fabrication and Assembly Weng of the project is to develop an advanced superconducting tokamak · Explore and demonstrate of steady magnets Total weight 38.7 tons, Total flux swing 10 VS Magnet system Superconducting coils; CIC conductor

  9. Superconducting Power Generation

    E-Print Network [OSTI]

    Mario Rabinowitz

    2003-02-20

    The superconducting ac generator has the greatest potential for large-scale commercial application of superconductivity that can benefit the public. Electric power is a vital ingredient of modern society, and generation may be considered to be the vital ingredient of a power system. This articles gives background, and an insight into the physics and engineering of superconducting power generation.

  10. Processing method for superconducting ceramics

    DOE Patents [OSTI]

    Bloom, Ira D. (Bolingbrook, IL); Poeppel, Roger B. (Glen Ellyn, IL); Flandermeyer, Brian K. (Cincinnati, OH)

    1993-01-01

    A process for preparing a superconducting ceramic and particularly YBa.sub.2 Cu.sub.3 O.sub.7-.delta., where .delta. is in the order of about 0.1-0.4, is carried out using a polymeric binder which decomposes below its ignition point to reduce carbon residue between the grains of the sintered ceramic and a nonhydroxylic organic solvent to limit the problems with water or certain alcohols on the ceramic composition.

  11. Protective link for superconducting coil

    DOE Patents [OSTI]

    Umans, Stephen D. (Belmont, MA)

    2009-12-08

    A superconducting coil system includes a superconducting coil and a protective link of superconducting material coupled to the superconducting coil. A rotating machine includes first and second coils and a protective link of superconducting material. The second coil is operable to rotate with respect to the first coil. One of the first and second coils is a superconducting coil. The protective link is coupled to the superconducting coil.

  12. Superconducting microfabricated ion traps

    E-Print Network [OSTI]

    Shannon X. Wang; Yufei Ge; Jaroslaw Labaziewicz; Eric Dauler; Karl Berggren; Isaac L. Chuang

    2010-12-14

    We fabricate superconducting ion traps with niobium and niobium nitride and trap single 88Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the resistance and critical current using a 4-wire measurement on the trap structure, and observing change in the rf reflection. The lowest observed heating rate is 2.1(3) quanta/sec at 800 kHz at 6 K and shows no significant change across the superconducting transition, suggesting that anomalous heating is primarily caused by noise sources on the surface. This demonstration of superconducting ion traps opens up possibilities for integrating trapped ions and molecular ions with superconducting devices.

  13. Superconductivity, Superfluidity and Holography

    E-Print Network [OSTI]

    Alberto Salvio

    2013-01-16

    This is a concise review of holographic superconductors and superfluids. We highlight some predictions of the holographic models and the emphasis is given to physical aspects rather than to the technical details, although some references to understand the latter are systematically provided. We include gapped systems in the discussion, motivated by the physics of high-temperature superconductivity. In order to do so we consider a compactified extra dimension (with radius R), or, alternatively, a dilatonic field. The first setup can also be used to model cylindrical superconductors; when these are probed by an axial magnetic field a universal property of holography emerges: while for large R (compared to the other scales in the problem) non-local operators are suppressed, leading to the so called Little-Parks periodicity, the opposite limit shows non-local effects, e.g. the uplifting of the Little-Parks periodicity. This difference corresponds in the gravity side to a Hawking-Page phase transition.

  14. Mixed normal-superconducting states in the presence of strong electric currents

    E-Print Network [OSTI]

    Mixed normal-superconducting states in the presence of strong electric currents Yaniv Almog stability. For steady-state solutions in the large limit, we prove that the superconductivity order A = A + , = - t , = ei . (1.8) 3 #12;c c i i Jin Jout Figure 1: Typical superconducting sample. The arrows denote

  15. Temperature control of Fano resonances and transmission in superconducting metamaterials

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Temperature control of Fano resonances and transmission in superconducting metamaterials V *vaf@orc.soton.ac.uk Abstract: Losses are the main evil that limits the use of metamaterials to the metamaterial structures. An exception is superconducting metamaterials, where Joule losses can be uniquely

  16. Nano-fabricated superconducting radio-frequency composites, method for producing nano-fabricated superconducting rf composites

    DOE Patents [OSTI]

    Norem, James H.; Pellin, Michael J.

    2013-06-11

    Superconducting rf is limited by a wide range of failure mechanisms inherent in the typical manufacture methods. This invention provides a method for fabricating superconducting rf structures comprising coating the structures with single atomic-layer thick films of alternating chemical composition. Also provided is a cavity defining the invented laminate structure.

  17. AC Loss Analysis on the Superconducting Coupling Magnet in MICE

    E-Print Network [OSTI]

    Wu, Hong

    2009-01-01

    of Cryogenics and Superconductivity Technology, Harbinof cryogenics and superconductivity engineering technologyof Cryogenics and Superconductivity Technology, “Engineering

  18. Philosophy 26 High Temperature Superconductivity

    E-Print Network [OSTI]

    Callender, Craig

    Philosophy 26 High Temperature Superconductivity By Ohm's Law, resistance will dim. Low temperature superconductivity was discovered in 1911 by Heike was explained by BCS theory. BCS theory explains superconductivity microscopically

  19. Superconductive imaging surface magnetometer

    DOE Patents [OSTI]

    Overton, Jr., William C. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM); Flynn, Edward R. (Los Alamos, NM)

    1991-01-01

    An improved pick-up coil system for use with Superconducting Quantum Interference Device gradiometers and magnetometers involving the use of superconducting plates near conventional pick-up coil arrangements to provide imaging of nearby dipole sources and to deflect environmental magnetic noise away from the pick-up coils. This allows the practice of gradiometry and magnetometry in magnetically unshielded environments. One embodiment uses a hemispherically shaped superconducting plate with interior pick-up coils, allowing brain wave measurements to be made on human patients. another embodiment using flat superconducting plates could be used in non-destructive evaluation of materials.

  20. Superconducting VAR control

    DOE Patents [OSTI]

    Boenig, Heinrich J. (Los Alamos, NM); Hassenzahl, William V. (Piedmont, CA)

    1982-01-01

    Static VAR control means employing an asymmetrically controlled Graetz bridge and a superconducting direct current coil having low losses and low cost characteristics.

  1. Alexei Abrikosov and Superconductivity

    Office of Scientific and Technical Information (OSTI)

    quantum liquids. ... Superconductivity is the ability of some materials to conduct electricity without resistance when they are chilled to extremely low temperatures....

  2. Superconducting shielded core reactor with reduced AC losses

    DOE Patents [OSTI]

    Cha, Yung S.; Hull, John R.

    2006-04-04

    A superconducting shielded core reactor (SSCR) operates as a passive device for limiting excessive AC current in a circuit operating at a high power level under a fault condition such as shorting. The SSCR includes a ferromagnetic core which may be either closed or open (with an air gap) and extends into and through a superconducting tube or superconducting rings arranged in a stacked array. First and second series connected copper coils each disposed about a portion of the iron core are connected to the circuit to be protected and are respectively wound inside and outside of the superconducting tube or rings. A large impedance is inserted into the circuit by the core when the shielding capability of the superconducting arrangement is exceeded by the applied magnetic field generated by the two coils under a fault condition to limit the AC current in the circuit. The proposed SSCR also affords reduced AC loss compared to conventional SSCRs under continuous normal operation.

  3. Search for: superconduct* | DOE PAGES

    Office of Scientific and Technical Information (OSTI)

    superconduct* Find + Advanced Search Advanced Search All Fields: superconduct* Title: Full Text: Bibliographic Data: Creator Author: Name Name ORCID Search Authors Type: All...

  4. SciTech Connect: superconduct*

    Office of Scientific and Technical Information (OSTI)

    superconduct* Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: superconduct* Semantic Semantic Term Title: Full Text: Bibliographic Data: Creator ...

  5. Superconducting Magnet Division

    E-Print Network [OSTI]

    Gupta, Ramesh

    Superconducting Magnet Division Permanent Magnet Designs with Large Variations in Field Strength the residual field of the magnetized bricks by concentrating flux lines at the iron pole. Low Field Design Medium Field Design Superconducting Magnet Division Dipole and Quadrupole Magnets for RHIC e

  6. Superconductivity of magnesium diboride

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

    Bud’ko, Sergey L.; Canfield, Paul C.

    2015-07-15

    Over the past 14 years MgB2 has gone from a startling discovery to a promising, applied superconductor. In our article we present a brief overview of the synthesis and the basic superconducting properties of this remarkable compound. Specifically, the effect of pressure, substitutions and neutron irradiation on superconducting properties are discussed.

  7. Superconducting Radiofrequency (SRF) Accelerator Cavities

    ScienceCinema (OSTI)

    Reece, Charlie

    2014-05-22

    Charlie Reece, an accelerator technology scientist, explains how superconducting radiofrequency accelerator cavities work.

  8. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Yonit Hochberg; Yue Zhao; Kathryn M. Zurek

    2015-04-27

    We propose and study a new class of of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with all astrophysical and terrestrial constraints could be detected by such detectors with a moderate size exposure.

  9. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Hochberg, Yonit; Zurek, Kathryn M

    2015-01-01

    We propose and study a new class of of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with all astrophysical and terrestrial constraints could be detected by such detectors with a moderate size exposure.

  10. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Yonit Hochberg; Yue Zhao; Kathryn M. Zurek

    2015-11-11

    We propose and study a new class of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off of free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with terrestrial and cosmological/astrophysical constraints could be detected by such detectors with a moderate size exposure.

  11. 6.763 Applied Superconductivity, Fall 2001

    E-Print Network [OSTI]

    Orlando, Terry P.

    Phenomenological approach to superconductivity, with emphasis on superconducting electronics. Electrodynamics of superconductors, London's model, and flux quantization. Josephson Junctions and superconducting quantum ...

  12. Superconducting solenoids for the MICE channel

    E-Print Network [OSTI]

    2003-01-01

    IEEE Transactions on Applied Superconductivity 13, No. 2 S.SUPERCONDUCTING SOLENOIDS FOR THE MICE CHANNEL* M. A. Green,describes the channel of superconducting solenoids for the

  13. Superconducting Circuitry for Quantum Electromechanical Systems

    E-Print Network [OSTI]

    Matthew D. LaHaye; Francisco Rouxinol; Yu Hao; Seung-Bo Shim; Elinor K. Irish

    2015-04-11

    Superconducting systems have a long history of use in experiments that push the frontiers of mechanical sensing. This includes both applied and fundamental research, which at present day ranges from quantum computing research and efforts to explore Planck-scale physics to fundamental studies on the nature of motion and the quantum limits on our ability to measure it. In this paper, we first provide a short history of the role of superconducting circuitry and devices in mechanical sensing, focusing primarily on efforts in the last decade to push the study of quantum mechanics to include motion on the scale of human-made structures. This background sets the stage for the remainder of the paper, which focuses on the development of quantum electromechanical systems (QEMS) that incorporate superconducting quantum bits (qubits), superconducting transmission line resonators and flexural nanomechanical elements. In addition to providing the motivation and relevant background on the physical behavior of these systems, we discuss our recent efforts to develop a particular type of QEMS that is based upon the Cooper-pair box (CPB) and superconducting coplanar waveguide (CPW) cavities, a system which has the potential to serve as a testbed for studying the quantum properties of motion in engineered systems.

  14. Introduction to Color Superconductivity

    E-Print Network [OSTI]

    G. Nardulli

    2006-10-23

    At high nuclear density and small temperature, due to the asymptotic freedom property of Quantum ChromoDynamics and to the existence of an attractive channel in the color interaction, diquark condensates might be formed. Since these condensates break the color gauge symmetry, this phenomenon has the name of color superconductivity. In the last few years this has become a very active field of research. While a direct experimental test is still missing, color superconductivity might have implications in astrophysics because for some compact stars, e.g. pulsars, the baryon densities necessary for color superconductivity can probably be reached.

  15. Superconducting active impedance converter

    DOE Patents [OSTI]

    Ginley, David S. (Albuquerque, NM); Hietala, Vincent M. (Placitas, NM); Martens, Jon S. (Albuquerque, NM)

    1993-01-01

    A transimpedance amplifier for use with high temperature superconducting, other superconducting, and conventional semiconductor allows for appropriate signal amplification and impedance matching to processing electronics. The amplifier incorporates the superconducting flux flow transistor into a differential amplifier configuration which allows for operation over a wide temperature range, and is characterized by high gain, relatively low noise, and response times less than 200 picoseconds over at least a 10-80 K. temperature range. The invention is particularly useful when a signal derived from either far-IR focal plane detectors or from Josephson junctions is to be processed by higher signal/higher impedance electronics, such as conventional semiconductor technology.

  16. IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 14, NO. 2, JUNE 2004 883 Design and Cooling Characteristic Results

    E-Print Network [OSTI]

    Chang, Ho-Myung

    IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 14, NO. 2, JUNE 2004 883 Design and Cooling-cooled cryogenic cooling system for 1.2 kV/80 A inductive Superconducting Fault Current Limiter (SFCL was supported by a grant from the Center for Applied Superconductivity Technology of the 21st Century Frontier R

  17. Superconducting thermoelectric generator

    DOE Patents [OSTI]

    Metzger, J.D.; El-Genk, M.S.

    1996-01-01

    An apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.

  18. Superconducting thermoelectric generator

    DOE Patents [OSTI]

    Metzger, J.D.; El-Genk, M.S.

    1998-05-05

    An apparatus and method for producing electricity from heat is disclosed. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device. 4 figs.

  19. Superconducting thermoelectric generator

    DOE Patents [OSTI]

    Metzger, John D. (Eaton's Neck, NY); El-Genk, Mohamed S. (Albuquerque, NM)

    1998-01-01

    An apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.

  20. Superconducting transmission line particle detector

    DOE Patents [OSTI]

    Gray, Kenneth E. (Naperville, IL)

    1989-01-01

    A microvertex particle detector for use in a high energy physic collider including a plurality of parallel superconducting thin film strips separated from a superconducting ground plane by an insulating layer to form a plurality of superconducting waveguides. The microvertex particle detector indicates passage of a charged subatomic particle by measuring a voltage pulse measured across a superconducting waveguide caused by the transition of the superconducting thin film strip from a superconducting to a non-superconducting state in response to the passage of a charged particle. A plurality of superconducting thin film strips in two orthogonal planes plus the slow electromagnetic wave propogating in a superconducting transmission line are used to resolve N.sup.2 ambiguity of charged particle events.

  1. Superconducting transmission line particle detector

    DOE Patents [OSTI]

    Gray, K.E.

    1988-07-28

    A microvertex particle detector for use in a high energy physic collider including a plurality of parallel superconducting thin film strips separated from a superconducting ground plane by an insulating layer to form a plurality of superconducting waveguides. The microvertex particle detector indicates passage of a charged subatomic particle by measuring a voltage pulse measured across a superconducting waveguide caused by the transition of the superconducting thin film strip from a superconducting to a non- superconducting state in response to the passage of a charged particle. A plurality of superconducting thin film strips in two orthogonal planes plus the slow electromagnetic wave propagating in a superconducting transmission line are used to resolve N/sup 2/ ambiguity of charged particle events. 6 figs.

  2. Superconducting radiofrequency window assembly

    DOE Patents [OSTI]

    Phillips, Harry L. (Seaford, VA); Elliott, Thomas S. (Yorktown, VA)

    1997-01-01

    The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.

  3. Superconductive radiofrequency window assembly

    DOE Patents [OSTI]

    Phillips, Harry Lawrence (Seaford, VA); Elliott, Thomas S. (Yorktown, VA)

    1998-01-01

    The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.

  4. High temperature interfacial superconductivity

    DOE Patents [OSTI]

    Bozovic, Ivan (Mount Sinai, NY); Logvenov, Gennady (Port Jefferson Station, NY); Gozar, Adrian Mihai (Port Jefferson, NY)

    2012-06-19

    High-temperature superconductivity confined to nanometer-scale interfaces has been a long standing goal because of potential applications in electronic devices. The spontaneous formation of a superconducting interface in bilayers consisting of an insulator (La.sub.2CuO.sub.4) and a metal (La.sub.1-xSr.sub.xCuO.sub.4), neither of which is superconducting per se, is described. Depending upon the layering sequence of the bilayers, T.sub.c may be either .about.15 K or .about.30 K. This highly robust phenomenon is confined to within 2-3 nm around the interface. After exposing the bilayer to ozone, T.sub.c exceeds 50 K and this enhanced superconductivity is also shown to originate from a 1 to 2 unit cell thick interfacial layer. The results demonstrate that engineering artificial heterostructures provides a novel, unconventional way to fabricate stable, quasi two-dimensional high T.sub.c phases and to significantly enhance superconducting properties in other superconductors. The superconducting interface may be implemented, for example, in SIS tunnel junctions or a SuFET.

  5. Superconducting Quantum Computing without Switches

    E-Print Network [OSTI]

    Marc J. Feldman; Xingxiang Zhou

    2002-11-25

    This paper presents a very simple architecture for a large-scale superconducting quantum computer. All of the SQUID qubits are fixed-coupled to a single large superconducting loop.

  6. Relativistic mechanism of superconductivity

    E-Print Network [OSTI]

    H. Y. Cui

    2002-12-17

    According to the theory of relativity, the relativistic Coulomb's force between an electron pair is composed of two parts, the main part is repulsive, while the rest part can be attractive in certain situations. Thus the relativistic attraction of an electron pair provides an insight into the mechanism of superconductivity. In superconductor, there are, probably at least, two kinds of collective motions which can eliminate the repulsion between two electrons and let the attraction being dominant, the first is the combination of lattice and electron gas, accounting for traditional superconductivity; the second is the electron gas themselves, accounting for high $T_c$ superconductivity. In usual materials, there is a good balance between the repulsion and attraction of an electron pair, the electrons are regarded as free electrons so that Fermi gas theory plays very well. But in some materials, when the repulsion dominates electron pairs, the electron gas will has a behavior opposite to superconductivity. In the present paper the superconducting states are discussed in terms of relativistic quantum theory in details, some significant results are obtained including quantized magnetic flux, London equation, Meissner effect and Josephson effect.

  7. Interplay of superconductivity, magnetism, and density waves in rare-earth tritellurides and iron-based superconducting materials

    E-Print Network [OSTI]

    Zocco, Diego Andrés

    2011-01-01

    B. Superconductivity . . . . . . . . . . . . . . . . .IV Superconductivity and Magnetism in Iron-PnictideSearch for Pressure Induced Superconductivity in Undoped Ce-

  8. Superconductivity and Magnetism: Materials Properties

    E-Print Network [OSTI]

    .g. within high-Tc superconductivity, magnetic superconductors, MgB2, CMR materials, nanomagnetism and spin#12;#12;Superconductivity and Magnetism: Materials Properties and Developments #12;Copyright 2003 Risø National Laboratory Roskilde, Denmark ISBN 87-550-3244-3 ISSN 0907-0079 #12;Superconductivity

  9. Nonlinear terahertz superconducting plasmonics

    SciTech Connect (OSTI)

    Wu, Jingbo; Liang, Lanju; Jin, Biaobing E-mail: tonouchi@ile.osaka-u.ac.jp Kang, Lin; Xu, Weiwei; Chen, Jian; Wu, Peiheng E-mail: tonouchi@ile.osaka-u.ac.jp; Zhang, Caihong; Kawayama, Iwao; Murakami, Hironaru; Tonouchi, Masayoshi E-mail: tonouchi@ile.osaka-u.ac.jp; Wang, Huabing

    2014-10-20

    Nonlinear terahertz (THz) transmission through subwavelength hole array in superconducting niobium nitride (NbN) film is experimentally investigated using intense THz pulses. The good agreement between the measurement and numerical simulations indicates that the field strength dependent transmission mainly arises from the nonlinear properties of the superconducting film. Under weak THz pulses, the transmission peak can be tuned over a frequency range of 145 GHz which is attributed to the high kinetic inductance of 50?nm-thick NbN film. Utilizing the THz pump-THz probe spectroscopy, we study the dynamic process of transmission spectra and demonstrate that the transition time of such superconducting plasmonic device is within 5 ps.

  10. Orbit Spaces in Superconductivity

    E-Print Network [OSTI]

    Vittorino Talamini

    2006-07-30

    In the framework of Landau theory of phase transitions one is interested to describe all the possible low symmetry ``superconducting'' phases allowed for a given superconductor crystal and to determine the conditions under which this crystal undergoes a phase transition. These problems are best described and analyzed in the orbit space of the high symmetry group of the ``normal, non-superconducting'' phase of the crystal. In this article it is worked out a simple example concerning superconductivity, that shows the P-matrix method to determine the equations and inequalities defining the orbit space and its stratification. This approach is of general validity and can be used in all physical problems that make use of invariant functions, as long as the symmetry group is compact.

  11. Superconductivity at Any Temperature

    E-Print Network [OSTI]

    Anber, Mohamed M; Sabancilar, Eray; Shaposhnikov, Mikhail

    2015-01-01

    We construct a 2+1 dimensional model that sustains superconductivity at all temperatures. This is achieved by introducing a Chern Simons mixing term between two Abelian gauge fields A and Z. The superfluid is described by a complex scalar charged under Z, whereas a sufficiently strong magnetic field of A forces the superconducting condensate to form at all temperatures. In fact, at finite temperature, the theory exhibits Berezinsky-Kosterlitz-Thouless phase transition due to proliferation of topological vortices admitted by our construction. However, the critical temperature is proportional to the magnetic field of A, and thus, the phase transition can be postponed to high temperatures by increasing the strength of the magnetic field. This model can be a step towards realizing the long sought room temperature superconductivity.

  12. Superconducting metamaterials and qubits

    E-Print Network [OSTI]

    B. L. T. Plourde; Haozhi Wang; Francisco Rouxinol; M. D. LaHaye

    2015-05-05

    Superconducting thin-film metamaterial resonators can provide a dense microwave mode spectrum with potential applications in quantum information science. We report on the fabrication and low-temperature measurement of metamaterial transmission-line resonators patterned from Al thin films. We also describe multiple approaches for numerical simulations of the microwave properties of these structures, along with comparisons with the measured transmission spectra. The ability to predict the mode spectrum based on the chip layout provides a path towards future designs integrating metamaterial resonators with superconducting qubits.

  13. Superconducting thermoelectric generator

    DOE Patents [OSTI]

    Metzger, J.D.; El-Genk, M.S.

    1994-01-01

    Thermoelectricity is produced by applying a temperature differential to dissimilar electrically conducting or semiconducting materials, thereby producing a voltage that is proportional to the temperature difference. Thermoelectric generators use this effect to directly convert heat into electricity; however, presently-known generators have low efficiencies due to the production of high currents which in turn cause large resistive heating losses. Some thermoelectric generators operate at efficiencies between 4% and 7% in the 800{degrees} to 1200{degrees}C range. According to its major aspects and bradly stated, the present invention is an apparatus and method for producing electricity from heat. In particular, the invention is a thermoelectric generator that juxtaposes a superconducting material and a semiconducting material - so that the superconducting and the semiconducting materials touch - to convert heat energy into electrical energy without resistive losses in the temperature range below the critical temperature of the superconducting material. Preferably, an array of superconducting material is encased in one of several possible configurations within a second material having a high thermal conductivity, preferably a semiconductor, to form a thermoelectric generator.

  14. Hybrid superconducting neutron detectors

    SciTech Connect (OSTI)

    Merlo, V.; Lucci, M.; Ottaviani, I.; Salvato, M.; Cirillo, M.; Scherillo, A.; Celentano, G.; Pietropaolo, A.

    2015-03-16

    A neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction, {sup 10}B?+?n?????+?{sup 7}Li, with ? and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T?=?8?K and current-biased below the critical current I{sub c}, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40?mV are measured while the bias current can be properly modulated to bring the strip back to the superconducting state, thus resetting the detector. Measurements on the counting rate of the device are presented and the basic physical features of the detector are discussed.

  15. Langmuir vacuum and superconductivity

    SciTech Connect (OSTI)

    Veklenko, B. A.

    2012-06-15

    It is shown that, in the 'jelly' model of cold electron-ion plasma, the interaction between electrons and the quantum electromagnetic vacuum of Langmuir waves involves plasma superconductivity with an energy gap proportional to the energy of the Langmuir quantum.

  16. Superconducting Magnet Division

    E-Print Network [OSTI]

    Ohta, Shigemi

    Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R.6 A gun collectors gun Combined Horizontal and Vertical Corrector Design Both types of dipole correctors. Gupta, M. Anerella, W. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone, S. Plate, A

  17. Superconducting magnetic energy storage (SMES) program, January 1-December 31, 1981

    SciTech Connect (OSTI)

    Rogers, J.D. (comp.)

    1982-02-01

    Work reported is on the development of a 30 MJ superconducting magnetic energy storage (SMES) unit for use by the Bonneville Power Administration (BPA) to stabilize power oscillations on their Pacific AC Intertie. The 30 MJ superconducting coil manufacture was completed. Design of the seismic mounting of the coil to the nonconducting dewar lid and a concrete foundation is complete. The superconducting application VAR (SAVAR) control study indicated a low economic advantage and the SAVAR program was terminated. An economic and technological evaluation of superconducting fault current limiter (SFCL) was completed and the results are reported.

  18. IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 17, NO. 2, JUNE 2007 1863 Development of 220 V/300 A Class Non-Inductive

    E-Print Network [OSTI]

    Chang, Ho-Myung

    IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 17, NO. 2, JUNE 2007 1863 Development of 220 V-inductive winding type superconducting fault current limiter (SFCL) is being developed. The target of the second-inductively wound coils in se- ries using a 2G high temperature superconducting (HTS) wire and it was tested in sub

  19. A gradient flow approach to an evolution problem arising in superconductivity

    E-Print Network [OSTI]

    Serfaty, Sylvia

    A gradient flow approach to an evolution problem arising in superconductivity Luigi Ambrosio for the evolution of the vortex-density in a superconductor. We treat the case of a bounded domain where vortices in studying the following "mean-field model" (also called hydrodynamic limit) for superconductivity which

  20. Superconductivity: the Gift that Keeps on Giving

    E-Print Network [OSTI]

    Goldberg, Bennett

    Superconductivity: the Gift that Keeps on Giving Superconductivity, first discovered recently the discovery of high superconducting transition temperatures in the ceramic copper oxides has superconductors. In the underdoped or pseudogap phase of the cuprate superconductors, a significant portion

  1. The superconducting solenoid magnets for MICE

    E-Print Network [OSTI]

    Green, Michael A.

    2002-01-01

    IEEE Transactions on Applied Superconductivity 13, No. 2 M.M. A. Green and J. M. Rey, “Superconducting Solenoids for anHigh Current Density Superconducting Solenoid Magnets for

  2. Superconducting vortex pinning with artificially prepared nanostructures

    E-Print Network [OSTI]

    Rosen, Yaniv Jacob

    E. Dubin, Physica C: Superconductivity 369, 21 (2002). R. D.P. G. De Gennes, Superconductivity of Metals and Alloys (W.Schuller, Journal of Superconductivity and Novel Magnetism

  3. Superconductivity in graphite intercalation compounds

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

    Smith, Robert P. [Univ. of Cambridge (United Kingdom); Dean, Mark P. M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Weller, Thomas E. [Univ. College of London (United Kingdom); Howard, Christopher A. [Univ. College of London (United Kingdom); Rahnejat, Kaveh C. [Univ. College of London (United Kingdom); Saxena, Siddharth S. [Univ. of Cambridge (United Kingdom); Ellerby, Mark [Univ. College of London (United Kingdom)

    2015-07-01

    The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s This paper recontextualizes the field in light of the discovery of superconductivity in CaC? and YbC? in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how this relates to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.

  4. Superconductivity in graphite intercalation compounds

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

    Smith, Robert P.; Weller, Thomas E.; Howard, Christopher A.; Dean, Mark P. M.; Rahnejat, Kaveh C.; Saxena, Siddharth S.; Ellerby, Mark

    2015-02-26

    This study examines the field of superconductivity in the class of materials known as graphite intercalation compounds which has a history dating back to the 1960s. This paper recontextualizes the field in light of the discovery of superconductivity in CaC? and YbC? in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how this relates to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic statesmore »and phonon modes are most important for superconductivity and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.« less

  5. Model of Antiferromagnetic Superconductivity

    E-Print Network [OSTI]

    Geoffrey L. Sewell

    2015-09-28

    We present a simple model that supports superconductive and antiferromagnetic ordering. The model consists of a system of electrons on a simple cubic lattice that move by tunnel effect and interact via antiferromagnetic Ising spin couplings and short range repulsions: these include infinitely strong Hubbard forces that prevent double occupancy of any lattice site. Hence, under the filling condition of one electron per site and at sufficiently low temperature, the system is an antiferromagnetic Mott insulator. However, when holes are created by suitable doping, they are mobile charge carriers. We show that, at low concentration, their interactions induced by the above interelectronic ones lead to Schafroth pairing. Hence, under certain plausible but unproved assumptions, the model exhibits the off-diagonal long range order that characterises superconductivity, while retaining the antiferromagnetic ordering.

  6. Competition between singlet and triplet superconductivity

    E-Print Network [OSTI]

    Tian De Cao; Tie Bang Wang

    2009-10-04

    The competition between singlet and triplet superconductivity is examined in consideration of correlations on an extended Hubbard model. It is shown that the triplet superconductivity may not be included in the common Hubbard model since the strong correlation favors the singlet superconductivity, and thus the triplet superconductivity should be induced by the electron-phonon interaction and the ferromagnetic exchange interaction. We also present a superconducting qualification with which magnetism is unbeneficial to superconductivity.

  7. Superconducting magnet wire

    DOE Patents [OSTI]

    Schuller, Ivan K. (Woodridge, IL); Ketterson, John B. (Evanston, IL); Banerjee, Indrajit (San Jose, CA)

    1986-01-01

    A superconducting tape or wire with an improved critical field is formed of alternating layers of a niobium-containing superconductor such as Nb, NbTi, Nb.sub.3 Sn or Nb.sub.3 Ge with a thickness in the range of about 0.5-1.5 times its coherence length, supported and separated by layers of copper with each copper layer having a thickness in the range of about 170-600 .ANG..

  8. Equilibrium Distributions and Superconductivity

    E-Print Network [OSTI]

    Ashot Vagharshakyan

    2011-06-07

    In this article two models for charges distributions are discussed. On the basis of our consideration we put different points of view for stationary state. We prove that only finite energy model for charges' distribution and well-known variation principle explain some well-known experimental results. A new model for superconductivity was suggested, too. In frame of that model some characteristic experimental results for superconductors is possible to explain.

  9. Topological confinement and superconductivity

    SciTech Connect (OSTI)

    Al-hassanieh, Dhaled A [Los Alamos National Laboratory; Batista, Cristian D [Los Alamos National Laboratory

    2008-01-01

    We derive a Kondo Lattice model with a correlated conduction band from a two-band Hubbard Hamiltonian. This mapping allows us to describe the emergence of a robust pairing mechanism in a model that only contains repulsive interactions. The mechanism is due to topological confinement and results from the interplay between antiferromagnetism and delocalization. By using Density-Matrix-Renormalization-Group (DMRG) we demonstrate that this mechanism leads to dominant superconducting correlations in aID-system.

  10. Superconducting VAR control. [Patent application

    DOE Patents [OSTI]

    Boenig, H.J.; Hassenzahl, W.V.

    1980-12-05

    Static VAR control means are described employing an asymmetrically controlled Graetz bridge and a superconducting direct current coil having low losses and low cost characteristics.

  11. Superconducting magnet development in Japan

    SciTech Connect (OSTI)

    Yasukochi, K.

    1983-05-01

    The present state of R and D works on the superconducting magnet and its applications in Japan are presented. On electrical rotating machines, 30 MVA superconducting synchronous rotary condenser (Mitsubishi and Fuji) and 50 MVA generator are under construction. Two ways of ship propulsion by superconducting magnets are developing. A superconducting magnetically levitated and linear motor propelled train ''MAGLEV'' was developed by the Japan National Railways (JNR). The superconducting magnet development for fusion is the most active field in Japan. The Cluster Test program has been demonstrated on a 10 T Nb/sub 3/Sn coil and the first coil of Large Coil Task in IEA collaboration has been constructed and the domestic test was completed in JAERI. These works are for the development of toroidal coils of the next generation tokamak machine. R and D works on superconducting ohmic heating coil are in progress in JAERI and ETL. The latter group has constructed 3.8 MJ pulsed coil. A high ramp rate of changing field in pulsed magnet, 200 T/s, has been tested successfully. High Energy Physics Laboratory (KEK) are conducting active works. The superconducting ..mu.. meson channel and ..pi.. meson channel have been constructed and are operating successfully. KEK has also a project of big accelerator named ''TRISTAN'', which is similar to ISABELLE project of BNL. Superconducting synchrotron magnets are developed for this project. The development of superconducting three thin wall solenoid has been started. One of them, CDF, is progressing under USA-Japan collaboration.

