Sample records for limiting superconducting transformer

  1. A Superconducting transformer system for high current cable testing

    E-Print Network [OSTI]

    Godeke, A.

    2010-01-01T23:59:59.000Z

    A Superconducting Transformer System for High Current Cablea Direct-Current (DC) superconducting transformer system forhigh current test of superconducting cables. The transformer

  2. A Superconducting transformer system for high current cable testing

    E-Print Network [OSTI]

    Godeke, A.

    2010-01-01T23:59:59.000Z

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

  3. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, J.R.

    1997-02-04T23:59:59.000Z

    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.

  4. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1997-01-01T23:59:59.000Z

    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).

  5. Self-triggering superconducting fault current limiter

    DOE Patents [OSTI]

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

    2008-10-21T23:59:59.000Z

    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.

  6. High-temperature superconducting transformer performance, cost, and market evaluation

    SciTech Connect (OSTI)

    Dirks, J.A.; Dagle, J.E.; DeSteese, J.G.; Huber, H.D.; Smith, S.A.; Currie, J.W. [Pacific Northwest Lab., Richland, WA (United States); Merrick, S.B. [Westinghouse Hanford Co., Richland, WA (United States); Williams, T.A. [National Renewable Energy Lab., Golden, CO (United States)

    1993-09-01T23:59:59.000Z

    Recent laboratory breakthroughs in high-temperature superconducting (HTS) materials have stimulated both the scientific community and general public with questions regarding how these materials can be used in practical applications. While there are obvious benefits from using HTS materials (most notably the potential for reduced energy losses in the conductors), a number of issues (such as overall system energy losses, cost, and reliability) may limit applications of HTS equipment, even if the well known materials problems are solved. This study examined the future application potential of HTS materials to power transformers. This study effort was part of a US Department of Energy (DOE) Office of Energy Storage and Distribution (OESD) research program, Superconductivity Technology for Electric Power Systems (STEPS). The study took a systems perspective to gain insights to help guide DOE in managing research designed to realize the vision of HTS applications. Specific objectives of the study were as follows: to develop an understanding of the fundamental HTS transformer design issues that can provide guidance for developing practical devices of interest to the electric utility industry; to identify electric utility requirements for HTS transformers and to evaluate the potential for developing a commercial market; to evaluate the market potential and national benefits for HTS transformers that could be achieved by a successful HTS development program; to develop an integrated systems analysis framework, which can be used to support R&D planning by DOE, by identifying how various HTS materials characteristics impact the performance, cost, and national benefits of the HTS application.

  7. Transformer current sensor for superconducting magnetic coils

    DOE Patents [OSTI]

    Shen, Stewart S. (Oak Ridge, TN); Wilson, C. Thomas (Norris, TN)

    1988-01-01T23:59:59.000Z

    A transformer current sensor having primary turns carrying a primary current for a superconducting coil and secondary turns only partially arranged within the primary turns. The secondary turns include an active winding disposed within the primary turns and a dummy winding which is not disposed in the primary turns and so does not experience a magnetic field due to a flow of current in the primary turns. The active and dummy windings are wound in opposite directions or connected in series-bucking relationship, and are exposed to the same ambient magnetic field. Voltages which might otherwise develop in the active and dummy windings due to ambient magnetic fields thus cancel out. The resultant voltage is purely indicative of the rate of change of current flowing in the primary turns.

  8. Self field triggered superconducting fault current limiter

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D. (Rexford, NY)

    2008-02-19T23:59:59.000Z

    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.

  9. 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.

    2010-02-15T23:59:59.000Z

    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.

  10. ENERGY DIVISION STATUS OF SUPERCONDUCTING POWER TRANSFORMER

    Office of Scientific and Technical Information (OSTI)

    is not presently a room t e m p e r a t u r e phenomenon. Hence, any superconducting system must be cooied and remain cooled below a critical temperature to functioo as a...

  11. Superconducting fault current-limiter with variable shunt impedance

    DOE Patents [OSTI]

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19T23:59:59.000Z

    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.

  12. Conductor requirements for high-temperature superconducting utility power transformers

    SciTech Connect (OSTI)

    Pleva, E. F. [Waukesha Electric Systems, Waukesha, WI; Mehrotra, V. [Waukesha Electric Systems, Waukesha, WI; Schwenterly, S W [ORNL

    2010-01-01T23:59:59.000Z

    High-temperature superconducting (HTS) coated conductors in utility power transformers must satisfy a set of operating requirements that are driven by two major considerations-HTS transformers must be economically competitive with conventional units, and the conductor must be robust enough to be used in a commercial manufacturing environment. The transformer design and manufacturing process will be described in order to highlight the various requirements that it imposes on the HTS conductor. Spreadsheet estimates of HTS transformer costs allow estimates of the conductor cost required for an HTS transformer to be competitive with a similarly performing conventional unit.

  13. Transformer current sensor for superconducting magnetic coils

    DOE Patents [OSTI]

    Shen, S.S.; Wilson, C.T.

    1985-04-16T23:59:59.000Z

    The present invention is a current transformer for operating currents larger than 2kA (two kiloamps) that is capable of detecting a millivolt level resistive voltage in the presence of a large inductive voltage. Specifically, the present invention includes substantially cylindrical primary turns arranged to carry a primary current and substantially cylindrical secondary turns arranged coaxially with and only partially within the primary turns, the secondary turns including an active winding and a dummy winding, the active and dummy windings being coaxial, longitudinally separated and arranged to mutually cancel voltages excited by commonly experienced magnetic fields, the active winding but not the dummy winding being arranged within the primary turns.

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

    SciTech Connect (OSTI)

    Golner, Thomas M.; Mehta, Shirish P.

    2005-07-26T23:59:59.000Z

    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.

  15. 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

  16. Investigation of Microscopic Materials Limitations of Superconducting RF Cavities

    SciTech Connect (OSTI)

    Anlage, Steven [University of Maryland

    2014-07-23T23:59:59.000Z

    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.

  17. Superconducting Materials and Conductors : Fabrication and Limiting Parameters

    E-Print Network [OSTI]

    Bottura, L

    2013-01-01T23:59:59.000Z

    Superconductivity is the technology that enabled the construction of the most recent generation of high-energy particle accelerators, the largest scientific instruments ever built. In this review we trace the evolution of superconducting materials for particle accelerator magnets, from the first steps in the late 1960s, through the rise and glory of Nb–Ti in the 1970s, till the 2010s, and the promises of Nb3Sn for the 2020s. We conclude with a perspective on the opportunities for high-temperature superconductors (HTSs). Many such reviews have been written in the past, as witnessed by the long list of references provided. In this review we put particular emphasis on the practical aspects of wire and tape manufacturing, cabling, engineering performance, and potential for use in accelerator magnets, while leaving in the background matters such as the physics of superconductivity and fundamental material issues.

  18. Superconducting phase qubits

    E-Print Network [OSTI]

    Martinis, John M.

    2009-01-01T23:59:59.000Z

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

  19. Superconducting phase qubits

    E-Print Network [OSTI]

    Martinis, John M.

    2009-01-01T23:59:59.000Z

    frequency noise in dc superconducting quantum interfer- enceTransformed dissipation in superconducting quantum circuits.two-level system noise in superconducting microreson- ators.

  20. Dynamics of a superconducting qubit coupled to the quantized cavity field: a unitary transformation approach

    E-Print Network [OSTI]

    Dagoberto S. Freitas; A. Vidiella-Barranco; J. A. Roversi

    2014-04-06T23:59:59.000Z

    We present a novel approach for studying the dynamics of a superconducting qubit in a cavity. We succeed in linearizing the Hamiltonian through the application of an appropriate unitary transformation followed by a rotating wave approximation (RWA). For certain values of the parameters involved, we show that it is possible to obtain a a Jaynes-Cummings type Hamiltonian. As an example, we show the existence of super-revivals for the qubit inversion.

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

    DOE Patents [OSTI]

    Yuan, Xing (Albany, NY)

    2008-04-15T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Johnson, Jedediah Edward Jensen

    2012-01-01T23:59:59.000Z

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

  3. Repetitive petawatt-class laser with near-diffraction-limited focal spot and transform-limited pulse duration

    E-Print Network [OSTI]

    Umstadter, Donald

    Repetitive petawatt-class laser with near-diffraction-limited focal spot and transform-loop feedback control systems in the temporal and spatial domains are used to yield Fourier-transform acceleration and x-ray generation. Keywords: petawatt, diffraction limited, transform limited, spatial

  4. Development of a large-capacity superconducting cable for 100 kVA-class power transformers

    SciTech Connect (OSTI)

    Funaki, K.; Iwakuma, M.; Satoh, S.; Hiramatsu, M.; Takeo, M.; Yamafuji, K.; Nonaka, S. (Kyushu Univ., Fukuoka (Japan). Faculty of Engineering); Hoshino, M.; Simada, M.; Yoneda, E.S. (Toshiba Corp., Yokohama (JP))

    1992-01-01T23:59:59.000Z

    This paper reports that the authors have designed and fabricated a large-capacity superconducting cable for 1000k VA-class power transformers. The cable is a triply-stacked multi-strand (6 {times} 6 {times} 6) type. The elementary strand has 19,050 NbTi filaments of 0.63 mm thick in CuNi matrix. The test cable is installed as the secondary winding in a superconducting transformer with iron core in a room-temperature space. The primary winding is the second-level subcable of the secondary one and the turn ratio is nearly 14. The designed capacity of the test cable is 4.545 kA at the secondary voltage of 220V. The peak value of the current, 6.43kA (peak), is 78% of the critical current on the load line. The maximum current of the cable at 60Hz operation was 3.78kA (peak). The attained level of the secondary winding is 47% of the critical current. In the 60Hz operation of a small coil wound by the test cable, premature quench was initiated from the terminals of the cable connected with copper plates. It is suggested from the experimental results that the degradation in maximum current of the test cable is related to current transfer between the cable and the copper terminal plates.

  5. Superconducting qubit as a quantum transformer routing entanglement between a microscopic quantum memory and a macroscopic resonator

    SciTech Connect (OSTI)

    Kemp, Alexander; Saito, Shiro; Semba, Kouichi [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya Atsugi-shi, Kanagawa 243-0198 (Japan); Munro, William J. [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya Atsugi-shi, Kanagawa 243-0198 (Japan); National Institute of Informatics 2-1-2 Hitotsubashi, Chiyoda ku, Tokyo 101-8430 (Japan); Nemoto, Kae [National Institute of Informatics 2-1-2 Hitotsubashi, Chiyoda ku, Tokyo 101-8430 (Japan)

    2011-09-01T23:59:59.000Z

    We demonstrate experimentally the creation and measurement of an entangled state between a microscopic two-level system (TLS), formed by a defect in an oxide layer, and a macroscopic superconducting resonator, where their indirect interaction is mediated by an artificial atom, a superconducting persistent current qubit (PCQB). Under appropriate conditions, we found the coherence time of the TLS, the resonator, and the entangled state of these two are significantly longer than the Ramsey dephasing time of PCQB itself. This demonstrates that a PCQB can be used as a quantum transformer to address high coherence microscopic quantum memories by connecting them to macroscopic quantum buses.

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

    SciTech Connect (OSTI)

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

    2005-04-13T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

    Boenig, H.J.

    1982-08-16T23:59:59.000Z

    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.

  8. Design, Fabrication and Testing of a Superconducting Fault Current Limiter (SFCL)

    SciTech Connect (OSTI)

    Gouge, M..; Schwenterly, S.W.; Hazelton, D. (SuperPower, Inc.)

    2011-06-15T23:59:59.000Z

    The purpose of this project was to conduct R&D on specified components and provide technical design support to a SuperPower team developing a high temperature superconducting Fault Current Limiter (SFCL). ORNL teamed with SuperPower, Inc. on a Superconductivity Partnerships with Industry (SPI) proposal for the SFCL that was submitted to DOE and approved in FY 2003. A contract between DOE and SuperPower, Inc. was signed on July 14, 2003 to design, fabricate and test the SFCL. This device employs high temperature superconducting (HTS) elements and SuperPower's proprietary technology. The program goal was to demonstrate a device that will address a broad range of the utility applications and meet utility industry requirements. This DOE-sponsored Superconductivity Partnership with Industry project would positively impact electric power transmission reliability and security by introducing a new element in the grid that can significantly mitigate fault currents and provide lower cost solutions for grid protection. The project will conduct R&D on specified components and provide technical design support to a SuperPower-led team developing a SFCL as detailed in tasks 1-5 below. Note the SuperPower scope over the broad SPI project is much larger than that shown below which indicates only the SuperPower tasks that are complementary to the ORNL tasks. SuperPower is the Project Manager for the SFCL program, and is responsible for completion of the project on schedule and budget. The scope of work for ORNL is to provide R&D support for the SFCL in the following four broad areas: (1) Assist with high voltage subsystem R&D, design, fabrication and testing including characterization of the general dielectric performance of LN2 and component materials; (2) Consult on cryogenic subsystem R&D, design, fabrication and testing; (3) Participate in project conceptual and detailed design reviews; and (4) Guide commercialization by participation on the Technical Advisory Board (TAB). SuperPower's in-kind work for the SFCL will be provided in the following areas: (1) Work with ORNL to develop suitable test platforms for the evaluation of subsystems and components; (2) Provide cryogenic and high voltage subsystem designs for evaluation; (3) Lead the development of the test plans associated with the subsystem and components and participate in test programs at ORNL; and (4) Based on the test results, finalize the subsystem and component designs and incorporate into the respective SFCL prototypes.

  9. Probing the fundamental limit of niobium in high radiofrequency fields by dual mode excitation in superconducting radiofrequency cavities

    SciTech Connect (OSTI)

    Eremeev, Grigory; Geng, Rongli; Palczewski, Ari

    2011-07-01T23:59:59.000Z

    We have studied thermal breakdown in several multicell superconducting radiofrequency cavity by simultaneous excitation of two TM{sub 010} passband modes. Unlike measurements done in the past, which indicated a clear thermal nature of the breakdown, our measurements present a more complex picture with interplay of both thermal and magnetic effects. JLab LG-1 that we studied was limited at 40.5 MV/m, corresponding to B{sub peak} = 173 mT, in 8{pi}/9 mode. Dual mode measurements on this quench indicate that this quench is not purely magnetic, and so we conclude that this field is not the fundamental limit in SRF cavities.