  12. Superconductivity and Superfluidity

    E-Print Network [OSTI]

    B. V. Vasiliev

    2013-10-31

    Currently there is a common belief that the explanation of superconductivity phenomenon lies in understanding the mechanism of the formation of electron pairs. Paired electrons, however, cannot form a superconducting condensate spontaneously. These paired electrons perform disorderly zero-point oscillations and there are no force of attraction in their ensemble. In order to create a unified ensemble of particles, the pairs must order their zero-point fluctuations so that an attraction between the particles appears. As a result of this ordering of zero-point oscillations in the electron gas, superconductivity arises. This model of condensation of zero-point oscillations creates the possibility of being able to obtain estimates for the critical parameters of elementary superconductors, which are in satisfactory agreement with the measured data. On the another hand, the phenomenon of superfluidity in He-4 and He-3 can be similarly explained, due to the ordering of zero-point fluctuations. It is therefore established that both related phenomena are based on the same physical mechanism.

  13. Superconducting dark energy

    E-Print Network [OSTI]

    Shi-Dong Liang; Tiberiu Harko

    2015-04-10

    Based on the analogy with superconductor physics we consider a scalar-vector-tensor gravitational model, in which the dark energy action is described by a gauge invariant electromagnetic type functional. By assuming that the ground state of the dark energy is in a form of a condensate with the U(1) symmetry spontaneously broken, the gauge invariant electromagnetic dark energy can be described in terms of the combination of a vector and of a scalar field (corresponding to the Goldstone boson), respectively. The gravitational field equations are obtained by also assuming the possibility of a non-minimal coupling between the cosmological mass current and the superconducting dark energy. The cosmological implications of the dark energy model are investigated for a Friedmann-Robertson-Walker homogeneous and isotropic geometry for two particular choices of the electromagnetic type potential, corresponding to a pure electric type field, and to a pure magnetic field, respectively. The time evolution of the scale factor, matter energy density and deceleration parameter are obtained for both cases, and it is shown that in the presence of the superconducting dark energy the Universe ends its evolution in an exponentially accelerating vacuum de Sitter state. By using the formalism of the irreversible thermodynamic processes for open systems we interpret the generalized conservation equations in the superconducting dark energy model as describing matter creation. The particle production rates, the creation pressure and the entropy evolution are explicitly obtained.

  14. Flavor Superconductivity & Superfluidity

    E-Print Network [OSTI]

    Matthias Kaminski

    2010-02-25

    In these lecture notes we derive a generic holographic string theory realization of a p-wave superconductor and superfluid. For this purpose we also review basic D-brane physics, gauge/gravity methods at finite temperature, key concepts of superconductivity and recent progress in distinct realizations of holographic superconductors and superfluids. Then we focus on a D3/D7-brane construction yielding a superconducting or superfluid vector-condensate. The corresponding gauge theory is 3+1-dimensional N=2 supersymmetric Yang-Mills theory with SU(N) color and SU(2) flavor symmetry. It shows a second order phase transition to a phase in which a U(1) subgroup of the SU(2) symmetry is spontaneously broken and typical superconductivity signatures emerge, such as a conductivity (pseudo-)gap and the Meissner-Ochsenfeld effect. Condensates of this nature are comparable to those recently found experimentally in p-wave superconductors such as a ruthenate compound. A string picture of the pairing mechanism and condensation is given using the exact knowledge of the corresponding field theory degrees of freedom.

  15. Magnetically leviated superconducting bearing

    DOE Patents [OSTI]

    Weinberger, Bernard R. (Avon, CT); Lynds, Jr., Lahmer (Glastonbury, CT)

    1993-01-01

    A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.

  16. Superconducting Magnets for a Muon Collider

    E-Print Network [OSTI]

    Green, M.A.

    1996-01-01

    IEEE Transactions on Applied Superconductivity 3, No. 1,pMAG-544 LBL-38398 UC-414 Superconducting Magnets for a Muonsections, the nominal superconductor plus matrix current

  17. THE TECHNOLOGY OF SUPERCONDUCTING ACCELERATOR DIPOLES

    E-Print Network [OSTI]

    Hassenzahl, W.V.

    2010-01-01

    properties of practical superconductors,2 2. their sta-winding from the superconductive to the resistive state. *I. II. III. IV. V. Superconducting Materials Conductor Matri

  18. High-Temperature Superconducting Composite Conductors

    DOE Patents [OSTI]

    Holesinger, Terry G. (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM); Arendt, Paul N. (Los Alamos, NM); Groves, James R. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Ayala, Alicia (Santa Fe, NM)

    2005-01-18

    Copper or excess copper is added to one or more layers of a superconducting composite structure to reduce migration of copper form a copper based superconducting layer.

  19. Optimization of superconducting tiling pattern for superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1996-01-01

    An apparatus and method for reducing magnetic field inhomogeneities which produce rotational loss mechanisms in high temperature superconducting magnetic bearings. Magnetic field inhomogeneities are reduced by dividing high temperature superconducting structures into smaller structures, and arranging the smaller structures into tiers which stagger the magnetic field maximum locations of the smaller structures.

  20. Optimization of superconducting tiling pattern for superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.

    1996-09-17

    An apparatus and method for reducing magnetic field inhomogeneities which produce rotational loss mechanisms in high temperature superconducting magnetic bearings are disclosed. Magnetic field inhomogeneities are reduced by dividing high temperature superconducting structures into smaller structures, and arranging the smaller structures into tiers which stagger the magnetic field maximum locations of the smaller structures. 20 figs.

  1. Cosmological constraints on superconducting dark energy models

    E-Print Network [OSTI]

    Zoltán Keresztes; László Á. Gergely; Tiberiu Harko; Shi-Dong Liang

    2015-09-01

    We consider cosmological tests of a scalar-vector-tensor gravitational model, in which the dark energy is included in the total action through a gauge invariant, electromagnetic type contribution. The ground state of dark energy, corresponding to a constant potential $V$ is a Bose-Einstein type condensate with spontaneously broken U(1) symmetry. In another words dark energy appears as a massive vector field emerging from a superposition of a massless vector and a scalar field, the latter corresponding to the Goldstone boson. Two particular cosmological models, corresponding to pure electric and pure magnetic type potentials, respectively are confronted with Type IA Supernovae and Hubble parameter data. In the electric case good fit is obtained along a narrow inclined stripe in the $\\Omega _{m}-\\Omega _{V}$ parameter plane, which includes the $\\Lambda $CDM limit. The other points on this admissible region represent superconducting dark energy as a sum of a cosmological constant and a time-evolving contribution. In the magnetic case the cosmological test selects either i) parameter ranges of the superconducting dark energy allowing for the standard baryonic plus dark matter or ii) a unified superconducting dark matter and dark energy model, additionally including only the baryonic sector. The cosmological data is best matched when the matter decouples from both the scalar and vector sectors of dark energy, hence favoring matter conservation as opposed to particle creation in an irreversible process.

  2. Power superconducting power transmission cable

    DOE Patents [OSTI]

    Ashworth, Stephen P. (Cambridge, GB)

    2003-01-01

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  3. High critical current superconducting tapes

    DOE Patents [OSTI]

    Holesinger, Terry G. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

    2003-09-23

    Improvements in critical current capacity for superconducting film structures are disclosed and include the use of a superconducting RE-BCO layer including a mixture of rare earth metals, e.g., yttrium and europium, where the ratio of yttrium to europium in the RE-BCO layer ranges from about 3 to 1 to from about 1.5 to 1.

  4. Superconducting Topological Insulators

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With Livermore National Lab on Supercomputing Click toSuperconducting

  5. Superconducting Topological Insulators

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With Livermore National Lab on Supercomputing ClickSuperconducting

  6. Superconductivity Conference Held

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With Livermore National Lab on SupercomputingSuperconductivity

  7. Weak Measurement and Feedback in Superconducting Quantum Circuits

    E-Print Network [OSTI]

    K. W. Murch; R. Vijay; I. Siddiqi

    2015-07-16

    We describe the implementation of weak quantum measurements in superconducting qubits, focusing specifically on transmon type devices in the circuit quantum electrodynamics architecture. To access this regime, the readout cavity is probed with on average a single microwave photon. Such low-level signals are detected using near quantum-noise-limited superconducting parametric amplifiers. Weak measurements yield partial information about the quantum state, and correspondingly do not completely project the qubit into an eigenstate. As such, we use the measurement record to either sequentially reconstruct the quantum state at a given time, yielding a quantum trajectory, or to close a direct quantum feedback loop, stabilizing Rabi oscillations indefinitely.

  8. Weak Measurement and Feedback in Superconducting Quantum Circuits

    E-Print Network [OSTI]

    K. W. Murch; R. Vijay; I. Siddiqi

    2015-07-28

    We describe the implementation of weak quantum measurements in superconducting qubits, focusing specifically on transmon type devices in the circuit quantum electrodynamics architecture. To access this regime, the readout cavity is probed with on average a single microwave photon. Such low-level signals are detected using near quantum-noise-limited superconducting parametric amplifiers. Weak measurements yield partial information about the quantum state, and correspondingly do not completely project the qubit into an eigenstate. As such, we use the measurement record to either sequentially reconstruct the quantum state at a given time, yielding a quantum trajectory, or to close a direct quantum feedback loop, stabilizing Rabi oscillations indefinitely.

  9. The integration of cryogenic cooling systems with superconducting electronic systems

    E-Print Network [OSTI]

    Green, Michael A.

    2011-01-01

    applications for superconductivity have low heat loads in aTransactions on Applied Superconductivity t I, P 2615, (Cooling Systems With Superconducting Electronic Systems M.

  10. RECENT ADVANCES IN THE TECHNOLOGY OF SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.E.

    2010-01-01

    Current Multipoles in Superconducting Accelerator Magnets."Utilization of the Superconducting Super Collider, Snowmass,Field Harmonics in Superconducting Accelerator Magnets,·

  11. Cryogenic Tests of the g-2 Superconducting Solenoid Magnet System

    E-Print Network [OSTI]

    Jia, L.X.

    2011-01-01

    in IEEE Transactions on Applied Superconductivity 5. No.F. Krienen et al.. "The Superconducting Inflector Dipole forTransactions on Applied Superconductivity 5. No.2 (1995) G.

  12. A superconducting focusing solenoid for the neutrino factory linear accelerator

    E-Print Network [OSTI]

    Green, Michael A.; Lebedev, V.; Strauss, B.P.

    2001-01-01

    et al, “The Role of Superconductivity and Cryogenics in theA Superconducting Focusing Solenoid for the Neutrino FactoryAcceleration Cells for the Superconducting Linac. Shown in

  13. Compressed Sensing Quantum Process Tomography for Superconducting Quantum Gates

    E-Print Network [OSTI]

    Rodionov, Andrey

    2014-01-01

    2.2 Review of superconducting qubits . . . . . .State Tomography for superconducting qubits 3.1 The idea ofPossible new effects in superconductive tunnelling”, Physics

  14. Fabrication, Testing and Modeling of the MICE Superconducting Spectrometer Solenoids

    E-Print Network [OSTI]

    Virostek, S.P.

    2010-01-01

    IEEE Transactions on Applied Superconductivity 15, No. 2, p.IEEE Transactions on Applied Superconductivity 15, No. 2, p.AND MODELING OF THE MICE SUPERCONDUCTING SPECTROMETER

  15. Quantum State Protection and Transfer Using Superconducting Qubits

    E-Print Network [OSTI]

    Keane, Kyle Michael

    2012-01-01

    relaxation . . . . . . . . .1.5 Superconducting ? ux-biasedCorrection Algorithms for Superconducting Qubits,” APS Marchand correction for superconducting qubits,” Phys. Rev. A,

  16. Preliminary Test Results for the MICE Spectrometer Superconducting Solenoids

    E-Print Network [OSTI]

    Virostek, Steve P.

    2009-01-01

    Transactions on Applied Superconductivity 19, No. 3 MICETransactions on Applied Superconductivity 15, No. 2, p 1259,Transactions on Applied Superconductivity 18, No. 2, p 937,

  17. Los Alamos scientists see new mechanism for superconductivity

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

    New mechanism for superconductivity Los Alamos scientists see new mechanism for superconductivity Researchers have posited an explanation for superconductivity that may open the...

  18. On-chip superconducting microwave circulator from synthetic rotation

    E-Print Network [OSTI]

    Joseph Kerckhoff; Kevin Lalumière; Benjamin J. Chapman; Alexandre Blais; K. W. Lehnert

    2015-02-21

    We analyze the design of a potential replacement technology for the commercial ferrite circulators that are ubiquitous in contemporary quantum superconducting microwave experiments. The lossless, lumped element design is capable of being integrated on chip with other superconducting microwave devices, thus circumventing the many performance-limiting aspects of ferrite circulators. The design is based on the dynamic modulation of DC superconducting microwave quantum interference devices (SQUIDs) that function as nearly linear, tunable inductors. The connection to familiar ferrite-based circulators is a simple frame boost in the internal dynamics' equation of motion. In addition to the general, schematic analysis, we also give an overview of many considerations necessary to achieve a practical design with a tunable center frequency in the 4-8 GHz frequency band, a bandwidth of 240 MHz, reflections at the -20 dB level, and a maximum signal power of approximately order 100 microwave photons per inverse bandwidth.

  19. Dynamics of an Ion Coupled to a Parametric Superconducting Circuit

    E-Print Network [OSTI]

    Dvir Kafri; Prabin Adhikari; Jacob M. Taylor

    2015-04-15

    Superconducting circuits and trapped ions are promising architectures for quantum information processing. However, the natural frequencies for controlling these systems -- radio frequency ion control and microwave domain superconducting qubit control -- make direct Hamiltonian interactions between them weak. In this paper we describe a technique for coupling a trapped ion's motion to the fundamental mode of a superconducting circuit. We do this by applying a carefully modulated external magnetic flux to the circuit. In conjunction with a non-linear element (Josephson junction), this gives the circuit an effective time-dependent inductance. We then show how to tune the external flux to generate a resonant coupling between circuit and ion's motional mode, and discuss the limitations of this approach compared to using a time-dependent capacitance.

  20. Radio Broadcasts from Superconducting Strings

    E-Print Network [OSTI]

    Yi-Fu Cai; Eray Sabancilar; Daniele A. Steer; Tanmay Vachaspati

    2012-05-14

    Superconducting cosmic strings can give transient electromagnetic signatures that we argue are most evident at radio frequencies. We investigate the three different kinds of radio bursts from cusps, kinks, and kink-kink collisions on superconducting strings. We find that the event rate is dominated by kink bursts in a range of parameters that are of observational interest, and can be quite high (several a day at 1 Jy flux) for a canonical set of parameters. In the absence of events, the search for radio transients can place stringent constraints on superconducting cosmic strings.

  1. A superconducting-nanowire 3-terminal electronic device

    E-Print Network [OSTI]

    Adam N. McCaughan; Karl K. Berggren

    2014-03-25

    In existing superconducting electronic systems, Josephson junctions play a central role in processing and transmitting small-amplitude electrical signals. However, Josephson-junction-based devices have a number of limitations including: (1) sensitivity to magnetic fields, (2) limited gain, (3) inability to drive large impedances, and (4) difficulty in controlling the junction critical current (which depends sensitively on sub-Angstrom-scale thickness variation of the tunneling barrier). Here we present a nanowire-based superconducting electronic device, which we call the nanocryotron (nTron), that does not rely on Josephson junctions and can be patterned from a single thin film of superconducting material with conventional electron-beam lithography. The nTron is a 3-terminal, T-shaped planar device with a gain of ~20 that is capable of driving impedances of more than 100 k{\\Omega}, and operates in typical ambient magnetic fields at temperatures of 4.2K. The device uses a localized, Joule-heated hotspot formed in the gate to modulate current flow in a perpendicular superconducting channel. We have characterized the nTron, matched it to a theoretical framework, and applied it both as a digital logic element in a half-adder circuit, and as a digital amplifier for superconducting nanowire single-photon detectors pulses. The nTron has immediate applications in classical and quantum communications, photon sensing and astronomy, and its performance characteristics make it compatible with existing superconducting technologies. Furthermore, because the hotspot effect occurs in all known superconductors, we expect the design to be extensible to other materials, providing a path to digital logic, switching, and amplification in high-temperature superconductors.

  2. Superconducting magnetic coil

    DOE Patents [OSTI]

    Aized, D.; Schwall, R.E.

    1999-06-22

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.

  3. Superconducting magnetic energy storage

    SciTech Connect (OSTI)

    Hassenzahl, W.

    1988-08-01

    Recent programmatic developments in Superconducting Magnetic Energy Storage (SMES) have prompted renewed and widespread interest in this field. In mid 1987 the Defense Nuclear Agency, acting for the Strategic Defense Initiative Office, issued a request for proposals for the design and construction of SMES Engineering Test Model (ETM). Two teams, one led by Bechtel and the other by Ebasco, are now engaged in the first phase of the development of a 10 to 20 MWhr ETM. This report presents the rationale for energy storage on utility systems, describes the general technology of SMES, and explains the chronological development of the technology. The present ETM program is outlined; details of the two projects for ETM development are described in other papers in these proceedings. The impact of high T/sub c/ materials on SMES is discussed. 69 refs., 3 figs., 3 tabs.

  4. Superconducting energy storage

    SciTech Connect (OSTI)

    Giese, R.F.

    1993-10-01

    This report describes the status of energy storage involving superconductors and assesses what impact the recently discovered ceramic superconductors may have on the design of these devices. Our description is intended for R&D managers in government, electric utilities, firms, and national laboratories who wish an overview of what has been done and what remains to be done. It is assumed that the reader is acquainted with superconductivity, but not an expert on the topics discussed here. Indeed, it is the author`s aim to enable the reader to better understand the experts who may ask for the reader`s attention, support, or funding. This report may also inform scientists and engineers who, though expert in related areas, wish to have an introduction to our topic.

  5. Superconductivity from correlated hopping

    SciTech Connect (OSTI)

    Batista, C.D.; Lema, F.; Aligia, A.A. [Comision Nacional de Energia Atomica, Centro Atomico Bariloche and Instituto Balseiro, 8400 Bariloche (Argentina)] [Comision Nacional de Energia Atomica, Centro Atomico Bariloche and Instituto Balseiro, 8400 Bariloche (Argentina)

    1995-09-01

    We consider a chain described by a next-nearest-neighbor hopping combined with a nearest-neighbor spin flip. In two dimensions this three-body term arises from a mapping of the three-band Hubbard model for CuO{sub 2} planes to a generalized {ital t}-{ital J} model and for large O-O hopping favors resonance-valence-bond superconductivity of predominantly {ital d}-wave symmetry. Solving the ground-state and low-energy excitations by analytical and numerical methods we find that the chain is a Luther-Emery liquid with correlation exponent {ital K}{sub {rho}}=(2{minus}{ital n}){sup 2}/2, where {ital n} is the particle density.

  6. Fabrication of arrays of nano-superconducting quantum interfernce devices using a double-angle processing approach

    E-Print Network [OSTI]

    Roediger, Peter

    2014-01-01

    incommensurate area superconducting quantum interferencearray of incommensurate superconducting quantum interferencetransition-temperature superconducting quantum interference

  7. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.; Mulcahy, T.M.

    1998-03-03

    A mixed-mu superconducting bearing is disclosed including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure. 9 figs.

  8. On the theory of superconductivity 

    E-Print Network [OSTI]

    Cheng, Kai-Chia

    The phenomenon of superconductivity has so for defied all attempts of explanation since it was first discovered in 1911. Although two phenomenological theories have been put forward and proved very successful, yet no atomic theories based on quantum...

  9. EIS-0138: Superconducting Super Collider

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this EIS to analyze the potential environmental impacts of constructing the Superconducting Super Collider, a large proton accelerator, at each of seven alternative locations.

  10. Scaling of Superconducting Switches for Extraction of Magnetic Energy

    E-Print Network [OSTI]

    Ballarino, A

    2010-01-01

    In certain cases it is necessary to extract the energy from a superconducting magnet when it quenches, in order to limit the heat generated by the event and thus prevent irreversible damage. This is usually achieved by opening a contact breaker across a resistor in the circuit feeding the magnet. For the heavy currents used to excite large magnets such switches incorporate sophisticated devices to limit arcing during the operation; besides being quite large and expensive, such switches have a limited lifetime. It is therefore interesting to consider the use of superconducting switches to perform this function, the advantage being that such switches would (i) not require maintenance and (ii) would be housed within the cryogenic environment of the magnet, and thus avoid permanent diversion of the current in and out of that environment to the mechanical switch (which operates at room temperature). However, practical switches for such an application are made up of superconductor in a metal matrix, and it is conve...

  11. PHYSICAL REVIEW B 91, 214508 (2015) Superconducting spin-valve effect and triplet superconductivity

    E-Print Network [OSTI]

    Fominov, Yakov

    2015-01-01

    PHYSICAL REVIEW B 91, 214508 (2015) Superconducting spin-valve effect and triplet superconductivity 12 June 2015) We report magnetic and superconducting properties of the modified spin-valve system Co theoretical description of the superconducting spin-valve effect and of the manifestation of the long

  12. Electrothermal simulation of superconducting nanowire avalanche photodetectors

    E-Print Network [OSTI]

    Marsili, Francesco

    We developed an electrothermal model of NbN superconducting nanowire avalanche photodetectors (SNAPs) on sapphire substrates. SNAPs are single-photon detectors consisting of the parallel connection of N superconducting ...

  13. Recent Developments in High Temperature Superconductivity 

    E-Print Network [OSTI]

    Hor, P. H.

    1988-01-01

    New material systems and the experimental progress of high temperature superconductivity are briefly reviewed. We examine both oxides and non-oxides which exhibit stable and/or unstable superconductivity at high temperatures....

  14. HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01

    D. C. 'Niobium-Titanium Superconducting Material s ', in S.Nb -Ti and Nb3Sn superconductors. , •• ,""" s. S. Clamp, Tie14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.

  15. Superconducting Partnership with Readiness Review Update

    E-Print Network [OSTI]

    1 Superconducting Partnership with Industry: Readiness Review Update Mike Gouge, ORNL Steve Ashworth, LANL Paul Bakke, DOE-Golden DOE 2004 Superconductivity Peer Review July 27-29, 2004 #12;2 SPI

  16. ORNL/HTSPC-10 ORNL Superconducting

    E-Print Network [OSTI]

    ORNL/HTSPC-10 ORNL Superconducting Technology Program for Electric Power Systems Annual Report http://www.doe.gov/bridge #12;ORNL/HTSPC-10 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC POWER

  17. Design of a Superconducting Quantum Computer

    E-Print Network [OSTI]

    Vallette, Bruno

    Design of a Superconducting Quantum Computer John Martinis UC Santa Barbara Is it really possible theory i d hi *error-correction and architecture* 4) Xmon superconducting qubits) p g q integrated

  18. AMORPHOUS MOLYBDENUM SILICON SUPERCONDUCTING THIN FILMS

    E-Print Network [OSTI]

    Bosworth, D.; Sahonta, S.-L.; Hadfield, R. H.; Barber, Z. H.

    2015-01-01

    Amorphous superconductors have become attractive candidate materials for superconducting nanowire single-photon detectors due to their ease of growth, homogeneity and competitive superconducting properties. To date the majority of devices have been...

  19. A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER

    E-Print Network [OSTI]

    O'Donnell, Tom

    A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER FOR PRODUCTION OF NEUTRON-RICH NUCLEI ( 136 Xe Superconducting Cyclotron Laboratory's weekly \\Green Sheet," 30 July 1999 #12; c Thomas W. O'Donnell 2000 All

  20. A Synergy of Novel Experiments, Materials Science, Fundamental Physics, and Superconducting Magnets

    E-Print Network [OSTI]

    Godeke, Arno

    2007-01-01

    Fundamental Physics Superconducting Magnets Yields: Accuraterecord setting superconducting magnet systems ITER, NMRScience, Fundamental Physics, and Superconducting Magnets

  1. Superconducting Cable Termination

    DOE Patents [OSTI]

    Sinha, Uday K. (Carrollton, GA); Tolbert, Jerry (Newnan, GA)

    2005-08-30

    Disclosed is a termination that connects high temperature superconducting (HTS) cable immersed in pressurized liquid nitrogen to high voltage and neutral (shield) external bushings at ambient temperature and pressure. The termination consists of a splice between the HTS power (inner) and shield (outer) conductors and concentric copper pipes which are the conductors in the termination. There is also a transition from the dielectric tape insulator used in the HTS cable to the insulators used between and around the copper pipe conductors in the termination. At the warm end of the termination the copper pipes are connected via copper braided straps to the conventional warm external bushings which have low thermal stresses. This termination allows for a natural temperature gradient in the copper pipe conductors inside the termination which enables the controlled flashing of the pressurized liquid coolant (nitrogen) to the gaseous state. Thus the entire termination is near the coolant supply pressure and the high voltage and shield cold bushings, a highly stressed component used in most HTS cables, are eliminated. A sliding seal allows for cable contraction as it is cooled from room temperature to ˜72-82 K. Seals, static vacuum, and multi-layer superinsulation minimize radial heat leak to the environment.

  2. Improved superconducting magnet wire

    DOE Patents [OSTI]

    Schuller, I.K.; Ketterson, J.B.

    1983-08-16

    This invention is directed to a superconducting tape or wire composed of alternating layers of copper and a niobium-containing superconductor such as niobium of NbTi, Nb/sub 3/Sn or Nb/sub 3/Ge. In general, each layer of the niobium-containing superconductor has a thickness in the range of about 0.05 to 1.5 times its coherence length (which for Nb/sub 3/Si is 41 A) with each copper layer having a thickness in the range of about 170 to 600 A. With the use of very thin layers of the niobium composition having a thickness within the desired range, the critical field (H/sub c/) may be increased by factors of 2 to 4. Also, the thin layers of the superconductor permit the resulting tape or wire to exhibit suitable ductility for winding on a magnet core. These compositions are also characterized by relatively high values of critical temperature and therefore will exhibit a combination of useful properties as superconductors.

  3. A unified theory of superconductivity

    E-Print Network [OSTI]

    Xiuqing Huang

    2008-09-22

    In this paper, we study the reliability of BCS theory as a scientific explanation of the mystery of superconductivity. It is shown clearly that the phonon-mediated BCS theory is fundamentally incorrect. Two kinds of glues, pairing (pseudogap) glue and superconducting glue, are suggested based on a real space Coulomb confinement effect. The scenarios provide a unified explanation of the pairing symmetry, pseudogap and superconducting states, charge stripe order, spin density wave (SDW), checkerboard-type charge-ordered phase, magic doping fractions and vortex structures in conventional and unconventional (the high-Tc cuprates and MgB2) superconductors. The theory agrees with the existence of a pseudogap in high-temperature superconductors, while no pseudogap feature could be observed in MgB2 and most of the conventional superconductors. Our results indicate that the superconducting phase can coexist with a inclined hexagonal vortex lattice in pure MgB2 single crystal with a charge carrier density ps=1.49*10^{22}/cm^{3}. Finally, the physical reasons why the good conductors (for example, Ag, Au, and Cu) and the overdoped high-Tc superconductors are non-superconducting are also explored.

  4. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

    Goren, Y.; Mahale, N.K.

    1996-08-06

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles. 6 figs.

  5. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

    Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

    1996-01-01

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

  6. Superconductive articles including cerium oxide layer

    DOE Patents [OSTI]

    Wu, Xin D. (Greenbelt, MD); Muenchausen, Ross E. (Espanola, NM)

    1993-01-01

    A ceramic superconductor comprising a metal oxide substrate, a ceramic high temperature superconductive material, and a intermediate layer of a material having a cubic crystal structure, said layer situated between the substrate and the superconductive material is provided, and a structure for supporting a ceramic superconducting material is provided, said structure comprising a metal oxide substrate, and a layer situated over the surface of the substrate to substantially inhibit interdiffusion between the substrate and a ceramic superconducting material deposited upon said structure.

  7. Superconducting PM undiffused machines with stationary superconducting coils

    DOE Patents [OSTI]

    Hsu, John S.; Schwenterly, S. William

    2004-03-02

    A superconducting PM machine has a stator, a rotor and a stationary excitation source without the need of a ferromagnetic frame which is cryogenically cooled for operation in the superconducting state. PM material is placed between poles on the rotor to prevent leakage or diffusion of secondary flux before reaching the main air gap, or to divert PM flux where it is desired to weaken flux in the main air gap. The PM material provides hop-along capability for the machine in the event of a fault condition.

  8. Topical Review Progress in superconducting metamaterials

    E-Print Network [OSTI]

    Anlage, Steven

    Topical Review Progress in superconducting metamaterials Philipp Jung1,2 , Alexey V Ustinov1 in the development and applications of superconducting metamaterials. The review is organized in terms of several distinct advantages and unique properties brought to the metamaterials field by superconductivity

  9. Comment on "d id0 Chiral Superconductivity

    E-Print Network [OSTI]

    Wu, Zhigang

    Comment on "d þ id0 Chiral Superconductivity in Bilayer Silicene" In Ref. [1], Liu et al, their random-phase-approximation analysis sug- gests that the system is superconducting with the Cooper pairs, they claim that a high superconducting critical temperature is possible due to the tunable Fermi pocket via

  10. Superconductivity in iron compounds G. R. Stewart

    E-Print Network [OSTI]

    Wu, Zhigang

    of the superconductivity in this new class of compounds. These iron pnictide and chalcogenide (FePn/Ch) superconductors-phonon coupled ``conventional'' superconductors. Clearly, superconductivity and magnetism or magnetic of magnetism and superconductivity in FePn/Ch superconductors 1606 D. Tc and TS=TSDW versus pressure 1607 1

  11. Superconducting wire with improved strain characteristics

    DOE Patents [OSTI]

    Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (E. Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

    1982-01-01

    A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improves the strain characteristics of the wire.

  12. Superconducting wire with improved strain characteristics

    DOE Patents [OSTI]

    Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (East Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

    1982-01-01

    A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improve the strain characteristics of the wire.

  13. Strain tolerant microfilamentary superconducting wire

    DOE Patents [OSTI]

    Finnemore, D.K.; Miller, T.A.; Ostenson, J.E.; Schwartzkopf, L.A.; Sanders, S.C.

    1993-02-23

    A strain tolerant microfilamentary wire capable of carrying superconducting currents is provided comprising a plurality of discontinuous filaments formed from a high temperature superconducting material. The discontinuous filaments have a length at least several orders of magnitude greater than the filament diameter and are sufficiently strong while in an amorphous state to withstand compaction. A normal metal is interposed between and binds the discontinuous filaments to form a normal metal matrix capable of withstanding heat treatment for converting the filaments to a superconducting state. The geometry of the filaments within the normal metal matrix provides substantial filament-to-filament overlap, and the normal metal is sufficiently thin to allow supercurrent transfer between the overlapped discontinuous filaments but is also sufficiently thick to provide strain relief to the filaments.

  14. Freely oriented portable superconducting magnet

    DOE Patents [OSTI]

    Schmierer, Eric N. (Los Alamos, NM); Prenger, F. Coyne (Los Alamos, NM); Hill, Dallas D. (Los Alamos, NM)

    2010-01-12

    A freely oriented portable superconducting magnet is disclosed. Coolant is supplied to the superconducting magnet from a repository separate from the magnet, enabling portability of the magnet. A plurality of support assemblies structurally anchor and thermally isolate the magnet within a thermal shield. A plurality of support assemblies structurally anchor and thermally isolate the thermal shield within a vacuum vessel. The support assemblies restrain movement of the magnet resulting from energizing and cooldown, as well as from changes in orientation, enabling the magnet to be freely orientable.

  15. Free-standing oxide superconducting articles

    DOE Patents [OSTI]

    Wu, X.D.; Muenchausen, R.E.