  10. Superconducting borides

    SciTech Connect (OSTI)

    Fisk, Z.

    1990-01-01T23:59:59.000Z

    A number of superconductors are found among binary and ternary boride compounds. The highest {Tc}'s are often fund near a limiting composition for the compound's stability. Ternary borides have been a fertile area for exploring the interaction between superconductivity and magnetism, and appear to be the area in which further aspects of boride superconductivity will be pursued. 25 refs., 3 tabs.

  11. Apparatus and method for controlling the temperature of the core of a super-conducting transformer

    SciTech Connect (OSTI)

    Golner, Thomas; Pleva, Edward; Mehta, Shirish

    2006-10-10T23:59:59.000Z

    An apparatus for controlling the temperature of a core of a transformer is provided that includes a core, a shield surrounding the core, a cast formed between the core and the shield, and tubing positioned on the shield. The cast directs heat from the core to the shield and cooling fluid is directed through the tubing to cool the shield.

  12. Field limit and nano-scale surface topography of superconducting radio-frequency cavity made of extreme type II superconductor

    E-Print Network [OSTI]

    Kubo, Takayuki

    2014-01-01T23:59:59.000Z

    The field limit of superconducting radio-frequency cavity made of type II superconductor with a large Ginzburg-Landau parameter is studied with taking effects of nano-scale surface topography into account. If the surface is ideally flat, the field limit is imposed by the superheating field. On the surface of cavity, however, nano-defects almost continuously distribute and suppress the superheating field everywhere. The field limit is imposed by an effective superheating field given by the product of the superheating field for ideal flat surface and a suppression factor that contains effects of nano-defects. A nano-defect is modeled by a triangular groove with a depth smaller than the penetration depth. An analytical formula for the suppression factor of bulk and multilayer superconductors are derived in the framework of the London theory. As an immediate application, the suppression factor of the dirty Nb processed by the electropolishing is evaluated by using results of surface topographic study. The estimat...

  13. 2298 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 13, NO. 2, JUNE 2003 Cryogenic Cooling Temperature of HTS Transformers

    E-Print Network [OSTI]

    Chang, Ho-Myung

    , thermal optimization, transformer. I. INTRODUCTION MAIN advantages of HTS power transformers are the small and efficiency. As small size and low power consumption are conflicting in determining the oper- ating at around 77 K [1]. Toward the practical applications, an operation of HTS transformers at temperatures well

  14. SUPERCONDUCTING DEVICES

    E-Print Network [OSTI]

    Clarke, John

    2014-01-01T23:59:59.000Z

    on all aspects of superconducting devices. IEEE Trans.on all aspects vf superconducting devices. The IBM JournalJ. Matisoo, The Superconducting Computer," Scientific

  15. Adaptive-feedback spectral-phase control for interactions with transform-limited ultrashort high-power laser pulses

    E-Print Network [OSTI]

    Umstadter, Donald

    Adaptive-feedback spectral-phase control for interactions with transform-limited ultrashort high-power large spectral bandwidths. The availability of ultrashort pulses (femto- second) of high-power (petawatt Powers, Isaac Ghebregziabher, and Donald Umstadter* Department of Physics and Astronomy, University

  16. New Advance in SuperConducting Materials

    ScienceCinema (OSTI)

    None

    2010-01-08T23:59:59.000Z

    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...  

  17. SUPERCONDUCTING DEVICES

    E-Print Network [OSTI]

    Clarke, John

    2014-01-01T23:59:59.000Z

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

  18. Superconducting materials for large scale applications

    E-Print Network [OSTI]

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

    2004-01-01T23:59:59.000Z

    transmission cables, transformers and fault current limiterscondensers, fault-current limiters and transformers. Study

  19. A statistical rationale for establishing process quality control limits using fixed sample size, for critical current verification of SSC superconducting wire

    SciTech Connect (OSTI)

    Pollock, D.A.; Brown, G.; Capone, D.W. II; Christopherson, D.; Seuntjens, J.M.; Woltz, J.

    1992-03-01T23:59:59.000Z

    The purpose of this paper is to demonstrate a statistical method for verifying superconducting wire process stability as represented by I{sub c}. The paper does not propose changing the I{sub c} testing frequency for wire during Phase 1 of the present Vendor Qualification Program. The actual statistical limits demonstrated for one supplier`s data are not expected to be suitable for all suppliers. However, the method used to develop the limits and the potential for improved process through their use, may be applied equally. Implementing the demonstrated method implies that the current practice of testing all pieces of wire from each billet, for the purpose of detecting manufacturing process errors (i.e. missing a heat-treatment cycle for a part of the billet, etc.) can be replaced by other less costly process control measures. As used in this paper process control limits for critical current are quantitative indicators of the source manufacturing process uniformity. The limits serve as alarms indicating the need for manufacturing process investigation.

  20. NiTi shape-memory transformations: minimum-energy pathways between austenite, martensites, and kinetically-limited intermediate states

    E-Print Network [OSTI]

    Zarkevich, N A

    2014-01-01T23:59:59.000Z

    NiTi is the most used shape-memory alloy, nonetheless, a lack of understanding remains regarding the associated structures and transitions, including their barriers. Using a generalized solid-state nudge elastic band (GSSNEB) method implemented via density-functional theory, we detail the structural transformations in NiTi relevant to shape memory: those between body-centered orthorhombic (BCO) groundstate and a newly identified stable austenite ("glassy" B2-like) structure, including energy barriers (hysteresis) and intermediate structures (observed as a kinetically limited R-phase), and between martensite variants (BCO orientations). All results are in good agreement with available experiment. We contrast the austenite results to those from the often-assumed, but unstable B2. These high- and low-temperature structures and structural transformations provide much needed atomic-scale detail for transitions responsible for NiTi shape-memory effects.

  1. Overview of Superconductivity and Challenges in Applications

    E-Print Network [OSTI]

    Flükiger, Rene

    2012-01-01T23:59:59.000Z

    Considerable progress has been achieved during the last few decades in the various fields of applied superconductivity, while the related low temperature technology has reached a high level. Magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) are so far the most successful applications, with tens of thousands of units worldwide, but high potential can also be recognized in the energy sector, with high energy cables, transformers, motors, generators for wind turbines, fault current limiters and devices for magnetic energy storage. A large number of magnet and cable prototypes have been constructed, showing in all cases high reliability. Large projects involving the construction of magnets, solenoids as well as dipoles and quadrupoles are described in the present book. A very large project, the LHC, is currently in operation, demonstrating that superconductivity is a reliable technology, even in a device of unprecedented high complexity. A project of similar complexity is ITER, a fusion device...

  2. Superconductive wire

    DOE Patents [OSTI]

    Korzekwa, David A. (Los Alamos, NM); Bingert, John F. (Jemez Springs, NM); Peterson, Dean E. (Los Alamos, NM); Sheinberg, Haskell (Santa Fe, NM)

    1995-01-01T23:59:59.000Z

    A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity.

  3. Supertubes versus superconducting tubes

    E-Print Network [OSTI]

    Ruben Cordero; Efrain Rojas

    2005-05-13T23:59:59.000Z

    In this paper we show the relationship between cylindrical D2-branes and cylindrical superconducting membranes described by a generic effective action at the bosonic level. In the first case the extended objects considered, arose as blown up type IIA superstrings to D2-branes, named supertubes. In the second one, the cosmological objects arose from some sort of field theories. The Dirac-Born-Infeld action describing supertubes is shown to be equivalent to the generic effective action describing superconducting membranes via a special transformation.

  4. 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)

    2005-07-22T23:59:59.000Z

    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.

  5. 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)

    2005-03-08T23:59:59.000Z

    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.

  6. Superconducting structure

    DOE Patents [OSTI]

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

    2003-04-01T23:59:59.000Z

    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.

  7. Superconducting Structure

    DOE Patents [OSTI]

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

    2005-09-13T23:59:59.000Z

    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.

  8. New Advances in SuperConducting Materials

    ScienceCinema (OSTI)

    None

    2014-08-12T23:59:59.000Z

    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.

  9. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    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

  10. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Design of the BPA Superconducting 30-MJ Energy Storagefor a Utility Scale Superconducting Magnetic Energy Storagefor a Lnrge Scale Superconducting Magnetic Energy Storage

  11. From Ions to Wires to the Grid: The Transformational Science of LANL Research in High-Tc Superconducting Tapes and Electric Power Applications

    SciTech Connect (OSTI)

    Ken Marken

    2009-05-20T23:59:59.000Z

    The Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability (OE) has been tasked to lead national efforts to modernize the electric grid, enhance security and reliability of the energy infrastructure, and facilitate recovery from disruptions to energy supplies. LANL has pioneered the development of coated conductors – high-temperature superconducting (HTS) tapes – which permit dramatically greater current densities than conventional copper cable, and enable new technologies to secure the national electric grid. Sustained world-class research from concept, demonstration, transfer, and ongoing industrial support has moved this idea from the laboratory to the commercial marketplace.

  12. From Ions to Wires to the Grid: The Transformational Science of LANL Research in High-Tc Superconducting Tapes and Electric Power Applications

    SciTech Connect (OSTI)

    Marken, Ken (Superconductivity Technology Center, Los Alamos) [Superconductivity Technology Center, Los Alamos

    2009-05-20T23:59:59.000Z

    The Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability (OE) has been tasked to lead national efforts to modernize the electric grid, enhance security and reliability of the energy infrastructure, and facilitate recovery from disruptions to energy supplies. LANL has pioneered the development of coated conductors - high-temperature superconducting (HTS) tapes - which permit dramatically greater current densities than conventional copper cable, and enable new technologies to secure the national electric grid. Sustained world-class research from concept, demonstration, transfer, and ongoing industrial support has moved this idea from the laboratory to the commercial marketplace.

  13. From Ions to Wires to the Grid: The Transformational Science of LANL Research in High-Tc Superconducting Tapes and Electric Power Applications

    ScienceCinema (OSTI)

    Ken Marken

    2010-01-08T23:59:59.000Z

    The Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability (OE) has been tasked to lead national efforts to modernize the electric grid, enhance security and reliability of the energy infrastructure, and facilitate recovery from disruptions to energy supplies. LANL has pioneered the development of coated conductors ? high-temperature superconducting (HTS) tapes ? which permit dramatically greater current densities than conventional copper cable, and enable new technologies to secure the national electric grid. Sustained world-class research from concept, demonstration, transfer, and ongoing industrial support has moved this idea from the laboratory to the commercial marketplace.

  14. Kink in superconducting cosmic string: exact solution

    E-Print Network [OSTI]

    Ernst Trojan

    2014-12-24T23:59:59.000Z

    We solve the equations of motion and find the Lorentz transformation associated with a kink in superconducting cosmic string. The kink velocity does not depend on its amplitude. The kink amplitude cannot be arbitrary but it varies within definite range and determines the explicit form of the relevant Lorentz transformation.

  15. Superconducting Magnet Division

    E-Print Network [OSTI]

    Superconducting Magnet Division DOE NP Program Review - July 06 1 Brookhaven Magnet Division - Nuclear Physics Program Support Activities Superconducting Magnet Program RHIC Operations Support Spin Summary Peter Wanderer, DOE review, July 25, 2006 Acting Head, Superconducting Magnet Division #12

  16. Superconducting Spintronics

    E-Print Network [OSTI]

    Linder, Jacob; Robinson, Jason W. A.

    2015-01-01T23:59:59.000Z

    such as the uranium based heavy- fermion compounds [35, 36] . This includes the creation of spin cur- rents without resistance [37–41] and spin-valve devices controlling the resistance of the junction via the superconducting critical temper- ature Tc [42]. There are... for each spin species [109]. Outlook and perspectives We end the review by offering our perspective on possible direc- tions that may be fruitful to explore in order to develop supercon- ducting spintronics. While progress has been most pronounced...

  17. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

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

  18. Superconducting Topological Insulators

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

    Superconducting Topological Insulators Superconducting Topological Insulators Print Wednesday, 26 January 2011 00:00 Three-dimensional topological insulators (TIs), discovered...

  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. 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

  1. Superconductivity for Electric Systems

    E-Print Network [OSTI]

    Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period January 1, 2007 to March 31, 2007 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For: 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.

    2010-01-01T23:59:59.000Z

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

  4. Spinning superconducting electrovacuum soliton

    E-Print Network [OSTI]

    Irina Dymnikova

    2006-07-24T23:59:59.000Z

    In nonlinear electrodynamics coupled to general relativity and satisfying the weak energy condition, a spherically symmetric electrically charged electrovacuum soliton has obligatory de Sitter center in which the electric field vanishes while the energy density of electromagnetic vacuum achieves its maximal value. De Sitter vacuum supplies a particle with the finite positive electromagnetic mass related to breaking of space-time symmetry from the de Sitter group in the origin. By the G\\"urses-G\\"ursey algorithm based on the Newman-Trautman technique it is transformed into a spinning electrovacuum soliton asymptotically Kerr-Newman for a distant observer. De Sitter center becomes de Sitter equatorial disk which has both perfect conductor and ideal diamagnetic properties. The interior de Sitter vacuum disk displays superconducting behavior within a single spinning soliton. This behavior found for an arbitrary nonlinear lagrangian ${\\cal L}(F)$, is generic for the class of regular spinning electrovacuum solutions describing both black holes and particle-like structures.

  5. 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.

    2006-05-11T23:59:59.000Z

    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.

  6. Quadratic superconducting cosmic strings revisited

    E-Print Network [OSTI]

    Mustapha Azreg-Aïnou

    2008-02-22T23:59:59.000Z

    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.

  7. 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 ...

  8. ENERGY DIVISION STATUS OF SUPERCONDUCTING POWER TRANSFORMER

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem Not Found Item Not Found The itemAIR57451 CleanFOR IMMEDIATEDurable ZincEDIVISION

  9. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01T23:59:59.000Z

    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.

  10. Superconducting RF Cryomodule Demagnetization

    E-Print Network [OSTI]

    Crawford, Anthony C

    2015-01-01T23:59:59.000Z

    This note presents measurements that support the proposition that it is feasible to demagnetize a fully assembled superconducting RF cryomodule.

  11. Basic principle of superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-11-10T23:59:59.000Z

    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.

  12. Superconducting Magnet Division

    E-Print Network [OSTI]

    McDonald, Kirk

    Superconducting Magnet Division Ramesh Gupta 20T Target Solenoid with HTS Insert Solenoid Capture Laboratory New York, USA http://www.bnl.gov/magnets/staff/gupta #12;Superconducting Magnet Division Ramesh of HTS may significantly reduce the amount of Tungsten shielding · Summary #12;Superconducting Magnet

  13. Superconductivity, Superfluidity and Holography

    E-Print Network [OSTI]

    Alberto Salvio

    2013-01-16T23:59:59.000Z

    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. Protective link for superconducting coil

    DOE Patents [OSTI]

    Umans, Stephen D. (Belmont, MA)

    2009-12-08T23:59:59.000Z

    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.

  15. Superconducting microfabricated ion traps

    E-Print Network [OSTI]

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

    2010-12-14T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

    Norem, James H.; Pellin, Michael J.

    2013-06-11T23:59:59.000Z

    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. 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

  18. Superconductive radiofrequency window assembly

    DOE Patents [OSTI]

    Phillips, H.L.; Elliott, T.S.

    1998-05-19T23:59:59.000Z

    The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The SRF window assembly has a superconducting metal-ceramic design. The SRF window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. 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. 11 figs.

  19. Superconducting radiofrequency window assembly

    DOE Patents [OSTI]

    Phillips, H.L.; Elliott, T.S.

    1997-03-11T23:59:59.000Z

    The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly has a superconducting metal-ceramic design. The srf window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. 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. 11 figs.

  20. Superconducting shielded core reactor with reduced AC losses

    DOE Patents [OSTI]

    Cha, Yung S.; Hull, John R.

    2006-04-04T23:59:59.000Z

    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.

  1. 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)

    1991-01-01T23:59:59.000Z

    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.

  2. 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...

  3. Entropic inequalities for noncomposite quantum systems realized by superconducting circuits

    E-Print Network [OSTI]

    A. K. Fedorov; E. O. Kiktenko; O. V. Man'ko; V. I. Man'ko

    2014-12-31T23:59:59.000Z

    We study a class of entropic inequalities obtained for noncomposite quantum system realized by a many-level superconducting circuit. By using a mapping on bipartite quantum states, we consider possible realization schemes of various quantum logic gates for noncomposite quantum systems. In this framework, we discuss $\\log{N}$ entropic inequalities for Shannon and R\\'eniy entropies based on the quantum Fourier transform. Implementation of the quantum Fourier transform on a quantum processor based on many-level superconducting circuits opens a way for experimental verification of $\\log{N}$ entropic inequalities.

  4. 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

  5. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Yonit Hochberg; Yue Zhao; Kathryn M. Zurek

    2015-04-27T23:59:59.000Z

    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.

  6. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Hochberg, Yonit; Zurek, Kathryn M

    2015-01-01T23:59:59.000Z

    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.

  7. Superconducting Radiofrequency (SRF) Accelerator Cavities

    ScienceCinema (OSTI)

    Reece, Charlie

    2014-05-22T23:59:59.000Z

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

  8. Superconducting Magnet Technology for Future Hadron Colliders

    E-Print Network [OSTI]

    Scanlan, R.M.

    2011-01-01T23:59:59.000Z

    I. Superconducting Magnet Technology for Future Hadl"On1994. M.N. Wilson, Superconducting Magnets (Clarendon Press,The application of superconducting magnets to large-scale

  9. Superconducting vortex pinning with artificially prepared nanostructures

    E-Print Network [OSTI]

    Rosen, Yaniv Jacob

    K. Schuller, “Enhanced superconducting vortex pinning withat T/Tc = 0.99 of a superconducting Nb thin film on aof the triangles. The superconducting critical temperature

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

    E-Print Network [OSTI]

    Fominov, Yakov

    Fluctuations in systemsFluctuations in systems with superconducting islandswith superconductingTwo mechanism of TTcc suppressionsuppression #12;SuperconductingSuperconductingmetal transitionsmetal: Superconductive transitionGrains: Superconductive transition #12;Islands on a film: what's the difference

  11. Superconducting active impedance converter

    DOE Patents [OSTI]

    Ginley, D.S.; Hietala, V.M.; Martens, J.S.

    1993-11-16T23:59:59.000Z

    A transimpedance amplifier for use with high temperature superconducting, other superconducting, and conventional semiconductors 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. 12 figures.

  12. Introduction to Color Superconductivity

    E-Print Network [OSTI]

    G. Nardulli

    2006-10-23T23:59:59.000Z

    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.

  13. Superconducting active impedance converter

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

    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.

  14. Superconducting thermoelectric generator

    DOE Patents [OSTI]

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

    1998-05-05T23:59:59.000Z

    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.

  15. Superconducting thermoelectric generator

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

  16. Superconducting thermoelectric generator

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

    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.

  17. Superconducting transmission line particle detector

    DOE Patents [OSTI]

    Gray, Kenneth E. (Naperville, IL)

    1989-01-01T23:59:59.000Z

    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.

  18. Superconducting transmission line particle detector

    DOE Patents [OSTI]

    Gray, K.E.

    1988-07-28T23:59:59.000Z

    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.

  19. High temperature interfacial superconductivity

    DOE Patents [OSTI]

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

    2012-06-19T23:59:59.000Z

    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.

  20. Superconducting radiofrequency window assembly

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

    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.

  1. Superconductive radiofrequency window assembly

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

  2. Simulation and Analysis of Superconducting Traveling-Wave Parametric Amplifiers

    E-Print Network [OSTI]

    Saptarshi Chaudhuri; Jiansong Gao; Kent Irwin

    2015-01-11T23:59:59.000Z

    Superconducting parametric amplifiers have great promise for quantum-limited readout of superconducting qubits and detectors. Until recently, most superconducting parametric amplifiers had been based on resonant structures, limiting their bandwidth and dynamic range. Broadband traveling-wave parametric amplifiers based both on the nonlinear kinetic inductance of superconducting thin films and on Josephson junctions are in development. By modifying the dispersion property of the amplifier circuit, referred to as dispersion engineering, the gain can be greatly enhanced and the size can be reduced. We present two theoretical frameworks for analyzing and understanding such parametric amplifiers: (1) generalized coupled-mode equations and (2) a finite difference time domain (FDTD) model combined with a small signal analysis. We show how these analytical and numerical tools may be used to understand device performance.

  3. The ion pairs and superconducting bosons

    E-Print Network [OSTI]

    V. N. Minasyan

    2009-02-11T23:59:59.000Z

    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.

  4. Witten Index and Superconducting Strings

    E-Print Network [OSTI]

    V. K. Oikonomou

    2010-01-14T23:59:59.000Z

    The Yukawa interaction sector of superstring inspired models that give superconducting strings, can be described in terms of a supersymmetric quantum mechanics algebra. We relate the Witten index of susy quantum mechanics with an index characteristic to superconducting string models.

  5. 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

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

    E-Print Network [OSTI]

    Zocco, Diego Andrés

    2011-01-01T23:59:59.000Z

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

  7. Orbit Spaces in Superconductivity

    E-Print Network [OSTI]

    Vittorino Talamini

    2006-07-30T23:59:59.000Z

    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.

  8. Crossovers between superconducting symmetry classes

    E-Print Network [OSTI]

    V. A. Koziy; M. A. Skvortsov

    2011-06-20T23:59:59.000Z

    We study the average density of states in a small metallic grain coupled to two superconductors with the phase difference $\\pi$, in a magnetic field. The spectrum of the low-energy excitations in the grain is described by the random matrix theory whose symmetry depends on the magnetic field strength and coupling to the superconductors. In the limiting cases, a pure superconducting symmetry class is realized. For intermediate magnetic fields or couplings to the superconductors, the system experiences a crossover between different symmetry classes. With the help of the supersymmetric sigma-model we derive the exact expressions for the average density of states in the crossovers between the symmetry classes A-C and CI-C.

  9. Superconducting Magnets for Particle Accelerators

    E-Print Network [OSTI]

    Rossi, L

    2012-01-01T23:59:59.000Z

    Superconductivity has been the most influential technology in the field of accelerators in the last 30 years. Since the commissioning of the Tevatron, which demonstrated the use and operability of superconductivity on a large scale, superconducting magnets and rf cavities have been at the heart of all new large accelerators. Superconducting magnets have been the invariable choice for large colliders, as well as cyclotrons and large synchrotrons. In spite of the long history of success, superconductivity remains a difficult technology, requires adequate R&D and suitable preparation, and has a relatively high cost. Hence, it is not surprising that the development has also been marked by a few setbacks. This article is a review of the main superconducting accelerator magnet projects; it highlights the main characteristics and main achievements, and gives a perspective on the development of superconducting magnets for the future generation of very high energy colliders.

  10. SUPERCONDUCTIVITY PROGRAM RESEARCH AND DEVELOPMENT High Temperature Superconductivity (HTS) is a technology with the potential

    E-Print Network [OSTI]

    #12;SUPERCONDUCTIVITY PROGRAM RESEARCH AND DEVELOPMENT High Temperature Superconductivity (HTS-of-way. The Department of Energy's efforts to advance High Temperature Superconductivity combine major national strengths: the Superconductivity Partnership Initiative (SPI), the 2nd Generation Wire Initiative

  11. 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

  12. Superconducting thermoelectric generator

    DOE Patents [OSTI]

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

    1994-01-01T23:59:59.000Z

    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.

  13. Competition between Superconductivity

    E-Print Network [OSTI]

    Fominov, Yakov

    . Liu, D.V. Haviland, B. Nease, and A.M. Goldman, PRB 47, 5931 (1993)S I Bi films Rc = 6.45 k } M ? 0.M. Goldman, PRB 47, 5931 (1993) } M ? metal Drude conductivity + quantum corrections G ln T SMIT #12;Suppression of Superconductivity by Disorder MoxSi1-x films S. Okuma, T. Terashima, and Kokubo, PRB 58, 2816

  14. Langmuir vacuum and superconductivity

    SciTech Connect (OSTI)

    Veklenko, B. A. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2012-06-15T23:59:59.000Z

    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.

  15. seshadri@mrl Superconductivity

    E-Print Network [OSTI]

    Akhmedov, Azer

    Superconducting magnets and MRI The rudiments of Bardeen-Cooper-Schrieffer theory High TC Newer systems #12 are they achieved: Cascaded refrigeration processes involving the successive compression and expansion of different?ng 273.15 32 0 Water boiling 373.15 212 100 Refrigeration in a nutshell: Compress a fluid isothermally

  16. 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

  17. Vortex avalanches with robust statistics observed in superconducting niobium E. Altshuler,1,2

    E-Print Network [OSTI]

    Zeldov, Eli

    Vortex avalanches with robust statistics observed in superconducting niobium E. Altshuler,1,2 T. H topography of superconducting niobium samples as the external field is slowly increased. The avalanche size in Ref. 11, was quite limited, being based on only a few hundred events. Nowak et al.12 studied niobium

  18. 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

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

    SciTech Connect (OSTI)

    Rogers, J.D. (comp.)

    1982-02-01T23:59:59.000Z

    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.

  20. Market Transformation

    SciTech Connect (OSTI)

    Not Available

    2008-09-01T23:59:59.000Z

    Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its market transformation subprogram.

  1. Transformation Composition

    E-Print Network [OSTI]

    Drewes, Frank

    Proc. AGTIVE'99, to appear in LNCS Graph Transformation Modules and their Composition ? Frank,knirsch,kreo,kuskeg@informatik.uni-bremen.de Abstract. In this paper, we investigate the notion of transformation modules as a structuring principle. Based on the notion of transformation units, a concept that allows to specify binary relations on graphs

  2. transformations: representations

    E-Print Network [OSTI]

    Nguyen, Dat H.

    Overview 1. Number transformations: from one base to another 2. Integer representations 3. Real rate, caches... #12; ECS 50, Discussion on 4/25 2 Integer Transformation: From Decimal to Binary Let, Discussion on 4/25 3 Integer Transformation: From Binary to Decimal Compute the weight of each digit position

  3. 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

  4. 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

  5. Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara

    E-Print Network [OSTI]

    Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara Department of Physics, University to the distinction between normal metals and insulators: the superconducting ``metal'' with delocalized qua- siparticle excitations and the superconducting ``insulator'' with localized quasiparticles. We describe

  6. Superconducting solenoids for the Muon collider

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    muon collider has superconducting solenoids as an integralLBNL-44303 SCMAG-690 Superconducting Solenoids for the MuonDE-AC03-76SFOOO98. J Superconducting Solenoids for the Muon

  7. SUPERCONDUCTING SHIELDING By W. O. HAMILTON,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    41. SUPERCONDUCTING SHIELDING By W. O. HAMILTON, Stanford University, Department of Physics, Stanford, California (U.S.A.). Abstract. 2014 Superconducting shields offer the possibility of obtaining shielding from external time varying fields. Various techniques of superconducting shielding

  8. HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01T23:59:59.000Z

    D. C. 'Niobium-Titanium Superconducting Material s ', in S.14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.SUMAG-68 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS* C.

  9. 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)

    2015-07-01T23:59:59.000Z

    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.

  10. Superconductivity in graphite intercalation compounds

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

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

    2015-07-01T23:59:59.000Z

    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 aremore »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

  11. Superconductivity from D3/D7: Holographic Pion Superfluid

    E-Print Network [OSTI]

    Pallab Basu; Jianyang He; Anindya Mukherjee; Hsien-Hang Shieh

    2008-10-22T23:59:59.000Z

    We show that a D3/D7 system (at zero quark mass limit) at finite isospin chemical potential goes through a superconductor (superfluid) like phase transition. This is similar to a flavored superfluid phase studied in QCD literature, where mesonic operators condensate. We have studied the frequency dependent conductivity of the condensate and found a delta function pole in the zero frequency limit. This is an example of superconductivity in a string theory context. Consequently we have found a superfluid/supercurrent type solution and studied the associated phase diagram. The superconducting transition changes from second order to first order at a critical superfluid velocity. We have studied various properties of the superconducting system like superfluid density, energy gap, second sound etc. We investigate the possibility of the isospin chemical potential modifying the embedding of the flavor branes by checking whether the transverse scalars also condense at low temperature. This however does not seem to be the case.