    1993-12-14

    A substrate-free, free-standing epitaxially oriented superconductive film including a layer of a template material and a layer of a ceramic superconducting material is provided together with a method of making such a substrate-free ceramic superconductive film by coating an etchable material with a template layer, coating the template layer with a layer of a ceramic superconductive material, coating the layer of ceramic superconductive material with a protective material, removing the etchable material by an appropriate means so that the etchable material is separated from a composite structure including the template layer.

  16. Cosmological constraints on superconducting dark energy models

    E-Print Network [OSTI]

    Keresztes, Zoltán; Harko, Tiberiu; Liang, Shi-Dong

    2015-01-01

    We consider cosmological tests of a scalar-vector-tensor gravitational model, in which the dark energy is included in the total action through a gauge invariant, electromagnetic type contribution. The ground state of dark energy, corresponding to a constant potential $V$ is a Bose-Einstein type condensate with spontaneously broken U(1) symmetry. In another words dark energy appears as a massive vector field emerging from a superposition of a massless vector and a scalar field, the latter corresponding to the Goldstone boson. Two particular cosmological models, corresponding to pure electric and pure magnetic type potentials, respectively are confronted with Type IA Supernovae and Hubble parameter data. In the electric case good fit is obtained along a narrow inclined stripe in the $\\Omega _{m}-\\Omega _{V}$ parameter plane, which includes the $\\Lambda $CDM limit. The other points on this admissible region represent superconducting dark energy as a sum of a cosmological constant and a time-evolving contribution...

  17. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  18. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, Vincent M. (Placitas, NM); Martens, Jon S. (Sunnyvale, CA); Zipperian, Thomas E. (Albuquerque, NM)

    1995-01-01

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs). Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics.

  19. Stress dependent oxidation of sputtered niobium and effects on superconductivity

    SciTech Connect (OSTI)

    David Henry, M. Wolfley, Steve; Monson, Todd; Clark, Blythe G.; Shaner, Eric; Jarecki, Robert

    2014-02-28

    We report on the suppression of room temperature oxidation of DC sputtered niobium films and the effects upon the superconductive transition temperature, T{sub c}. Niobium was sputter-deposited on silicon dioxide coated 150?mm wafers and permitted to oxidize at room temperature and pressure for up to two years. Resistivity and stress measurements indicate that tensile films greater than 400?MPa resist bulk oxidation with measurements using transmission electron microscope, electron dispersive X-ray spectroscopy, x-ray photoelectric spectroscopy, and secondary ion mass spectrometry confirming this result. Although a surface oxide, Nb{sub 2}O{sub 5}, consumed the top 6–10?nm, we measure less than 1 at. % oxygen and nitrogen in the bulk of the films after the oxidation period. T{sub c} measurements using a SQUID magnetometer indicate that the tensile films maintained a T{sub c} approaching the dirty superconductive limit of 8.4?K after two years of oxidation while maintaining room temperature sheet resistance. This work demonstrates that control over niobium film stress during deposition can prevent bulk oxidation by limiting the vertical grain boundaries ability to oxidize, prolonging the superconductive properties of sputtered niobium when exposed to atmosphere.

  20. STATUS OF THE SPALLATION NEUTRON SOURCE SUPERCONDUCTING RF FACILITIES

    SciTech Connect (OSTI)

    Stout, Daniel S [ORNL] [ORNL; Assadi, Saeed [ORNL] [ORNL; Campisi, Isidoro E [ORNL] [ORNL; Casagrande, Fabio [ORNL] [ORNL; Crofford, Mark T [ORNL] [ORNL; DeVan, Bill [ORNL] [ORNL; Hardek, Thomas W [ORNL] [ORNL; Henderson, Stuart D [ORNL] [ORNL; Howell, Matthew P [ORNL] [ORNL; Kang, Yoon W [ORNL] [ORNL; Geng, Xiaosong [ORNL] [ORNL; Stone Jr, William C [ORNL] [ORNL; Strong, William Herb [ORNL] [ORNL; Williams, Derrick C [ORNL] [ORNL; Wright, Paul Alan [ORNL] [ORNL

    2007-01-01

    The Spallation Neutron Source (SNS) project was completed with only limited superconducting RF (SRF) facilities installed as part of the project. A concerted effort has been initiated to install the infrastructure and equipment necessary to maintain and repair the superconducting Linac, and to support power upgrade research and development (R&D). Installation of a Class10/100/10,000 cleanroom and outfitting of the test cave with RF, vacuum, controls, personnel protection and cryogenics systems is underway. A horizontal cryostat, which can house a helium vessel/cavity and fundamental power coupler for full power, pulsed testing, is being procured. Equipment for cryomodule assembly and disassembly is being procured. This effort, while derived from the experience of the SRF community, will provide a unique high power test capability as well as long term maintenance capabilities. This paper presents the current status and the future plans for the SNS SRF facilities.

  1. Superconducting Cable Having A Felexible Former

    DOE Patents [OSTI]

    Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

    2005-03-15

    In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

  2. Superconducting Cable Having A Flexible Former

    DOE Patents [OSTI]

    Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

    2005-08-30

    In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

  3. Quadratic superconducting cosmic strings revisited

    E-Print Network [OSTI]

    Mustapha Azreg-Aïnou

    2008-02-22

    It has been shown that 5-dimensional general relativity action extended by appropriate quadratic terms admits a singular superconducting cosmic string solution. We search for cosmic strings endowed with similar and extended physical properties by directly integrating the non-linear matrix field equations thus avoiding the perturbative approach by which we constructed the above-mentioned \\textsl{exact} solution. The most general superconducting cosmic string, subject to some constraints, will be derived and shown to be mathematically \\textsl{unique} up to linear coordinate transformations mixing its Killing vectors. The most general solution, however, is not globally equivalent to the old one due to the existence of Killing vectors with closed orbits.

  4. Ten questions and answers about superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2012-11-13

    This work answers the basic questions of superconductivity in a question-and-answer format. We extend a basic hypothesis to various superconductors. This hypothesis is that superconductivity requires that the pairing gap locates around the Fermi level. On the basis of this hypothesis our calculations give the so-called three factor theory with which some key problems of the high temperature superconductivity are explained.

  5. Superconducting thin films on potassium tantalate substrates

    DOE Patents [OSTI]

    Feenstra, Roeland (Oak Ridge, TN); Boatner, Lynn A. (Oak Ridge, TN)

    1992-01-01

    A superconductive system for the lossless transmission of electrical current comprising a thin film of superconducting material Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x epitaxially deposited upon a KTaO.sub.3 substrate. The KTaO.sub.3 is an improved substrate over those of the prior art since the it exhibits small lattice constant mismatch and does not chemically react with the superconducting film.

  6. Effective theory of color superconductivity

    E-Print Network [OSTI]

    Deog Ki Hong

    2007-07-17

    We briefly review an effective theory of QCD at high baryon density, describing the relevant modes near the Fermi surface. The high density effective theory has properties of reparametrization invariance and gauge invariance, maintained in a subtle way. It also has a positive measure, allowing lattice simulations at high baryon density. We then apply it to gapless superconductors and discuss recent proposals to resolve the magnetic instability of gapless superconductivity.

  7. Reverse circling supercurrents along a superconducting ring

    E-Print Network [OSTI]

    Tian De Cao

    2012-01-21

    The reason why high temperature superconductivity has been being debated is that many basic ideas in literatures are wrong. This work shows that the magnetic flux quantum in a superconducting ring have been inaccurately explained in fact, thus we suggest a reinterpretation of the magnetic flux quantum in a superconducting ring on the basis of the translations of pairs. We also predict that the internal and external surface of a superconducting tube have the reverse circling supercurrents. This means that a more thick tube could trap a larger amount of flux. Both the magnetic flux quantum and the reverse circling supercurrents could not be found with the London equation.

  8. MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; SOLID STATE...

    Office of Scientific and Technical Information (OSTI)

    Open problems in condensed matter physics, 1987 Falicov, L.M. 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; SOLID STATE PHYSICS; RESEARCH PROGRAMS;...

  9. Superconducting Magnet Technology for Future Hadron Colliders

    E-Print Network [OSTI]

    Scanlan, R.M.

    2011-01-01

    Trans. on Applied Superconductivity, 5 (1995), J.R. Millersummer study on superconductingdevices and acceleratorsGeneral. Advanced Superconductors (IGC). Waterbury.

  10. Superconductive articles including cerium oxide layer

    DOE Patents [OSTI]

    Wu, X.D.; Muenchausen, R.E.

    1993-11-16

    A ceramic superconductor comprising a metal oxide substrate, a ceramic high temperature superconductive material, and a intermediate layer of a material having a cubic crystal structure, said layer situated between the substrate and the superconductive material is provided, and a structure for supporting a ceramic superconducting material is provided, said structure comprising a metal oxide substrate, and a layer situated over the surface of the substrate to substantially inhibit interdiffusion between the substrate and a ceramic superconducting material deposited upon said structure. 7 figures.

  11. New Advance in SuperConducting Materials

    ScienceCinema (OSTI)

    None

    2010-01-08

    Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laborator...  

  12. Light Induced Superconductivity | Stanford Synchrotron Radiation...

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

    Light Induced Superconductivity Wednesday, August 5, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Daniele Nicoletti, Max Planck Institute for the Structure and...

  13. Superconducting inductive displacement detection of a microcantilever

    SciTech Connect (OSTI)

    Vinante, A., E-mail: anvinante@fbk.eu [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy)

    2014-07-21

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100??T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2?K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  14. Testing gravitational physics with superconducting gravimeters

    E-Print Network [OSTI]

    Sachie Shiomi

    2009-02-24

    Superconducting gravimeters are the most sensitive instruments to measure surface gravity changes at low frequencies. Currently, about twenty five superconducting gravimeters are operating in the world and their global network has been developed. We investigate possible applications of the superconducting gravimeters to tests of gravitational physics. Previous experimental searches for spatial anisotropies in the gravitational constant G and for gravitational waves, performed with gravimeters in 1960's to 1970's, can be improved by applications of the current superconducting gravimeters. Also, we describe other proposed applications of testing the universality of free-fall and searching for composition-dependent dilatonic waves, and discuss future works necessary for these geophysical tests.

  15. A potential Rosetta Stone of high temperature superconductivity...

    Office of Science (SC) Website

    for the high temperature superconductivity. Summary Superconductivity enables the flow of electricity without any loss of energy, but this extremely-low temperature...

  16. Distinct superconducting states in the pressure-induced metallic...

    Office of Scientific and Technical Information (OSTI)

    Distinct superconducting states in the pressure-induced metallic structures of the nominal semimetal Bi4Te3 Citation Details In-Document Search Title: Distinct superconducting...

  17. Spin Torques in Magnetic and Superconducting Tunnel Junctions

    E-Print Network [OSTI]

    Hoffman, Silas Eli

    2012-01-01

    Proximity Effects at Superconducting Interfaces . . . . . .of spin-triplet superconductivity in Co-based JosephsonExchange Field in Superconductor- Ferromagnet Structures. ”

  18. Estimating the Cost of Large Superconducting Thin Solenoid Magnets

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01

    W. C. T. Stoddart, Superconductivity Conference Proceedings,Powell, Applied Superconductivity p 346, (1972). Appliedpure aluminum stabilized superconductor. The cost of this

  19. FORCED TWO PHASE HELIUM COOLING OF LARGE SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    DIAMETER TPC THIN SUPERCONDUCTING SOLENOID . 'i.A. Green,an Aluminum Stabilized Superconductor", Cryogenics 17, Vol.and Construction of a Superconducting Stabilized Aluminum

  20. Planar superconducting resonators with internal quality factors above one million

    E-Print Network [OSTI]

    Martinis, John M.

    Planar superconducting resonators with internal quality factors above one million A. Megrant,1,2 C criti- cal elements for superconducting electromagnetic radiation detectors,1 quantum memories,2

  1. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Theand breakage of the superconductor. The UPA circuit melted

  2. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01

    IEEE Transactions on Applied Superconductivty 15, No. 2, p274 Progress on the Superconducting Magnets for the MICETransactions on Applied Superconductivity 13, No. 2 p 1373 (

  3. A Superconducting transformer system for high current cable testing

    E-Print Network [OSTI]

    Godeke, A.

    2010-01-01

    A Superconducting Transformer System for High Current CableDC) superconducting transformer system for the high currentsuperconducting cables. The transformer consists of a core-

  4. The superconducting properties of two classes of iron-based materials have been studied in

    E-Print Network [OSTI]

    Weston, Ken

    The superconducting properties of two classes of iron-based materials have been studied in high Jc define the applications limit of any superconductor. We found that Tc and Hc2 of Ba1-xKxFe2As2 can. 98, 042509 (2011) High field performances in iron-based superconductors Gregory S. Boebinger

  5. Exotic Superconductivity in Correlated Electron Systems

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

    Mu, Gang; Sandu, Viorel; Li, Wei; Shen, Bing

    2015-05-25

    Over the past decades, the search for high-Tc superconductivity (SC) and its novel superconducting mechanisms is one of the most challenging tasks of condensed matter physicists and material scientists, wherein the most striking achievement is the discovery of high-c and unconventional superconductivity in strongly correlated 3d-electron systems, such as cuprates and iron pnictides/chalcogenides. Those exotic superconductors display the behaviors beyond the scope of the BCS theory (in the SC states) and the Landau-Fermi liquid theory (in the normal states). In general, such exotic superconductivity can be seen as correlated electron systems, where there are strong interplays among charge, spin, orbital,more »and lattice degrees of freedom. Thus, we focus on the exotic superconductivity in materials with correlated electrons in the present special issue.« less

  6. STRIPES AND SUPERCONDUCTIVITY IN CUPRATE SUPERCONDUCTORS

    SciTech Connect (OSTI)

    TRANQUADA, J.M.

    2005-08-22

    One type of order that has been observed to compete with superconductivity in cuprates involves alternating charge and antiferromagnetic stripes. Recent neutron scattering studies indicate that the magnetic excitation spectrum of a stripe-ordered sample is very similar to that observed in superconducting samples. In fact, it now appears that there may be a universal magnetic spectrum for the cuprates. One likely implication of this universal spectrum is that stripes of a dynamic form are present in the superconducting samples. On cooling through the superconducting transition temperature, a gap opens in the magnetic spectrum, and the weight lost at low energy piles up above the gap; the transition temperature is correlated with the size of the spin gap. Depending on the magnitude of the spin gap with respect to the magnetic spectrum, the enhanced magnetic scattering at low temperature can be either commensurate or incommensurate. Connections between stripe correlations and superconductivity are discussed.

  7. Free-standing oxide superconducting articles

    DOE Patents [OSTI]

    Wu, Xin D. (Greenbelt, MD); Muenchausen, Ross E. (Espanola, NM)

    1993-01-01

    A substrate-free, free-standing epitaxially oriented superconductive film including a layer of a template material and a layer of a ceramic superconducting material is provided together with a method of making such a substrate-free ceramic superconductive film by coating an etchable material with a template layer, coating the template layer with a layer of a ceramic superconductive material, coating the layer of ceramic superconductive material with a protective material, removing the etchable material by an appropriate means so that the etchable material is separated from a composite structure including the template lay This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).

  8. Fermionic Models with Superconducting Circuits

    E-Print Network [OSTI]

    U. Las Heras; L. García-Álvarez; A. Mezzacapo; E. Solano; L. Lamata

    2015-03-31

    We propose a method for the efficient quantum simulation of fermionic systems with superconducting circuits. It consists in the suitable use of Jordan-Wigner mapping, Trotter decomposition, and multiqubit gates, be with the use of a quantum bus or direct capacitive couplings. We apply our method to the paradigmatic cases of 1D and 2D Fermi-Hubbard models, involving couplings with nearest and next-nearest neighbours. Furthermore, we propose an optimal architecture for this model and discuss the benchmarking of the simulations in realistic circuit quantum electrodynamics setups.

  9. Quantum trajectories of superconducting qubits

    E-Print Network [OSTI]

    S. J. Weber; K. W. Murch; M. E. Schwartz; N. Roch; I. Siddiqi

    2015-06-26

    In this review, we discuss recent experiments that investigate how the quantum sate of a superconducting qubit evolves during measurement. We provide a pedagogical overview of the measurement process, when the qubit is dispersively coupled to a microwave frequency cavity, and the qubit state is encoded in the phase of a microwave tone that probes the cavity. A continuous measurement record is used to reconstruct the individual quantum trajectories of the qubit state, and quantum state tomography is performed to verify that the state has been tracked accurately. Furthermore, we discuss ensembles of trajectories, time-symmetric evolution, two-qubit trajectories, and potential applications in measurement-based quantum error correction.

  10. Radio bursts from superconducting strings

    E-Print Network [OSTI]

    Yi-Fu Cai; Eray Sabancilar; Tanmay Vachaspati

    2012-01-30

    We show that radio bursts from cusps on superconducting strings are linearly polarized, thus, providing a signature that can be used to distinguish them from astrophysical sources. We write the event rate of string-generated radio transients in terms of observational variables, namely, the event duration and flux. Assuming a canonical set of observational parameters, we find that the burst event rate can be quite reasonable, e.g., order ten a year for Grand Unified strings with 100 TeV currents, and a lack of observed radio bursts can potentially place strong constraints on particle physics models.

  11. Afterpulsing and Instability in Superconducting Nanowire Avalanche Photodetectors

    E-Print Network [OSTI]

    F. Marsili; F. Najafi; E. Dauler; R. J. Molnar; K. K. Berggren

    2012-03-01

    We investigated the reset time of superconducting nanowire avalanche photodetectors (SNAPs) based on 30 nm wide nanowires. We studied the dependence of the reset time of SNAPs on the device inductance and discovered that SNAPs can provide a speed-up relative to SNSPDs with the same area, but with some limitations: (1) reducing the series inductance of SNAPs (necessary for the avalanche formation) could result in the detectors operating in an unstable regime; (2) a trade-off exists between maximizing the bias current margin and minimizing the reset time of SNAPs; and (3) reducing the reset time of SNAPs below ~ 1 ns resulted in afterpulsing.

  12. The Theory of Super-conductivity in the

    E-Print Network [OSTI]

    Landweber, Laura

    of high-Tc superconductivity in the cuprates. (Cuprates are ceramic materials that superconduct at temperatures much higher than should be possible according to conventional the- ory.) Superconductivity the development of a theory of high-temperature superconductivity. Since there is as yet no complete theory

  13. Superconductivity and Quantum Oscillations in Crystalline Bi Nanowire

    E-Print Network [OSTI]

    inner core and the surface oxide layer. Under a perpendicular H, the resistance in the superconducting

  14. Superconducting coil and method of stress management in a superconducting coil

    DOE Patents [OSTI]

    McIntyre, Peter M. (College Station, TX); Shen, Weijun (Oak Ridge, TN); Diaczenko, Nick (College Station, TX); Gross, Dan A. (College Station, TX)

    1999-01-01

    A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

  15. High Temperature Superconducting Underground Cable

    SciTech Connect (OSTI)

    Farrell, Roger, A.

    2010-02-28

    The purpose of this Project was to design, build, install and demonstrate the technical feasibility of an underground high temperature superconducting (HTS) power cable installed between two utility substations. In the first phase two HTS cables, 320 m and 30 m in length, were constructed using 1st generation BSCCO wire. The two 34.5 kV, 800 Arms, 48 MVA sections were connected together using a superconducting joint in an underground vault. In the second phase the 30 m BSCCO cable was replaced by one constructed with 2nd generation YBCO wire. 2nd generation wire is needed for commercialization because of inherent cost and performance benefits. Primary objectives of the Project were to build and operate an HTS cable system which demonstrates significant progress towards commercial progress and addresses real world utility concerns such as installation, maintenance, reliability and compatibility with the existing grid. Four key technical areas addressed were the HTS cable and terminations (where the cable connects to the grid), cryogenic refrigeration system, underground cable-to-cable joint (needed for replacement of cable sections) and cost-effective 2nd generation HTS wire. This was the world’s first installation and operation of an HTS cable underground, between two utility substations as well as the first to demonstrate a cable-to-cable joint, remote monitoring system and 2nd generation HTS.

  16. The Hardest Superconducting Metal Nitride

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

    Wang, Shanmin; Antonio, Daniel; Yu, Xiaohui; Zhang, Jianzhong; Cornelius, Andrew L.; He, Duanwei; Zhao, Yusheng

    2015-09-03

    Transition–metal (TM) nitrides are a class of compounds with a wide range of properties and applications. Hard superconducting nitrides are of particular interest for electronic applications under working conditions such as coating and high stress (e.g., electromechanical systems). However, most of the known TM nitrides crystallize in the rock–salt structure, a structure that is unfavorable to resist shear strain, and they exhibit relatively low indentation hardness, typically in the range of 10–20?GPa. Here, we report high–pressure synthesis of hexagonal ?–MoN and cubic ?–MoN through an ion–exchange reaction at 3.5?GPa. The final products are in the bulk form with crystallite sizesmore »of 50 – 80??m. Based on indentation testing on single crystals, hexagonal ?–MoN exhibits excellent hardness of ~30?GPa, which is 30% higher than cubic ?–MoN (~23?GPa) and is so far the hardest among the known metal nitrides. The hardness enhancement in hexagonal phase is attributed to extended covalently bonded Mo–N network than that in cubic phase. The measured superconducting transition temperatures for ?–MoN and cubic ?–MoN are 13.8 and 5.5?K, respectively, in good agreement with previous measurements.« less

  17. The Hardest Superconducting Metal Nitride

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

    Wang, Shanmin; Antonio, Daniel; Yu, Xiaohui; Zhang, Jianzhong; Cornelius, Andrew L.; He, Duanwei; Zhao, Yusheng

    2015-09-03

    Transition–metal (TM) nitrides are a class of compounds with a wide range of properties and applications. Hard superconducting nitrides are of particular interest for electronic applications under working conditions such as coating and high stress (e.g., electromechanical systems). However, most of the known TM nitrides crystallize in the rock–salt structure, a structure that is unfavorable to resist shear strain, and they exhibit relatively low indentation hardness, typically in the range of 10–20 GPa. Here, we report high–pressure synthesis of hexagonal ?–MoN and cubic ?–MoN through an ion–exchange reaction at 3.5 GPa. The final products are in the bulk form withmore »crystallite sizes of 50 – 80 ?m. Based on indentation testing on single crystals, hexagonal ?–MoN exhibits excellent hardness of ~30 GPa, which is 30% higher than cubic ?–MoN (~23 GPa) and is so far the hardest among the known metal nitrides. The hardness enhancement in hexagonal phase is attributed to extended covalently bonded Mo–N network than that in cubic phase. The measured superconducting transition temperatures for ?–MoN and cubic ?–MoN are 13.8 and 5.5 K, respectively, in good agreement with previous measurements.« less

  18. Magnetohydrodynamics in Superconducting-Superfluid Neutron Stars

    E-Print Network [OSTI]

    Gregory Mendell

    1997-09-09

    MHD equations are presented for the mixture of superfluid neutrons, superconducting protons, and normal electrons believed to exist in the outer cores of neutron stars. The dissipative effects of electron viscosity and mutual friction due to electron-vortex scattering are also included. It is shown that Alfven waves are replaced by cyclotron- vortex waves that have not been previously derived from MHD theory. The cyclotron- vortex waves are analogous to Alfven waves with the tension due to the magnetic energy density replaced by the vortex energy density. The equations are then put into a simplified form useful for studying the effects of the interior magnetic field on the dynamics. Of particular interest is the crust-core coupling time which can be inferred from pulsar glitch observations. The hypothesis that cyclotron-vortex waves play a significant role in the core spin-up during a glitch is used to place limits on the interior magnetic field. The results are compared with those of other studies.

  19. Progress on the Modeling and Modification of the MICE Superconducting Spectrometer Solenoids

    E-Print Network [OSTI]

    Virostek, S.P.

    2013-01-01

    IEEE Transactions on Applied Superconductivity 15, No. 2, p.E E Transactions on Applied Superconductivity 15, No. 2, p.and Modeling of the MICE Superconducting Spectrometer

  20. Superconducting magnets for induction linac phase-rotation in a neutrino factory

    E-Print Network [OSTI]

    Green, M.A.; Yu, S.

    2001-01-01

    et al, "The Role of Superconductivity and Cryogenics in theTransactions on Applied Superconductivity 11, p 2180, (2001)hydrogen absorbers. The superconducting solenoid quench

  1. Frequency-Domain Multiplexed Readout for Superconducting Gamma-Ray Detectors

    E-Print Network [OSTI]

    Dreyer, Jonathan G.

    2008-01-01

    sensor arrays with a superconducting quantum interferenceMultiplexed Readout for Superconducting Gamma-Ray Detectorsdetectors based on superconducting transition edge sensors (

  2. Update on the Modification and Testing of the MICE Superconducting Spectrometer Solenoids

    E-Print Network [OSTI]

    Virostek, S.P.

    2013-01-01

    IEEE Transactions on Applied Superconductivity 15, No. 2, p.IEEE Transactions on Applied Superconductivity 15, No. 2, p.TESTING OF THE MICE SUPERCONDUCTING SPECTROMETER SOLENOIDS*

  3. QUENCH PROTECTION AND DESIGN OF LARGE HIGH CURRENT DENSITY SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    failure in the TPC superconducting magnet," Proceedings ofstrain on epoxy-impregnated superconducting composties," inQuench protection for superconduct­ ing magnets with a

  4. Fabrication of a Short-Period Nb3Sn Superconducting Undulator

    E-Print Network [OSTI]

    Dietderich, Daniel

    2008-01-01

    Trans. on Applied Superconductivity, Vol. 13, No. 2, pp.Trans. on Applied Superconductivity, MT-19, June 2005. [7]Trans. on Applied Superconductivity, vol. 15, no. 2, 2005,

  5. A LARGE HIGH CURRENT DENSITY SUPERCONDUCTING SOLENOID FOR THE TIME PROJECTION CHAMBER EXPERIMENT

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01

    TPC magnet integrates the superconduct- ing coil, the quenchto 1978 Applied Superconductivity Conference in Pittsburgh,HIGH CURRENT DENSITY SUPERCONDUCTING SOLENOID FOR THE TIME

  6. A Superconducting Bending Magnet System for a Compact Synchrotron Light Source

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01

    Garren, "Optimization of Superconducting Bending Magnets foral, "Development of a Superconducting Compact Storage Ringsdesigns M. A Green, "Superconducting Dipole Magnets for

  7. Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization

    E-Print Network [OSTI]

    Myers, Michael James

    2010-01-01

    4.3.2 Superconducting microstrip simulations 4.4 Impedance4.3 Superconducting microstrip . . . . . . . . . . 4.3.1Principles of superconductive devices and circuits, (second

  8. A SUPERCONDUCTING MAGNET SYSTEM FOR THE SPIRIT COSMIC RAY SPACE TELESCOPE

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    secondary circuit*® NbVSh superconducting coils ElectricalAugust 21-24, 1979 A SUPERCONDUCTING MAGNET SYSTEM FOR THETELESCOPE MASTER A SUPERCONDUCTING MAGNET SYSTEM FOR THE

  9. Photoacoustic signal saturation and optical limiting in C70-toluene solution

    E-Print Network [OSTI]

    Harilal, S. S.

    -harmonic generation12 and optical limiting13,14 and self-defocusing of laser beams due to high values of third have unique properties such as relatively high temperature superconductivity,7 photovoltaic response,8

  10. Status of superconducting magnets for the Superconducting Super Collider

    SciTech Connect (OSTI)

    Schermer, R.I.

    1993-09-01

    The arc sections of the High Energy Booster and the two Collider Rings will need more than 10,000, very large, superconducting dipole and quadrupole magnets. Development work on these magnets was carried out at US/DOE laboratories in a program that began in the mid 1980`s. In 1991-1992, the technology was transferred to industry and twenty, full-length, Collider dipoles were successfully fabricated and tested. This program, along with HERA and Tevatron experience, has provided industry a data base to use in formulating detailed designs for the prototypes of the accelerator magnets, with an eye to reducing cost and enhancing producibility. Several model magnets from this latest phase of the industrial program have already been tested. The excessive ramp-rate sensitivity of the magnets is understood and solutions are under investigation.

  11. Nb-Pb superconducting RF gun

    SciTech Connect (OSTI)

    J. Sekutowicz; J. Iversen; G. Kreps; W.D. Moller; W. Singer; X. Singer; I. Ben-Zvi; A. Burrill; J. Smedley; T. Rao; M. Ferrario; P. Kneisel; J. Langner; P. Strzyzewski; R. Lefferts; A. Lipski; K. Szalowski; K. Ko; L. Xiao

    2006-04-14

    We report on the status of an electron RF-gun made of two superconductors: niobium and lead. The presented design combines the advantages of the RF performance of bulk niobium superconducting cavities and the reasonably high quantum efficiency of lead, as compared to other superconducting metals. The concept, mentioned in a previous paper, follows the attractive approach of all niobium superconducting RF-gun as it has been proposed by the BNL group. Measured values of quantum efficiency for lead at various photon energies, analysis of recombination time of photon-broken Cooper pairs for lead and niobium, and preliminary cold test results are discussed in this paper.

  12. Basic Research Needs for Superconductivity. Report of the Basic Energy Sciences Workshop on Superconductivity, May 8-11, 2006

    SciTech Connect (OSTI)

    Sarrao, J.; Kwok, W-K; Bozovic, I.; Mazin, I.; Seamus, J. C.; Civale, L.; Christen, D.; Horwitz, J.; Kellogg, G.; Finnemore, D.; Crabtree, G.; Welp, U.; Ashton, C.; Herndon, B.; Shapard, L.; Nault, R. M.

    2006-05-11

    As an energy carrier, electricity has no rival with regard to its environmental cleanliness, flexibility in interfacing with multiple production sources and end uses, and efficiency of delivery. In fact, the electric power grid was named ?the greatest engineering achievement of the 20th century? by the National Academy of Engineering. This grid, a technological marvel ingeniously knitted together from local networks growing out from cities and rural centers, may be the biggest and most complex artificial system ever built. However, the growing demand for electricity will soon challenge the grid beyond its capability, compromising its reliability through voltage fluctuations that crash digital electronics, brownouts that disable industrial processes and harm electrical equipment, and power failures like the North American blackout in 2003 and subsequent blackouts in London, Scandinavia, and Italy in the same year. The North American blackout affected 50 million people and caused approximately $6 billion in economic damage over the four days of its duration. Superconductivity offers powerful new opportunities for restoring the reliability of the power grid and increasing its capacity and efficiency. Superconductors are capable of carrying current without loss, making the parts of the grid they replace dramatically more efficient. Superconducting wires carry up to five times the current carried by copper wires that have the same cross section, thereby providing ample capacity for future expansion while requiring no increase in the number of overhead access lines or underground conduits. Their use is especially attractive in urban areas, where replacing copper with superconductors in power-saturated underground conduits avoids expensive new underground construction. Superconducting transformers cut the volume, weight, and losses of conventional transformers by a factor of two and do not require the contaminating and flammable transformer oils that violate urban safety codes. Unlike traditional grid technology, superconducting fault current limiters are smart. They increase their resistance abruptly in response to overcurrents from faults in the system, thus limiting the overcurrents and protecting the grid from damage. They react fast in both triggering and automatically resetting after the overload is cleared, providing a new, self-healing feature that enhances grid reliability. Superconducting reactive power regulators further enhance reliability by instantaneously adjusting reactive power for maximum efficiency and stability in a compact and economic package that is easily sited in urban grids. Not only do superconducting motors and generators cut losses, weight, and volume by a factor of two, but they are also much more tolerant of voltage sag, frequency instabilities, and reactive power fluctuations than their conventional counterparts. The challenge facing the electricity grid to provide abundant, reliable power will soon grow to crisis proportions. Continuing urbanization remains the dominant historic demographic trend in the United States and in the world. By 2030, nearly 90% of the U.S. population will reside in cities and suburbs, where increasingly strict permitting requirements preclude bringing in additional overhead access lines, underground cables are saturated, and growth in power demand is highest. The power grid has never faced a challenge so great or so critical to our future productivity, economic growth, and quality of life. Incremental advances in existing grid technology are not capable of solving the urban power bottleneck. Revolutionary new solutions are needed ? the kind that come only from superconductivity.

  13. Gapless superconductivity and string theory

    E-Print Network [OSTI]

    Sergei Khlebnikov

    2014-11-06

    Coexistence of superconducting and normal components in nanowires at currents below the critical (a "mixed" state) would have important consequences for the nature and range of potential applications of these systems. For clean samples, it represents a genuine interaction effect, not seen in the mean-field theory. Here we consider properties of such a state in the gravity dual of a strongly coupled superconductor constructed from D3 and D5 branes. We find numerically uniform gapless solutions containing both components but argue that they are unstable against phase separation, as their free energies are not convex. We speculate on the possible nature of the resulting non-uniform sate ("emulsion") and draw analogies between that state and the familiar mixed state of a type II superconductor in a magnetic field.