  12. Landscape of superconducting membranes

    E-Print Network [OSTI]

    Frederik Denef; Sean A. Hartnoll

    2009-03-20T23:59:59.000Z

    The AdS/CFT correspondence may connect the landscape of string vacua and the `atomic landscape' of condensed matter physics. We study the stability of a landscape of IR fixed points of N=2 large N gauge theories in 2+1 dimensions, dual to Sasaki-Einstein compactifications of M theory, towards a superconducting state. By exhibiting instabilities of charged black holes in these compactifications, we show that many of these theories have charged operators that condense when the theory is placed at a finite chemical potential. We compute a statistical distribution of critical superconducting temperatures for a subset of these theories. With a chemical potential of one milliVolt, we find critical temperatures ranging between 0.24 and 165 degrees Kelvin.

  13. Competition between singlet and triplet superconductivity

    E-Print Network [OSTI]

    Tian De Cao; Tie Bang Wang

    2009-10-04T23:59:59.000Z

    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.

  14. Equilibrium Distributions and Superconductivity

    E-Print Network [OSTI]

    Ashot Vagharshakyan

    2011-06-07T23:59:59.000Z

    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.

  15. Superconducting magnet wire

    DOE Patents [OSTI]

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

    1986-01-01T23:59:59.000Z

    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..

  16. Helical superconducting black holes

    E-Print Network [OSTI]

    Aristomenis Donos; Jerome P. Gauntlett

    2012-05-17T23:59:59.000Z

    We construct novel static, asymptotically $AdS_5$ black hole solutions with Bianchi VII$_0$ symmetry that are holographically dual to superconducting phases in four spacetime dimensions with a helical p-wave order. We calculate the precise temperature dependence of the pitch of the helical order. At zero temperature the black holes have vanishing entropy and approach domain wall solutions that reveal homogenous, non-isotropic dual ground states with emergent scaling symmetry.

  17. Superconducting VAR control. [Patent application

    DOE Patents [OSTI]

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

    1980-12-05T23:59:59.000Z

    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.

  18. Superconducting electric power applications

    SciTech Connect (OSTI)

    Blaugher, R.D. [National Renewable Energy Lab., Golden, CO (United States)

    1997-06-01T23:59:59.000Z

    The application of superconductors to electric power systems has been actively pursued over the past 30 years. Following the realization of high-field, high-current superconductors in 1961, researchers applied these type II materials, such as Nb-Ti and Nb{sub 3}Sn, to laboratory magnets, followed by generators, motors, and transmission cables. Successful prototypes for the latter were constructed and tested by the mid-1980s. It is fair to assume that widespread utility acceptance of these low-temperature superconducting (LTS) power applications was compromised by the necessity for liquid helium cooling. The discovery of the high-temperature superconductors (HTS) in 1986, which offered the prospect for liquid nitrogen cooling, provided renewed interest and impetus and spurred the development of HTS power components. The expectations for HTS power components are, in fact, near realization, as a result of the rapid worldwide progress in HTS wire and tape development. This paper will review the history and present status of superconducting power-system-related applications. The major problems facing this technology and the prospects for commercialization and eventual integration into the utility sector will be discussed. General acceptance for superconducting power equipment by the electric utilities and other end-users will ultimately be based on the respective system performance, efficiency, reliability and maintenance, operational lifetime, and installed cost compared to conventional technologies.

  19. Superconducting dark energy

    E-Print Network [OSTI]

    Shi-Dong Liang; Tiberiu Harko

    2015-04-10T23:59:59.000Z

    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.

  20. Superconductivity and Superfluidity

    E-Print Network [OSTI]

    B. V. Vasiliev

    2013-10-31T23:59:59.000Z

    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.

  1. Flavor Superconductivity & Superfluidity

    E-Print Network [OSTI]

    Matthias Kaminski

    2010-02-25T23:59:59.000Z

    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.

  2. THE TECHNOLOGY OF SUPERCONDUCTING ACCELERATOR DIPOLES

    E-Print Network [OSTI]

    Hassenzahl, W.V.

    2010-01-01T23:59:59.000Z

    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

  3. 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)

    2005-01-18T23:59:59.000Z

    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.

  4. Market Transformation

    Fuel Cell Technologies Publication and Product Library (EERE)

    This Fuel Cell Technologies Program fact sheet outlines current status and challenges in the market transformation of hydrogen and fuel cell technologies.

  5. Surface Superconductivity in Niobium for Superconducting RF Cavities0

    E-Print Network [OSTI]

    Surface Superconductivity in Niobium for Superconducting RF Cavities0 S. Casalbuoni1,2 , E) parameters of the ultrapure niobium used for the fabrication of the nine-cell 1.3 GHz cavities for the lin.3 GHz nine-cell cavities which are made from pure niobium and cooled by superfluid helium at 2 K. The 0

  6. Optimization of superconducting tiling pattern for superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.

    1996-09-17T23:59:59.000Z

    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.

  7. Optimization of superconducting tiling pattern for superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1996-01-01T23:59:59.000Z

    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.

  8. Losses in superconducting Niobium Films caused by Interface Tunnel Exchange

    E-Print Network [OSTI]

    Junginger, Tobias; Welsch, Carsten

    2012-01-01T23:59:59.000Z

    Identifying the loss mechanisms of niobium film cavities enables an accurate determination of applications for future accelerator projects and points to research topics required to mitigate their limitations. Measurements on samples show that the electric field is a dominant loss mechanism for niobium films, acting through interface tunneling between localized states in surface oxides and delocalized states in the superconducting niobium.

  9. Power superconducting power transmission cable

    DOE Patents [OSTI]

    Ashworth, Stephen P. (Cambridge, GB)

    2003-01-01T23:59:59.000Z

    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.

  10. 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)

    2003-09-23T23:59:59.000Z

    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.

  11. 2003 Annual Superconductivity2003 Annual Superconductivity Peer ReviewPeer Review

    E-Print Network [OSTI]

    2003 Annual Superconductivity2003 Annual Superconductivity Peer ReviewPeer Review Raghu;Superconductivity Program at NREL for Electric SystemsSuperconductivity Program at NREL for Electric Systems Non) Industry CRADA:Industry CRADA: Oxford Superconducting Technologies (Ken Marken, Miao Hanping) *University

  12. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructure of All-Polymer.Supercomputing on aSuperconducting Topological

  13. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructure of All-Polymer.Supercomputing on aSuperconducting

  14. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructure of All-Polymer.Supercomputing onSuperconducting Topological

  15. Superconductivity Centennial | Jefferson Lab

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructure of All-Polymer.Supercomputing onSuperconducting

  16. Weak Measurement and Feedback in Superconducting Quantum Circuits

    E-Print Network [OSTI]

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

    2015-07-16T23:59:59.000Z

    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.

  17. Overview on superconducting photoinjectors

    E-Print Network [OSTI]

    Arnold, A

    2011-01-01T23:59:59.000Z

    The success of most of the proposed energy recovery linac (ERL) based electron accelerator projects for future storage ring replacements (SRR) and high power IR–free-electron lasers (FELs) largely depends on the development of an appropriate source. For example, to meet the FEL specifications [J.W. Lewellen, Proc. SPIE Int. Soc. Opt. Eng. 5534, 22 (2004)] electron beams with an unprecedented combination of high brightness, low emittance (0.1 µmrad), and high average current (hundreds of mA) are required. An elegant way to create a beam of such quality is to combine the high beam quality of a normal conducting rf photoinjector with the superconducting technology, i.e., to build a superconducting rf photoinjector (SRF gun). SRF gun R&D programs based on different approaches have been launched at a growing number of institutes and companies (AES, Beijing University, BESSY, BNL, DESY, FZD, TJNAF, Niowave, NPS, Wisconsin University). Substantial progress was achieved in recent years and the first long term ...

  18. Overview of Superconducting Photoinjectors

    E-Print Network [OSTI]

    Arnold, A

    2009-01-01T23:59:59.000Z

    The success of most of the proposed ERL based electron accelerator projects for future storage ring replacements (SRR) and high power IR-FELs is contingent upon the development of an appropriate source. Electron beams with an unprecedented combination of high brightness, low emittance (0.1 µm rad) and high average current (hundreds of mA) are required to meet the FEL specification [1]. An elegant way to create such an unique beam is to combine the high beam quality of a normal conducting RF photo injector with the superconducting technology to get a superconducting RF photo injector (SRF gun). SRF gun R&D programs based on different approaches are under investigation at a growing number of institutes and companies (AES, Beijing University, BESSY, BNL, DESY, FZD, JLab, Niowave, NPS, Wisconsin University). Lot of progress could be achieved during the last years and first long term operation was demonstrated at the FZD [2]. In the near future, this effort will lead to SRF guns, which are indispensab...

  19. Superconductivity for electric systems program plan, FY 1996--FY 2000

    SciTech Connect (OSTI)

    NONE

    1996-03-01T23:59:59.000Z

    This describes a comprehensive, integrated approach for the development of HTS (high-temperature superconductivity) technology for cost-effective use in electric power applications. This approach supports the program`s mission: to develop the technology that could lead to industrial commercialization of HTS electric power applications, such as fault-current limiters, motors, generators, transmission cables, superinductors, and superconducting energy storage. The vision is that, by 2010, the US power systems equipment industry will regain a major share of the global market by offering superconducting products that outperform the competition; and in US, the power grid will gain increased efficiency and stability by incorporating many kinds of HTS devices. After an overview and a discussion of the program plan (wires, systems technology, partnership initiative), this document discusses technology status, stakeholders, and the role of US DOE.

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

    E-Print Network [OSTI]

    Dvir Kafri; Prabin Adhikari; Jacob M. Taylor

    2015-04-15T23:59:59.000Z

    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.

  1. Reaching 10 ms single photon lifetimes for superconducting aluminum cavities

    E-Print Network [OSTI]

    M. Reagor; Hanhee Paik; G. Catelani; L. Sun; C. Axline; E. Holland; I. M. Pop; N. A. Masluk; T. Brecht; L. Frunzio; M. H. Devoret; L. I. Glazman; R. J. Schoelkopf

    2013-05-22T23:59:59.000Z

    Three-dimensional microwave cavities have recently been combined with superconducting qubits in the circuit quantum electrodynamics (cQED) architecture. These cavities should have less sensitivity to dielectric and conductor losses at surfaces and interfaces, which currently limit the performance of planar resonators. We expect that significantly (>10^3) higher quality factors and longer lifetimes should be achievable for 3D structures. Motivated by this principle, we have reached internal quality factors greater than 0.5x10^9 and intrinsic lifetimes of 0.01 seconds for multiple aluminum superconducting cavity resonators at single photon energies and millikelvin temperatures. These improvements could enable long lived quantum memories with submicrosecond access times when strongly coupled to superconducting qubits.

  2. Preliminary Test Results for the MICE Spectrometer Superconducting Solenoids

    E-Print Network [OSTI]

    Virostek, Steve P.

    2009-01-01T23:59:59.000Z

    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,

  3. Quantum State Protection and Transfer Using Superconducting Qubits

    E-Print Network [OSTI]

    Keane, Kyle Michael

    2012-01-01T23:59:59.000Z

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

  4. SUPERCONDUCTING TRANSITION EDGE BOLOMETER AND NOISE IN THIN FILMS

    E-Print Network [OSTI]

    Yeh, Nan-Hsiung

    2011-01-01T23:59:59.000Z

    a) Composite Al superconducting bolometer (b) Composite SNSLBL-8019 SUPERCONDUCTING TRANSITION EDGE BOLOMETER AND INrights . LBL-8019 SUPERCONDUCTING TRANSITION EDGE BOLOMETER

  5. Special issue on quantum computing with superconducting qubits

    E-Print Network [OSTI]

    Korotkov, Alexander N.

    2009-01-01T23:59:59.000Z

    on quantum computing with superconducting qubits 10. Shaw,quantum computing with superconducting qubits Alexander N.years ago the ?rst superconducting qubit was demonstrated

  6. FORCED TWO PHASE HELIUM COOLING OF LARGE SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    DIAMETER TPC THIN SUPERCONDUCTING SOLENOID . 'i.A. Green,and Construction of a Superconducting Stabilized AluminumM.A. Green, "Large Superconducting Detector Magnets with

  7. Exotic superconducting phases of ultracold atom mixtures on triangular lattices

    E-Print Network [OSTI]

    Mathey, Ludwig; Tsai, Shan-Wen; Castro Neto, Antonio H.

    2007-01-01T23:59:59.000Z

    Exotic Superconducting Phases of Ultracold Atom Mixtures onlattice contain exotic superconducting phases. For spin-1/2competition between superconducting phases with di?erent

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

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Thefailure of the first superconducting coil at the Lawrence

  9. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01T23:59:59.000Z

    274 Progress on the Superconducting Magnets for the MICEM. A Green and J. M. Rey, “Superconducting Solenoids for anG, “Supercritically Cooled Superconducting Muon Channel,”

  10. A superconducting-nanowire 3-terminal electronic device

    E-Print Network [OSTI]

    Adam N. McCaughan; Karl K. Berggren

    2014-03-25T23:59:59.000Z

    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.

  11. Radio Broadcasts from Superconducting Strings

    E-Print Network [OSTI]

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

    2012-05-14T23:59:59.000Z

    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.

  12. Mesoscopic superconductivity in ultrasmall metallic grains

    SciTech Connect (OSTI)

    Alhassid, Y. [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520 (United States); Nesterov, K. N. [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520 (United States); CEA, INAC-SPSMS, F-38000 Grenoble (France)

    2014-10-15T23:59:59.000Z

    A nano-scale metallic grain (nanoparticle) with irregular boundaries in which the single-particle dynamics are chaotic is a zero-dimensional system described by the so-called universal Hamiltonian in the limit of a large number of electrons. The interaction part of this Hamiltonian includes a superconducting pairing term and a ferromagnetic exchange term. Spin-orbit scattering breaks spin symmetry and suppresses the exchange interaction term. Of particular interest is the fluctuation-dominated regime, typical of the smallest grains in the experiments, in which the bulk pairing gap is comparable to or smaller than the single-particle mean-level spacing, and the Bardeen-Cooper-Schrieffer (BCS) mean-field theory of superconductivity is no longer valid. Here we study the crossover between the BCS and fluctuation-dominated regimes in two limits. In the absence of spin-orbit scattering, the pairing and exchange interaction terms compete with each other. We describe the signatures of this competition in thermodynamic observables, the heat capacity and spin susceptibility. In the presence of strong spin-orbit scattering, the exchange interaction term can be ignored. We discuss how the magnetic-field response of discrete energy levels in such a nanoparticle is affected by pairing correlations. We identify signatures of pairing correlations in this response, which are detectable even in the fluctuation-dominated regime.

  13. SPATIAL TRANSFORMATIONS 1 Running head: Spatial transformations

    E-Print Network [OSTI]

    Zacks, Jeffrey M.

    SPATIAL TRANSFORMATIONS 1 Running head: Spatial transformations Multiple Systems for Spatial Imagery: Transformations of Objects and Bodies Jeffrey M. Zacks* and Barbara Tversky * Washington COGNITION & COMPUTATION #12;SPATIAL TRANSFORMATIONS 2 Abstract Problem-solving often requires imagining

  14. Superconducting dark energy

    E-Print Network [OSTI]

    Liang, Shi-Dong

    2015-01-01T23:59:59.000Z

    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 fact...

  15. Superconducting magnetic energy storage

    SciTech Connect (OSTI)

    Hassenzahl, W.

    1988-08-01T23:59:59.000Z

    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.

  16. Superconducting magnetic coil

    DOE Patents [OSTI]

    Aized, D.; Schwall, R.E.

    1999-06-22T23:59:59.000Z

    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.

  17. Superconducting energy storage

    SciTech Connect (OSTI)

    Giese, R.F.

    1993-10-01T23:59:59.000Z

    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.

  18. Superconducting magnetic coil

    DOE Patents [OSTI]

    Aized, Dawood (Marlboro, MA); Schwall, Robert E. (Northborough, MA)

    1999-06-22T23:59:59.000Z

    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.

  19. Fourier Transform Pairs The Fourier transform transforms a function of

    E-Print Network [OSTI]

    Masci, Frank

    Fourier Transform Pairs The Fourier transform transforms a function of time, f(t), into a function of frequency, F(s): F {f(t)}(s) = F(s) = Z - f(t)e- j2st dt. The inverse Fourier transform transforms a func. The inverse Fourier transform of the Fourier trans- form is the identity transform: f(t) = Z - Z - f()e- j2s

  20. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

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

    1998-03-03T23:59:59.000Z

    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.

  1. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL); Mulcahy, Thomas M. (Western Springs, IL)

    1998-01-01T23:59:59.000Z

    A mixed-mu superconducting bearing 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.

  2. 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.

  3. 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...

  4. Process for producing clad superconductive materials

    DOE Patents [OSTI]

    Cass, Richard B. (Ringoes, NJ); Ott, Kevin C. (Los Alamos, NM); Peterson, Dean E. (Los Alamos, NM)

    1992-01-01T23:59:59.000Z

    A process for fabricating superconducting composite wire by the steps of placing a superconductive precursor admixture capable of undergoing a self propagating combustion in stoichiometric amounts sufficient to form a superconductive product within a metal tube, sealing one end of said tube, igniting said superconductive precursor admixture whereby said superconductive precursor admixture endburns along the length of the admixture, and cross-section reducing said tube at a rate substantially equal to the rate of burning of said superconductive precursor admixture and at a point substantially planar with the burnfront of the superconductive precursor mixture, whereby a clad superconductive product is formed in situ, the product characterized as superconductive without a subsequent sintering stage, is disclosed.

  5. The challenge of unconventional superconductivity.

    SciTech Connect (OSTI)

    Norman, M. R. (Materials Science Division)

    2011-04-08T23:59:59.000Z

    During the past few decades, several new classes of superconductors have been discovered that do not appear to be related to traditional superconductors. The source of the superconductivity of these materials is likely different from the electron-ion interactions that are at the heart of conventional superconductivity. Developing a rigorous theory for any of these classes of materials has proven to be a difficult challenge and will remain one of the major problems in physics in the decades to come.

  6. Localized Fermions on Superconducting Domain Walls and Extended Supersymmetry with non-trivial Topological Charges

    E-Print Network [OSTI]

    V. K. Oikonomou

    2014-06-05T23:59:59.000Z

    In this letter we demonstrate that the fermionic zero modes on a superconducting domain wall can be associated to an one dimensional $N=6$ supersymmetry that contains non-trivial topological charges. In addition, the system also possesses three distinct $N=4$ supersymmetries with non-trivial topological charges and we also study some duality transformations of the supersymmetric algebras.

  7. Electrodynamics of superconducting pnictide superlattices

    SciTech Connect (OSTI)

    Perucchi, A.; Pietro, P. Di [INSTM Udr Trieste-ST and Elettra - Sincrotrone Trieste S.C.p.A., Area Science Park, I-34012 Trieste (Italy); Capitani, F. [Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 2, I-00185 Rome (Italy); Lupi, S. [CNR-IOM and Dipartimento di Fisica, Università di Roma Sapienza, P.le Aldo Moro 2, I-00185 Roma (Italy); Lee, S.; Kang, J. H.; Eom, C. B. [Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Jiang, J.; Weiss, J. D.; Hellstrom, E. E. [Applied Superconductivity Center, National High Magnetic Field Laboratory, Florida State University, 2031 East Paul Dirac Drive, Tallahassee, Florida 32310 (United States); Dore, P. [CNR-SPIN and Dipartimento di Fisica, Università di Roma Sapienza, P.le Aldo Moro 2, I-00185 Roma (Italy)

    2014-06-02T23:59:59.000Z

    It was recently shown that superlattices where layers of the 8% Co-doped BaFe{sub 2}As{sub 2} superconducting pnictide are intercalated with non superconducting ultrathin layers of either SrTiO{sub 3} or of oxygen-rich BaFe{sub 2}As{sub 2}, can be used to control flux pinning, thereby increasing critical fields and currents, without significantly affecting the critical temperature of the pristine superconducting material. However, little is known about the electron properties of these systems. Here, we investigate the electrodynamics of these superconducting pnictide superlattices in the normal and superconducting state by using infrared reflectivity, from THz to visible range. We find that multigap structure of these superlattices is preserved, whereas some significant changes are observed in their electronic structure with respect to those of the original pnictide. Our results suggest that possible attempts to further increase the flux pinning may lead to a breakdown of the pnictide superconducting properties.

  8. The Laplace Transform 1 Laplace transform and inverse transform

    E-Print Network [OSTI]

    Yengulalp, Lynne

    The Laplace Transform Name: 1 Laplace transform and inverse transform Definition. Let f(t) be a function defined for t 0. Then the integral L {f(t)} = 0 e-st f(t)dt is said to be the Laplace transform of f provided the integral converges. Fill in the following Laplace transforms. L {tn } = L {eat } = L

  9. Superconducting magnetic energy storage for BPA transmission-line stabilization

    SciTech Connect (OSTI)

    Rogers, J.D.; Barron, M.H.; Boenig, H.J.; Criscuolo, A.L.; Dean, J.W.; Schermer, R.I.

    1982-01-01T23:59:59.000Z

    The Bonneville Power Administration (BPA) operates the electrical transmission system that joins the Pacific Northwest with southern California. A 30 MJ (8.4 kWh) Superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter is being installed at the Tacoma Substation to provide system damping for low frequency oscillations of 0.35 Hz. The integrated system status is described and reviewed. Components included in the system are the superconducting coil, seismically mounted in an epoxy fiberglass nonconducting dewar; a helium refrigerator; a heat rejection subsystem; a high pressure gas recovery subsystem; a liquid nitrogen trailer; the converter with power transformers and switchgear; and a computer system for remote microwave link operation of the SMES unit.

  10. The Funk Transform as a Penrose Transform T.N. Bailey M.G. Eastwood A.R. Gover L.J. Mason

    E-Print Network [OSTI]

    Gover, Rod

    The Funk Transform as a Penrose Transform T.N. Bailey M.G. Eastwood A.R. Gover L.J. Mason December 2, 1999 Abstract The Funk transform is the integral transform from the space of smooth even this transform as a limit in a certain sense of the Penrose transform from C P 2 to C P \\Lambda 2 . We exploit

  11. High resolution low-temperature superconductivity superconducting quantum interference device microscope for imaging magnetic fields

    E-Print Network [OSTI]

    Weiss, Benjamin P.

    -temperature superconducting niobium wire coupled to the input circuit of a superconducting quantum interference device SQUID-stated advantages of high-temperature superconductivity HTS over the more advanced low- temperature superconductivity LTS is that the higher oper- ating temperature, typically around 77 K, allows HTS SQUIDs

  12. Suppressed Superconductivity on the Surface of Superconducting RF Quality Niobium for

    E-Print Network [OSTI]

    Suppressed Superconductivity on the Surface of Superconducting RF Quality Niobium for Particle 32310, USA Abstract. Significant performance degradation of superconducting RF (radio frequency) niobium superconductivity at chemically treated RF-quality niobium. We found that pinning of vortices along GBs is weaker

  13. Chapter 54. Superconducting Circuits and Quantum Computing Superconducting Circuits and Quantum Computing

    E-Print Network [OSTI]

    Chapter 54. Superconducting Circuits and Quantum Computing 54-1 Superconducting Circuits. William D. Oliver (MIT Lincoln Laboratory Senior Staff Member, RLE affiliate) Overview: Superconducting computer. Our qubit species of choice is the superconducting persistent-current (PC) qubit (also known

  14. OUT Success Stories: The Superconductivity Partnership Initiative

    SciTech Connect (OSTI)

    Reeca, L.; Platt, C.

    2000-08-05T23:59:59.000Z

    The U.S. Department of Energy's (DOE's) Superconductivity Partnership Initiative (SPI) stands at the forefront of worldwide efforts to advance research and development of superconducting power equipment for energy transmission, distribution, and industrial use.

  15. ORNL/HTSPC-12 ORNL Superconducting Technology

    E-Print Network [OSTI]

    ORNL/HTSPC-12 ORNL Superconducting Technology Program for Electric Power Systems Annual Report States Government or any agency thereof. #12;ORNL/HTSPC-12 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM

  16. ORNL/HTSPC-18 ORNL Superconducting Technology

    E-Print Network [OSTI]

    ORNL/HTSPC-18 ORNL Superconducting Technology Program for Electric Power Systems Annual Report Government or any agency thereof. #12;ORNL/HTSPC-18 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC

  17. ORNL/HTSPC-14 ORNL Superconducting Technology

    E-Print Network [OSTI]

    ORNL/HTSPC-14 ORNL Superconducting Technology Program for Electric Power Systems Annual Report States Government or any agency thereof. #12;ORNL/HTSPC-14 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM

  18. HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01T23:59:59.000Z

    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.

  19. 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

  20. 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

  1. 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

  2. Improved superconducting magnet wire

    DOE Patents [OSTI]

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

    1983-08-16T23:59:59.000Z

    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. Superconducting Cable Termination

    DOE Patents [OSTI]

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

    2005-08-30T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Godeke, Arno

    2007-01-01T23:59:59.000Z

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

  5. Transformers Transformer device used to raise (for

    E-Print Network [OSTI]

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    Transformers Transformer ­ device used to raise (for transmission) and lower (for use) the ac with different #s of turns #12;Transformers Alternating primary current induces alternating magnetic flux in iron dt d NV B PP -= dt d NV B SS -= S S P P N V N V = #12;Transformers Transformation of voltage

  6. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

    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.

  7. A unified theory of superconductivity

    E-Print Network [OSTI]

    Xiuqing Huang

    2008-09-22T23:59:59.000Z

    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.

  8. Method and apparatus for fabricating superconducting wire

    SciTech Connect (OSTI)

    Kumar, N.

    1993-07-20T23:59:59.000Z

    A method is described for fabricating a superconducting wire comprising the steps of: in a first means, sputter depositing on a base wire a partial superconduction layer consisting of at least some, but not all, of the elements of an HTS material; and in a second means, reacting said partial superconduction layer with the other element or elements, including at least one metallic element, of the HTS material so that a complete superconduction layer is formed on said base wire.

  9. Theoretical analysis of perfect quantum state transfer with superconducting qubits

    E-Print Network [OSTI]

    Frederick W. Strauch; Carl J. Williams

    2008-12-12T23:59:59.000Z

    Superconducting quantum circuits, fabricated with multiple layers, are proposed to implement perfect quantum state transfer between nodes of a hypercube network. For tunable devices such as the phase qubit, each node can transmit quantum information to any other node at a constant rate independent of the distance between qubits. The physical limits of quantum state transfer in this network are theoretically analyzed, including the effects of disorder, decoherence, and higher-order couplings.

  10. Superconductivity and Chiral Symmetry Breaking with Fermion Clusters

    E-Print Network [OSTI]

    Shailesh Chandrasekharan

    2001-10-16T23:59:59.000Z

    Cluster variables have recently revolutionized numerical work in certain models involving fermionic variables. This novel representation of fermionic partition functions is continuing to find new applications. After describing results from a study of a two dimensional Hubbard type model that confirm a superconducting transition in the Kosterlitz-Thouless universality class, we show how a cluster type algorithm can be devised to study the chiral limit of strongly coupled lattice gauge theories with staggered fermions.

  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)

    1982-01-01T23:59:59.000Z

    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)

    1982-01-01T23:59:59.000Z

    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. ORNL/HTSPC-15 ORNL Superconducting Technology

    E-Print Network [OSTI]

    ORNL/HTSPC-15 ORNL Superconducting Technology Program for Electric Power Systems Annual Report government or any agency thereof. #12;ORNL/HTSPC-15 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC Manuscript Completed: March 2004 Date Published: June 2004 Prepared for the Superconductivity Program

  14. ORNL/HTSPC-16 ORNL Superconducting Technology

    E-Print Network [OSTI]

    ORNL/HTSPC-16 ORNL Superconducting Technology Program for Electric Power Systems Annual Report government or any agency thereof. #12;ORNL/HTSPC-16 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC ................................................................ 1-1 1.1 Ultera/ORNL HTS Cable Superconductivity Partnership with Industry (SPI

  15. 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

  16. SUPERCONDUCTING MAGNETOMETERS By J. E. MERCEREAU,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    13. SUPERCONDUCTING MAGNETOMETERS By J. E. MERCEREAU, California Institute of Technology, Alfred. P in superconducting tunnel junctions. Various structures have been fabricated in which this quantum relation dominates been the principal hallmark of the phenomena of superconductivity. It was, in fact, this effect which

  17. Flux Exclusion Superconducting Quantum Metamaterial: Towards

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Flux Exclusion Superconducting Quantum Metamaterial: Towards Quantum-level Switching V. Savinov1, they require extremely high levels of nanofabrication. Here we introduce a new quantum superconducting properties of the mac- roscopic quantum state of superconducting carriers1 , and essentially plasmonic nature

  18. Bifurcation to vortex solutions in superconducting lms

    E-Print Network [OSTI]

    Chapman, Jon

    Bifurcation to vortex solutions in superconducting #12;lms T. Boeck #3; S.J. Chapman y Mathematical state to a superconducting state in a decreasing magnetic #12;eld is studied for a slab geometry of these behaviours will occur in practice. 1 Introduction If a superconducting body is placed in a suÃ?ciently strong

  19. Measuring Hawking Radiation of a Kerr-Newman Black Hole in a Superconducting Transmission Line

    E-Print Network [OSTI]

    X. G. Lan; D. Y. Chen; L. F. Wei

    2014-03-21T23:59:59.000Z

    Applying a dimensional reduction technique and a coordinates transformation approach, we deduce the Kerr-Newman space-time into a Painlev\\'{e}-like form, and obtain its corresponding event horizon and the Hawking radiation temperature. We find that, the event horizon of a Kerr-Newman black hole can be simulated in a superconducting transmission line. Moreover, by running some numerical simulation, we confirm that the Hawking radiation of a Kerr-Newman Black Hole can be experimentally measured in a superconducting transmission line.