  14. Subranging technique using superconducting technology

    DOE Patents [OSTI]

    Gupta, Deepnarayan (Hawthorne, NY)

    2003-01-01

    Subranging techniques using "digital SQUIDs" are used to design systems with large dynamic range, high resolution and large bandwidth. Analog-to-digital converters (ADCs) embodying the invention include a first SQUID based "coarse" resolution circuit and a second SQUID based "fine" resolution circuit to convert an analog input signal into "coarse" and "fine" digital signals for subsequent processing. In one embodiment, an ADC includes circuitry for supplying an analog input signal to an input coil having at least a first inductive section and a second inductive section. A first superconducting quantum interference device (SQUID) is coupled to the first inductive section and a second SQUID is coupled to the second inductive section. The first SQUID is designed to produce "coarse" (large amplitude, low resolution) output signals and the second SQUID is designed to produce "fine" (low amplitude, high resolution) output signals in response to the analog input signals.

  15. Magnetic fluctuations and heavy electron superconductivity

    SciTech Connect (OSTI)

    Norman, M.R.

    1988-01-01

    A magnetic fluctuation self-energy based on neutron scattering data is used to calculate mass renormalizations, and superconducting critical temperatures and order parameters, for various heavy electron metals.

  16. Nonlinear high-temperature superconducting terahertz metamaterials

    E-Print Network [OSTI]

    Grady, Nathaniel K.

    We report the observation of a nonlinear terahertz response of split-ring resonator arrays made of high-temperature superconducting films. Intensity-dependent transmission measurements indicate that the resonance strength ...

  17. Bipolaron Model of Superconductivity in Chalcogenide Glasses

    E-Print Network [OSTI]

    Liang-You Zheng; Bo-Cheng Wang; Shan T. Lai

    2010-10-25

    In this paper we propose a small bipolaron model for the superconductivity in the Chalcogenide glasses (c-As2Te3 and c-GeTe). The results are agree with the experiments.

  18. Cooling arrangement for a superconducting coil

    DOE Patents [OSTI]

    Herd, K.G.; Laskaris, E.T.

    1998-06-30

    A superconducting device is disclosed, such as a superconducting rotor for a generator or motor. A vacuum enclosure has an interior wall surrounding a cavity containing a vacuum. A superconductive coil is placed in the cavity. A generally-annularly-arranged, thermally-conductive sheet has an inward-facing surface contacting generally the entire outward-facing surface of the superconductive coil. A generally-annularly-arranged coolant tube contains a cryogenic fluid and contacts a generally-circumferential portion of the outward-facing surface of the sheet. A generally-annularly-arranged, thermally-insulative coil overwrap generally circumferentially surrounds the sheet. The coolant tube and the inward-facing surface of the coil overwrap together contact generally the entire outward-facing surface of the sheet. 3 figs.

  19. Energy Programs | Center for Emergent Superconductivity

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

    Jin, R., Sales, B.C., Mandrus, D., Gillett, J., Sebastian, S.E., and Greene, L.H., Superconduct. Sci. Technol. 23, 054009-1-7 (2010). C-axis critical current density of...

  20. Towards a next theory of superconductivity

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

    Communications Office (505) 667-0471 Email "High magnetic-field measurements of doped copper-oxide superconductors are paving the way to a new theory of superconductivity," said...

  1. Cellulose-Bound Magnesium Diboride Superconductivity

    E-Print Network [OSTI]

    Ryan, Dominic

    Cellulose-Bound Magnesium Diboride Superconductivity Y.L. Lin and M.O. Pekguleryuz Department a cellulose based polymer. Cellulose tends to react only very weekly and is very robust, hence constitutes

  2. New Advances in SuperConducting Materials

    ScienceCinema (OSTI)

    None

    2014-08-12

    Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laboratory, new materials science concepts are bringing this essential technology closer to widespread industrial use.

  3. Superconductivity with Stripes | Advanced Photon Source

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

    structure in high-Tc superconductors was manipulated in high-pressure experiments at the APS. The physics of low-temperature superconductivity is fairly well understood, but the...

  4. Operational experience with superconducting synchrotron magnets

    SciTech Connect (OSTI)

    Martin, P.S.

    1987-03-01

    The operational experience with the Fermilab Tevatron is presented, with emphasis on reliability and failure modes. Comprisons are made between the operating efficiencies for the superconducting machine and for he conventional Main Ring.

  5. Strongly correlated electron behavior : superconductivity and non-Fermi liquid behavior in Ce?-xRxColn?

    E-Print Network [OSTI]

    Gonzales, Eileen

    2009-01-01

    C. Superconductivity . . . . . . . . . . . . . . . . . . .1. Heavy Fermion Superconductivity . . . . . . .of a type I and type II superconductor showing magnetization

  6. Armored spring-core superconducting cable and method of construction

    DOE Patents [OSTI]

    McIntyre, Peter M. (611 Montclair, College Station, TX 77840); Soika, Rainer H. (1 Hensel, #X4C, College Station, TX 77840)

    2002-01-01

    An armored spring-core superconducting cable (12) is provided. The armored spring-core superconducting cable (12) may include a spring-core (20), at least one superconducting strand (24) wound onto the spring-core (20), and an armored shell (22) that encases the superconducting strands (24). The spring-core (20) is generally a perforated tube that allows purge gases and cryogenic liquids to be circulated through the armored superconducting cable (12), as well as managing the internal stresses within the armored spring-core superconducting cable (12). The armored shell (22) manages the external stresses of the armored spring-core superconducting cable (12) to protect the fragile superconducting strands (24). The armored spring-core superconducting cable (12) may also include a conductive jacket (34) formed outwardly of the armored shell (22).

  7. Architecture for high critical current superconducting tapes

    DOE Patents [OSTI]

    Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

    2002-01-01

    Improvements in critical current capacity for superconducting film structures are disclosed and include the use of, e.g., multilayer YBCO structures where individual YBCO layers are separated by a layer of an insulating material such as CeO.sub.2 and the like, a layer of a conducting material such as strontium ruthenium oxide and the like or by a second superconducting material such as SmBCO and the like.

  8. Casimir energy and the superconducting phase transition

    E-Print Network [OSTI]

    Giuseppe Bimonte; Enrico Calloni; Giampiero Esposito; Luigi Rosa

    2006-01-24

    We study the influence of Casimir energy on the critical field of a superconducting film, and we show that by this means it might be possible to directly measure, for the first time, the variation of Casimir energy that accompanies the superconducting transition. It is shown that this novel approach may also help clarifying the long-standing controversy on the contribution of TE zero modes to the Casimir energy in real materials.

  9. Entangling two superconducting LC coherent modes via a superconducting flux qubit

    E-Print Network [OSTI]

    Mei-Yu Chen; Matisse W. Y. Tu; Wei-Min Zhang

    2009-11-10

    Based on a pure solid-state device consisting of two superconducting LC circuits coupled to a superconducting flux qubit, we propose in this paper that the maximally entangled coherent states of the two LC modes can be generated for arbitrary coherent states through flux qubit controls.

  10. 2003 Annual Superconductivity2003 Annual Superconductivity Peer ReviewPeer Review

    E-Print Network [OSTI]

    ;Superconductivity Program at NREL for Electric SystemsSuperconductivity Program at NREL for Electric Systems Non NREL Team Members:NREL Team Members: RaghuRaghu BhattacharyaBhattacharya (Team Leader) Jun ChenJun Chen Cooperative Programs are funded by NREL. 03458202 #12;Program Objectives/Relevance (FY 2003)Program Objectives

  11. Fluctuations in systemsFluctuations in systems with superconducting islandswith superconducting islands

    E-Print Network [OSTI]

    Fominov, Yakov

    Fluctuations in systemsFluctuations in systems with superconducting islandswith superconducting islands Mikhail A. Skvortsov Mikhail V. Feigel'man Anatoly I. Larkin Landau Institute, Moscow #12;OutlineOutline #12;Uniform materials, grains, islandsUniform materials, grains, islands #12;Two mechanism of

  12. Anisotropic transport properties of ferromagnetic-superconducting bilayers 

    E-Print Network [OSTI]

    Kayali, MA; Pokrovsky, Valery L.

    2004-01-01

    We study the transport properties of vortex matter in a superconducting thin film separated by a thin insulator layer from a ferromagnetic layer. We assume an alternating stripe structure for both FM and superconducting (SC) layers as found in S...

  13. Supplementary Information for Simulating weak localization in superconducting quantum circuit

    E-Print Network [OSTI]

    Martinis, John M.

    Supplementary Information for Simulating weak localization in superconducting quantum circuit Yu-type entangled state in superconducting quantum circuits.[2, 3] We rst generated a photon in the readout qubit

  14. Superconducting magnets for muon capture and phase rotation

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01

    of Various Cases for Superconducti ng Magnets Inside andTransactions on Applied Superconductivity 7, No 2. P 642 (LBNL-43998 SC-MAG-683 SUPERCONDUCTING MAGNETS FOR MUON

  15. Control of Superconductivity in Cuprate/Manganite Heterostructures

    E-Print Network [OSTI]

    Pang, Brian SiewHan

    deposited, which exhibited superconducting and magnetic properties to minimum thicknesses of 3nm for both YBCO and LSMO. Using spin injection, via a ferromagnet, to create a spin imbalance in the superconductor, a suppression of superconducting critical...

  16. Friedel-Like Oscillations from Interstitial Iron in Superconducting...

    Office of Scientific and Technical Information (OSTI)

    Interstitial Iron in Superconducting Fe1+yTe0.62Se0.38 Using polarized and unpolarized neutron scattering we show that interstitial Fe in superconducting Fe1+yTe1-xSex...

  17. Optimization of superconducting magnetic bearings using finite element modeling

    E-Print Network [OSTI]

    Bryslawskyj, Jason (Jason Bogdan)

    2009-01-01

    This project investigated the possibility of using superconducting bearings in large (3 - 100 MW) electric drives. Superconducting bearings are used to levitate the rotors inside electric drives via the Meiissner effect, ...

  18. High Temperature Superconductivity in Cuprates: a model

    E-Print Network [OSTI]

    P. R. Silva

    2010-07-16

    A model is proposed such that quasi-particles (electrons or holes) residing in the CuO2 planes of cuprates may interact leading to metallic or superconducting behaviors. The metallic phase is obtained when the quasi-particles are treated as having classical kinetic energies and the superconducting phase occurs when the quasi-particles are taken as extremely relativistic objects. The interaction between both kinds of particles is provided by a force dependent-on-velocity. In the case of the superconducting behavior, the motion of apical oxygen ions provides the glue to establish the Cooper pair. The model furnishes explicit relations for the Fermi velocity, the perpendicular and the in-plane coherence lengths, the zero-temperature energy gap, the critical current density, the critical parallel and perpendicular magnetic fields. All these mentioned quantities are expressed in terms of fundamental physical constants as: charge and mass of the electron, light velocity in vacuum, Planck constant, electric permittivity of the vacuum. Numerical evaluation of these quantities show that their values are close those found for the superconducting YBaCuO, leading to think the model as being a possible scenario to explain superconductivity in cuprates.

  19. Superconductivity at Dawn of the Iron Age

    ScienceCinema (OSTI)

    Tesanovic, Zlatko [Johns Hopkins University, Baltimore, Maryland, United States

    2010-09-01

    Superconductivity is a stunning quantum phenomenon and among the deepest paradigms in all of physics. From fundamental theories of the universe to strange goings-on in exotic materials to medical imaging and cell phones, its conceptual and practical dimensions span a reach as wide as anything in science. Twenty-odd years ago, the discovery of copper oxides ushered in a new era of high-temperature superconductivity, and the joyous exuberance that followed - with physicists throwing everything from fancy gauge theories to synchrotron radiation into its kitchen sink - only recently began to show any signs of waning. In the spring of 2008, as if on cue, a new family of iron pnictide high-temperature superconductors burst on the scene, hinting at an alternative route to room-temperature superconductivity and all of its momentous consequences. Fueled by genuine excitement - and a bit of hype - the iron-based superconductivity turned into a science blockbuster of 2009. I will present a pedagogical review of this new field, contrast the physics of iron- and copper-based systems, and speculate on the microscopic origins of the two types of high-temperature superconductivity.

  20. Color superconductivity and dense quark matter

    E-Print Network [OSTI]

    Massimo Mannarelli

    2008-12-26

    The properties of cold and dense quark matter have been the subject of extensive investigation, especially in the last decade. Unfortunately, we still lack of a complete understanding of the properties of matter in these conditions. One possibility is that quark matter is in a color superconducting phase which is characterized by the formation of a diquark condensate. We review some of the basic concepts of color superconductivity and some of the aspects of this phase of matter which are relevant for compact stars. Since quarks have color, flavor as well as spin degrees of freedom many different color superconducting phases can be realized. At asymptotic densities QCD predicts that the color flavor locked phase is favored. At lower densities where the QCD coupling constant is large, perturbative methods cannot be applied and one has to rely on some effective model, eventually trying to constrain such a model with experimental observations. The picture is complicated by the requirement that matter in the interior of compact stars is in weak equilibrium and neutral. These conditions and the (possible) large value of the strange quark mass conspire to separate the Fermi momenta of quarks with different flavors, rendering homogenous superconducting phases unstable. One of the aims of this presentation is to introduce non-experts in the field to some of the basic ideas of color superconductivity and to some of its open problems.

  1. PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*)

    E-Print Network [OSTI]

    Boyer, Edmond

    L-435 PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*) F. MEUNIER and P of Si and Ge in Al thin films at 8 K produces alloys exhibiting enhanced superconducting transition in the superconducting transition temperature Tc of several such alloys [2], [5], [6] : Josephson tunnelling

  2. Superconducting Wires Enabled by Nanodots wins Nano50TM Award

    E-Print Network [OSTI]

    includes nanoscale columns of non-superconducting material embedded within the superconductorSuperconducting Wires Enabled by Nanodots wins Nano50TM Award HTS Wires Enabled via 3D Self-Assembly of Insulating Nanodots Background · For most large-scale applications of high-temperature superconducting (HTS

  3. Fluctuations from edge defects in superconducting resonators A. Megrant,1

    E-Print Network [OSTI]

    Martinis, John M.

    Fluctuations from edge defects in superconducting resonators C. Neill,1 A. Megrant,1 R. Barends,1 August 2013) Superconducting resonators, used in astronomy and quantum computation, couple strongly to microscopic two-level defects. We monitor the microwave response of superconducting resonators and observe

  4. Field Test of the Superconducting Gravimeter as a Hydrologic Sensor

    E-Print Network [OSTI]

    Scanlon, Bridget R.

    Field Test of the Superconducting Gravimeter as a Hydrologic Sensor by Clark R. Wilson1 , Bridget of a transportable version of a superconducting gravimeter (SG) intended for groundwater storage monitoring. The test of a transportable superconducting gravimeter (SG) designed to monitor sur- face gravity and provide a direct measure

  5. Strong Coupling of a Spin Ensemble to a Superconducting Resonator

    E-Print Network [OSTI]

    Vallette, Bruno

    Strong Coupling of a Spin Ensemble to a Superconducting Resonator: Towards Superconducting Hybrid Quantum Circuits Yui KUBO, Cecile Greze, Florian R. Ong, Patrice Bertet). Superconducting qubit #12;Yui KUBO GDR-IQFA, Nice, 24 Mar 2011 Y. Nakamura et al., Nature

  6. Emulation of a Quantum Spin with a Superconducting Phase Qudit

    E-Print Network [OSTI]

    Martinis, John M.

    Emulation of a Quantum Spin with a Superconducting Phase Qudit Matthew Neeley,1 M. Ansmann,1 computing tasks. We demonstrate the operation of a superconducting phase qudit with d = 5, showing how, making a qudit emulator potentially more efficient. We demonstrate the operation of a superconducting

  7. Quantum Logic Gates in Superconducting Qubits John M. Martinis

    E-Print Network [OSTI]

    Martinis, John M.

    Quantum Logic Gates in Superconducting Qubits John M. Martinis Department of Physics University on surface codes may allow errors in the 10-2 range [2]. Much research in superconducting qubits has been di for superconducting qubits, since they typically use fixed coupling elements set by fabrication. TRANSITION LOGIC

  8. Singlet oxygen luminescence detection with a fibre-coupled superconducting

    E-Print Network [OSTI]

    Greenaway, Alan

    Singlet oxygen luminescence detection with a fibre-coupled superconducting nanowire single luminescence detection Fibre-based singlet oxygen luminescence detection References Superconducting Detector, is an intermediate in many biological processes. We employ a superconducting nanowire single-photon detector (SNSPD

  9. Sr2IrO4: Gateway to cuprate superconductivity?

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

    Mitchell, J. F.

    2015-06-05

    High temperature superconductivity in cuprates remains a defining challenge in condensed matter physics. Recently, a new set of related compounds based on Ir rather than Cu has been discovered that may be on the verge of superconductivity themselves or be able to shed new light on the underlying interactions responsible for superconductivity in the cuprates.

  10. Study on the energy criterion of cuprate superconductivity

    E-Print Network [OSTI]

    Gu Jiapu

    2010-02-09

    In this paper, we use the variation of spontaneous magnetization to describe the influence of electron holes in cuprate superconductors, and use competitive energy relations to explore the superconductivity rule and energy criterion, on this basis, we can deduce a clear physical image of superconducting phase diagram and superconducting mechanism.

  11. Impurity effects in superconducting UPt sub 3

    SciTech Connect (OSTI)

    Aronson, M.C. (The Harrison M. Randall Laboratory of Physics, The University of Michigan, Ann Arbor, Michigan 48109 (USA)); Vorenkamp, T.; Koziol, Z.; de Visser, A.; Bakker, K.; Franse, J.J.M. (Natuurkundig Laboratorium der Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands (USA)); Smith, J.L. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (USA))

    1991-04-15

    Superconducting UPt{sub 3} is characterized by a novel and complex magnetic field-temperature phase diagram, with two superconducting transitions at {ital T}{sub {ital c}1} and {ital T}{sub {ital c}2} in zero field. We have studied the effects of Pd and Y impurities on the zero field superconducting properties of UPt{sub 3}. Resistance measurements show that both dopants increase the residual resistivity and decrease the spin fluctuation temperature in the normal state. {ital T}{sub {ital c}1} is depressed by both dopants, but more effectively by Pd. {vert bar}{ital T}{sub {ital c}1} {minus} {ital T}{sub {ital c}2}{vert bar} is essentially unaffected by Y doping, but increases dramatically with Pd doping.

  12. Superconducting magnetic shielding apparatus and method

    DOE Patents [OSTI]

    Clem, John R. (Ames, IA); Clem, John R. (Ames, IA)

    1983-01-01

    Disclosed is a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped.

  13. Superconducting magnetic shielding apparatus and method

    DOE Patents [OSTI]

    Clem, J.R.

    1982-07-09

    Disclosed is a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped.

  14. Superconducting magnetic shielding apparatus and method

    DOE Patents [OSTI]

    Clem, J.R.; Clem, J.R.

    1983-10-11

    Disclosed are a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped. 5 figs.

  15. Health and safety guide for inorganic compounds and metals used in the fabrication of superconductive alloys

    SciTech Connect (OSTI)

    Arnold, S.D.; Talley, G.M.

    1990-04-25

    This health and safety guide was written to satisfy two objectives: to summarize the toxicity of metals and alloys used in superconductivity for the benefit of those who work with these materials, and to summarize and describes the basic principles of a highly technical field from a health and safety point-of-view for the benefit of health professionals. The guide begins with a profile of the superconductivity industry, including a list of current and potential applications, a literature review of the market potential, and summary of the current industry status. The body of the paper provides a toxicity and hazard summary for 50 metals, alloys and metal oxides used in superconductivity. The toxicity and hazard summary for all 50 compounds includes: occupational exposure limits, explosiveness and flammability potential, LD{sub 50}'s, chemical and physical properties, incompatibilities and reactivities, recommended personal protective equipment, symptoms of acute and chronic exposure, target organs and toxic effects, and steps for emergency first aid. Finally, a discussion of general occupational hygiene principles is provided, with emphasis on how these principles apply to the unique field of superconductivity. 41 refs.

  16. Discovery of plutonium-based superconductivity

    SciTech Connect (OSTI)

    Sarrao, John L.,; Thompson, J. D. (Joe David); Moreno, N. O.; Morales, L. A. (Luis A.); Wastin, F. (Franck); Rebizant, J.; Boulet, P.; Colineau, E.; Lander, G. H.

    2002-01-01

    The discovery of superconductivity in single crystals of PuCoGa{sub 5} with transition temperature T{sub c}=18.5 K is discussed. The existing data lead to the speculation that the superconductivity in PuCoGa{sub 5} may be unconventional. In such a scenario the properties of PuCoGa{sub 5} would be intermediate between those of isostructural UCoGa{sub 5} and CeCoIn{sub 5}, more heavily studied f-electron materials.

  17. Criterion of stability of the superconducting state

    E-Print Network [OSTI]

    Iogann Tolbatov

    2009-10-23

    In this paper, we propose to draw attention to the stability criterion of the superconductor current state. We use for this purpose the rough systems mathematical apparatus allowing us to relate the desired criterion with the dielectric permittivity of the matter and to identify the type of all possible phonons trajectories in its superconducting state. The state of superconductivity in the matter can be explained only by the phonons behavior peculiarity. And on the basis of the above-mentioned assumption, the corresponding mathematical model is constructed.

  18. Apparatus for characterizing conductivity of superconducting materials

    DOE Patents [OSTI]

    Doss, J.D.

    1993-12-07

    Apparatus and method for noncontact, radio-frequency shielding current characterization of materials. Self- or mutual inductance changes in one or more inductive elements, respectively, occur when materials capable of supporting shielding currents are placed in proximity thereto, or undergo change in resistivity while in place. Such changes can be observed by incorporating the inductor(s) in a resonant circuit and determining the frequency of oscillation or by measuring the voltage induced on a coupled inductive element. The present invention is useful for determining the critical temperature and superconducting transition width for superconducting samples. 10 figures.

  19. On Testing Entropic Inequalities for Superconducting Qudit

    E-Print Network [OSTI]

    Evgenii Glushkov; Anastasiia Glushkova; V. I. Man'ko

    2015-05-20

    The aim of this work is to verify the new entropic and information inequalities for non-composite systems using experimental $5 \\times 5$ density matrix of the qudit state, measured by the tomographic method in a multi-level superconducting circuit. These inequalities are well-known for bipartite and tripartite systems, but have never been tested for superconducting qudits. Entropic inequalities can also be used to evaluate the accuracy of experimental data and the value of mutual information, deduced from them, may charachterize correlations between different degrees of freedom in a noncomposite system.

  20. Induced Magnetism in Color-Superconducting Media

    E-Print Network [OSTI]

    Efrain J. Ferrer

    2010-01-22

    The dense core of compact stars is the natural medium for the realization of color superconductivity. A common characteristic of such astrophysical objects is their strong magnetic fields, especially those of the so called magnetars. In this talk, I discuss how a color superconducting core can generate or/and enhance the stellar magnetic field independently of a magnetohydrodynamic dynamo mechanism. The magnetic field generator is in this case a gluonic current which circulates to stabilize the color superconductor in the presence of a strong magnetic field or under the pairing stress produced in the medium by the neutrality and $\\beta$-equilibrium constraints.

  1. Superconducting nanowire single photon detector on diamond

    SciTech Connect (OSTI)

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

    2014-03-24

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

  2. Superconductivity observed in platinum-silicon interface

    SciTech Connect (OSTI)

    Kuo, Pai-Chia, E-mail: paichia@phys.sinica.edu.tw [Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Chen, Chun-Wei [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Lee, Ku-Pin; Shiue, Jessie, E-mail: yshiue@phys.sinica.edu.tw [Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China)

    2014-05-26

    We report the discovery of superconductivity with an onset temperature of ?0.6?K in a platinum-silicon interface. The interface was formed by using a unique focused ion beam sputtering micro-deposition method in which the energies of most sputtered Pt atoms are ?2.5?eV. Structural and elemental analysis by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy reveal a???7?nm interface layer with abundant Pt, which is the layer likely responsible for the superconducting transport behavior. Similar transport behavior was also observed in a gold-silicon interface prepared by the same technique, indicating the possible generality of this phenomenon.

  3. Apparatus for characterizing conductivity of superconducting materials

    DOE Patents [OSTI]

    Doss, James D. (Los Alamos, NM)

    1993-01-01

    Apparatus and method for noncontact, radio-frequency shielding current characterization of materials. Self- or mutual inductance changes in one or more inductive elements, respectively, occur when materials capable of supporting shielding currents are placed in proximity thereto, or undergo change in resistivity while in place. Such changes can be observed by incorporating the inductor(s) in a resonant circuit and determining the frequency of oscillation or by measuring the voltage induced on a coupled inductive element. The present invention is useful for determining the critical temperature and superconducting transition width for superconducting samples.

  4. Microsoft Word - FCL Testing Report Final.doc

    Office of Environmental Management (EM)

    Southern California Edison territory due to an absence of 138kV substations. Part of the design criteria for the device is to reduce a fault from 63 kA to 40 kA. The design is...

  5. Microsoft Word - FCL Testing Report Final.doc

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPAEnergy May2.docTechnical Consumer Products,An Assessment of

  6. Quantum network of superconducting qubits through opto-mechanical interface

    E-Print Network [OSTI]

    Zhang-qi Yin; W. L. Yang; L. Sun; L. M. Duan

    2015-01-08

    We propose a scheme to realize quantum networking of superconducting qubits based on the opto-mechanical interface. The superconducting qubits interact with the microwave photons, which then couple to the optical photons through the opto-mechanical interface. The interface generates a quantum link between superconducting qubits and optical flying qubits with tunable pulse shapes and carrier frequencies, enabling transmission of quantum information to other superconducting or atomic qubits. We show that the scheme works under realistic experimental conditions and it also provides a way for fast initialization of the superconducting qubits under 1 K instead of 20 mK operation temperature.

  7. Color symmetric superconductivity in a phenomenological QCD model

    E-Print Network [OSTI]

    Henrik Bohr; Constança Providência; João da Providência

    2009-09-19

    In this paper, we construct a theory of the NJL-type where superconductivity is present, and yet the super-conducting state remains, in the average, color symmetric. This shows that the present approach to color superconductivity is consistent with color singlet-ness. Indeed, quarks are free in the deconfined phase, but the deconfined phase itself is believed to be a color singlet. The usual description of the color superconducting state violates color singlet-ness. On the other hand, the color superconducting state here proposed, is color symmetric in the sense that an arbitrary color rotation leads to an equivalent state, with precisely the same physical properties.

  8. Quantum Berezinskii-Kosterlitz-Thouless transition in the superconducting phase of (2+1)-dimensional quantum chromodynamics

    E-Print Network [OSTI]

    Haddad, Laith H

    2015-01-01

    We study superconductivity in the hadron-quark mixed phase of planar quantum chromodynamics within the large $N$ limit of a Gross-Neveu model modified by a repulsive vector term. At zero temperature, we find that reducing the quark density through a critical point destroys superconductivity via a Berezinskii-Kosterlitz-Thouless (BKT) phase transition. Dissolution of logarithmically bound diquarks is caused by chiral mixing in the quark field associated with $\\mathbb{Z}_2 \\otimes \\mathbb{Z}_2 \\to \\mathbb{Z}_2$ chiral symmetry breaking of the Fermi surface. We conjecture that a similar mechanism may underlie holographic BKT transitions.

  9. Superconducting single photon detectors integrated with diamond nanophotonic circuits

    E-Print Network [OSTI]

    Rath, Patrik; Ferrari, Simone; Sproll, Fabian; Lewes-Malandrakis, Georgia; Brink, Dietmar; Ilin, Konstantin; Siegel, Michael; Nebel, Christoph; Pernice, Wolfram

    2015-01-01

    Photonic quantum technologies promise to repeat the success of integrated nanophotonic circuits in non-classical applications. Using linear optical elements, quantum optical computations can be performed with integrated optical circuits and thus allow for overcoming existing limitations in terms of scalability. Besides passive optical devices for realizing photonic quantum gates, active elements such as single photon sources and single photon detectors are essential ingredients for future optical quantum circuits. Material systems which allow for the monolithic integration of all components are particularly attractive, including III-V semiconductors, silicon and also diamond. Here we demonstrate nanophotonic integrated circuits made from high quality polycrystalline diamond thin films in combination with on-chip single photon detectors. Using superconducting nanowires coupled evanescently to travelling waves we achieve high detection efficiencies up to 66 % combined with low dark count rates and timing resolu...

  10. Superconducting DC and RF Properties of Ingot Niobium

    SciTech Connect (OSTI)

    Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel, Ganapati Rao Myneni

    2011-07-01

    The thermal conductivity, DC magnetization and penetration depth of large-grain niobium hollow cylindrical rods fabricated from ingots, manufactured by CBMM subjected to chemical and heat treatment were measured. The results confirm the influence of chemical and heat-treatment processes on the superconducting properties, with no significant dependence on the impurity concentrations in the original ingots. Furthermore, RF properties, such as the surface resistance and quench field of the niobium rods were measured using a TE{sub 011} cavity. The hollow niobium rod is the center conductor of this cavity, converting it to a coaxial cavity. The quench field is limited by the critical heat flux through the rods' cooling channel.

  11. Surface participation and dielectric loss in superconducting qubits

    E-Print Network [OSTI]

    Chen Wang; Christopher Axline; Yvonne Y. Gao; Teresa Brecht; Luigi Frunzio; Michel H. Devoret; Robert J. Schoelkopf

    2015-10-15

    We study the energy relaxation times ($T_1$) of superconducting transmon qubits in 3D cavities as a function of dielectric participation ratios of material surfaces. This surface participation ratio, representing the fraction of electric field energy stored in a dissipative surface layer, is computed by a two-step finite-element simulation and experimentally varied by qubit geometry. With a clean electromagnetic environment and suppressed non-equilibrium quasiparticle density, we find an approximately proportional relation between the transmon relaxation rates and surface participation ratios. These results suggest dielectric dissipation arising from material interfaces is the major limiting factor for the $T_1$ of transmons in 3D cQED architecture. Our analysis also supports the notion of spatial discreteness of surface dielectric dissipation.

  12. Surface participation and dielectric loss in superconducting qubits

    E-Print Network [OSTI]

    Chen Wang; Christopher Axline; Yvonne Y. Gao; Teresa Brecht; Luigi Frunzio; Michel H. Devoret; Robert J. Schoelkopf

    2015-09-06

    We study the energy relaxation times ($T_1$) of superconducting transmon qubits in 3D cavities as a function of dielectric participation ratios of material surfaces. This surface participation ratio, representing the fraction of electric field energy stored in a dissipative surface layer, is computed by a two-step finite-element simulation and experimentally varied by qubit geometry. With a clean electromagnetic environment and suppressed non-equilibrium quasiparticle density, we find an approximately proportional relation between the transmon relaxation rates and surface participation ratios. These results suggest dielectric dissipation arising from material interfaces is the major limiting factor for the $T_1$ of transmons in 3D cQED architecture. Our analysis also supports the notion of spatial discreteness of surface dielectric dissipation.

  13. Cooling of Color Superconducting Compact Stars

    E-Print Network [OSTI]

    David Blaschke

    2006-03-26

    We review the status of research on the cooling of compact stars, with emphasis on the influence of color superconducting quark matter phases. Although a consistent microscopic approach is not yet available, severe constraints on the phase structure of matter at high densities come from recent mass and cooling observations of compact stars.

  14. Low frequency noise in superconducting qubits

    E-Print Network [OSTI]

    Fominov, Yakov

    Low frequency noise in superconducting qubits Lara Faoro and Lev Ioffe Rutgers University (USA) Exp-traps Faoro and Ioffe, PRL 96, 47001 (2006) · a discussion on the mysterious and puzzling flux noise at low... IN PROGRESS WITH EXPERIMENTALISTS! 4. Origin of low frequency flux noise at low temperature ? WHAT THE HELL

  15. Positive and inverse isotope effect on superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-04

    This article improves the BCS theory to include the inverse isotope effect on superconductivity. An affective model can be deduced from the model including electron-phonon interactions, and the phonon-induced attraction is simply and clearly explained on the electron Green function. The focus of this work is on how the positive or inverse isotope effect occurs in superconductors.

  16. Geometrical Dynamics in a Transitioning Superconducting Sphere

    E-Print Network [OSTI]

    James R. Claycomb; Rambis K. Chu

    2006-02-22

    Recent theoretical work has concentrated on calculating the Casimir effect in curved spacetime. In this paper we outline the forward problem of metrical variation due to the Casimir effect for spherical geometries. We consider a scalar quantum field inside a hollow superconducting sphere. Metric equations are developed describing the evolution of the scalar curvature after the sphere transitions to the normal state.

  17. Di-Antiquarks condensation in Color Superconductivity

    E-Print Network [OSTI]

    Fabio L. Braghin

    2006-11-30

    Some consequences of a classical vector field (chromo-electromagnetic field) coupled to quarks, which undergo to superfluid and/or superconductive states with diquark / diantiquark condensation, are investigated. For this, one scalar field exchange is considered in the lines investigated by Pisarski and Rischke \\cite{PISARSKI-RISCHKE} in the mean field approach. Some effects and possible consequences are discussed.

  18. DOE, Texas settle super(conducting) differences

    SciTech Connect (OSTI)

    Crawford, M.

    1994-08-02

    The US DOE agreed to pay over $200 million in cash and transfer $510 million in property to Texas to settle the state`s claims against the federal government for cancellation of the Superconducting Super Collider. This article discusses the settlement and its history and what will be done with the facilities.

  19. Fractons and high-$T_{c}$ superconductivity

    E-Print Network [OSTI]

    Wellington da Cruz; Marcelo Pagotto Carneiro

    2001-01-18

    We consider the concept of fractons in the context of high-$T_{c}$ superconductivity. These objects, which carry rational or irrational quantum numbers, are classified into universal classes $h$ of particles or quasiparticles which obey specific fractal distribution function. We show that the relaxation time associated to Hall conductivity for the superconducting cuprate systems came to out as $\\tau_{H}\\propto T^{-2}$. We also consider the pairing of fractons as a mechanism to produce bosonic systems and therefore superconducting states. For that an effective mass obtained from the propagator of a charge-flux system is considered. In this way, some experimental results of infrared studies of the cuprates for the effective mass, $m^*=m_{e}(1+\\lambda)$, compared with our effective mass expression, $m_{eff}=m(1+s)$, show us that the dominant factor for interactions came from the spin. Thus spin flutuactions as a mechanism of high-$T_{c}$ superconductivity and fractons as quasiparticles are related. An expression to the low temperature specific heat of a quantum liquid of fractons is also obtained.

  20. Mixed normal-superconducting states in the presence of strong electric currents

    E-Print Network [OSTI]

    Yaniv Almog; Bernard Helffer; Xing-Bin Pan

    2015-05-23

    We study the Ginzburg-Landau equations in the presence of large electric currents, that are smaller than the critical current where the normal state losses its stability. For steady-state solutions in the large $\\kappa$ limit, we prove that the superconductivity order parameter is exponentially small in a significant part of the domain, and small in the rest of it. Similar results are obtained for the time-dependent problem, in continuation of the paper by the two first authors [3]. We conclude by obtaining some weaker results, albeit similar, for steady-state solutions in the large domain limit.

  1. Strong Meissner screening change in superconducting radio frequency cavities due to mild baking

    SciTech Connect (OSTI)

    Romanenko, A. Grassellino, A.; Barkov, F.; Suter, A.; Salman, Z.; Prokscha, T.

    2014-02-17

    We investigate “hot” regions with anomalous high field dissipation in bulk niobium superconducting radio frequency cavities for particle accelerators by using low energy muon spin rotation (LE-?SR) on corresponding cavity cutouts. We demonstrate that superconducting properties at the hot region are well described by the non-local Pippard/BCS model for niobium in the clean limit with a London penetration depth ?{sub L}=23±2 nm. In contrast, a cutout sample from the 120??C baked cavity shows a much larger ?>100?nm and a depth dependent mean free path, likely due to gradient in vacancy concentration. We suggest that these vacancies can efficiently trap hydrogen and hence prevent the formation of hydrides responsible for rf losses in hot regions.

  2. Tapering studies for Terawatt level X-ray FELs with a superconducting undulator

    E-Print Network [OSTI]

    Emma, Claudio; Emma, Paul; Huang, Zhirong; Pellegrini, Claudio

    2015-01-01

    We study the tapering optimization scheme for a short period, less than two cm, superconducting undulator, and show that it can generate 4 keV X-ray pulses with peak power in excess of 1 terawatt, using LCLS electron beam parameters. We study the e?ect of undulator module length relative to the FEL gain length for continous and step-wise taper pro?les. For the optimal section length of 1.5m we study the evolution of the FEL process for two di?erent superconducting technologies NbTi and Nb3Sn. We discuss the major factors limiting the maximum output power, particle detrapping around the saturation location and time dependent detrapping due to generation and ampli?cation of sideband modes.

  3. Resonance-valence-bond superconductivity in CuO{sub 2} planes

    SciTech Connect (OSTI)

    Batista, C.D.; Aligia, A.A. [Comision Nacional de Energia Atomico, de Bariloche (Argentina)

    1996-11-01

    The authors find the exact ground state of a system of 4 x 4 unit cells described by an effective model for cuprate superconductors. The model has the form of the t-J one, but includes a three-site term t{double_prime} like that derived from the Hubbard model in the large U limit, but of opposite sign for realistic or large O-O hopping. For t{double_prime} > t{double_prime}{sub c} (where t{double_prime}{sub c}/t {approximately} 0.1 for realistic J and doping) the system undergoes a transition to a phase in which the ground state has a significant overlap with a very simple superconducting resonance-valence-bond (RVB) wave function. In the RVB phase there is a large increase of the d-wave superconducting susceptibility. The authors calculate the boundary of the RVB phase.

  4. Strong Meissner screening change in superconducting radio frequency cavities due to mild baking

    E-Print Network [OSTI]

    Romanenko, A; Barkov, F; Suter, A; Salman, Z; Prokscha, T

    2013-01-01

    We investigate "hot" regions with anomalous high field dissipation in bulk niobium superconducting radio frequency cavities for particle accelerators by using low energy muon spin rotation (LE-$\\mu$SR) on corresponding cavity cutouts. We demonstrate that superconducting properties at the hot region are well described by the non-local Pippard/BCS model for niobium in the clean limit with a London penetration depth $\\lambda_\\mathrm{L} = 23 \\pm 2$ nm. In contrast, a cutout sample from the 120$^\\circ$C baked cavity shows a much larger $\\lambda > 100$ nm and a depth dependent mean free path, likely due to gradient in vacancy concentration. We suggest that these vacancies can efficiently trap hydrogen and hence prevent the formation of hydrides responsible for rf losses in hot regions.

  5. Torsional texturing of superconducting oxide composite articles

    DOE Patents [OSTI]

    Christopherson, Craig John (Grafton, MA); Riley, Jr., Gilbert N. (Marlborough, MA); Scudiere, John (Bolton, MA)

    2002-01-01

    A method of texturing a multifilamentary article having filaments comprising a desired oxide superconductor or its precursors by torsionally deforming the article is provided. The texturing is induced by applying a torsional strain which is at least about 0.3 and preferably at least about 0.6 at the surface of the article, but less than the strain which would cause failure of the composite. High performance multifilamentary superconducting composite articles having a plurality of low aspect ratio, twisted filaments with substantially uniform twist pitches in the range of about 1.00 inch to 0.01 inch (25 to 0.25 mm), each comprising a textured desired superconducting oxide material, may be obtained using this texturing method. If tighter twist pitches are desired, the article may be heat treated or annealed and the strain repeated as many times as necessary to obtain the desired twist pitch. It is preferred that the total strain applied per step should be sufficient to provide a twist pitch tighter than 5 times the diameter of the article, and twist pitches in the range of 1 to 5 times the diameter of the article are most preferred. The process may be used to make a high performance multifilamentary superconducting article, having a plurality of twisted filaments, wherein the degree of texturing varies substantially in proportion to the radial distance from the center of the article cross-section, and is substantially radially homogeneous at any given cross-section of the article. Round wires and other low aspect ratio multifilamentary articles are preferred forms. The invention is not dependent on the melting characteristics of the desired superconducting oxide. Desired oxide superconductors or precursors with micaceous or semi-micaceous structures are preferred. When used in connection with desired superconducting oxides which melt irreversibly, it provides multifilamentary articles that exhibit high DC performance characteristics and AC performance markedly superior to any currently available for these materials. In a preferred embodiment, the desired superconducting oxide material is BSCCO 2223.

  6. Photon-counting optical coherence-domain reflectometry using superconducting single-

    E-Print Network [OSTI]

    Teich, Malvin C.

    Photon-counting optical coherence-domain reflectometry using superconducting single- photon reflecting samples. In particular, we experimentally demonstrate the possibility of using superconducting. Drakinsky, J. Zhang, A. Verevkin, and R. Sobolewski, "Fabrication of nanostructured superconducting single

  7. Color superconductivity with determinant interaction in strange quark matter

    E-Print Network [OSTI]

    Amruta Mishra; Hiranmaya Mishra

    2006-08-28

    We investigate the effect of six fermion determinant interaction on color superconductivity as well as on chiral symmetry breaking. Coupled mass gap equations and the superconducting gap equation are derived through the minimisation of the thermodynamic potential. The effect of nonzero quark -- antiquark condensates on the superconducting gap is derived. This becomes particularly relevant for the case of 2-flavor superconducting matter with unpaired strange quarks in the diquark channel. While the effect of six fermion interaction leads to an enhancement of u-d superconductivity, due to nonvanishing strange quark--antiquark condensates, such an enhancement will be absent at higher densities for u-s or d-s superconductivity due to early (almost) vanishing of light quark-- antiquark condensates.

  8. The ion pairs and superconducting bosons

    E-Print Network [OSTI]

    V. N. Minasyan

    2009-02-11

    First, it is shown that the creation of the spinless ion pairs in the lattice, which are hold by the binding with neighbor ion pairs together regarded as covalent. These ion pairs are created by the repulsive potential interaction of two ions which is bound as linear oscillator. The repulsive S-wave scattering between ion pairs and electrons is transformed to the attractive effective interaction between electrons which leads to a creation of electron pairs by a binding energy depending on the condensate fraction of ion pairs $\\frac{N_0}{N}$. In this respect, the absence of ion pairs in the condensate destroys a binding energy of electron pairs and in turn so-called superconductimg phase. As new result presented theory is that the number of the superconducting bosons is not changed in the superconducting phase.

  9. Superconductivity and Superfluidity as Universal Emergent Phenomena

    E-Print Network [OSTI]

    Guidry, Mike

    2015-01-01

    Superconductivity (SC) or superfluidity (SF) is observed across a remarkably broad range of fermionic systems: in BCS, cuprate, iron-based, organic, and heavy-fermion superconductors, and superfluid helium-3 in condensed matter; in a variety of SC/SF phenomena in low-energy nuclear physics; in ultracold, trapped atomic gases; and in various exotic possibilities in neutron stars. The range of physical conditions and differences in microscopic physics defy all attempts to unify this behavior in any conventional picture. Here we propose a unification through the shared symmetry properties of the emergent condensed states, with microscopic differences absorbed into parameters. This, in turn, forces a rethinking of specific occurrences of SC/SF such as cuprate high-temperature superconductivity, which becomes far less mysterious when seen as part of a continuum of behavior shared by a variety of other systems.

  10. Critical parameters of superconducting materials and structures

    SciTech Connect (OSTI)

    Fluss, M.J.; Howell, R.H.; Sterne, P.A.; Dykes, J.W.; Mosley, W.D.; Chaiken, A.; Ralls, K.; Radousky, H.

    1995-02-01

    We report here the completion of a one year project to investigate the synthesis, electronic structure, defect structure, and physical transport properties of high temperature superconducting oxide materials. During the course of this project we produced some of the finest samples of single crystal detwinned YBa{sub 2}Cu{sub 3}O{sub 7}, and stoichiometrically perfect (Ba,K)BiO{sub 3}. We deduced the Fermi surface of YBa{sub 2}Cu{sub 3}O{sub 7}, (La,Sr){sub 2}CuO{sub 4}, and (Ba,K)BiO{sub 3} through the recording of the electron momentum density in these materials as measured by positron annihilation spectroscopy and angle resolved photoemission. We also performed extensive studies on Pr substituted (Y,Pr)Ba{sub 2}Cu{sub 3}O{sub 7} so as to further understand the origin of the electron pairing leading to superconductivity.

  11. Superconductivity and magnetism in rapidly solidified perovskites

    SciTech Connect (OSTI)

    O'Handley, R.C.; Kalonji, G.

    1991-01-01

    The report is divided into six parts, reflecting major thrusts of our work since 1987. The six areas are: molecular orbital theory of high {Tc} superconductivity; rapid solidification processing of oxide superconductors; time dependent magnetic and superconducting properties of these inhomogeneous materials; excess Gd in Gd{sub 1+x}Ba{sub 2-x}Cu{sub 3}O{sub 7-{delta}} perovskites; rapid solidification and directional annealing to achieve high Jc; and Mossbauer studies of T = Fe, Co and Ni site selection in YBa{sub 2}(CuT){sub 3}O{sub 7-{delta}} and GdBa{sub 2}(CuT){sub 3}O{sub 7-{delta}}.

  12. Composite arrays of superconducting microstrip line resonators

    SciTech Connect (OSTI)

    Mohebbi, H. R. Miao, G. X.; Benningshof, O. W. B.; Taminiau, I. A. J.; Cory, D. G.

    2014-03-07

    A novel design of an array of half-wave superconductive microstrip resonators is described. The resonator is intended to be useful for electron spin resonance studies of thin film samples at cryogenic temperatures. It achieves a high quality factor, has a small mode-volume, and creates a uniform magnetic field in a plane above the resonator. The device is made of thin film Niobium on sapphire wafer and is tested with a static magnetic field. Variation of Q-factor versus the magnetic field's strength at different temperatures is reported and is in a good agreement with simulation when the loss due to the vortices is included. Also, the power-dependence response of the resonator is shown in experiments and is verified by capturing the nonlinearity associated with the surface impedance of the superconducting film into the circuit model of the device.

  13. The superconducting solenoid magnets for MICE

    SciTech Connect (OSTI)

    Green, Michael A.

    2002-12-22

    The Muon Ionization Cooling Experiment (MICE) is a channel of superconducting solenoid magnets. The magnets in MICE are around the RF cavities, absorbers (liquid or solid) and the primary particle detectors [1], [2]. The MICE superconducting solenoid system consists of eighteen coils that are grouped in three types of magnet assemblies. The cooling channel consists of two complete cell of an SFOFO cooling channel. Each cell consists of a focusing coil pair around an absorber and a coupling coil around a RF cavity that re-accelerates the muons to their original momentum. At the ends of the experiment are uniform field solenoids for the particle detectors and a set of matching coils used to match the muon beam to the cooling cells. Three absorbers are used instead of two in order to shield the detectors from dark currents generated by the RF cavities at high operating acceleration gradients.

  14. Digital feedback in superconducting quantum circuits

    E-Print Network [OSTI]

    D. Ristè; L. DiCarlo

    2015-08-06

    This chapter covers the development of feedback control of superconducting qubits using projective measurement and a discrete set of conditional actions, here referred to as digital feedback. We begin with an overview of the applications of digital feedback in quantum computing. We then introduce an implementation of high-fidelity projective measurement of superconducting qubits. This development lays the ground for closed-loop control based on the binary measurement result. A first application of digital feedback control is fast and deterministic qubit reset, allowing the repeated initialization of a qubit more than an order of magnitude faster than its relaxation rate. A second application employs feedback in a multi-qubit setting to convert the generation of entanglement by parity measurement from probabilistic to deterministic, targeting an entangled state with the desired parity every time.

  15. Superconducting cuprate heterostructures for hot electron bolometers

    SciTech Connect (OSTI)

    Wen, B.; Yakobov, R.; Vitkalov, S. A.; Sergeev, A.

    2013-11-25

    Transport properties of the resistive state of quasi-two dimensional superconducting heterostructures containing ultrathin La{sub 2?x}Sr{sub x}CuO{sub 4} layers synthesized using molecular beam epitaxy are studied. The electron transport exhibits strong deviation from Ohm's law, ?V??I{sup 3}, with a coefficient ?(T) that correlates with the temperature variation of the resistivity d?/dT. Close to the normal state, analysis of the nonlinear behavior in terms of electron heating yields an electron-phonon thermal conductance per unit area g{sub e?ph}?1 W/K cm{sup 2} at T = 20 K, one-two orders of magnitude smaller than in typical superconductors. This makes superconducting LaSrCuO heterostructures to be attractive candidate for the next generation of hot electron bolometers with greatly improved sensitivity.

  16. HINS Superconducting Lens and Cryostat Performance

    SciTech Connect (OSTI)

    Page, T.M.; DiMarco, J.; Huang, Y.; Orris, D.F.; Tartaglia, M.A.; Terechkine, I.; Tompkins, J.C.; /Fermilab

    2008-08-01

    Fermi National Accelerator Laboratory is involved in the development of a 60 MeV superconducting linac. This linac is part of the High Intensity Neutrino Source (HINS) R&D Program. The initial beam acceleration in the front end section of the linac is achieved using room temperature spoke cavities, each of which is combined with a superconducting focusing solenoid. These solenoid magnets are cooled with liquid helium at 4.5K, operate at 250 A and have a maximum magnetic field strength of 7.5 T. A prototype solenoid cryostat was built and tested at the Fermilab Magnet Test Facility. This paper discusses the test results of the prototype and compares the measured and estimated performance of the cryostat. We also present the methods and results for measuring and fiducializing the axis of the solenoid lens.

  17. Ted Geballe: A Lifetime of Contributions To Superconductivity

    E-Print Network [OSTI]

    Stewart, G R

    2015-01-01

    The editors have dedicated this special issue on superconducting materials "to Ted Geballe in honor of his numerous seminal contributions to the field of superconducting materials over more than 60 years, on the year of his 95th birthday." Here, as an executive summary, are just a few highlights of his research in superconductivity, leavened with some anecdotes, and ending with some of Teds general insights and words of wisdom.

  18. High temperature superconductivity in metallic region near Mott transition

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-11

    The spin-singlet superconductivity without phonons is examined in consideration of correlations on an extended Hubbard model. It is shown that the superconductivity requires not only the total correlation should be strong enough but also the density of state around Fermi energy should be large enough, which shows that the high temperature superconductivity could only be found in the metallic region near the Mott metal insulator transition (MIT). Other properties of superconductors are also discussed on these conclusions.

  19. Substrates suitable for deposition of superconducting thin films

    DOE Patents [OSTI]

    Feenstra, Roeland (Oak Ridge, TN); Boatner, Lynn A. (Oak Ridge, TN)

    1993-01-01

    A superconducting system for the lossless transmission of electrical current comprising a thin film of superconducting material Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x epitaxially deposited upon a KTaO.sub.3 substrate. The KTaO.sub.3 is an improved substrate over those of the prior art since the it exhibits small lattice constant mismatch and does not chemically react with the superconducting film.

  20. Method for manufacturing a rotor having superconducting coils

    DOE Patents [OSTI]

    Driscoll, David I. (South Euclid, OH); Shoykhet, Boris A. (Beachwood, OH)

    2001-01-01

    A method and apparatus for manufacturing a rotor for use with a rotating machine is provided that employs a superconducting coil on the rotor. An adhesive is applied to an outer surface of the rotor body, which may include a groove disposed within an outer surface of the rotor body. A superconducting coil is then mounted onto the rotor body such that the adhesive bonds the superconducting coil to the rotor body.

  1. Quantum Heat Engines Using Superconducting Quantum Circuits

    E-Print Network [OSTI]

    H. T. Quan; Y. D. Wang; Yu-xi Liu; C. P. Sun; Franco Nori

    2006-09-14

    We propose a quantum analog of the internal combustion engine used in most cars. Specifically, we study how to implement the Otto-type quantum heat engine (QHE) with the assistance of a Maxwell's demon. Three steps are required: thermalization, quantum measurement, and quantum feedback controlled by the Maxwell demon. We derive the positive-work condition of this composite QHE. Our QHE can be constructed using superconducting quantum circuits. We explicitly demonstrate the essential role of the demon in this macroscopic QHE.

  2. Electromagnetic Modelling of Superconducting Sensor Designs

    E-Print Network [OSTI]

    Gerra, Guido

    OF MATERIALS SCIENCE AND METALLURGY Electromagnetic Modelling of Superconducting Sensor Designs Guido Gerra Clare Hall, University of Cambridge 1 Preface The present dissertation has been submitted for the degree of Master... in the current circulating in it to the magnetic field the SQUID is subjected to. This possibility arises from the dynamics of electromagnetic fields in superconductors combined with the Josephson effect, and appropriate coupling schemes can be used to measure...

  3. Holographic Superconductivity with Gauss-Bonnet gravity

    E-Print Network [OSTI]

    Ruth Gregory

    2010-12-07

    I review recent work on holographic superconductivity with Einstein-Gauss-Bonnet gravity, and show how the critical temperature of the superconductor depends on both gravitational backreaction and the Gauss-Bonnet parameter, using both analytic and numerical arguments. I also review computations of the conductivity, finding the energy gap, and demonstrating that there is no universal gap ratio, $\\omega_g/T_c$, for these superconductors.

  4. On a Model of Superconductivity and Biology

    E-Print Network [OSTI]

    Monica De Angelis

    2012-03-02

    The paper deals with a semilinear integrodifferential equation that characterizes several dissipative models of Viscoelasticity, Biology and Superconductivity. The initial - boundary problem with Neumann conditions is analyzed. When the source term F is a linear function, then the explicit solution is obtained. When F is non linear, some results on existence, uniqueness and a priori estimates are deduced. As example of physical model the reaction - diffusion system of Fitzhugh Nagumo is considered.

  5. Holographic Competition of Phases and Superconductivity

    E-Print Network [OSTI]

    Kiritsis, Elias

    2015-01-01

    We use a holographic theory to model and study the competition of four phases: an antiferromagnetic phase, a superconducting phase, a metallic phase and a striped phase, using as control parameters temperature and a doping-like parameter. We analyse the various instabilities and determine the possible phases. One class of phase diagrams, that we analyse in detail, is similar to that of high-temperature superconductors as well as other strange metal materials.

  6. Dual superconducting properties of the QCD vacuum

    E-Print Network [OSTI]

    A. D'Alessandro; M. D'Elia

    2005-10-27

    A consistent description of the confining QCD vacuum as a dual superconductor requires a determination of fundamental parameters such as the superconductor correlation length $\\xi$ and the field penetration depth $\\lambda$, which determine whether the superconductor is of type I or type II. We illustrate preliminary results of a lattice determination of $\\xi$ for the case of pure Yang-Mills with two colors, obtained by measuring the temporal correlator of a disorder parameter detecting dual superconductivity.

  7. Rotor assembly including superconducting magnetic coil

    DOE Patents [OSTI]

    Snitchler, Gregory L. (Shrewsbury, MA); Gamble, Bruce B. (Wellesley, MA); Voccio, John P. (Somerville, MA)

    2003-01-01

    Superconducting coils and methods of manufacture include a superconductor tape wound concentrically about and disposed along an axis of the coil to define an opening having a dimension which gradually decreases, in the direction along the axis, from a first end to a second end of the coil. Each turn of the superconductor tape has a broad surface maintained substantially parallel to the axis of the coil.

  8. Robust manipulation of superconducting qubits in the presence of fluctuations

    E-Print Network [OSTI]

    Daoyi Dong; Chunlin Chen; Bo Qi; Ian R. Petersen; Franco Nori

    2014-08-07

    Superconducting quantum systems are promising candidates for quantum information processing due to their scalability and design flexibility. However, the existence of defects, fluctuations, and inaccuracies is unavoidable for practical superconducting quantum circuits. In this paper, a sampling-based learning control (SLC) method is used to guide the design of control fields for manipulating superconducting quantum systems. Numerical results for one-qubit systems and coupled two-qubit systems show that the "smart" fields learned using the SLC method can achieve robust manipulation of superconducting qubits even in the presence of large fluctuations and inaccuracies.

  9. Minicourse in Recife Title Spectral methods in superconductivity by ...

    E-Print Network [OSTI]

    2008-02-27

    potential plays an important role in the understanding of the mechanism of the onset of superconductivity for a sample submitted to an external magnetic field.

  10. Superconducting properties in tantalum decorated three-dimensional...

    Office of Scientific and Technical Information (OSTI)

    properties in tantalum decorated three-dimensional graphene and carbon structures Citation Details In-Document Search Title: Superconducting properties in tantalum...

  11. Magnetic pinning of flux lattice in superconducting-nanomagnet hybrids

    E-Print Network [OSTI]

    2011-01-01

    of flux lattice in superconducting-nanomagnet hybrids D.This plays a key role in superconductor properties such as ?ingre- dients in superconductor based applications. The

  12. VACUUM IMPREGNATION WITH EPOXY OF LARGE SUPERCONDUCTING MAGNET STRUCTURES

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01

    Achieved (A) Maximum Superconductor Matrix Current DensityZone (Quench) in a Superconductor by Local Energy Release"High Current Density Superconducting Solenoids for Use in

  13. New Superconducting Magnet Will Lead to Next Generation of Wind...

    Energy Savers [EERE]

    DOE funded AML's design for a superconducting generator for large-scale, high-efficiency offshore wind turbines. AML worked with its partners, Emerson Electric Corporation, Creare...

  14. Intertwining of Superconductivity and Magnetism | U.S. DOE Office...

    Office of Science (SC) Website

    Intertwining of Superconductivity and Magnetism Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy...

  15. Damping and support in high-temperature superconducting levitation systems

    DOE Patents [OSTI]

    Hull, John R. (Sammamish, WA); McIver, Carl R. (Everett, WA); Mittleider, John A. (Kent, WA)

    2009-12-15

    Methods and apparatuses to provide improved auxiliary damping for superconducting bearings in superconducting levitation systems are disclosed. In a superconducting bearing, a cryostat housing the superconductors is connected to a ground state with a combination of a damping strip of material, a set of linkage arms to provide vertical support, and spring washers to provide stiffness. Alternately, the superconducting bearing may be supported by a cryostat connected to a ground state by posts constructed from a mesh of fibers, with the damping and stiffness controlled by the fiber composition, size, and mesh geometry.

  16. Vital Tool in Superconductivity Studies | ornl.gov

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

    Short Title Neutron scattering continues as a vital tool in superconductivity studies January 01, 2011 In 2008, the totally unexpected discovery of a New class of superconductors,...

  17. A young person's view of the Superconducting Super Collider

    SciTech Connect (OSTI)

    Moya, A.

    1990-08-01

    This report gives a simple description of the Superconducting Super Collider, how it works, and what it is used for. (LSP)

  18. Ultrasonic signatures at the superconducting and the pseudogap...

    Office of Scientific and Technical Information (OSTI)

    NEUTRONS; PHASE DIAGRAMS; SCATTERING; SUPERCONDUCTIVITY; SUPERCONDUCTORS; THERMODYNAMICS; ULTRASONIC WAVES Word Cloud More Like This Full Text File size NAView Full Text...

  19. J. Robert Schrieffer and the BCS Theory of Superconductivity

    Office of Scientific and Technical Information (OSTI)

    Walls; Physical Review B, Vol. 57, Issue 22: 14433-14439, June 1, 1998 Top Additional Web Pages: Landmarks: Superconductivity Explained, American Physical Society (APS) John...

  20. High Power Superconducting Continuous Wave Linacs for Protons...

    Office of Science (SC) Website

    Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of...

  1. Anomalous Zeeman response of the coexisting superconducting and...

    Office of Scientific and Technical Information (OSTI)

    Anomalous Zeeman response of the coexisting superconducting and spin-density-wave phases as a probe of extended s -wave pairing in ferropnictide superconductors Prev Next ...

  2. Systems Reiter, George 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY...

    Office of Scientific and Technical Information (OSTI)

    Compton Scattering as a Probe of Hydrogen Bonded (and other) Systems Reiter, George 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 77 NANOSCIENCE AND...

  3. Superconductivity, superfluidity and zero-point oscillations

    E-Print Network [OSTI]

    B. V. Vasiliev

    2013-06-29

    Currently it is thought that in order to explain the phenomenon of superconductivity is necessary to understand the mechanism of formation of electron pairs. However, the paired electrons cannot form a superconducting condensate. They perform disorderly zero-point oscillations and there are no attractive forces in their ensemble. To create a unified ensemble of particles, the pairs must order their zero-point fluctuations so that an attraction between the particles appears. For this reason, the ordering of zero-point oscillations in the electron gas is the cause of superconductivity and the parameters characterizing this order determine the properties of superconductors. The model of condensation of zero-point oscillations creates the possibility to obtain estimates for the critical parameters of elementary superconductors, which are also in the satisfactory agreement with measured data. On the another hand, the phenomenon of superfluidity in He-4 and He-3 can be similarly explained due to the ordering of zero-point fluctuations. Thus it is established that the both related phenomena are based on the same physical mechanism.

  4. Color superconducting quark matter in compact stars

    E-Print Network [OSTI]

    D. B. Blaschke; T. Klahn; F. Sandin

    2007-12-02

    Recent indications for high neutron star masses (M \\sim 2 M_sun) and large radii (R > 12 km) could rule out soft equations of state and have provoked a debate whether the occurence of quark matter in compact stars can be excluded as well. We show that modern quantum field theoretical approaches to quark matter including color superconductivity and a vector meanfield allow a microscopic description of hybrid stars which fulfill the new, strong constraints. For these objects color superconductivity turns out to be an essential ingredient for a successful description of the cooling phenomenology in accordance with recently developed tests. We discuss the energy release in the neutrino untrapping transition as a new aspect of the problem that hybrid stars masquerade themselves as neutron stars. Quark matter searches in future generations of low-temperature/high-density nucleus-nucleus collision experiments such as low-energy RHIC and CBM @ FAIR might face the same problem of an almost crossover behavior of the deconfinement transition. Therefore, diagnostic tools shall be derived from effects of color superconductivity.

  5. Universal scaling of the critical temperature for thin films near the superconducting-to-insulating transition

    E-Print Network [OSTI]

    Ivry, Yachin

    Thin superconducting films form a unique platform for geometrically confined, strongly interacting electrons. They allow an inherent competition between disorder and superconductivity, which in turn enables the intriguing ...

  6. THE MEASUREMENT AND THEORETICAL CALCULATION OF QUENCH VELOCITIES WITHIN LARGE FULLY EPOXY IMPREGNATED SUPERCONDUCTING COILS

    E-Print Network [OSTI]

    Eberhard, P.H.

    2010-01-01

    Quenching of Technical Superconductors by Heat and Magneticamic Aspects of the Superconductive Transition Process,"in J. William Superconductivity and It's Applications. [10

  7. CONSTRUCTION AND TESTING OF THE TWO METER DIAMETER TPC THIN SUPERCONDUCTING SOLENOID

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    DIAMETER TPC THIN SUPERCONDUCTING SOLENOID . 'i.A. Green,an Aluminum Stabilized Superconductor", Cryogenics 17, Vol.and Construction of a Superconducting Stabilized Aluminum

  8. Suppressible pinning of Abrikosov vortices : effects of magnetic vortex arrays on thin superconducting films

    E-Print Network [OSTI]

    Smith, Kevin Daniel

    2008-01-01

    penetration through the superconductive film as it relatesThus, to sustain superconductivity throughout the materialthe mixed state, type-II superconductors have characteristic

  9. Polaronic Effect and Its Impact on T c for Novel Layered Superconducting Systems

    E-Print Network [OSTI]

    Kresin, Vladimir

    2010-01-01

    is bene?cial for superconductivity? As is known, polaronicproperties of novel superconductors, especially the high-T cc for Novel Layered Superconducting Systems Vladimir Kresin

  10. Magnetism and superconductivi[t]y in Pr-based filled skutterudite arsenides

    E-Print Network [OSTI]

    Sayles, Todd Allen

    2008-01-01

    1.5 Superconductivity . . . . . . . . . . . . . . . . . . .and M. B. Maple, ”Superconductivity and non-Fermi liquidSAN DIEGO Magnetism and Superconductiviy in Pr-based Filled

  11. A superconducting bolometer with strong electrothermal feedback Adrian T. Leea)

    E-Print Network [OSTI]

    Richards, Paul L.