  20. 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)

    2010-01-12T23:59:59.000Z

    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.

  1. Free-standing oxide superconducting articles

    DOE Patents [OSTI]

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

    1993-12-14T23:59:59.000Z

    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.

  2. Computing Instantaneous Frequency by normalizing Hilbert Transform

    DOE Patents [OSTI]

    Huang, Norden E.

    2005-05-31T23:59:59.000Z

    This invention presents Normalized Amplitude Hilbert Transform (NAHT) and Normalized Hilbert Transform(NHT), both of which are new methods for computing Instantaneous Frequency. This method is designed specifically to circumvent the limitation set by the Bedorsian and Nuttal Theorems, and to provide a sharp local measure of error when the quadrature and the Hilbert Transform do not agree. Motivation for this method is that straightforward application of the Hilbert Transform followed by taking the derivative of the phase-angle as the Instantaneous Frequency (IF) leads to a common mistake made up to this date. In order to make the Hilbert Transform method work, the data has to obey certain restrictions.

  3. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

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

    1995-02-14T23:59:59.000Z

    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.

  4. Fractal Superconductivity near Localization Threshold

    E-Print Network [OSTI]

    Fominov, Yakov

    Fractal Superconductivity near Localization Threshold Mikhail Feigel'man Landau Institute, Moscow-electron states are extended but fractal and populate small fraction of the whole volume How BCS theory should be modified to account for eigenstates fractality ? #12;Mean-Field Eq. for Tc #12;#12;3D Anderson model: = 0

  5. Vacuum Technology for Superconducting Devices

    E-Print Network [OSTI]

    Chiggiato, P

    2014-01-01T23:59:59.000Z

    The basic notions of vacuum technology for superconducting applications are presented, with an emphasis on mass and heat transport in free molecular regimes. The working principles and practical details of turbomolecular pumps and cryopumps are introduced. The specific case of the Large Hadron Collider’s cryogenic vacuum system is briefly reviewed.

  6. Testability Transformation --Program Transformation to Improve Testability

    E-Print Network [OSTI]

    Binkley, David W.

    Testability Transformation -- Program Transformation to Improve Testability Mark Harman1 , Andr, 26 Richmond Street, Glasgow G1 1XH, UK. Corresponding Author. Abstract. Testability transformation. The goal is to improve the testing process by transforming a program to one that is more amenable

  7. Testability Transformation: Program Transformation to Improve Testability

    E-Print Network [OSTI]

    Singer, Jeremy

    Testability Transformation: Program Transformation to Improve Testability An Overview of Recent Author. Abstract. Testability transformation is a new form of program transfor- mation in which the goal to some chosen test adequacy criterion. The goal is to improve the testing process by transforming

  8. Superconducting nanowire single-photon detectors: physics and applications

    E-Print Network [OSTI]

    Chandra M. Natarajan; Michael G. Tanner; Robert H. Hadfield

    2012-04-25T23:59:59.000Z

    Single-photon detectors based on superconducting nanowires (SSPDs or SNSPDs) have rapidly emerged as a highly promising photon-counting technology for infrared wavelengths. These devices offer high efficiency, low dark counts and excellent timing resolution. In this review, we consider the basic SNSPD operating principle and models of device behaviour. We give an overview of the evolution of SNSPD device design and the improvements in performance which have been achieved. We also evaluate device limitations and noise mechanisms. We survey practical refrigeration technologies and optical coupling schemes for SNSPDs. Finally we summarize promising application areas, ranging from quantum cryptography to remote sensing. Our goal is to capture a detailed snapshot of an emerging superconducting detector technology on the threshold of maturity.

  9. Numerical Analysis of Non-Uniformities and Anisotropy in High-Temperature Superconducting Coils

    E-Print Network [OSTI]

    Hu, Di; Ainslie, Mark D.; Zou, Jin; Cardwell, David A.

    2014-12-12T23:59:59.000Z

    , critical current density (superconductivity), high-temperature superconductors, numerical analysis, superconducting coils, transport ac loss....

  10. Gradient limits and SCRF performance.

    SciTech Connect (OSTI)

    Norem, J.; Pellin, M.

    2007-01-01T23:59:59.000Z

    Superconducting rf gradients are limited by a number of mechanisms, among them are field emission, multipactor, Lorentz detuning, global and local heating, quench fields, Q-Slope, assembly defects, and overall power use. We describe how each of these mechanisms interacts with the cavity fields and show how significant improvements may be possible assuming improvements in control over the cavity surface. New techniques such as Atomic Layer Deposition (ALD), the use of layered composites, Gas Cluster Ion Beam (GCIB) smoothing and Dry Ice Cleaning (DIC) have been proposed as ways to control the surface.

  11. Superconducting Transitions in Wire Network under Spatially Modulated Magnetic Field

    E-Print Network [OSTI]

    Katsumoto, Shingo

    The nature of phase transition in artificially structured superconducting systems such as superconducting artificially structured superconducting systems]. Introduction of the checkerboard field with amplitude #12; to the ¼ 1=2 case lifts the double degeneracy

  12. Superconducting Tunnel Junctions as Direct Detectors for Submillimeter Astronomy

    E-Print Network [OSTI]

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

  13. Superconducting magnets for muon capture and phase rotation

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    LBNL-43998 SC-MAG-683 SUPERCONDUCTING MAGNETS FOR MUONDE-AC03-76SF00098. Green SUPERCONDUCTING MAGNETS FOR MUONet ai, "The Use of Superconducting Solenoids in a Muon

  14. anisotropic superconducting gap: Topics by E-print Network

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

    Research Laboratory of a spin-density wave SDW on s superconductivity in Fe-based superconduct- ors. We show that, contrary Vavilov, Maxim G 15 A Superconductive, Low Beta Single...

  15. 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)

    2005-03-15T23:59:59.000Z

    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.

  16. 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)

    2005-08-30T23:59:59.000Z

    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.

  17. Ten questions and answers about superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2012-11-13T23:59:59.000Z

    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.

  18. Scalable quantum computer using superconducting charge qubits

    E-Print Network [OSTI]

    W. Y. Huo; G. L. Long

    2007-06-15T23:59:59.000Z

    We present a scalable scheme for superconducting charge qubits with the assistance of one-dimensional superconducting transmission line resonator (STLR) playing the role of data bus. The coupling between qubit and data bus may be turned on and off by just controlling the gate voltage and externally applied flux of superconducting charge qubit. In our proposal, the entanglement between arbitrary two qubits and $W$ states of three qubits can be generated quickly and easily.

  19. Analyzing Signals Fourier transform

    E-Print Network [OSTI]

    Sweldens, Wim

    Page 1 1 Analyzing Signals Fourier transform s frequency content s linear combination of sin frequency analysis s windowed Fourier transform 6 #12;Page 4 7 Gabor Transform function to analyze window Gabor Transform Spatial domain Gabor domain b #12;Page 5 9 Gabor Transform Problems s discrete version

  20. Relativistic Motion with Superconducting Qubits

    E-Print Network [OSTI]

    Felicetti, S; Fuentes, I; Lamata, L; Romero, G; Solano, E

    2015-01-01T23:59:59.000Z

    We show how the dynamical modulation of the qubit-field coupling strength in a circuit quantum electrodynamics architecture mimics the motion of the qubit at relativistic speeds. This allows us to propose a realistic experiment to detect microwave photons coming from simulated acceleration radiation. Moreover, by combining this technique with the dynamical Casimir physics, we enhance the toolbox for studying relativistic phenomena in quantum field theory with superconducting circuits.

  1. Effective theory of color superconductivity

    E-Print Network [OSTI]

    Deog Ki Hong

    2007-07-17T23:59:59.000Z

    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.

  2. Superconducting magnetic energy storage (SMES) program. Progress report, January 1-December 31, 1980

    SciTech Connect (OSTI)

    Rogers, J.D. (comp.)

    1981-03-01T23:59:59.000Z

    Work is reported on the development of two superconducting magnetic energy storage (SMES) units. One is a 30-MJ unit for use by the Bonneville Power Administration (BPA) to stabilize power oscillations on their Pacific AC Intertie, and the second is a 1- to 10-GWh unit for use as a diurnal load leveling device. Emphasis has been on the stabilizing system. The manufacturing phase of the 30-MJ superconducting coil was initiated and the coil fabrication has advanced rapidly. The two converter power transformers were manufactured, successfully factory tested, and shipped. One transformer reached the Tacoma Substation in good condition; the other was dropped enroute and has been returned to the factory for rebuilding. Insulation of the 30-MJ coil has been examined for high voltage effects apt to be caused by transients such as inductive voltage spikes from the protective dump circuit. The stabilizing system converter and protective energy dump system were completed, factory tested, and delivered.

  3. Superconductive articles including cerium oxide layer

    DOE Patents [OSTI]

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

    1993-11-16T23:59:59.000Z

    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.

  4. 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)

    2014-07-21T23:59:59.000Z

    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.

  5. Superconductivity with Stripes | Advanced Photon Source

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

    between stripe order, superconductivity, and lattice structure in high-Tc superconductors was manipulated in high-pressure experiments at the APS. The physics of...

  6. Reverse circling supercurrents along a superconducting ring

    E-Print Network [OSTI]

    Tian De Cao

    2012-01-21T23:59:59.000Z

    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.

  7. DARHT Delivers Cibola Takes Flight Plutonium Superconductivity

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

    at a magnetic quantum critical point." It now appears that the cuprates, which superconduct at about 100 degrees above zero, share many of the same features as the...

  8. Superconducting Magnet Technology for Future Hadron Colliders

    E-Print Network [OSTI]

    Scanlan, R.M.

    2011-01-01T23:59:59.000Z

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

  9. New Science with the APS Superconducting Undulator

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

    | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed New Science with the APS Superconducting Undulator JULY 24, 2013 Bookmark and Share The Nature Materials cover. From...

  10. Metastable Superconducting Cuprate Phase - Energy Innovation...

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

    Electricity Transmission Find More Like This Return to Search Metastable Superconducting Cuprate Phase Brookhaven National Laboratory Contact BNL About This Technology...

  11. STATEMENT OF CONSIDERATIONS REQUEST BY DUPONT SUPERCONDUCTIVITY...

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

    its participation under the above referenced contract entitled "High Temperature Superconducting Reciprocating Magnetic Separator". This contract relates to the construction of...

  12. Superconducting Cuprates on Catalytic Substrates - Energy Innovation...

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

    Transmission Electricity Transmission Find More Like This Return to Search Superconducting Cuprates on Catalytic Substrates Brookhaven National Laboratory Contact BNL About...

  13. Towards a next theory of superconductivity

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

    measurements of doped copper-oxide superconductors are paving the way to a new theory of superconductivity," said Brad Ramshaw. EMBARGOED FOR 12 MDT March 26, 2015 Los...

  14. Dual control active superconductive devices

    DOE Patents [OSTI]

    Martens, Jon S. (Albuquerque, NM); Beyer, James B. (Madison, WI); Nordman, James E. (Madison, WI); Hohenwarter, Gert K. G. (Madison, WI)

    1993-07-20T23:59:59.000Z

    A superconducting active device has dual control inputs and is constructed such that the output of the device is effectively a linear mix of the two input signals. The device is formed of a film of superconducting material on a substrate and has two main conduction channels, each of which includes a weak link region. A first control line extends adjacent to the weak link region in the first channel and a second control line extends adjacent to the weak link region in the second channel. The current flowing from the first channel flows through an internal control line which is also adjacent to the weak link region of the second channel. The weak link regions comprise small links of superconductor, separated by voids, through which the current flows in each channel. Current passed through the control lines causes magnetic flux vortices which propagate across the weak link regions and control the resistance of these regions. The output of the device taken across the input to the main channels and the output of the second main channel and the internal control line will constitute essentially a linear mix of the two input signals imposed on the two control lines. The device is especially suited to microwave applications since it has very low input capacitance, and is well suited to being formed of high temperature superconducting materials since all of the structures may be formed coplanar with one another on a substrate.

  15. Prospects for the medium- and long-term development of China`s electric power industry and analysis of the potential market for superconductivity technology

    SciTech Connect (OSTI)

    Li, Z. [Bob Lawrence and Associates, Inc., Alexandria, VA (United States)

    1998-05-01T23:59:59.000Z

    First of all, overall economic growth objectives in China are concisely and succinctly specified in this report. Secondly, this report presents a forecast of energy supply and demand for China`s economic growth for 2000--2050. In comparison with the capability of energy construction in China in the future, a gap between supply and demand is one of the important factors hindering the sustainable development of Chain`s economy. The electric power industry is one of China`s most important industries. To adopt energy efficiency through high technology and utilizing energy adequately is an important technological policy for the development of China`s electric power industry in the future. After briefly describing the achievements of China`s electric power industry, this report defines the target areas and policies for the development of hydroelectricity and nuclear electricity in the 2000s in China, presents the strategic position of China`s electric power industry as well as objectives and relevant plans of development for 2000--2050. This report finds that with the discovery of superconducting electricity, the discovery of new high-temperature superconducting (HTS) materials, and progress in materials techniques, the 21st century will be an era of superconductivity. Applications of superconductivity in the energy field, such as superconducting storage, superconducting transmission, superconducting transformers, superconducting motors, its application in Magneto-Hydro-Dynamics (MHD), as well as in nuclear fusion, has unique advantages. Its market prospects are quite promising. 12 figs.

  16. Commissioning of the superconducting ECR ion source VENUS

    E-Print Network [OSTI]

    Leitner, Daniela; Abbott, Steve R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde; Lyneis, Claude M.

    2003-01-01T23:59:59.000Z

    COMMISSIONING OF THE SUPERCONDUCTING ECR ION SOURCE VENUS *paper describes the ongoing commissioning. Initial resultscoils [2]. During commissioning of the superconducting

  17. FORCED TWO PHASE HELIUM COOLING OF LARGE SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

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

  18. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01T23:59:59.000Z

    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 (

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

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    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

  20. A new microphonics measurement method for superconducting RF...

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

    new microphonics measurement method for superconducting RF cavities Re-direct Destination: Mechanical vibrations of the superconducting cavity, also known as microphonics, cause...

  1. applied superconductivity conference: Topics by E-print Network

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

    the High Energy Storage Ring (HESR) Index Terms--Antiproton beams, fast-ramped superconduct- ing Ohta, Shigemi 2 Presented at the Applied Superconductivity Conference at...

  2. antimatter superconducting spectrometer: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 250 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  3. aluminum-stabilized superconducting cables: Topics by E-print...

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

    are described. Hbner, K 2001-01-01 217 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  4. anisotropic superconducting ybco: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 368 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  5. advanced superconducting tokamak: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 157 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  6. aluminium stabilized superconducting: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 165 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  7. anu superconducting linac: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 367 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  8. aperture superconducting solenoid: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 349 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  9. argonne superconducting linac: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 282 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  10. apt superconducting cavities: Topics by E-print Network

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

    an example. Klingbeil, H 2011-01-01 147 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

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

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

    New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators September 12,...

  12. A Combined Near-field Scanning Microwave Microscope and Transport Measurement System for Characterizing Dissipation in Conducting and High-Tc Superconducting Films at Variable Temperature

    E-Print Network [OSTI]

    Dizon, Jonathan Reyes

    2009-04-28T23:59:59.000Z

    Identifying defects and non-superconducting regions in high-temperature superconductors (HTS) is of great importance because they limit the material's capability to carry higher current densities and serve as nucleation ...

  13. Effects of strain on the superconducting properties of niobium-tin conductors

    SciTech Connect (OSTI)

    Hoard, R.W.

    1980-11-01T23:59:59.000Z

    Investigations were performed to ascertain additional information on the connection between the cubic to tetragonal martensitic phase transformation and the phenomenon of superconductivity in Nb/sub 3/Sn. Of particular interest is the degradation of the critical parameters, such as T/sub c/, H/sub c2/, and J/sub c/, with mechanical straining of the superconductor. These studies yielded information that assisted in the derivation of the critical current-strain scaling laws mentioned above.

  14. Termination for a superconducting power transmission line including a horizontal cryogenic bushing

    DOE Patents [OSTI]

    Minati, Kurt F. (Northport, NY); Morgan, Gerry H. (Patchogue, NY); McNerney, Andrew J. (Shoreham, NY); Schauer, Felix (Upton, NY)

    1984-01-01T23:59:59.000Z

    A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminates the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.

  15. Horizontal cryogenic bushing for the termination of a superconducting power-transmission line

    DOE Patents [OSTI]

    Minati, K.F.; Morgan, G.H.; McNerney, A.J.; Schauer, F.

    1982-07-29T23:59:59.000Z

    A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminated the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.

  16. GIS TRANSFORMATIONS Conference Presentation

    E-Print Network [OSTI]

    Tobler, Waldo

    GIS TRANSFORMATIONS Conference Presentation Waldo Tobler Geography Department University, line, area, or field phenomena, then the sixteen common classes of transformation are: point -> point (scalar, vector, tensor) data, to obtain eighty distinct possible classes of transformation. The common

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

    E-Print Network [OSTI]

    Zocco, Diego Andrés

    2011-01-01T23:59:59.000Z

    3. Magnetism in Metals . . . . . . . . . . . . . . . . .IV Superconductivity and Magnetism in Iron-PnictideIII Superconductivity, Magnetism and Charge-Density Waves in

  18. SUPERCONDUCTING MAGNETS FOR A SUPER LHC T. M. Taylor*, CERN, Geneva, Switzerland

    E-Print Network [OSTI]

    Large Hadron Collider Program

    fields will be reviewed. The report will conclude with a tentative analysis of the cost issues related will be sought to increase the machine's luminosity, L, and energy, E, and thereby extend the physics reach as being a major limitation [1]. The baseline LHC machine pushes the demands on superconducting technology

  19. 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

  20. Superconductivity program for electric systems, Superconductivity Technology Center, Los Alamos National Laboratory, annual progress report for fiscal year 1997

    SciTech Connect (OSTI)

    Willis, J.O.; Newnam, B.E. [eds.; Peterson, D.E.

    1999-03-01T23:59:59.000Z

    Development of high-temperature superconductors (HTS) has undergone tremendous progress during the past year. Kilometer tape lengths and associated magnets based on BSCCO materials are now commercially available from several industrial partners. Superconducting properties in the exciting YBCO coated conductors continue to be improved over longer lengths. The Superconducting Partnership Initiative (SPI) projects to develop HTS fault current limiters and transmission cables have demonstrated that HTS prototype applications can be produced successfully with properties appropriate for commercial applications. Research and development activities at LANL related to the HTS program for Fiscal Year 1997 are collected in this report. LANL continues to support further development of Bi2223 and Bi2212 tapes in collaboration with American Superconductor Corporation (ASC) and Oxford Superconductivity Technology, Inc. (OSTI), respectively. The tape processing studies involving novel thermal treatments and microstructural characterization have assisted these companies in commercializing these materials. The research on second-generation YBCO-coated conductors produced by pulsed-laser deposition (PLD) over buffer template layers produced by ion beam-assisted deposition (IBAD) continues to lead the world. The applied physics studies of magnetic flux pinning by proton and heavy ion bombardment of BSCCO and YBCO tapes have provided many insights into improving the behavior of these materials in magnetic fields. Sections 4 to 7 of this report contain a list of 29 referred publications and 15 conference abstracts, a list of patent and license activities, and a comprehensive list of collaborative agreements in progress and completed.

  1. Free-standing oxide superconducting articles

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

    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).

  2. STRIPES AND SUPERCONDUCTIVITY IN CUPRATE SUPERCONDUCTORS

    SciTech Connect (OSTI)

    TRANQUADA, J.M.

    2005-08-22T23:59:59.000Z

    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.

  3. SUPERCONDUCTING MAGNET NEEDS FOR THE ILC.

    SciTech Connect (OSTI)

    PARKER,B.; TOMPKINS, J.C.; KASHIKHIN, VI.; PALMER, M.A.; CLARKE, J.A.

    2007-06-25T23:59:59.000Z

    The ILC Reference Design Report was completed early in February 2007. The Magnet Systems Group was formed to translate magnetic field requirements into magnet designs and cost estimates for the Reference Design. As presently configured, the lLC will have more than 13,000 magnetic elements of which more than 2300 will be based on superconducting technology. This paper will describe the major superconducting magnet needs for the ILC as presently determined by the Area Systems Groups, responsible for beam line design, working with the Magnet Systems Group. The superconducting magnet components include Main Linac quadrupoles, Positron Source undulators, Damping Ring wigglers, a complex array of Final Focus superconducting elements in the Beam Delivery System, and large superconducting solenoids in the e{sup +} and e{sup -} Sources, and the Ring to Main Linac lines.

  4. Superconducting magnet needs for the ILC

    SciTech Connect (OSTI)

    Tompkins, J.C.; Kashikhin, Vl.; /Fermilab; Parker, B.; /Brookhaven; Palmer, M.A. /; Clarke, J.A.; /Daresbury

    2007-06-01T23:59:59.000Z

    The ILC Reference Design Report was completed early in February 2007. The Magnet Systems Group was formed to translate magnetic field requirements into magnet designs and cost estimates for the Reference Design. As presently configured, the ILC will have more than 13,000 magnetic elements of which more than 2300 will be based on superconducting technology. This paper will describe the major superconducting magnet needs for the ILC as presently determined by the Area Systems Groups, responsible for beam line design, working with the Magnet Systems Group. The superconducting magnet components include Main Linac quadrupoles, Positron Source undulators, Damping Ring wigglers, a complex array of Final Focus superconducting elements in the Beam Delivery System, and large superconducting solenoids in the e{sup +} and e{sup -} Sources, and the Ring to Main Linac lines.

  5. Superconducting DC and RF Properties of Ingot Niobium

    E-Print Network [OSTI]

    Dhakal, Pashupati; Kneisel, Peter; Myneni, Ganapati Rao

    2012-01-01T23:59:59.000Z

    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 TE011 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.

  6. Model Transformations Require Formal Semantics Zekai Demirezen, 2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Model Transformations Require Formal Semantics 1 Yu Sun, 1 Zekai Demirezen, 2 Tomaz Lukman, 3 limitations of model transformation, with a specific emphasis on model optimization. A primary shortcoming that can be found in many model transformation approaches and tools is the lack of formal semantics

  7. Microelectronic superconducting crossover and coil

    DOE Patents [OSTI]

    Wellstood, Frederick C. (Berkeley, CA); Kingston, John J. (Oakland, CA); Clarke, John (Berkeley, CA)

    1994-01-01T23:59:59.000Z

    A microelectronic component comprising a crossover is provided comprising a substrate, a first high T.sub.c superconductor thin film, a second insulating thin film comprising SrTiO.sub.3 ; and a third high T.sub.c superconducting film which has strips which crossover one or more areas of the first superconductor film. An in situ method for depositing all three films on a substrate is provided which does not require annealing steps and which can be opened to the atmosphere between depositions.

  8. Fermionic Models with Superconducting Circuits

    E-Print Network [OSTI]

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

    2015-03-31T23:59:59.000Z

    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

    2015-06-26T23:59:59.000Z

    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

    2012-01-30T23:59:59.000Z

    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. Microelectronic superconducting crossover and coil

    DOE Patents [OSTI]

    Wellstood, F.C.; Kingston, J.J.; Clarke, J.

    1994-03-01T23:59:59.000Z

    A microelectronic component comprising a crossover is provided comprising a substrate, a first high T[sub c] superconductor thin film, a second insulating thin film comprising SrTiO[sub 3]; and a third high T[sub c] superconducting film which has strips which crossover one or more areas of the first superconductor film. An in situ method for depositing all three films on a substrate is provided which does not require annealing steps and which can be opened to the atmosphere between depositions. 13 figures.

  12. Fermionic Models with Superconducting Circuits

    E-Print Network [OSTI]

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

    2014-11-10T23:59:59.000Z

    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.

  13. transformation languages Introduction

    E-Print Network [OSTI]

    Nierstrasz, Oscar

    transformation languages Introduction Transformation languages are widely used for to process can I change / transform the design of a certain task without changing it's logic The common/and hierarchical or/and abstract set of information. It can even be a stream of data. · The transformation engine

  14. Glowing Bacteria: Transformation Efficiency

    E-Print Network [OSTI]

    Rose, Michael R.

    1 Glowing Bacteria: Transformation Efficiency Purpose: To determine how well your E. coli cells took up and expressed GFP after transformation. Background: Transformation efficiency is a quantitative)______ (Fraction of DNA spread on plate) = ______ µg plasmid DNA spread on plate #12;2 5. Transformation efficiency

  15. Learning Transformations From Video

    E-Print Network [OSTI]

    Wang, Ching Ming

    2010-01-01T23:59:59.000Z

    on Natural Video . . . . . . . . . . . . . . . . .3 Learning Continuous Transformation from VideoProposed Video Coder

  16. Spectral measurement of the thermal excitation of a superconducting qubit

    E-Print Network [OSTI]

    Boyer, Edmond

    Spectral measurement of the thermal excitation of a superconducting qubit A. Palacios-Laloy, F of a superconducting qubit 2 Superconducting qubits [1] are promising candidates for implementing a solid- state lying in their ground state. In most superconducting qubit experiments, the initialization is simply

  17. 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

  18. 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)

    1999-01-01T23:59:59.000Z

    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).

  19. Magnetohydrodynamics in Superconducting-Superfluid Neutron Stars

    E-Print Network [OSTI]

    Gregory Mendell

    1997-09-09T23:59:59.000Z

    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.

  20. Toward a Holographic Model of Superconducting Fermions

    E-Print Network [OSTI]

    Andy O'Bannon

    2008-11-02T23:59:59.000Z

    We use the AdS/CFT correspondence to study N=4 supersymmetric SU(Nc) Yang-Mills theory, in the limits of large Nc and large 't Hooft coupling, coupled to a number Nf of massless hypermultiplet fields in the fundamental representation of the gauge group. We identify a U(1) subgroup of the R-symmetry under which the fermions in the hypermultiplet are charged but the scalars are not. All the hypermultiplet fields are also charged under a U(1) baryon number symmetry. We introduce an external magnetic field for the baryon number U(1), which triggers the spontaneous breaking of the U(1) R-symmetry, and we then introduce a chemical potential for the U(1) R-charge, producing a state with a nonzero density of the U(1) R-charge. The system should then exhibit superconductivity of the U(1) R-charge. The dual supergravity description is a number Nf of D7-branes in AdS5 x S5 with angular momentum on the S5 and a worldvolume magnetic field. We study the zero-temperature thermodynamics of the system, and find that for sufficiently large magnetic field the system prefers to be in the symmetry-broken phase. For smaller magnetic fields we find a discontinuous free energy, indicating that our gravitational setup does not capture all equilibrium states of the field theory.

  1. High Temperature Superconducting Underground Cable

    SciTech Connect (OSTI)

    Farrell, Roger, A.

    2010-02-28T23:59:59.000Z

    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.