    5 July 1996 We present a theoretical analysis and experimental evaluation of a transition-edge superconducting bolometer for detecting infrared and millimeter waves. The superconducting film is voltage biased maintains the sensor temperature within the transition, gives a current responsivity that is simply

  12. TRANSITION-EDGE SUPERCONDUCTING ANTENNA-COUPLED BOLOMETER

    E-Print Network [OSTI]

    , such as Plank and Boomerang. The SAMBA architecture allows for a high density of pixels in the focal plane, Anastasios Vayonakis, Jonas Zmuidzinas California Institute of Technology, Pasadena, CA 91125, USA James J superconducting bolometer (TES). The coupling architecture involves propagating the signal along superconducting

  13. A new boson-fermion model of superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2012-10-09

    It is shown that the superconducting energy gap necessarily lead to the disappearance of some quasi-electrons, thus we suggest a new boson-fermion Hamiltonian to describe superconductivity. The new supercurrent equations are derived with this Hamiltonian. Some new results can be found besides the zero resistance effect, the Meissner effect and the magnetic flux quantum can be explained.

  14. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.; Uherka, K.L.; Abdoud, R.G.

    1996-09-10

    A high temperature superconducting bearing including a permanent magnet rotor levitated by a high temperature superconducting structure is disclosed. The rotor preferably includes one or more concentric permanent magnet rings coupled to permanent magnet ring structures having substantially triangular and quadrangular cross-sections. Both alternating and single direction polarity magnet structures can be used in the bearing. 9 figs.

  15. Superconducting magnetic energy storage for asynchronous electrical systems

    DOE Patents [OSTI]

    Boenig, H.J.

    1984-05-16

    It is an object of the present invention to provide superconducting magnetic energy storage for a plurality of asynchronous electrical systems. It is a further object of the present invention to provide load leveling and stability improvement in a plurality of independent ac systems using a single superconducting magnetic energy storage coil.

  16. Superconducting articles, and methods for forming and using same

    DOE Patents [OSTI]

    Knoll, Allan Robert (Guilderland, NY); Lenseth, Kenneth Patrick (Wynantskill, NY)

    2007-01-09

    A superconducting tape is disclosed, including a substrate having a first surface and a second surface opposite the first surface, the substrate including a plurality of indicia provided on the first surface spaced apart along a length of the substrate; and a superconductor layer overlying the second surface. Also disclosed are components incorporating superconducting tapes, methods for manufacturing same, and methods for using same.

  17. EIS-0138-S: Superconducting Super Collider, Supplemental, Waxahatchie, Texas

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this supplementary statement to analyze the environmental impacts of design modifications to the Superconducting Super Collider that were made following the publication of the Record of Decision that selected Ellis County, Texas, as the location of the laboratory facility. This statement supplements DOE/EIS-0138, Superconducting Super Collider.

  18. Damping in high-temperature superconducting levitation systems

    DOE Patents [OSTI]

    Hull, John R.

    2009-12-15

    Methods and apparatuses for improved damping in high-temperature superconducting levitation systems are disclosed. A superconducting element (e.g., a stator) generating a magnetic field and a magnet (e.g. a rotor) supported by the magnetic field are provided such that the superconducting element is supported relative to a ground state with damped motion substantially perpendicular to the support of the magnetic field on the magnet. Applying this, a cryostat housing the superconducting bearing may be coupled to the ground state with high damping but low radial stiffness, such that its resonant frequency is less than that of the superconducting bearing. The damping of the cryostat may be substantially transferred to the levitated magnetic rotor, thus, providing damping without affecting the rotational loss, as can be derived applying coupled harmonic oscillator theory in rotor dynamics. Thus, damping can be provided to a levitated object, without substantially affecting the rotational loss.

  19. Crossover from a pseudogap state to a superconducting state

    E-Print Network [OSTI]

    Tian De Cao

    2011-02-10

    On the basis of our calculation we deduce that the particular electronic structure of cuprate superconductors confines Cooper pairs to be firstly formed in the antinodal region which is far from the Fermi surface, and these pairs are incoherent and result in the pseudogap state. With the change of doping or temperature, some pairs are formed in the nodal region which locates the Fermi surface, and these pairs are coherent and lead to superconductivity. Thus the coexistence of the pseudogap and the superconducting gap is explained when the two kinds of gaps are not all on the Fermi surface. It is also shown that the symmetry of the pseudogap and the superconducting gap are determined by the electronic structure, and non-s wave symmetry gap favors the high-temperature superconductivity. Why the high-temperature superconductivity occurs in the metal region near the Mott metal-insulator transition is also explained.

  20. Nanoscale constrictions in superconducting coplanar waveguide resonators

    SciTech Connect (OSTI)

    Jenkins, Mark David; Naether, Uta; Ciria, Miguel; Zueco, David; Luis, Fernando; Sesé, Javier; Atkinson, James; Barco, Enrique del; Sánchez-Azqueta, Carlos; Majer, Johannes

    2014-10-20

    We report on the design, fabrication, and characterization of superconducting coplanar waveguide resonators with nanoscopic constrictions. By reducing the size of the center line down to 50?nm, the radio frequency currents are concentrated and the magnetic field in its vicinity is increased. The device characteristics are only slightly modified by the constrictions, with changes in resonance frequency lower than 1% and internal quality factors of the same order of magnitude as the original ones. These devices could enable the achievement of higher couplings to small magnetic samples or even to single molecular spins and have applications in circuit quantum electrodynamics, quantum computing, and electron paramagnetic resonance.

  1. Conceptual Design for Superconducting Planar Helical Undulator

    SciTech Connect (OSTI)

    Sasaki, Shigemi

    2004-05-12

    A preliminary consideration was made on a short-period superconducting planar helical undulator (SCHU) for circularly polarized radiation. The SCHU consists of coils and iron poles/yokes. There is no magnetic structure in the horizontal plane of the electron orbit. The SCHU would provide the large horizontal aperture needed to allow injection into the storage ring. The expected field strength is at least 30% larger than that by an APPLE-type permanent-magnet device with the same gap and the same period.

  2. BNl 703 MHz superconducting RF cavity testing

    SciTech Connect (OSTI)

    Sheehy, B.; Altinbas, Z.; Burrill, A.; Ben-Zvi, I.; Gassner, D.; Hahn, H.; Hammons, L.; Jamilkowski, J.; Kayran, D.; Kewisch, J.; Laloudakis, N.; Lederle, D.; Litvinenko, V.; McIntyre, G.; Pate, D.; Phillips, D.; Schultheiss, C.; Seda,T.; Than, R.; Xu, W.; Zaltsman, A.; Schultheiss, T.

    2011-03-28

    The BNL 5-cell, 703 MHz superconducting accelerating cavity has been installed in the high-current ERL experiment. This experiment will function as a proving ground for the development of high-current machines in general and is particularly targeted at beam development for an electron-ion collider (eRHIC). The cavity performed well in vertical tests, demonstrating gradients of 20 MV/m and a Q{sub 0} of 1e10. Here we will present its performance in the horizontal tests, and discuss technical issues involved in its implementation in the ERL.

  3. Lattice Vibrations and Superconductivity in Layered Structures 

    E-Print Network [OSTI]

    Allen, Roland E.; Alldredg, GP; WETTE, FWD.

    1970-01-01

    VOLUME 2, NUMBER 7 1 OCTOB ER, 1970 Lattice Vibrations and Superconductivity in Layered Structures* B. E. Allen, G. P. Alldredge, and F. W. de bette DePartment of Physics, University of Texas, Austin, Texas 78712 (Received 18 May 1970) In order...-layer films with masses m and M. 2 2570 LATTICE VIBRATIONS AND SUPE RCONDUCTIVITY IN ' ' ' 2571 tion in the o. direction (a = x, y, or z) for a particle in this monolayer vibrating in the mode with fre- quency e, and the other symbols have been defined...

  4. Quantum State Synthesis of Superconducting Resonators

    E-Print Network [OSTI]

    Roshan Sharma; Frederick W. Strauch

    2015-03-07

    We present a theoretical analysis of different methods to synthesize entangled states of two superconducting resonators. These methods use experimentally demonstrated interactions of resonators with artificial atoms, and offer efficient routes to generate nonclassical states. We analyze the theoretical structure of these algorithms and their average performance for arbitrary states and for deterministically preparing NOON states. Using a new state synthesis algorithm, we show that NOON states can be prepared in a time linear in the desired photon number and without any state-selective interactions.

  5. Dual Superconductivity in G2 group

    E-Print Network [OSTI]

    G. Cossu; M. D'Elia; A. Di Giacomo; B. Lucini; C. Pica

    2006-09-28

    We investigate the dual superconductivity mechanism in the exceptional group $G_2$. This is a centerless group (no 't Hooft flux vortices are allowed) and we check for the presence of a magnetic monopole condensate in the confined phase by measuring on the lattice a disorder parameter related to the vacuum expectation value of an operator carrying magnetic charge. The behaviour of the disorder parameter is consistent with the dual superconductor picture. A first step of an analysis on the thermodynamical properties of the theory is conducted by mean of this operator.

  6. Vacuum coupling of rotating superconducting rotor

    DOE Patents [OSTI]

    Shoykhet, Boris A.; Zhang, Burt Xudong; Driscoll, David Infante

    2003-12-02

    A rotating coupling allows a vacuum chamber in the rotor of a superconducting electric motor to be continually pumped out. The coupling consists of at least two concentric portions, one of which is allowed to rotate and the other of which is stationary. The coupling is located on the non-drive end of the rotor and is connected to a coolant supply and a vacuum pump. The coupling is smaller in diameter than the shaft of the rotor so that the shaft can be increased in diameter without having to increase the size of the vacuum seal.

  7. Dependence of the microwave surface resistance of superconducting niobium on the magnitude of the rf field

    SciTech Connect (OSTI)

    Romanenko, A.; Grassellino, A. [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)] [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

    2013-06-24

    Utilizing difference in temperature dependencies we decoupled Bardeen-Cooper-Schrieffer (BCS) and residual components of the microwave surface resistance of superconducting niobium at all rf fields up to B{sub rf}{approx}115 mT. We reveal that the residual resistance decreases with field at B{sub rf} Less-Than-Or-Equivalent-To 40 mT and strongly increases in chemically treated niobium at B{sub rf}>80 mT. We find that BCS surface resistance is weakly dependent on field in the clean limit, whereas a strong and peculiar field dependence emerges after 120 Degree-Sign C vacuum baking.

  8. Superconductivity and topological numbers in the Hubbard chain with bond-charge interaction

    SciTech Connect (OSTI)

    Aligia, A.A.; Hallberg, K.; Batista, C.D.; Ortiz, G.

    1999-12-01

    The authors determine the quantum phase diagram of the Hubbard chain with electron-hole symmetric correlated hopping at 1/2- and 1/4-filling using geometric concepts and continuum limit field theory. The long distance behavior of various correlation functions show a very rich phase diagram with several insulating, metallic, and superconducting phases, which might be relevant to (TMTSF){sub 2}X compounds. The closing of charge and spin gaps are accurately resolved as topological transitions (jumps in {pi} of Berry phases). The metallic or insulating character of each thermodynamic phase is obtained from the ground-state expectation value of a displacement operator in reciprocal space.

  9. Topological Change of the Fermi Surface in Low-Density Rashba Gases: Application to Superconductivity

    E-Print Network [OSTI]

    Cappelluti, Emmanuele

    to Superconductivity E. Cappelluti,1,2 C. Grimaldi,3,4 and F. Marsiglio4,5 1 SMC-INFM, CNR-INFM, via dei Taurini 19 consequences on the onset of the superconducting instability. We show that the superconducting critical with strong spin- orbit coupling are good candidates for enhanced superconductivity. DOI: 10.1103/Phys

  10. Development of the conventional facilities of the Superconducting Super Collider. Revision 1

    SciTech Connect (OSTI)

    Toohig, T.E.

    1994-02-01

    This report discusses an overview of the construction of facilities at the Superconducting Super Collider.

  11. Design of the Prototypical Cryomodule for the EUROTRANS Superconducting Linac for Nuclear Waste Transmutation

    E-Print Network [OSTI]

    Barbanotti, S; Blache, P; Commeaux, C; Duthil, P; Panzeri, N; Pierini, P; Rampnoux, E; Souli, M

    2008-01-01

    Design of the Prototypical Cryomodule for the EUROTRANS Superconducting Linac for Nuclear Waste Transmutation

  12. CERN 6 Tesla superconducting persistent dipole/Filming an experiment/Synchrotron radiation from protons

    E-Print Network [OSTI]

    1979-01-01

    CERN 6 Tesla superconducting persistent dipole/Filming an experiment/Synchrotron radiation from protons

  13. Localization of metal-induced gap states at the metal-insulator interface: Origin of flux noise in SQUIDs and superconducting qubits

    SciTech Connect (OSTI)

    Choi, SangKook; Lee, Dung-Hai; Louie, Steven G.; Clarke, John

    2009-10-10

    The origin of magnetic flux noise in Superconducting Quantum Interference Devices with a power spectrum scaling as 1/f (f is frequency) has been a puzzle for over 20 years. This noise limits the decoherence time of superconducting qubits. A consensus has emerged that the noise arises from fluctuating spins of localized electrons with an areal density of 5 x 10(17)m(-2). We show that, in the presence of potential disorder at the metal-insulator interface, some of the metal-induced gap states become localized and produce local moments. A modest level of disorder yields the observed areal density.

  14. Constraining crystalline color superconducting quark matter with gravitational-wave data

    E-Print Network [OSTI]

    Lap-Ming Lin

    2007-10-15

    We estimate the maximum equatorial ellipticity sustainable by compact stars composed of crystalline color-superconducting quark matter. For the theoretically allowed range of the gap parameter $\\Delta$, the maximum ellipticity could be as large as $10^{-2}$, which is about 4 orders of magnitude larger than the tightest upper limit obtained by the recent science runs of the LIGO and GEO600 gravitational wave detectors based on the data from 78 radio pulsars. We point out that the current gravitational-wave strain upper limit already has some implications for the gap parameter. In particular, the upper limit for the Crab pulsar implies that $\\Delta$ is less than O(20) MeV for a range of quark chemical potential accessible in compact stars, assuming that the pulsar has a mass $1.4 M_{\\odot}$, radius 10 km, breaking strain $10^{-3}$, and that it has the maximum quadrupole deformation it can sustain without fracturing.

  15. Superconducting 112 MHz QWR electron gun

    SciTech Connect (OSTI)

    Belomestnykh, S.; Ben-Zvi, I.; Boulware, C.H.; Chang, X.; Grimm, T.L.; Rao, T.; Siegel, B.; Skaritka, J.; Than, R.; Winowski, M.; Wu, Q.; Xin, T.; Xue, L.

    2011-07-25

    Brookhaven National Laboratory and Niowave, Inc. have designed and fabricated a superconducting 112 MHz quarter-wave resonator (QWR) electron gun. The first cold test of the QWR cryomodule has been completed at Niowave. The paper describes the cryomodule design, presents the cold test results, and outline plans to upgrade the cryomodule. Future experiments include studies of different photocathodes and use for the coherent electron cooling proof-of-principle experiment. Two cathode stalk options, one for multi-alkali photocathodes and the other one for a diamond-amplified photocathode, are discussed. A quarter-wave resonator concept of superconducting RF (SRF) electron gun was proposed at BNL for electron cooling hadron beams in RHIC. QWRs can be made sufficiently compact even at low RF frequencies (long wavelengths). The long wavelength allows to produce long electron bunches, thus minimizing space charge effects and enabling high bunch charge. Also, such guns should be suitable for experiments requiring high average current electron beams. A 112 MHz QWR gun was designed, fabricated, and cold-tested in collaboration between BNL and Niowave. This is the lowest frequency SRF gun ever tested successfully. In this paper we describe the gun design and fabrication, present the cold test results, and outline our plans. This gun will also serve as a prototype for a future SRF gun to be used for coherent electron cooling of hadrons in eRHIC.

  16. Extended Supersymmetry in Gapped and Superconducting Graphene

    E-Print Network [OSTI]

    V. K. Oikonomou

    2015-06-27

    In view of the many quantum field theoretical descriptions of graphene in $2+1$ dimensions, we present another field theoretical feature of graphene, in the presence of defects. Particularly, we shall be interested in gapped graphene in the presence of a domain wall and also for superconducting graphene in the presence of a vortex. As we explicitly demonstrate, the gapped graphene electrons that are localized on the domain wall are associated with four $N=2$ one dimensional supersymmetries, with each pair combining to form an extended $N=4$ supersymmetry with non-trivial topological charges. The case of superconducting graphene is more involved, with the electrons localized on the vortex being associated with $n$ one dimensional supersymmetries, which in turn combine to form an $N=2n$ extended supersymmetry with no-trivial topological charges. As we shall prove, all supersymmetries are unbroken, a feature closely related to the number of the localized fermions and also to the exact form of the associated operators. In addition, the corresponding Witten index is invariant under compact and odd perturbations.

  17. Status of the SUNY superconducting RFQ

    SciTech Connect (OSTI)

    Jain, A.; Ben-Zvi, I.; Paul, P.; Wang, H. (Brookhaven National Lab., Upton, NY (United States)); Lombardi, A. (Istituto Nazionale di Fisica Nucleare, Legnaro (Italy). Lab. Nazionale di Legnaro)

    1991-01-01

    A RFQ resonator is presently being developed at SUNY. This resonator is a prototype for a chain of six short ({approximately}0.5m long), superconducting (Pb plated Cu), 50 MHz resonators designed to accelerate beam from {beta} = 0.01 to 0.05. The chain accepts a prebunched beam to save on superconducting length. The resonators are of four-rods type with vane-like electrodes. The prototype resonator is designed to accelerate ions of q/A = 1/6 from {beta} = 0.030 to 0.036, operating at a peak surface electric field of 16 MV/m. The electrodes have a rather high modulation parameter of 4 and a wide aperture of 1.57 cm radius. These values are chosen to maximize the accelerating field (E{sub a}) for a given peak surface electric field (E{sub s}). At the design value of E{sub s} = 16 MV/m, the resonator is estimated to have E{sub a} = 2.0 MV/m, stored energy of 4 J, peak surface magnetic field of 360 Gauss, and inter-vane voltage of 0.42 MV. Results of RF tests on this prototype resonator will be presented. 7 refs., 3 figs.

  18. Superconducting materials for large scale applications

    SciTech Connect (OSTI)

    Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

    2004-05-06

    Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

  19. Semiconductor-inspired superconducting quantum computing

    E-Print Network [OSTI]

    Yun-Pil Shim; Charles Tahan

    2015-07-28

    Superconducting circuits offer tremendous design flexibility in the quantum regime culminating most recently in the demonstration of few qubit systems supposedly approaching the threshold for fault-tolerant quantum information processing. Competition in the solid-state comes from semiconductor qubits, where nature has bestowed some almost magical and very useful properties which can be utilized for spin qubit based quantum computing. Here we begin to explore how selective design principles deduced from spin-based systems could be used to advance superconducting qubit science. We take an initial step along this path proposing an encoded qubit approach realizable with state-of-the-art tunable Josephson junction qubits. Our results show that this design philosophy holds promise, enables microwave-free control with minimal overhead (zero overhead in 2-qubit gates), and offers a pathway to future qubit designs with new capabilities such as with higher fidelity or, perhaps, operation at higher temperature. The approach is especially suited to qubits based on variable super-semi junctions.

  20. Superconducting Accelerating Cavity Pressure Sensitivity Analysis and Stiffening

    SciTech Connect (OSTI)

    Rodnizki, J [Soreq NRC, Yavne, Israel; Ben Aliz, Y [Soreq NRC, Yavne, Israel; Grin, A [Soreq NRC, Yavne, Israel; Horvitz, Z [Soreq NRC, Yavne, Israel; Perry, A [Soreq NRC, Yavne, Israel; Weissman, L [Soreq NRC, Yavne, Israel; Davis, G Kirk [JLAB; Delayen, Jean R. [Old Dominion Universtiy

    2014-12-01

    The Soreq Applied Research Accelerator Facility (SARAF) design is based on a 40 MeV 5 mA light ions superconducting RF linac. Phase-I of SARAF delivers up to 2 mA CW proton beams in an energy range of 1.5 - 4.0 MeV. The maximum beam power that we have reached is 5.7 kW. Today, the main limiting factor to reach higher ion energy and beam power is related to the HWR sensitivity to the liquid helium coolant pressure fluctuations. The HWR sensitivity to helium pressure is about 60 Hz/mbar. The cavities had been designed, a decade ago, to be soft in order to enable tuning of their novel shape. However, the cavities turned out to be too soft. In this work we found that increasing the rigidity of the cavities in the vicinity of the external drift tubes may reduce the cavity sensitivity by a factor of three. A preliminary design to increase the cavity rigidity is presented.

  1. Scanning Josephson Tunneling Microscopy of Single Crystal Bi2Sr2CaCu2O8+delta with a Conventional Superconducting Tip

    E-Print Network [OSTI]

    Kimura, H.

    2010-01-01

    +? with a Conventional Superconducting Tip Hikari Kimura,1,2between a conventional superconducting scanning tunnelinginhomogeneity in the superconductivity of BSCCO. The

  2. Probing the Superconducting Order Parameter of High-Tc Superconductor Bi2Sr2CaCu2O8+? by Scanning Josephson Tunneling Microscopy

    E-Print Network [OSTI]

    Kimura, Hikari

    2009-01-01

    Turner, Principles of Superconductive Devices and Circuits (P. G. de Gennes, Superconductivity , edited by R. D. Parks (Tinkham, Introduction to Superconductivity (McGraw-Hill, New

  3. Method for forming bismuth-based superconducting ceramics

    DOE Patents [OSTI]

    Maroni, Victor A.; Merchant, Nazarali N.; Parrella, Ronald D.

    2005-05-17

    A method for reducing the concentration of non-superconducting phases during the heat treatment of Pb doped Ag/Bi-2223 composites having Bi-2223 and Bi-2212 superconducting phases is disclosed. A Pb doped Ag/Bi-2223 composite having Bi-2223 and Bi-2212 superconducting phases is heated in an atmosphere having an oxygen partial pressure not less than about 0.04 atmospheres and the temperature is maintained at the lower of a non-superconducting phase take-off temperature and the Bi-2223 superconducting phase grain growth take-off temperature. The oxygen partial pressure is varied and the temperature is varied between about 815.degree. C. and about 835.degree. C. to produce not less than 80 percent conversion to Pb doped Bi-2223 superconducting phase and not greater than about 20 volume percent non-superconducting phases. The oxygen partial pressure is preferably varied between about 0.04 and about 0.21 atmospheres. A product by the method is disclosed.

  4. System and method for cooling a superconducting rotary machine

    DOE Patents [OSTI]

    Ackermann, Robert Adolf (Schenectady, NY); Laskaris, Evangelos Trifon (Schenectady, NY); Huang, Xianrui (Clifton Park, NY); Bray, James William (Niskayuna, NY)

    2011-08-09

    A system for cooling a superconducting rotary machine includes a plurality of sealed siphon tubes disposed in balanced locations around a rotor adjacent to a superconducting coil. Each of the sealed siphon tubes includes a tubular body and a heat transfer medium disposed in the tubular body that undergoes a phase change during operation of the machine to extract heat from the superconducting coil. A siphon heat exchanger is thermally coupled to the siphon tubes for extracting heat from the siphon tubes during operation of the machine.

  5. System and method for cooling a super-conducting device

    DOE Patents [OSTI]

    Bray, James William (Niskayuna, NY); Steinbach, Albert Eugene (Schenectady, NY); Dawson, Richard Nils (Voorheesville, NY); Laskaris, Evangelos Trifon (Schenectady, NY); Huang, Xianrul (Clifton Park, NY)

    2008-01-08

    A system and method for cooling a superconductive rotor coil. The system comprises a rotatable shaft coupled to the superconductive rotor coil. The rotatable shaft may comprise an axial passageway extending through the rotatable shaft and a first passageway extending through a wall of the rotatable shaft to the axial passageway. The axial passageway and the first passageway are operable to convey a cryogenic fluid to the superconductive rotor coil through the wall of the rotatable shaft. A cryogenic transfer coupling may be provided to supply cryogenic fluid to the first passageway.

  6. Solid state optical interconnect between distant superconducting quantum chips

    E-Print Network [OSTI]

    Keyu Xia; Jason Twamley

    2014-08-26

    We propose a design for a quantum interface exploiting the electron spins in crystals to swap the quantum states between the optical and microwave. Using sideband driving of a superconducting flux qubit and a combined cavity/solid-state spin ensemble Raman transition, we demonstrate how a stimulated Raman adiabatic passage (STIRAP)-type operation can swap the quantum state between a superconducting flux qubit and an optical cavity mode with a fidelity higher than $90\\%$. We further consider two distant superconducting qubits with their respective interfaces joined by an optical fiber and show a quantum transfer fidelity exceeding $90\\%$ between the two distant qubits.

  7. Silver-bearing, high-temperature, superconducting (HTS) paint

    SciTech Connect (OSTI)

    Ferrando, W.A.

    1990-02-15

    A substantial set of device applications awaits development of a workable, durable, high-temperature superconducting (HTS) paint. Such a paint should be truly superconducting with its critical temperature T sub c>77K. For most of these applications, a high critical current (J sub c) is not required, although probably desirable. A process is described which can be used to produce silver-bearing HTS paint coatings on many engineering materials. Preliminary tests have shown good adherence to several ceramics and the ability to meet the superconducting criteria. Moreover, the coatings withstand multiple thermal cycling and stability under laboratory ambient storage conditions for periods of at least several months.

  8. Superconductive silicon nanowires using gallium beam lithography.

    SciTech Connect (OSTI)

    Henry, Michael David; Jarecki, Robert Leo,

    2014-01-01

    This work was an early career LDRD investigating the idea of using a focused ion beam (FIB) to implant Ga into silicon to create embedded nanowires and/or fully suspended nanowires. The embedded Ga nanowires demonstrated electrical resistivity of 5 m-cm, conductivity down to 4 K, and acts as an Ohmic silicon contact. The suspended nanowires achieved dimensions down to 20 nm x 30 nm x 10 m with large sensitivity to pressure. These structures then performed well as Pirani gauges. Sputtered niobium was also developed in this research for use as a superconductive coating on the nanowire. Oxidation characteristics of Nb were detailed and a technique to place the Nb under tensile stress resulted in the Nb resisting bulk atmospheric oxidation for up to years.

  9. Competition between superconductivity and spin density wave

    E-Print Network [OSTI]

    Tian De Cao

    2012-08-25

    The Hubbard model has been investigated widely by many authors, while this work may be new in two aspects. One, we focus on the possible effects of the positions of the gaps associated with the pairing and the spin density wave. Two, we suggest that the models with different parameters are appropriate for different materials (or a material in different doped regions). This will lead to some new insights into the high temperature superconductors. It is shown that the SDW can appear at some temperature region when the on-site Coulomb interaction is larger, while the SC requires a decreased U at a lower temperature. This can qualitatively explain the relationship between superconducting and pseudogap states of Cu-based superconductors in underdoped and optimally doped regions. The superinsulator is also discussed.

  10. Ginzburg-Landau Approach to Holographic Superconductivity

    E-Print Network [OSTI]

    Aldo Dector

    2014-12-01

    We construct a family of minimal phenomenological models for holographic superconductors in d=4+1 AdS spacetime and study the effect of scalar and gauge field fluctuations. By making a Ginzburg-Landau interpretation of the dual field theory, we determine through holographic techniques a phenomenological Ginzburg-Landau Lagrangian and the temperature dependence of physical quantities in the superconducting phase. We obtain insight on the behaviour of the Ginzburg-Landau parameter and whether the systems behaves as a Type I or Type II superconductor. Finally, we apply a constant external magnetic field in a perturbative approach following previous work by D'Hoker and Kraus, and obtain droplet solutions which signal the appearance of the Meissner effect.

  11. Light superconducting strings in the Galaxy

    E-Print Network [OSTI]

    Francesc Ferrer; Tanmay Vachaspati

    2006-08-08

    Observations of the Milky Way by the SPI/INTEGRAL satellite have confirmed the presence of a strong 511 KeV gamma-ray line emission from the bulge, which require an intense source of positrons in the galactic center. These observations are hard to account for by conventional astrophysical scenarios, whereas other proposals, such as light DM, face stringent constraints from the diffuse gamma-ray background. Here we suggest that light superconducting strings could be the source of the observed 511 KeV emission. The associated particle physics, at the ~ 1 TeV scale, is within reach of planned accelerator experiments, while the distinguishing spatial distribution, proportional to the galactic magnetic field, could be mapped by SPI or by future, more sensitive, satellite missions.

  12. Method of preparing composite superconducting wire

    DOE Patents [OSTI]

    Verhoeven, John D. (Ames, IA); Gibson, Edwin D. (Ames, IA); Finnemore, Douglas K. (Ames, IA); Ostenson, Jerome E. (Ames, IA); Schmidt, Frederick A. (Ames, IA); Owen, Charles V. (Ames, IA)

    1985-08-06

    An improved method of preparing composite multifilament superconducting wire of Nb.sub.3 Sn in a copper matrix which eliminates the necessity of coating the drawn wire with tin. A generalized cylindrical billet of an alloy of copper containing at least 15 weight percent niobium, present in the copper as discrete, randomly distributed and oriented dendritic-shaped particles, is provided with at least one longitudinal opening which is filled with tin to form a composite drawing rod. The drawing rod is then drawn to form a ductile composite multifilament wire containing a filament of tin. The ductile wire containing the tin can then be wound into magnet coils or other devices before heating to diffuse the tin through the wire to react with the niobium forming Nb.sub.3 Sn. Also described is an improved method for making large billets of the copper-niobium alloy by consumable-arc casting.

  13. The Lichnerowicz-Weitzenboeck formula and superconductivity

    SciTech Connect (OSTI)

    Vargas-Paredes, Alfredo A.; Doria, Mauro M. [Departamento de Fisica dos Solidos, Universidade Federal do Rio de Janeiro, 21941-972 Rio de Janeiro (Brazil)] [Departamento de Fisica dos Solidos, Universidade Federal do Rio de Janeiro, 21941-972 Rio de Janeiro (Brazil); Neto, Jose Abdala Helayeel [Centro Brasileiro de Pesquisas Fisicas, 22290-160 Rio de Janeiro RJ (Brazil)] [Centro Brasileiro de Pesquisas Fisicas, 22290-160 Rio de Janeiro RJ (Brazil)

    2013-01-15

    We derive the Lichnerowicz-Weitzenboeck formula for the two-component order parameter superconductor, which provides a twofold view of the kinetic energy of the superconductor. For the one component order parameter superconductor we review the connection between the Lichnerowicz-Weitzenboeck formula and the Ginzburg-Landau theory. For the two-component case we claim that this formula opens a venue to describe inhomogeneous superconducting states intertwined by spin correlations and charged dislocation. In this case the Lichnerowicz-Weitzenboeck formula displays local rotational and electromagnetic gauge symmetry (SU(2) Circled-Times U(1)) and relies on local commuting momentum and spin operators. The order parameter lives in a space with curvature and torsion described by Elie Cartan geometrical formalism. The Lichnerowickz-Weitzenboeck formula leads to first order differential equations that are a three-dimensional version of the Seiberg-Witten equations.

  14. Critical magnetic field of surface superconductivity in lead

    SciTech Connect (OSTI)

    Khlyustikov, I. N., E-mail: khly@kapitza.ras.ru [Russian Academy of Sciences, Kapitza Institute of Physical Problems (Russian Federation)

    2011-12-15

    The critical superconductivity field H{sub c3} is measured on lead single crystals. It is shown that the temperature dependence of H{sub c3}/H{sub c} in the vicinity of superconducting transition temperature T{sub c} is essentially nonlinear. Relative changes in the value of H{sub c3}/H{sub c} reach approximately 30%, which cannot be described by the Ginzburg-Landau theory. The experimental temperature dependences lead to the conclusion that the surface superconducting transition temperature noticeably exceeds the superconducting transition temperature in the bulk of the semiconductor. The differences in the critical temperatures and in the Ginzburg-Landau parameters for lead are estimated.

  15. Electrothermal feedback in superconducting nanowire single-photon detectors

    E-Print Network [OSTI]

    Kerman, Andrew J.

    We investigate the role of electrothermal feedback in the operation of superconducting nanowire single-photon detectors (SNSPDs). It is found that the desired mode of operation for SNSPDs is only achieved if this feedback ...

  16. Geometry-dependent critical currents in superconducting nanocircuits

    E-Print Network [OSTI]

    Clem, John R.

    In this paper, we calculate the critical currents in thin superconducting strips with sharp right-angle turns, 180? turnarounds, and more complicated geometries, where all the line widths are much smaller than the Pearl ...

  17. Membrane-integrated superconducting nanowire single-photon detectors

    E-Print Network [OSTI]

    Najafi, Faraz

    We integrated superconducting nanowire single-photon detectors on sub-400-nm-thick silicon nitride membranes, which can then be transferred and aligned to photonic structures on a secondary chip with sub-micron placement accuracy.

  18. Afterpulsing and instability in superconducting nanowire avalanche photodetectors

    E-Print Network [OSTI]

    Marsili, Francesco

    We investigated the reset time of superconducting nanowire avalanche photodetectors (SNAPs) based on 30?nm wide nanowires. We studied the dependence of the reset time of SNAPs on the device inductance and discovered that ...

  19. Efficiently Coupling Light to Superconducting Nanowire Single-Photon Detectors

    E-Print Network [OSTI]

    Hu, Xiaolong

    We designed superconducting nanowire single-photon detectors (SNSPDs) integrated with silver optical antennae for free-space coupling and a dielectric waveguide for fiber coupling. According to our finite-element simulation, ...

  20. Superconducting-nanowire single-photon-detector linear array

    E-Print Network [OSTI]

    Zhao, Qingyuan

    We designed, fabricated, and tested a one-dimensional array of superconducting-nanowire single-photon detectors, integrated with on-chip inductors and resistors. The architecture is suitable for monolithic integration on ...

  1. Spontaneous vortex phase and pinning in ferromagnetic-superconducting systems 

    E-Print Network [OSTI]

    Kayali, Mohammad Amin

    2004-09-30

    of vortices is possible mostly in a close vicinity of the superconducting transition temperature Ts. For every case, the threshold value of the magnetization at which vortices start to be spontaneously created in the SC is calculated as a function...

  2. Strain-induced time-reversal odd superconductivity in graphene

    E-Print Network [OSTI]

    Bitan Roy; Vladimir Juricic

    2014-07-31

    Time-reversal symmetry breaking superconductors are exotic phases of matter with fascinating properties, which are, however, encountered rather sparsely. Here we identify the possibility of realizing such a superconducting ground state that exhibits an $f+is$ pairing symmetry in strained graphene. Although the underlying attractive interactions need to be sufficiently strong and comparable in pristine graphene to support such pairing state, we argue that strain can be conducive for its formation even for weak interactions. We show that quantum-critical behavior near the transition is controlled by a multicritical point, characterized by various critical exponents computed here in the framework of an $\\epsilon$-expansion near four spacetime dimensions. Furthermore, a vortex in this mixed superconducting state hosts a pair of Majorana fermions supporting a quartet of insulating and superconducting orders, among which topologically nontrivial quantum spin Hall insulator. These findings suggest that strained graphene could provide a platform for the realization of exotic superconducting states of Dirac fermions.

  3. Coherence characterization with a superconducting flux qubit through NMR approaches

    E-Print Network [OSTI]

    Yan, Fei, Ph. D. Massachusetts Institute of Technology

    2013-01-01

    This thesis discusses a series of experimental studies that investigate the coherence properties of a superconducting persistent-current or flux qubit, a promising candidate for developing a scalable quantum processor. A ...

  4. Spontaneous brillouin scattering quench diagnostics for large superconducting magnets

    E-Print Network [OSTI]

    Mahar, Scott B

    2008-01-01

    Large superconducting magnets used in fusion reactors, as well as other applications, need a diagnostic that can non-invasively measure the temperature and strain throughout the magnet in real-time. A new fiber optic sensor ...

  5. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Hlobil, Patrik

    2015-01-01

    We investigate a semiconductor $p$-$n$ junction in contact with superconducting leads that is operated under forward bias as a light-emitting diode. The presence of superconductivity results in a significant increase of the electroluminescence in a certain frequency window. We demonstrate that the tunneling of Cooper pairs induces an additional luminescence peak on resonance. There is a transfer of superconducting to photonic coherence which results in the emission of entangled photon pairs and squeezing of the fluctuations in the quadrature amplitudes of the emitted light. The squeezing angle can be electrically manipulated by changing the relative phase of the order parameters in the superconductors. We finally derive the conditions for lasing in the system and show that the laser threshold is reduced due to superconductivity. This shows how macroscopic coherence of a superconductor can be used to control the properties of light.

  6. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Patrik Hlobil; Peter P. Orth

    2015-05-11

    We investigate a semiconductor $p$-$n$ junction in contact with superconducting leads that is operated under forward bias as a light-emitting diode. The presence of superconductivity results in a significant increase of the electroluminescence in a certain frequency window. We demonstrate that the tunneling of Cooper pairs induces an additional luminescence peak on resonance. There is a transfer of superconducting to photonic coherence which results in the emission of entangled photon pairs and squeezing of the fluctuations in the quadrature amplitudes of the emitted light. The squeezing angle can be electrically manipulated by changing the relative phase of the order parameters in the superconductors. We finally derive the conditions for lasing in the system and show that the laser threshold is reduced due to superconductivity. This shows how macroscopic coherence of a superconductor can be used to control the properties of light.

  7. Inhomogeneous color superconductivity and the cooling of compact stars

    E-Print Network [OSTI]

    M. Ruggieri

    2007-04-13

    In this talk I discuss the inhomogeneous (LOFF) color superconductive phases of Quantum Chromodynamics (QCD). In particular, I show the effect of a core of LOFF phase on the cooling of a compact star.

  8. Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity

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

    character of the excitation spectrum is generally assumed to be linked to the "d-wave" symmetry of the superconducting state. In the high-Tc cuprates, this dichotomous gap...

  9. Radiofrequency amplifier based on a dc superconducting quantum interference device

    DOE Patents [OSTI]

    Hilbert, C.; Martinis, J.M.; Clarke, J.

    1984-04-27

    A low noise radiofrequency amplifer, using a dc SQUID (superconducting quantum interference device) as the input amplifying element. The dc SQUID and an input coil are maintained at superconductivity temperatures in a superconducting shield, with the input coil inductively coupled to the superconducting ring of the dc SQUID. A radiofrequency signal from outside the shield is applied to the input coil, and an amplified radiofrequency signal is developed across the dc SQUID ring and transmitted to exteriorly of the shield. A power gain of 19.5 +- 0.5 dB has been achieved with a noise temperature of 1.0 +- 0.4 K at a frequency of 100 MHz.

  10. Interlayer Coherence and Superconducting Condensate in the c...

    Office of Scientific and Technical Information (OSTI)

    Interlayer Coherence and Superconducting Condensate in the c-Axis Response of Optimally Doped Ba(Fe1-xCox)2As2 High-Tc Superconductor Using Infrared Spectroscopy Citation Details...

  11. Rhetorical strategies in the campaign for the Superconducting Super Collider 

    E-Print Network [OSTI]

    Taylor, Karen Michelle

    1996-01-01

    The campaign supporting the development and construction of the Superconducting Super Collider provides opportunities to further investigate the rhetoric of science as it borders on political rhetoric. Aristotelian rhetorical theory is used....

  12. Superfluid helium cryogenic systems for superconducting RF cavities...

    Office of Scientific and Technical Information (OSTI)

    (STF) for R and D of the International Linear Collider (ILC) project and the compact Energy Recovery Linac (cERL), employ superconducting RF cavities made of pure niobium,...

  13. Characterization of Nb?Sn superconducting strand under pure bending

    E-Print Network [OSTI]

    Harris, David L., S.M. Massachusetts Institute of Technology

    2005-01-01

    Characterizing the strain-dependent behavior of technological Nb?Sn superconducting strand has been an important subject of research for the past 25 years. Most of the effort has focused on understanding the uniaxial tension ...

  14. Superconducting generators for large off shore wind turbines 

    E-Print Network [OSTI]

    Keysan, Ozan

    2014-06-30

    This thesis describes four novel superconducting machine concepts, in the pursuit of finding a suitable design for large offshore wind turbines. The designs should be reliable, modular and light-weight. The main novelty ...

  15. Levitation pressure and friction losses in superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (Downers Grove, IL)

    2001-01-01

    A superconducting bearing having at least one permanent magnet magnetized with a vertical polarization. The lower or stator portion of the bearing includes an array of high-temperature superconducting elements which are comprised of a plurality of annular rings. An annular ring is located below each permanent magnet and an annular ring is offset horizontally from at least one of the permanent magnets. The rings are composed of individual high-temperature superconducting elements located circumferentially along the ring. By constructing the horizontally-offset high-temperature superconducting ring so that the c-axis is oriented in a radial direction, a higher levitation force can be achieved. Such an orientation will also provide substantially lower rotational drag losses in the bearing.

  16. Photoinduced changes of the chemical potential in superconducting...

    Office of Scientific and Technical Information (OSTI)

    Photoinduced changes of the chemical potential in superconducting Bi 2 Sr 2 CaCu 2 O 8 + Citation Details In-Document Search This content will become publicly available on...

  17. Electro-thermal simulation of superconducting nanowire avalanche photodetectors

    SciTech Connect (OSTI)

    Marsili, F.; Najafi, F.; Herder, C.; Berggren, K. K.

    2011-01-01

    We developed an electrothermal model of NbN superconducting nanowire avalanche photodetectors (SNAPs) on sapphire substrates. SNAPs are single-photon detectors consisting of the parallel connection of N superconducting nanowires. We extrapolated the physical constants of the model from experimental data and we simulated the time evolution of the device resistance, temperature and current by solving two coupled electrical and thermal differential equations describing the nanowires. The predictions of the model were in good quantitative agreement with the experimental results.

  18. Electro thermal simulation of superconducting nanowire avalanche photodetectors

    E-Print Network [OSTI]

    Francesco Marsili; Faraz Najafi; Charles Herder; Karl K. Berggren

    2010-12-17

    We developed an electro thermal model of NbN superconducting nanowire avalanche photodetectors (SNAPs) on sapphire substrates. SNAPs are single photon detectors consisting of the parallel connection of N superconducting nanowires. We extrapolated the physical constants of the model from experimental data and we simulated the time evolution of the device resistance, temperature and current by solving two coupled electrical and thermal differential equations describing the nanowires. The predictions of the model were in good quantitative agreement with the experimental results.

  19. A small-bore high-field superconducting quadrupole magnet

    SciTech Connect (OSTI)

    Barlow, D.B.; Kraus, R.H.; Lobb, C.T.; Menzel, M.T. ); Walstrom, P.L. )

    1990-01-01

    A prototype superconducting quadrupole magnet was designed and built for use in superconducting coupled-cavity linacs where the use of permanent magnets is ruled out by consideration of trapped flux losses. The magnet has a clear bore diameter of 1.8 cm and outside diameter of 11 cm and length of 11 cm. The magnet was operated at a temperature of 4.2 K and obtained a peak quadrupole field gradient of 320 T/m.

  20. Cooling of superconducting devices by liquid storage and refrigeration unit

    DOE Patents [OSTI]

    Laskaris, Evangelos Trifon; Urbahn, John Arthur; Steinbach, Albert Eugene

    2013-08-20

    A system is disclosed for cooling superconducting devices. The system includes a cryogen cooling system configured to be coupled to the superconducting device and to supply cryogen to the device. The system also includes a cryogen storage system configured to supply cryogen to the device. The system further includes flow control valving configured to selectively isolate the cryogen cooling system from the device, thereby directing a flow of cryogen to the device from the cryogen storage system.

  1. 2D barrier in a superconducting niobium square

    SciTech Connect (OSTI)

    Joya, Miryam R. Barba-ortega, J.; Sardella, Edson

    2014-11-05

    The presence of barriers changes the vortex structure in superconducting Nb square in presence of a uniform applied magnetic field. The Cooper pair configurations in a mesoscopics superconducting square of Nb with a barrier are calculated within the nonlinear Ginzburg Landau equations. We predict the nucleation of multi-vortex states into the sample and a soft entry of the magnetic field inside and around into the barrier. A novel and non-conventional vortex configurations occurs at determined magnetic field.

  2. Wire rope superconducting cable for diurnal load leveling SMES

    SciTech Connect (OSTI)

    Costello, G.A.

    1980-01-01

    The design of a wire rope cable for a superconducting magnetic energy storage (SMES) unit is discussed. The superconducting wires in the rope permit the passage of large currents in the relatively small conductors of the windings and hence cause large electromagnetic forces to act on the rope. The diameter of the rope, from a strength point of view, can be considerably reduced by supporting the rope at various points along its length.

  3. 7-forming, superconducting filaments through bicomponent dry spinning

    DOE Patents [OSTI]

    Tuominen, Olli P. (Ogden, UT); Morgan, Carol W. (Asheville, NC); Burlone, Dominick A. (Asheville, NC); Blankenship, Keith V. (Asheville, NC)

    2001-01-01

    Fibers which contain potentially superconducting material are dry spun by the steps of preparing a suspension of potentially superconducting powder in a thickened solvent; preparing a solution of fiber-forming polymer; supplying the suspension and the solution to a spinning apparatus; in the spinning apparatus, arranging the solution and the suspension in a bicomponent arrangement; extruding the arranged solution and suspension from a spinneret as a bicomponent filament; and removing the solvent from the filament.

  4. Road to room-temperature superconductivity: A universal model

    E-Print Network [OSTI]

    Manfred Bucher

    2013-03-11

    In a semiclassical view superconductivity is attributed exclusively to the advance of atoms' outer s electrons through the nuclei of neighbor atoms in a solid. The necessary progression of holes in the opposite direction has the electric and magnetic effect as if two electrons were advancing instead of each actual one. Superconductivity ceases when the associated lateral oscillation of the outer s electrons extends between neighbor atoms. If such overswing occurs already at T = 0, then the material is a normal conductor. Otherwise, lateral overswing can be caused by lattice vibrations at a critical temperature Tc or by a critical magnetic field Bc. Lateral electron oscillations are reduced - and Tc is increased - when the atoms of the outer s electrons are squeezed, be it in the bulk crystal, in a thin film, or under external pressure on the sample. The model is applied to alkali metals and alkali-doped fullerenes. Aluminum serves as an example of a simple metal with superconductivity. Application of the model to transition metals, intertransitional alloys and compounds of transition metals with other elements sheds light on the pattern of their critical temperature. More examples of the squeeze effect are provided by the superconductivity of PdH, MgB2, borocarbides, ferropnictides, and organic charge-transfer salts. The model also provides the superconduction mechanism in the oxide superconductors, exemplified by YBa2Cu3O7. Finally the model suggests which steps to take in order to reach superconductivity at room temperature and above.

  5. A Superconducting transformer system for high current cable testing

    SciTech Connect (OSTI)

    Godeke, A.; Dietderich, D. R.; Joseph, J. M.; Lizarazo, J.; Prestemon, S. O.; Miller, G.; Weijers, H. W.

    2010-02-15

    This article describes the development of a direct-current (dc) superconducting transformer system for the high current test of superconducting cables. The transformer consists of a core-free 10 464 turn primary solenoid which is enclosed by a 6.5 turn secondary. The transformer is designed to deliver a 50 kA dc secondary current at a dc primary current of about 50 A. The secondary current is measured inductively using two toroidal-wound Rogowski coils. The Rogowski coil signal is digitally integrated, resulting in a voltage signal that is proportional to the secondary current. This voltage signal is used to control the secondary current using a feedback loop which automatically compensates for resistive losses in the splices to the superconducting cable samples that are connected to the secondary. The system has been commissioned up to 28 kA secondary current. The reproducibility in the secondary current measurement is better than 0.05% for the relevant current range up to 25 kA. The drift in the secondary current, which results from drift in the digital integrator, is estimated to be below 0.5 A/min. The system's performance is further demonstrated through a voltage-current measurement on a superconducting cable sample at 11 T background magnetic field. The superconducting transformer system enables fast, high resolution, economic, and safe tests of the critical current of superconducting cable samples.

  6. IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 21, NO. 3, JUNE 2011 839 Integration of Optical Waveguides With Single

    E-Print Network [OSTI]

    Baba, Toshihiko

    IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 21, NO. 3, JUNE 2011 839 Integration, SFQ circuits, superconducting integrated circuits. I. INTRODUCTION THE performance of CMOS integrated [9]. Superconducting optoelectronic circuits that integrate both kinds of circuits have been

  7. Method and apparatus for connecting high voltage leads to a high temperature super-conducting transformer

    SciTech Connect (OSTI)

    Golner, Thomas M.; Mehta, Shirish P.

    2005-07-26

    A method and apparatus for connecting high voltage leads to a super-conducting transformer is provided that includes a first super-conducting coil set, a second super-conducting coil set, and a third super-conducting coil set. The first, second and third super-conducting coil sets are connected via an insulated interconnect system that includes insulated conductors and insulated connectors that are utilized to connect the first, second, and third super-conducting coil sets to the high voltage leads.

  8. INFLUENCE OF TOE ELECTRON-PHONON COUPLING ON SUPERCONDUCTING CONTACT AND THE PROPERTIES OF SUPERCONDUCTOR-SEMIMETAL (OR SEMICONDUCTOR) SYSTEMS

    E-Print Network [OSTI]

    Kresin, Vladimir Z.

    2012-01-01

    AND THE PROPERTIES OF SUPERCONDUCTQR-SEMIMETAL (OR SEMISchricffer, Theory of Superconductivity. W. Benjamin, Inc.McMillan, J. , Rowell, Superconductivity, vol. 1, Ed. R.

  9. LARGE SUPERCONDUCTING DETECTOR MAGNETS WITH ULTRA THIN COILS FOR USE IN HIGH ENERGY ACCELERATORS AND STORAGE RINGS

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    and Construction of a SuperconductingAluminum Stabilized·LBL-53S0, Hay 1977. Superconducting Magnet," CLyogenicsthe development of thin superconductiog solenoid magnets for

  10. ENERGY DIVISION STATUS OF SUPERCONDUCTING POWER TRANSFORMER

    Office of Scientific and Technical Information (OSTI)

    Momvm, evert the very limited losses of existing transfmers represent a significant cost over the expected life of the transformer. The desire to reduce these losses in...

  11. Timing performance of 30-nm-wide superconducting nanowire avalanche photodetectors

    E-Print Network [OSTI]

    Najafi, Faraz

    We investigated the timing jitter of superconducting nanowire avalanche photodetectors (SNAPs, also referred to as cascade-switching superconducting single-photon detectors) based on 30-nm-wide nanowires. At bias currents ...

  12. Mechanical alignment of particles for use in fabricating superconducting and permanent magnetic materials

    DOE Patents [OSTI]

    Nellis, William J. (Berkeley, CA); Maple, M. Brian (Del Mar, CA)

    1992-01-01

    A method for mechanically aligning oriented superconducting or permanently magnetic materials for further processing into constructs. This pretreatment optimizes the final crystallographic orientation and, thus, properties in these constructs. Such materials as superconducting fibers, needles and platelets are utilized.

  13. Growth and characterization of superconducting spinel oxide LiTi2O4 thin films

    E-Print Network [OSTI]

    Chopdekar, R.V.

    2009-01-01

    2004). [37] F. Gomory, Superconductor Science and TechnologyHabermeier, Journal of Superconductivity 13, 871 (2000). [SrTiO 3?? and LTO both superconduct and both have mixed-

  14. 1012 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 19, NO. 3, JUNE 2009 Microwave Packaging for Voltage

    E-Print Network [OSTI]

    Popovic, Zoya

    of circuits based upon superconductor-normal metal-superconductor (SNS) Josephson junction (JJ) technology1012 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 19, NO. 3, JUNE 2009 Microwave Packaging, Josephson device packaging, supercon- ducting device packaging, superconducting integrated circuits

  15. Abrupt onset of a second energy gap at the superconducting transition of underdoped Bi2212

    E-Print Network [OSTI]

    Lee, W.S.

    2008-01-01

    a sudden onset ofthe superconductinggap at Ts near the nodethEt the extrapolated superconduct- ing gap at the antinodethe rlodal region or the superconduct- ing condensate;thus,

  16. Volume 120, number 7 PHYSICSLETFERSA 9 March 1987 PHENOMENOLOGICALMODEL OF SUPERCONDUCTIVITY IN U

    E-Print Network [OSTI]

    Svozil, Karl

    Volume 120, number 7 PHYSICSLETFERSA 9 March 1987 PHENOMENOLOGICALMODEL OF SUPERCONDUCTIVITY IN U 1 1987 A phenomenological model taking into account the interaction between superconductivity superconductors (HSF) nonmagnetic impurity results inthe formation of an indicate that both compounds can

  17. PUBLISHED ONLINE: 29 JUNE 2014 | DOI: 10.1038/NPHYS3008 Dissipative superconducting state of

    E-Print Network [OSTI]

    Loss, Daniel

    : superconducting nanowires with super- conducting leads. We provide evidence that in such systems, normal current machines to Large Hadron Collider magnets. But is it indeed the case that superconducting order

  18. Excitation Fields in a Superconducting Global String

    E-Print Network [OSTI]

    J. R. Morris

    1995-09-28

    A model of a straight superconducting global cosmic string is examined in a setting wherein the string supports a charge/current pulse described by a travelling wave along the string. Linearized field equations are obtained for fluctuations of the scalar and vector fields of the theory, and a set of approximate particular solutions are found for the case in which the linear charge density and the current of the string have equal magnitudes. Although the equations of motion seem to suggest that the scalar and vector excitation fields are massive inside the string core, the particular solutions show that they behave as effectively massless fields which propagate at the speed of light along the string along with the primary charge/current pulse. The effect of the mass parameter is to modulate the radial profile of the excitation fields. The vector excitation field generates radial and angular components for both the electric and magnetic fields, but the particular solutions do not describe the emission or absorption of electromagnetic radiation from the string.

  19. Method of constructing a superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1981-01-01

    A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

  20. TOWARDS FAST-PULSED SUPERCONDUCTING SYNCHROTRON MAGNETS.

    SciTech Connect (OSTI)

    MORITZ,G.; MUEHLE,C.; ANERELLA,M.; GHOSH,A.; SAMPSON,W.; WANDERER,P.; WILLEN,E.; AGAPOV,N.; KHODZHIBAGIYAN,H.; KOVALENKO,A.; HASSENZAHL,W.V.; WILSON,M.N.

    2001-06-18

    The concept for the new GSI accelerator facilities is based on a large synchrotron designed for operation at BR=200 Tm and with the short cycle-time of about one second to achieve high average beam intensities. Superconducting magnets may reduce considerably investment and operating costs in comparison with conventional magnets. A R and D program was initiated to develop these magnets for a maximum field of 2-4 Tesla and a ramp rate of 4 T/s. In collaboration with JINR (Dubna), the window-frame type Nuclotron dipole, which has been operated with 4 T/s at a maximum field of 2 Tesla, shall be developed to reduce heat losses and to improve the magnetic field quality. Another collaboration with BNL (Brookhaven) was established to develop the one-layer-coil cos{theta}-type RHIC arc dipole designed for operation at 3.5 Tesla with a rather slow ramp-rate of 0.07 T/s towards the design ramp-rate of 4 T/s. The design concepts for both R and D programs are reported.

  1. Superconductivity for Large Scale Wind Turbines

    SciTech Connect (OSTI)

    R. Fair; W. Stautner; M. Douglass; R. Rajput-Ghoshal; M. Moscinski; P. Riley; D. Wagner; J. Kim; S. Hou; F. Lopez; K. Haran; J. Bray; T. Laskaris; J. Rochford; R. Duckworth

    2012-10-12

    A conceptual design has been completed for a 10MW superconducting direct drive wind turbine generator employing low temperature superconductors for the field winding. Key technology building blocks from the GE Wind and GE Healthcare businesses have been transferred across to the design of this concept machine. Wherever possible, conventional technology and production techniques have been used in order to support the case for commercialization of such a machine. Appendices A and B provide further details of the layout of the machine and the complete specification table for the concept design. Phase 1 of the program has allowed us to understand the trade-offs between the various sub-systems of such a generator and its integration with a wind turbine. A Failure Modes and Effects Analysis (FMEA) and a Technology Readiness Level (TRL) analysis have been completed resulting in the identification of high risk components within the design. The design has been analyzed from a commercial and economic point of view and Cost of Energy (COE) calculations have been carried out with the potential to reduce COE by up to 18% when compared with a permanent magnet direct drive 5MW baseline machine, resulting in a potential COE of 0.075 $/kWh. Finally, a top-level commercialization plan has been proposed to enable this technology to be transitioned to full volume production. The main body of this report will present the design processes employed and the main findings and conclusions.

  2. Cryostat design for the Superconducting Super Collider

    SciTech Connect (OSTI)

    Nicol, T.H.

    1990-09-01

    The cryostat of an SSC dipole magnet consists of all magnet components except the cold mass assembly. It serves to support the cold mass accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations and must be manufacturable at low cost. The major components of the cryostat are the vacuum vessel, thermal shields, multilayer insulation (MLI) system, cryogenic piping, interconnections, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course their 25 year expected life. This paper describes the design of the current SSC collider dipole magnet cryostat and includes discussions on the thermal, structural, and dynamic considerations involved in the development of each of the major systems. 7 refs., 4 figs.

  3. Phase Structure and Instability Problem in Color Superconductivity

    E-Print Network [OSTI]

    Kenji Fukushima

    2005-10-22

    We address the phase structure of color superconducting quark matter at high quark density. Under the electric and color neutrality conditions there appear various phases as a result of the Fermi surface mismatch among different quark flavors induced by finite strange quark mass; the color-flavor locked (CFL) phase where quarks are all energy gapped, the u-quark superconducting (uSC) phase where u-quarks are paired with either d- or s-quarks, the d-quark superconducting (dSC) phase that is the d-quark analogue of the uSC phase, the two-flavor superconducting (2SC) phase where u- and d-quarks are paired, and the unpaired quark matter (UQM) that is normal quark matter without pairing. Besides these possibilities, when the Fermi surface mismatch is large enough to surpass the gap energy, the gapless superconducting phases are expected. We focus our discussion on the chromomagnetic instability problem related to the gapless CFL (gCFL) onset and explore the instability regions on the phase diagram as a function of the temperature and the quark chemical potential. We sketch how to reach stable physical states inside the instability regions.

  4. Modified two-fluid model of conductivity for superconducting surface resistance calculation. Master's thesis

    SciTech Connect (OSTI)

    Linden, D.S.

    1993-05-01

    The traditional two-fluid model of superconducting conductivity was modified to make it accurate, while remaining fast, for designing and simulating microwave devices. The modification reflects the BCS coherence effects in the conductivity of a superconductor, and is incorporated through the ratio of normal to superconducting electrons. This modified ratio is a simple analytical expression which depends on frequency, temperature and material parameters. This modified two-fluid model allows accurate and rapid calculation of the microwave surface impedance of a superconductor in the clean and dirty limits and in the weak- and strong-coupled regimes. The model compares well with surface resistance data for Nb and provides insight into Nb3Sn and Y1Ba2Cu3O(7-delta). Numerical calculations with the modified two-fluid model are an order of magnitude faster than the quasi-classical program by Zimmermann (1), and two to five orders of magnitude faster than Halbritter's BCS program (2) for surface resistance.

  5. THE EFFECTS OF FILAMENT MAGNETIZATION IN SUPERCONDUCTING MAGNETS AS CALCULATED BY POISSION

    E-Print Network [OSTI]

    Caspi, S.

    2010-01-01

    29·0ctober 3, 1986 THE EFFECTS OF FILAMENT MAGNETIZATION IN244 THE EFFECTS OF FILAMENT MAGNETIZATION IN SUPERCONDUCTING

  6. UCSB final report for the CSQ program: Review of decoherence and materials physics for superconducting qubits

    E-Print Network [OSTI]

    Martinis, John M.

    for superconducting qubits John M. Martinis and A. Megrant University of California Santa Barbara (Dated: October 18, 2014) We review progress at UCSB on understanding the physics of decoherence in superconducting qubits report for a five-year program at IARPA on coherent superconducting qubits (CSQ). It summarizes our

  7. ENHANCEMENT OF SUPERCONDUCTING Tc IN Pd-H LIKE COMPOUNDS BY OPTICAL PHONONS

    E-Print Network [OSTI]

    Boyer, Edmond

    1227 ENHANCEMENT OF SUPERCONDUCTING Tc IN Pd-H LIKE COMPOUNDS BY OPTICAL PHONONS J. P. BURGER and D.450 1. Introduction. - The high superconducting tran- sition temperatures recently observed in Pd [1 interaction inhibiting superconductivity in pure Pd. As the density of states in Pd-H is rather similar [5

  8. Supplementary Information for "Rolling quantum dice with a superconducting qubit" R. Barends,1,

    E-Print Network [OSTI]

    Martinis, John M.

    Supplementary Information for "Rolling quantum dice with a superconducting qubit" R. Barends,1, J to this work. [1] Barends, R. et al. Superconducting quantum circuits at the surface code threshold for fault of a superconducting qubit. Phys. Rev. A 82, 042339 (2010). [4] Chow, J. M. et al. Implementing optimal control pulse

  9. ENHANCEMENT OF THE SUPERCONDUCTING TRANSITION TEMPERATURES IN ION-IMPLANTED ALUMINIUM ALLOYS (*)

    E-Print Network [OSTI]

    Boyer, Edmond

    L-287 ENHANCEMENT OF THE SUPERCONDUCTING TRANSITION TEMPERATURES IN ION-IMPLANTED ALUMINIUM ALLOYS helium temperatures, have maximum superconducting transition temperatures Tc of 4.2 K (C), 7.35 K (Ge 1976, Classification Physics Abstracts 7.188 - 8.362 One of the crucial problems in superconductivity

  10. Ferropnictide superconductors, i.e., superconductors that contain Fe and As, have superconducting transition

    E-Print Network [OSTI]

    Weston, Ken

    Ferropnictide superconductors, i.e., superconductors that contain Fe and As, have superconducting of these materials could not carry a large superconducting current because grain boundaries reduce the critical Hellstrom (DMR-Award 1006584) and Gregory S. Boebinger (DMR-Award 0654118) Applied Superconductivity Center

  11. BNL has always been a leader in the world of superconducting

    E-Print Network [OSTI]

    the Bulletin BNL has always been a leader in the world of superconducting magnets, which) (-452o Farenheit) become superconducting, that is, lose essentially all resistance to electricity superconducting at higher temperatures. These mate- rials can operate at the relatively high temperature of 77 K

  12. Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3

    E-Print Network [OSTI]

    Shen, Guoyin

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

  13. Superconductivity: The Meissner Effect, Persistent Currents and the Josephson MIT Department of Physics

    E-Print Network [OSTI]

    Seager, Sara

    to the superconducting state of several bulk samples of Type I and II superconductors is observed in measurementsSuperconductivity: The Meissner Effect, Persistent Currents and the Josephson Effects MIT Department of Physics (Dated: February 8, 2011) Several phenomena associated with superconductivity

  14. Quantum key distribution with high-speed superconducting single-photon detectors

    E-Print Network [OSTI]

    Quantum key distribution with high-speed superconducting single-photon detectors Robert H. Hadfield Abstract: We explore the potential of high-speed nanowire superconducting single-photon detectors, gating is essential to reduce the high dark count rate. Emerging superconducting detector technologies

  15. Analysis of measurement errors for a superconducting phase qubit Qin Zhang,1 Abraham G. Kofman,1,

    E-Print Network [OSTI]

    Martinis, John M.

    Analysis of measurement errors for a superconducting phase qubit Qin Zhang,1 Abraham G. Kofman,1 of a superconducting flux- biased phase qubit. Insufficiently long measurement pulse may lead to nonadiabatic- veloping superconducting Josephson-junction circuits for quantum computation. A wide variety

  16. State preservation by repetitive error detection in a superconducting quantum circuit J. Kelly,1,

    E-Print Network [OSTI]

    Martinis, John M.

    State preservation by repetitive error detection in a superconducting quantum circuit J. Kelly,1 , and superconducting circuits11­13 have demonstrated multi-qubit states that are first-order toler- ant to one type of error. Recently, experiments with ion traps and superconducting circuits have shown the simultaneous de

  17. Logic gates at the surface code threshold: Superconducting qubits poised for fault-tolerant quantum computing

    E-Print Network [OSTI]

    Martinis, John M.

    Logic gates at the surface code threshold: Superconducting qubits poised for fault-tolerant quantum circuits, and is compatible with microfabrication. For superconducting qubits the surface code7 99%. Here, we demonstrate a universal set of logic gates in a superconducting multi-qubit processor

  18. Analysis of a tunable coupler for superconducting phase qubits Ricardo A. Pinto and Alexander N. Korotkov*

    E-Print Network [OSTI]

    Martinis, John M.

    Analysis of a tunable coupler for superconducting phase qubits Ricardo A. Pinto and Alexander N a theoretical analysis of the recently realized tunable coupler for superconducting phase qubits R. C. Bialczak s : 03.67.Lx, 85.25.Cp I. INTRODUCTION Superconducting qubits1 are potential building blocks of a quantum

  19. Quantum state characterization of a fast tunable superconducting resonator Z. L. Wang,1

    E-Print Network [OSTI]

    Martinis, John M.

    Quantum state characterization of a fast tunable superconducting resonator Z. L. Wang,1 Y. P. Zhong-tunable superconducting coplanar waveguide resonator, with a tuning range of half a gigahertz and a switching time of 1 ns. The resonator is made tunable by inserting a superconducting quantum interference device in the center strip

  20. Supplementary Material for "Fabrication and Characterization of Aluminum Airbridges for Superconducting Microwave Circuits"

    E-Print Network [OSTI]

    Martinis, John M.

    for Superconducting Microwave Circuits" Zijun Chen,1 A. Megrant,1, 2 J. Kelly,1 R. Barends,1 J. Bochmann,1 Yu Chen,1 B and calculations, primarily for practical design considerations when building superconducting circuits using- able superconducting Josephson qubits built in an archi- tecture similar to the CPW resonators

  1. PHYSICAL REVIEW B 90, 144504 (2014) Compressed sensing quantum process tomography for superconducting quantum gates

    E-Print Network [OSTI]

    Martinis, John M.

    2014-01-01

    for superconducting quantum gates Andrey V. Rodionov,1 Andrzej Veitia,1 R. Barends,2 J. Kelly,2 Daniel Sank,2 J quantum gates based on superconducting Xmon and phase qubits. Using experimental data for a two and Monte Carlo process certification have been demonstrated experimentally for superconducting qubit gates

  2. Long coherence times for Rydberg qubits on a superconducting atom chip

    E-Print Network [OSTI]

    Vallette, Bruno

    Long coherence times for Rydberg qubits on a superconducting atom chip Physical Review A 90, 040502 on superconducting atom chip QuantumGDR 2014 1/17 #12;Introduction Introduction Poisson distribution ¯n 1 long data acquisition time Thanh Long NGUYEN (LKB) Rydberg atom on superconducting atom chip QuantumGDR 2014 2/17 CQED

  3. Accepted Manuscript Superconductivity in Entirely End-bonded Multi-Walled Carbon Nanotubes

    E-Print Network [OSTI]

    Maruyama, Shigeo

    Accepted Manuscript Superconductivity in Entirely End-bonded Multi-Walled Carbon Nanotubes I, Superconductivity in Entirely End-bonded Multi-Walled Carbon Nanotubes, Physica C (2007), doi: 10.1016/ j.physc.2007 disclaimers that apply to the journal pertain. #12;ACCEPTED MANUSCRIPT Physica C 1 Superconductivity

  4. Sputtered TiN films for superconducting coplanar waveguide resonators S. Ohya,1, a)

    E-Print Network [OSTI]

    Martinis, John M.

    Sputtered TiN films for superconducting coplanar waveguide resonators S. Ohya,1, a) B. Chiaro,2 A control the energy of these particles to obtain high-quality TiN films. Superconducting coplanar waveguideN in larger circuits. I. INTRODUCTION Superconducting coplanar-waveguide (SCPW) res- onators are used

  5. Superconductivity, nonadiabaticity and strong correlation in the light of recent experiments

    E-Print Network [OSTI]

    Cappelluti, Emmanuele

    Superconductivity, nonadiabaticity and strong correlation in the light of recent experiments L of information about the nature of the superconducting state, even thought many questions are still open. The Nonadiabatic Theory of Superconductivity represents a complex generalization of the ME theory which is natural

  6. High-Tc Superconductivity in Entirely End-bonded Multi-walled nanotubes

    E-Print Network [OSTI]

    Maruyama, Shigeo

    High-Tc Superconductivity in Entirely End-bonded Multi-walled nanotubes Junji Haruyama 1 , Izumi the emergence of superconductivity, such as Tomonaga-Luttinger liquid states and Peierls transition. Carbon nanotubes (CNs) are one of the best candidates for investigating the possibility of 1D superconductivity

  7. Superconductivity-induced phonon anomalies in high-Tc superconductors: A Raman intensity study

    E-Print Network [OSTI]

    Sipe,J. E.

    Superconductivity-induced phonon anomalies in high-Tc superconductors: A Raman intensity study O. V of a number of Raman-active phonons below the superconducting transition temperature in YBa2Cu3O7 x , Bi2Sr2Ca to obtain information about the superconducting state.4 Several years ago, Friedl et al.5 ob- served

  8. Hard superconducting nitrides Xiao-Jia Chen*, Viktor V. Struzhkin*, Zhigang Wu*, Maddury Somayazulu

    E-Print Network [OSTI]

    Wu, Zhigang

    Hard superconducting nitrides Xiao-Jia Chen*, Viktor V. Struzhkin*, Zhigang Wu*, Maddury Somayazulu, and hardness of selected superconducting transition-metal nitrides reveals inter- esting correlations among with the neutron scattering data. The cubic -NbN superconducting phase possesses a bulk modulus of 348 GPa

  9. Jorge Berger and Jacob Rubinstein On the zero set of the wave function in superconductivity

    E-Print Network [OSTI]

    Jorge Berger and Jacob Rubinstein On the zero set of the wave function in superconductivity October) model of superconductivity concerns an order parameter u which is a complex valued function of the absolute value of u measures the density of the superconducting electrons, while the phase of u is related

  10. PHYSICAL REVIEW A 87, 052306 (2013) Protected gates for superconducting qubits

    E-Print Network [OSTI]

    Preskill, John

    2013-01-01

    PHYSICAL REVIEW A 87, 052306 (2013) Protected gates for superconducting qubits Peter Brooks, Alexei the accuracy of quantum phase gates acting on "0- qubits" in superconducting circuits, where the gates superconducting circuits for this purpose. Specifically, several authors [3­5] have proposed designs

  11. Development of a cryogenic induction motor for use with a superconducting magnetic bearing

    E-Print Network [OSTI]

    Oxley, Paul

    Development of a cryogenic induction motor for use with a superconducting magnetic bearing Tomotake of a superconducting magnetic bearing (SMB). Both the motor and the SMB are operated at liquid He temperatures. We give Keywords: Astrophysical polarimeter; Induction motor; Superconducting magnetic bearings 1. Introduction

  12. Surface-resistance measurements using superconducting stripline resonators

    SciTech Connect (OSTI)

    Hafner, Daniel; Dressel, Martin; Scheffler, Marc, E-mail: scheffl@pi1.physik.uni-stuttgart.de [1. Physikalisches Institut, Universität Stuttgart, D-70550 Stuttgart (Germany)] [1. Physikalisches Institut, Universität Stuttgart, D-70550 Stuttgart (Germany)

    2014-01-15

    We present a method to measure the absolute surface resistance of conductive samples at a set of GHz frequencies with superconducting lead stripline resonators at temperatures 1–6 K. The stripline structure can easily be applied for bulk samples and allows direct calculation of the surface resistance without the requirement of additional calibration measurements or sample reference points. We further describe a correction method to reduce experimental background on high-Q resonance modes by exploiting TEM-properties of the external cabling. We then show applications of this method to the reference materials gold, tantalum, and tin, which include the anomalous skin effect and conventional superconductivity. Furthermore, we extract the complex optical conductivity for an all-lead stripline resonator to find a coherence peak and the superconducting gap of lead.

  13. Broadband sample holder for microwave spectroscopy of superconducting qubits

    SciTech Connect (OSTI)

    Averkin, A. S.; Karpov, A.; Glushkov, E.; Abramov, N. [National University of Science and Technology (MISIS), Leninskiy prosp. 4, Moscow, 119049 (Russian Federation); Shulga, K. [National University of Science and Technology (MISIS), Leninskiy prosp. 4, Moscow, 119049 (Russian Federation); Russian Quantum Center (RQC), 100 Novaya St., Skolkovo, Moscow region, 143025 (Russian Federation); Huebner, U. [Leibniz Institute of Photonic Technology (IPHT), PO Box 100239, D-07702 Jena (Germany); Il'ichev, E. [Russian Quantum Center (RQC), 100 Novaya St., Skolkovo, Moscow region, 143025 (Russian Federation); Leibniz Institute of Photonic Technology (IPHT), PO Box 100239, D-07702 Jena (Germany); Ustinov, A. V. [National University of Science and Technology (MISIS), Leninskiy prosp. 4, Moscow, 119049 (Russian Federation); Russian Quantum Center (RQC), 100 Novaya St., Skolkovo, Moscow region, 143025 (Russian Federation); Physikalisches Institut, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe (Germany)

    2014-10-15

    We present a practical design and implementation of a broadband sample holder suitable for microwave experiments with superconducting integrated circuits at millikelvin temperatures. Proposed design can be easily integrated in standard dilution cryostats, has flat pass band response in a frequency range from 0 to 32 GHz, allowing the RF testing of the samples with substrate size up to 4 × 4 mm{sup 2}. The parasitic higher modes interference in the holder structure is analyzed and prevented via design considerations. The developed setup can be used for characterization of superconducting parametric amplifiers, bolometers, and qubits. We tested the designed sample holder by characterizing of a superconducting flux qubit at 20 mK temperature.

  14. CLIQ. A new quench protection technology for superconducting magnets

    E-Print Network [OSTI]

    Ravaioli, Emmanuele; ten Kate, H H J

    CLIQ, the Coupling-Loss Induced Quench system, is a new method for protecting superconducting magnets after a sudden transition to the normal state. It offers significant advantages over the conventional technology due to its effective mechanism for heating the superconductor relying on coupling loss and its robust electrical design, which makes it more reliable and less interfering with the coil winding process. The analysis of the electro-magnetic and thermal transients during and after a CLIQ discharge allows identifying the system parameters that affect the system performance and defining guidelines for implementing this technology on coils of various characteristics. Most existing superconducting magnets can be protected by CLIQ as convincingly shown by test results performed on magnets of different sizes, superconductor types, geometries, cables and strand parameters. Experimental results are successfully reproduced by means of a novel technique for modeling non-linear dynamic effects in superconducting...

  15. Laboratory-Scale Superconducting Mirrors for Gravitational Microwaves

    E-Print Network [OSTI]

    Raymond Chiao; Stephen Minter; Kirk Wegter-McNelly

    2009-03-26

    When a gravitational wave at microwave frequencies impinges on a thin, type I superconducting film, the radical delocalization of the film's negatively charged Cooper pairs, which is due to the Uncertainty Principle, causes them to undergo non-geodesic motion relative to the geodesic motion of the decohered, positively charged ions in the film's lattice, which is due to the Equivalence Principle. The ensuing charge separation leads to a virtual plasma excitation. This "Heisenberg-Coulomb" effect enormously enhances the interaction of a gravitational wave with a superconductor relative to that of normal matter, so that the wave will be reflected even from a very thin superconducting film. This result is presented using the BCS theory and a superconducting plasma model.

  16. Controllable quantum information network with a superconducting system

    SciTech Connect (OSTI)

    Zhang, Feng-yang, E-mail: zhangfy@mail.dlut.edu.cn [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); Liu, Bao [Beijing Computational Science Research Center (CSRC), Beijing 100084 (China); Chen, Zi-hong [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Wu, Song-lin [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); Song, He-shan [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2014-07-15

    We propose a controllable and scalable architecture for quantum information processing using a superconducting system network, which is composed of current-biased Josephson junctions (CBJJs) as tunable couplers between the two superconducting transmission line resonators (TLRs), each coupling to multiple superconducting qubits (SQs). We explicitly demonstrate that the entangled state, the phase gate, and the information transfer between any two selected SQs can be implemented, respectively. Lastly, numerical simulation shows that our scheme is robust against the decoherence of the system. -- Highlights: •An architecture for quantum information processing is proposed. •The quantum information transfer between any two selected SQs is implemented. •This proposal is robust against the decoherence of the system. •This architecture can be fabricated on a chip down to the micrometer scale.

  17. Method for producing strain tolerant multifilamentary oxide superconducting wire

    DOE Patents [OSTI]

    Finnemore, D.K.; Miller, T.A.; Ostenson, J.E.; Schwartzkopf, L.A.; Sanders, S.C.

    1994-07-19

    A strain tolerant multifilamentary wire capable of carrying superconducting currents is provided comprising a plurality of discontinuous filaments formed from a high temperature superconducting material. The discontinuous filaments have a length at least several orders of magnitude greater than the filament diameter and are sufficiently strong while in an amorphous state to withstand compaction. A normal metal is interposed between and binds the discontinuous filaments to form a normal metal matrix capable of withstanding heat treatment for converting the filaments to a superconducting state. The geometry of the filaments within the normal metal matrix provides substantial filament-to-filament overlap, and the normal metal is sufficiently thin to allow supercurrent transfer between the overlapped discontinuous filaments but is also sufficiently thick to provide strain relief to the filaments. 6 figs.

  18. Method for producing strain tolerant multifilamentary oxide superconducting wire

    DOE Patents [OSTI]

    Finnemore, Douglas K. (Ames, IA); Miller, Theodore A. (Tucson, AZ); Ostenson, Jerome E. (Ames, IA); Schwartzkopf, Louis A. (Mankato, MN); Sanders, Steven C. (Ames, IA)

    1994-07-19

    A strain tolerant multifilamentary wire capable of carrying superconducting currents is provided comprising a plurality of discontinuous filaments formed from a high temperature superconducting material. The discontinuous filaments have a length at least several orders of magnitude greater than the filament diameter and are sufficiently strong while in an amorphous state to withstand compaction. A normal metal is interposed between and binds the discontinuous filaments to form a normal metal matrix capable of withstanding heat treatment for converting the filaments to a superconducting state. The geometry of the filaments within the normal metal matrix provides substantial filament-to-filament overlap, and the normal metal is sufficiently thin to allow supercurrent transfer between the overlapped discontinuous filaments but is also sufficiently thick to provide strain relief to the filaments.

  19. Structural analysis of superconducting dipole prototype for HIAF

    E-Print Network [OSTI]

    Zhang, Xiaoying; Ni, Dongsheng; Chen, Yuquan; Wu, Wei; Ma, Lizhen

    2015-01-01

    The High Intensity Heavy-Ion Accelerator Facility is a new project in the Institute of Modern Physics. The dipole magnets of all rings are conceived as fast cycled superconducting magnet with high magnetic field and large gap, the warm iron and superconducting coil structure (superferric) is adopted. The reasonable structure design of coil and cryostat is very important for reliable operation. Based on the finite element software ANSYS, the mechanical analysis of electromagnetic stress, the thermal stress in the cooling down and the stress in the pumping are showed in detail. According to the analysis result, the supporter structure is the key problem of coil system. With reasonable support's structure design, the stress and the deformation of coil structure can be reduced effectively, which ensure the stable operation of superconducting coil system.

  20. A new microphonics measurement method for superconducting RF cavities

    SciTech Connect (OSTI)

    Gao,Zheng; He,Yuan; Chang,Wei; Powers, Tom [JLAB; Yue,Wei-ming; Zhu,Zheng-long; Chen,Qi

    2014-09-01

    Mechanical vibrations of the superconducting cavity, also known as microphonics, cause shifts in the resonant frequency of the cavity. In addition to requiring additional RF power, these frequency shifts can contribute to errors in the closed loop phase and amplitude regulation. In order to better understand these effects, a new microphonics measurement method was developed, and the method was successfully used to measure microphonics on the half-wave superconducting cavity when it was operated in a production style cryostat. The test cryostat held a single ?=0.1 half-wave cavity which was operated at 162.5 MHz [1] and [2]. It's the first time that the National Instruments PXIe-5641R intermediate frequency transceiver has been used for microphonics measurements in superconducting cavities. The new microphonics measurement method and results will be shown and analyzed in this paper.

  1. Uniformly wound superconducting coil and method of making same

    DOE Patents [OSTI]

    Mookerjee, S.; Weijun, S.; Yager, B.

    1994-03-08

    A coil of superconducting wire for a superconducting magnet is described having a relatively dense and uniformly spaced winding to enhance the homogeneity and strength of the magnetic field surrounding the coil and a method of winding the same wherein the mandrel used to wind said coil comprises removable spacers and retainers forming a plurality of outwardly opening slots, each of said slots extending generally about the periphery of the mandrel and being sized to receive and outwardly align and retain successive turns of the superconducting wire within each slot as the wire is wound around and laterally across the mandrel to form a plurality of wire ribbons of a predetermined thickness laterally across the mandrel. 8 figures.

  2. Uniformly wound superconducting coil and method of making same

    DOE Patents [OSTI]

    Mookerjee, Sumit (Cedar Hill, TX); Weijun, Shen (Beijun, CN); Yager, Billy (Waxahachie, TX)

    1994-01-01

    A coil of superconducting wire for a superconducting magnet having a relaely dense and uniformly spaced winding to enhance the homogeneity and strength of the magnetic field surrounding the coil and a method of winding the same wherein the mandrel used to wind said coil comprises removable spacers and retainers forming a plurality of outwardly opening slots, each of said slots extending generally about the periphery of the mandrel and being sized to receive and outwardly align and retain successive turns of the superconducting wire within each slot as the wire is wound around and laterally across the mandrel to form a plurality of wire ribbons of a predetermined thickness laterally across the mandrel.

  3. High intensity neutrino source superconducting solenoid cyrostat design

    SciTech Connect (OSTI)

    Page, T.M.; Nicol, T.H.; Feher, S.; Terechkine, I.; Tompkins, J.; /Fermilab

    2006-06-01

    Fermi National Accelerator Laboratory (FNAL) is involved in the development of a 100 MeV superconducting linac. This linac is part of the High Intensity Neutrino Source (HINS) R&D Program. The initial beam acceleration in the front end section of the linac is achieved using room temperature spoke cavities, each of which is combined with a superconducting focusing solenoid. These solenoid magnets are cooled with liquid helium at 4.5K, operate at 250 A and have a maximum magnetic field strength of 7.5 T. The solenoid cryostat will house the helium vessel, suspension system, thermal shield, multilayer insulation, power leads, instrumentation, a vacuum vessel and cryogenic distribution lines. This paper discusses the requirements and detailed design of these superconducting solenoid cryostats.

  4. The LASS (Larger Aperture Superconducting Solenoid) spectrometer

    SciTech Connect (OSTI)

    Aston, D.; Awaji, N.; Barnett, B.; Bienz, T.; Bierce, R.; Bird, F.; Bird, L.; Blockus, D.; Carnegie, R.K.; Chien, C.Y.

    1986-04-01

    LASS is the acronym for the Large Aperture Superconducting Solenoid spectrometer which is located in an rf-separated hadron beam at the Stanford Linear Accelerator Center. This spectrometer was constructed in order to perform high statistics studies of multiparticle final states produced in hadron reactions. Such reactions are frequently characterized by events having complicated topologies and/or relatively high particle multiplicity. Their detailed study requires a spectrometer which can provide good resolution in momentum and position over almost the entire solid angle subtended by the production point. In addition, good final state particle identification must be available so that separation of the many kinematically-overlapping final states can be achieved. Precise analyses of the individual reaction channels require high statistics, so that the spectrometer must be capable of high data-taking rates in order that such samples can be acquired in a reasonable running time. Finally, the spectrometer must be complemented by a sophisticated off-line analysis package which efficiently finds tracks, recognizes and fits event topologies and correctly associates the available particle identification information. This, together with complicated programs which perform specific analysis tasks such as partial wave analysis, requires a great deal of software effort allied to a very large computing capacity. This paper describes the construction and performance of the LASS spectrometer, which is an attempt to realize the features just discussed. The configuration of the spectrometer corresponds to the data-taking on K and K interactions in hydrogen at 11 GeV/c which took place in 1981 and 1982. This constitutes a major upgrade of the configuration used to acquire lower statistics data on 11 GeV/c K p interactions during 1977 and 1978, which is also described briefly.

  5. Mechanical stabilization of BSCCO-2223 superconducting tapes

    SciTech Connect (OSTI)

    King, C.G.; Grey, D.A.; Mantone, A.

    1996-12-31

    A system to provide mechanical stabilization to high temperature BSCCO-2223 superconducting tape by laminating 0.081 mm thick, spring hard, copper foil to both sides with lead-tin eutectic solder has been successfully optimized. This system has been applied as a method to create a strong, windable composite from pure silver BSCCO tapes with a minimum of critical current (I{sub c}) degradation. The {open_quotes}as received{close_quotes} conductor is evaluated for physical consistency of width and thickness over the 3000 meters that were later strengthened, insulated and wound into a demonstration coil. Electrical degradation in the strengthened tape as a result of lamination was found to average 24 percent with a range from 4 to 51 percent. This was less than the degradation that would have occurred in an unstrengthened tape during subsequent insulation and coil winding processes. Additional work was performed to evaluate the mechanical properties of the strengthened tapes. The copper can double the ultimate tensile strength of the pure silver tapes. Additionally, pure silver and dispersion strengthened silver matrix tapes are laminated with 0.025 mm thick copper and 304 stainless steel foil to investigate minimization of the cross sectional area of the strengthening component. The stainless steel can increase the UTS of the pure silver tapes sixfold. Metallography is used to examine the laminate and the conductor. Mechanical properties and critical currents of these tapes are also reported both before and after strengthening. The I{sub c} is also measured as a function of strain on the laminated tapes.

  6. Full protection of superconducting qubit systems from coupling errors

    E-Print Network [OSTI]

    M. J. Storcz; J. Vala; K. R. Brown; J. Kempe; F. K. Wilhelm; K. B. Whaley

    2005-08-09

    Solid state qubits realized in superconducting circuits are potentially extremely scalable. However, strong decoherence may be transferred to the qubits by various elements of the circuits that couple individual qubits, particularly when coupling is implemented over long distances. We propose here an encoding that provides full protection against errors originating from these coupling elements, for a chain of superconducting qubits with a nearest neighbor anisotropic XY-interaction. The encoding is also seen to provide partial protection against errors deriving from general electronic noise.

  7. Non-Abelian Lattice Gauge Theories in Superconducting Circuits

    E-Print Network [OSTI]

    Mezzacapo, A; Sabín, C; Egusquiza, I L; Lamata, L; Solano, E

    2015-01-01

    We propose a digital quantum simulator of non-Abelian pure-gauge models with a superconducting circuit setup. Within the framework of quantum link models, we build a minimal instance of a pure $SU(2)$ gauge theory, using triangular plaquettes involving geometric frustration. This realization is the least demanding, in terms of quantum simulation resources, of a non-Abelian gauge dynamics. We present two superconducting architectures that can host the quantum simulation, estimating the requirements needed to run possible experiments. The proposal establishes a path to the experimental simulation of non-Abelian physics with solid-state quantum platforms.

  8. Support system design for a superconducting MRI magnet 

    E-Print Network [OSTI]

    Watts, Louis Chad

    1993-01-01

    . A design of a support system for a superconducting magnet was developed. This system will be used to suspend the Texas Accelerator Center (TAC) liquid helium cooled, four tesla, one meter bore, superconducting coils (cold mass) inside a room...-to-noise ratio is approximately proportional to the magnetic field'. TAC's magnet has a 4 tesla (T) field slrength for improved resolution compared to commercially available MRI magnets at 0. 5 to 2 T. The TAC magnet uses saturated iron to restrict the fringe...

  9. Ising interaction between capacitively-coupled superconducting flux qubits

    E-Print Network [OSTI]

    Takahiko Satoh; Yuichiro Matsuzaki; Kosuke Kakuyanagi; Koichi Semba; Hiroshi Yamaguchi; Shiro Saito

    2015-01-30

    Here, we propose a scheme to generate a controllable Ising interaction between superconducting flux qubits. Existing schemes rely on inducting couplings to realize Ising interactions between flux qubits, and the interaction strength is controlled by an applied magnetic field On the other hand, we have found a way to generate an interaction between the flux qubits via capacitive couplings. This has an advantage in individual addressability, because we can control the interaction strength by changing an applied voltage that can be easily localized. This is a crucial step toward the realizing superconducting flux qubit quantum computation.

  10. Buffer layers for REBCO films for use in superconducting devices

    SciTech Connect (OSTI)

    Goyal, Amit; Wee, Sung-Hun

    2014-06-10

    A superconducting article includes a substrate having a biaxially textured surface. A biaxially textured buffer layer, which can be a cap layer, is supported by the substrate. The buffer layer includes a double perovskite of the formula A.sub.2B'B''O.sub.6, where A is rare earth or alkaline earth metal and B' and B'' are different transition metal cations. A biaxially textured superconductor layer is deposited so as to be supported by the buffer layer. A method of making a superconducting article is also disclosed.

  11. Superconductivity in Metal-mixed Ion-Implanted Polymer Films

    E-Print Network [OSTI]

    A. P. Micolich; E. Tavenner; B. J. Powell; A. R. Hamilton; M. T. Curry; R. E. Giedd; P. Meredith

    2006-03-15

    Ion-implantation of normally insulating polymers offers an alternative to depositing conjugated organics onto plastic films to make electronic circuits. We used a 50 keV nitrogen ion beam to mix a thin 10 nm Sn/Sb alloy film into the sub-surface of polyetheretherketone (PEEK) and report the low temperature properties of this material. We observed metallic behavior, and the onset of superconductivity below 3 K. There are strong indications that the superconductivity does not result from a residual thin-film of alloy, but instead from a network of alloy grains coupled via a weakly conducting, ion-beam carbonized polymer matrix.

  12. Quantum tunneling, quantum computing, and high temperature superconductivity 

    E-Print Network [OSTI]

    Wang, Qian

    2005-02-17

    -1 QUANTUM TUNNELING, QUANTUM COMPUTING, AND HIGH TEMPERATURE SUPERCONDUCTIVITY A Dissertation by QIAN WANG Submitted to the O?ce of Graduate Studies of Texas A&M University in partial ful?llment of the requirements for the degree of DOCTOR OF PHILOSOPHY... December 2003 Major Subject: Physics QUANTUM TUNNELING, QUANTUM COMPUTING, AND HIGH TEMPERATURE SUPERCONDUCTIVITY A Dissertation by QIAN WANG Submitted to Texas A&M University in partial ful?llment of the requirements for the degree of DOCTOR OF PHILOSOPHY...

  13. Superconducting spoke cavities for high-velocity applications

    SciTech Connect (OSTI)

    Hopper, Christopher S. [Old Dominion U.; Delayen, Jean R. [Old Dominion U., JLAB

    2013-10-01

    To date, superconducting spoke cavities have been designed, developed, and tested for particle velocities up to {beta}{sub 0}~0.6, but there is a growing interest in possible applications of multispoke cavities for high-velocity applications. We have explored the design parameter space for low-frequency, high-velocity, double-spoke superconducting cavities in order to determine how each design parameter affects the electromagnetic properties, in particular the surface electromagnetic fields and the shunt impedance. We present detailed design for cavities operating at 325 and 352 MHz and optimized for {beta}{sub 0}~=0.82 and 1.

  14. Convergence of Ginzburg-Landau functionals in 3-d superconductivity

    E-Print Network [OSTI]

    Sisto Baldo; Robert L. Jerrard; Giandomenico Orlandi; Mete Soner

    2011-02-23

    In this paper we consider the asymptotic behavior of the Ginzburg- Landau model for superconductivity in 3-d, in various energy regimes. We rigorously derive, through an analysis via {\\Gamma}-convergence, a reduced model for the vortex density, and we deduce a curvature equation for the vortex lines. In a companion paper, we describe further applications to superconductivity and superfluidity, such as general expressions for the first critical magnetic field H_{c1}, and the critical angular velocity of rotating Bose-Einstein condensates.

  15. Toroidal constant-tension superconducting magnetic energy storage units

    DOE Patents [OSTI]

    Herring, J.S.

    1992-11-03

    A superconducting magnetic energy storage unit is provided in which the magnet is wound in a toroidal fashion such that the magnetic field produced is contained only within the bore of the magnet, and thus producing a very low external field. The superconducting magnet includes a coolant channel disposed through the wire. The bore of the magnet comprises a storage volume in which cryogenic coolant is stored, and this volume supplies the coolant to be delivered to the coolant channel in the magnet. 6 figs.

  16. Segmented superconducting tape having reduced AC losses and method of making

    DOE Patents [OSTI]

    Foltyn, Stephen R. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Arendt, Paul N. (Los Alamos, NM); Holesinger, Terry G. (Los Alamos, NM); Wang, Haiyan (Los Alamos, NM)

    2009-09-22

    A superconducting tape having reduced AC losses. The tape has a high temperature superconductor layer that is segmented. Disruptive strips, formed in one of the tape substrate, a buffer layer, and the superconducting layer create parallel discontinuities in the superconducting layer that separate the current-carrying elements of the superconducting layer into strips or filament-like structures. Segmentation of the current-carrying elements has the effect of reducing AC current losses. Methods of making such a superconducting tape and reducing AC losses in such tapes are also disclosed.

  17. Cryogenic Test of a 750 MHz Superconducting RF Dipole Crabbing Cavity

    SciTech Connect (OSTI)

    Castilla, Alejandro [ODU; Delayen, Jean R. [ODU, JLAB; Park, HyeKyoung [JLAB

    2014-07-01

    A superconducting rf dipole cavity has been designed to address the challenges of a high repetition rate (750 MHz), high current for both electron/ion species (0.5/3 A per bunch), and large crossing angle (50 mrad) at the interaction points (IPs) crabbing system for the Medium Energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab. The cavity prototype built at Niowave, Inc. has been tested at the Jefferson Lab facilities. In this work we present a detailed analysis of the prototype cavity performance at 4 K and 2 K, corroborating the absence of hard multipacting barriers that could limit the desired transverse fields, along with the surface resistance (Rs) temperature dependency.

  18. Ultimate low system dark count rate for superconducting nanowire single-photon detector

    E-Print Network [OSTI]

    Hiroyuki Shibata; Kaoru Shimizu; Hiroki Takesue; Yasuhiro Tokura

    2015-07-07

    The dark count rate (DCR) is a key parameter of single-photon detectors. By introducing a bulk optical band-pass filter mounted on a fiber-to-fiber optical bench cooled at 3 K and blocking down to 5 micrometer, we suppressed the DCR of a superconducting nanowire single-photon detector by more than three orders of magnitude. The DCR is limited by the blackbody radiation through a signal passband of 20 nm bandwidth. The figure of merit, system detection efficiency, and DCR were 2.7 x 10^11, 2.3 %, and 0.001 Hz, respectively. Narrowing the bandwidth to 100 GHz suppresses the DCR to 0.0001 Hz and the figure of merit increases to 1.8 x 10^12.

  19. Ultimate low system dark count rate for superconducting nanowire single-photon detector

    E-Print Network [OSTI]

    Shibata, Hiroyuki; Takesue, Hiroki; Tokura, Yasuhiro

    2015-01-01

    The dark count rate (DCR) is a key parameter of single-photon detectors. By introducing a bulk optical band-pass filter mounted on a fiber-to-fiber optical bench cooled at 3 K and blocking down to 5 micrometer, we suppressed the DCR of a superconducting nanowire single-photon detector by more than three orders of magnitude. The DCR is limited by the blackbody radiation through a signal passband of 20 nm bandwidth. The figure of merit, system detection efficiency, and DCR were 2.7 x 10^11, 2.3 %, and 0.001 Hz, respectively. Narrowing the bandwidth to 100 GHz suppresses the DCR to 0.0001 Hz and the figure of merit increases to 1.8 x 10^12.

  20. Superconducting articles of manufacture and method of producing same

    DOE Patents [OSTI]

    Newkirk, Lawrence R. (Los Alamos, NM); Valencia, Flavio A. (Santa Fe, NM)

    1980-01-01

    Bulk coatings of Nb.sub.3 Ge with high superconducting transition temperatures bonded to metallic substrates and a chemical vapor deposition method for producing such coatings on metallic substrates are disclosed. In accordance with the method, a Nb.sub.3 Ge coating having a transition temperature in excess of 21.5 K may be tightly bonded to a copper substrate.