  2. Perfect NOT transformation and conjugate transformation

    E-Print Network [OSTI]

    Fengli Yan; Ting Gao; Zhichao Yan

    2012-03-15T23:59:59.000Z

    The perfect NOT transformation, probabilistic perfect NOT transformation and conjugate transformation are studied. Perfect NOT transformation criteria on a quantum state set $S$ of a qubit are obtained. Two necessary and sufficient conditions for realizing a perfect NOT transformation on $S$ are derived. When these conditions are not satisfied we discuss a probabilistic perfect NOT transformation (gate). We construct a probabilistic perfect NOT machine (gate) by a general unitary-reduction operation. With a postselection of the measurement outcomes, the probabilistic NOT gate yields perfectly complements of the input states. We prove that one can realize probabilistically the NOT gate of the input states secretly chosen from a certain set $S=\\{|\\Psi_1>, |\\Psi_2>,..., |\\Psi_n>\\}$ if and only if $|\\Psi_1>, |\\Psi_2>,...,$ and $|\\Psi_n>$ are linearly independent. We also generalize the probabilistic NOT transformation to the conjugate transformation in the multi-level quantum system. The lower bound of the best possible efficiencies attained by a probabilistic perfect conjugate transformation are obtained.

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

    E-Print Network [OSTI]

    Myers, Michael James

    2010-01-01T23:59:59.000Z

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

  4. Fabrication of a Short-Period Nb3Sn Superconducting Undulator

    E-Print Network [OSTI]

    Dietderich, Daniel

    2008-01-01T23:59:59.000Z

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

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

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

  8. antibodies successes limitations: Topics by E-print Network

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

    the effects of harmonics on their systems: telephone noise, excessive heating of transformers and other equipment, capacitor damage, and others, and would like to limit the...

  9. Superconducting wire and cable for RHIC

    SciTech Connect (OSTI)

    Garber, M.; Ghosh, A.K.; Greene, A.; McChesney, D.; Morgillo, A.; Shah, R. [Brookhaven National Lab., Upton, NY (United States); DelRe, S.; Epstein, G.; Hong, S.; Lichtenwalner, J. [Oxford Superconducting Technology, Carteret, NJ (United States)] [and others

    1994-06-01T23:59:59.000Z

    The superconducting dipole and quadrupole magnets in the RHIC accelerator ring are to be fabricated from 30-strand superconducting cable. The RHIC wire has a diameter of 0.65 mm, copper-to-superconductor ratio of 2.25, filament diameter of 6 {mu}m and high critical current density. Primary emphasis during manufacturing has been on uniformity of materials, processes and performance. Near final results are presented on a production program which has extended over two years. Measured parameters are described which are important for design of superconducting accelerator magnets.

  10. Higher Order Mode Heating Analysis for the ILC Superconducting Linacs

    SciTech Connect (OSTI)

    Bane, K.L.F.; Nantista, C.; Adolphsen, C.; /SLAC; ,

    2010-10-27T23:59:59.000Z

    The superconducting cavities and interconnects in the 11 km long linacs of the International Linear Collider (ILC) are designed to operate at 2K, where cooling costs are very expensive. It is thus important to minimize cryogenic heat loads. In addition to an unavoidable static load and the dynamic load of the fundamental 1.3 GHz accelerating rf, a further heat source is presented by the higher order mode (HOM) power deposited by the beam. Such modes will be damped by specially designed HOM couplers attached to the cavities (for trapped modes), and by ceramic dampers at 70K that are located between the eight or nine cavity cryomodules (for propagating modes). Brute force calculation of the higher frequency modes excited in a string of cryomodules is limited by computing capacity (see, e.g. [1]). M. Liepe has calculated {approx} 400 longitudinal TM modes in 3 superconducting cavities plus absorbers, up to 8 GHz [2]. Joestingmeier, et al., have used a ray tracing calculation to find the effect at higher frequencies, specifically in the range of tens of GHz and above [3]. In this report we present a scattering matrix approach, which we apply to an rf unit comprising 26 cavities and 3 absorbers. We perform calculations at sample frequencies (up to 20 GHz) to predict the effectiveness of the ceramic dampers in limiting HOM heat deposition at 2K.

  11. Gapless superconductivity and string theory

    E-Print Network [OSTI]

    Sergei Khlebnikov

    2014-11-06T23:59:59.000Z

    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.

  12. Subranging technique using superconducting technology

    DOE Patents [OSTI]

    Gupta, Deepnarayan (Hawthorne, NY)

    2003-01-01T23:59:59.000Z

    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.

  13. High Transformer ratios in collinear wakefield accelerators.

    SciTech Connect (OSTI)

    Power, J. G.; Conde, M.; Yusof, Z.; Gai, W.; Jing, C.; Kanreykin, A.; Schoessow, P.; High Energy Physics; Euclid Techlabs, LLC

    2008-01-01T23:59:59.000Z

    Based on our previous experiment that successfully demonstrated wakefield transformer ratio enhancement in a 13.625 GHz dielectric-loaded collinear wakefield accelerator using the ramped bunch train technique, we present here a redesigned experimental scheme for even higher enhancement of the efficiency of this accelerator. Design of a collinear wakefield device with a transformer ratio R2, is presented. Using a ramped bunch train (RBT) rather than a single drive bunch, the enhanced transformer ratio (ETR) technique is able to increase the transformer ratio R above the ordinary limit of 2. To match the wavelength of the fundamental mode of the wakefield with the bunch length (sigmaz=2 mm) of the new Argonne wakefield accelerator (AWA) drive gun (where the experiment will be performed), a 26.625 GHz dielectric based accelerating structure is required. This transformer ratio enhancement technique based on our dielectric-loaded waveguide design will result in a compact, high efficiency accelerating structures for future wakefield accelerators.

  14. Magnetic fluctuations and heavy electron superconductivity

    SciTech Connect (OSTI)

    Norman, M.R.

    1988-01-01T23:59:59.000Z

    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.

  15. Degreasing and cleaning superconducting RF Niobium cavities

    SciTech Connect (OSTI)

    Rauchmiller, Michael; Kellett, Ron; /Fermilab

    2011-09-01T23:59:59.000Z

    The purpose and scope of this report is to detail the steps necessary for degreasing and cleaning of superconducting RF Niobium cavities in the A0 clean room. It lists the required equipment and the cleaning procedure.

  16. Superconducting RF Injector T. Srinivasan-Rao

    E-Print Network [OSTI]

    current injector Heat LossRF Requirements Superconducting injector Photocathode Cesium Telluride Nb(degrees) Cooled to 4 K. Undercoupled Frequency: ~1301.5727 MHz, Loaded Q:~1x107-Contaminants effect? Freq. Vs

  17. Cooling arrangement for a superconducting coil

    DOE Patents [OSTI]

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

    1998-06-30T23:59:59.000Z

    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.

  18. Operational experience with superconducting synchrotron magnets

    SciTech Connect (OSTI)

    Martin, P.S.

    1987-03-01T23:59:59.000Z

    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.

  19. Superconducting technology program Sandia 1996 annual report

    SciTech Connect (OSTI)

    Roth, E.P.

    1997-02-01T23:59:59.000Z

    Sandia`s Superconductivity Technology Program is a thallium-based high-temperature superconductor (HTS) research and development program consisting of efforts in powder synthesis and process development, open-system thick film conductor development, wire and tape fabrication, and HTS motor design. The objective of this work is to develop high-temperature superconducting conductors (wire and tape) capable of meeting requirements for high-power electrical devices of interest to industry. The research efforts currently underway are: (1) Process development and characterization of thallium-based high-temperature superconducting closed system wire and tape, (2) Investigation of the synthesis and processing of thallium-based thick films using two-zone processing, and (3) Cryogenic design of a 30K superconducting motor. This report outlines the research that has been performed during FY96 in each of these areas.

  20. Superconductivity for electric power systems: Program overview

    SciTech Connect (OSTI)

    Not Available

    1995-02-01T23:59:59.000Z

    Largely due to government and private industry partnerships, electric power applications based upon high-temperature superconductivity are now being designed and tested only seven years after the discovery of the high-temperature superconductors. These applications offer many benefits to the national electric system including: increased energy efficiency, reduced equipment size, reduced emissions, increased stability/reliability, deferred expansion, and flexible electricity dispatch/load management. All of these benefits have a common outcome: lower electricity costs and improved environmental quality. The U.S. Department of Energy (DOE) sponsors research and development through its Superconductivity Program for Electric Power Systems. This program will help develop the technology needed for U.S. industries to commercialize high-temperature superconductive electric power applications. DOE envisions that by 2010 the U.S. electric power systems equipment industry will regain a major share of the global market by offering superconducting products that outperform the competition.

  1. Coupling light to superconductive photon counters

    E-Print Network [OSTI]

    Hu, Xiaolong

    2008-01-01T23:59:59.000Z

    Superconductive nanowire single-photon detectors (SNSPDs) are an emerging, ultrasensitive photon counting technology which may enable fiber-based, long-haul quantum key distribution. Our group has successfully developed a ...

  2. 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...

  3. Near-zero modes in superconducting graphene

    E-Print Network [OSTI]

    Ghaemi, Pouyan

    Vortices in the simplest superconducting state of graphene contain very-low-energy excitations whose existence is connected to an index theorem that applies strictly to an approximate form of the relevant Bogoliubov–de ...

  4. Complex States, Emergent Phenomena & Superconductivity in Intermetalli...

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

    could be made without rare earths. Crossing Over from "Normal" to "Superconducting" A new ultra-fast laser technique has yielded insights into how iron arsenide materials evolve to...

  5. Metrics for enterprise transformation

    E-Print Network [OSTI]

    Blackburn, Craig D. (Craig David), S. M. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    The objective of this thesis is to depict the role of metrics in the evolving journey of enterprise transformation. To this end, three propositions are explored: (i) metrics and measurement systems drive transformation, ...

  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)

    2002-01-01T23:59:59.000Z

    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. Lattice Vibrations and Superconductivity in Layered Structures

    E-Print Network [OSTI]

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

    1970-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 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 to estimate the influence of both surface and interface effects on phonon frequencies and superconducting transition temperatures in layered structures, we have calculated the vibrational modes of structures composed...

  8. Architecture for high critical current superconducting tapes

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

    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.

  9. Evaluating Transformer Losses

    E-Print Network [OSTI]

    Grun, R. L. Jr.

    therefore are a function of the load squared. No-load losses occur from energizing the transformer steel and fore are continuous regardless of the transformer load. TRANSFORMER DESIGN Both types of losses are a fun ce here ion of design. If losses...

  10. Spacetime transformation acoustics

    E-Print Network [OSTI]

    C. García-Meca; S. Carloni; C. Barceló; G. Jannes; J. Sánchez-Dehesa; A. Martínez

    2014-07-08T23:59:59.000Z

    A recently proposed analogue transformation method has allowed the extension of transformation acoustics to general spacetime transformations. We analyze here in detail the differences between this new analogue transformation acoustics (ATA) method and the standard one (STA). We show explicitly that STA is not suitable for transformations that mix space and time. ATA takes as starting point the acoustic equation for the velocity potential, instead of that for the pressure as in STA. This velocity-potential equation by itself already allows for some transformations mixing space and time, but not all of them. We explicitly obtain the entire set of transformations that do not leave its form invariant. It is in these cases that ATA shows its true potential, allowing for building a transformation acoustics method that enables the full range of spacetime transformations. We provide an example of an important transformation which cannot be achieved with STA. Using this transformation, we design and simulate an acoustic frequency converter via the ATA approach. Furthermore, in those cases in which one can apply both the STA and ATA approaches, we study the different transformational properties of the corresponding physical quantities.

  11. LAPPED TRANSFORMS COMPRESSION

    E-Print Network [OSTI]

    de Queiroz, Ricardo L.

    Chapter 6 LAPPED TRANSFORMS FOR IMAGE COMPRESSION Ricardo L. de Queiroz Digital Imaging Technology aspects of lapped transforms and their applications to image compression. It is a subject that has been extensively studied mainly because lapped transforms are closely related to filter banks, wavelets, and time

  12. ASC 84: applied superconductivity conference. Final program and abstracts

    SciTech Connect (OSTI)

    Not Available

    1984-01-01T23:59:59.000Z

    Abstracts are given of presentations covering: superconducting device fabrication; applications of rf superconductivity; conductor stability and losses; detectors and signal processing; fusion magnets; A15 and Nb-Ti conductors; stability, losses, and various conductors; SQUID applications; new applications of superconductivity; advanced conductor materials; high energy physics applications of superconductivity; electronic materials and characterization; general superconducting electronics; ac machinery and new applications; digital devices; fusion and other large scale applications; in-situ and powder process conductors; ac applications; synthesis, properties, and characterization of conductors; superconducting microelectronics. (LEW)

  13. 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

    2009-11-10T23:59:59.000Z

    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.

  14. MATHEMATICAL ANALYSIS OF CONDUCTING AND SUPERCONDUCTING TRANSMISSION LINES

    E-Print Network [OSTI]

    Ramdani, Karim - Institut de Mathématiques �lie Cartan, Université Henri Poincaré

    MATHEMATICAL ANALYSIS OF CONDUCTING AND SUPERCONDUCTING TRANSMISSION LINES ANNE-SOPHIE BONNET propagation in the microstrip transmission lines used in microelectronics. In the first part, the case of the perfectly conducting strip. Key words. superconducting transmission lines, waveguides, spectral analysis

  15. Superconducting magnets for muon capture and phase rotation

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    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

  16. Spontaneous Emission Near Superconducting Bodies

    E-Print Network [OSTI]

    Bo-Sture K. Skagerstam; Per Kristian Rekdal

    2007-06-07T23:59:59.000Z

    In the present paper we study the spontaneous photon emission due to a magnetic spin-flip transition of a two-level atom in the vicinity of a dielectric body like a normal conducting metal or a superconductor. For temperatures below the transition temperature T_c of a superconductor, the corresponding spin-flip lifetime is boosted by several orders of magnitude as compared to the case of a normal conducting body. Numerical results of an exact formulation are also compared to a previously derived approximative analytical expression for the spin-flip lifetime and we find an excellent agreement. We present results on how the spin-flip lifetime depends on the temperature T of a superconducting body as well as its thickness H. Finally, we study how non-magnetic impurities as well as possible Eliashberg strong-coupling effects influence the spin-flip rate. It is found that non-magnetic impurities as well as strong-coupling effects have no dramatic impact on the spin-flip lifetime.

  17. BNL Direct Wind Superconducting Magnets

    SciTech Connect (OSTI)

    Parker, B.; Anerella, M.; Escallier, J.; Ghosh, A.; Jain, A.; Marone, A.; Muratore, A.; Wanderer, P.

    2011-09-12T23:59:59.000Z

    BNL developed Direct Wind magnet technology is used to create a variety of complex multi-functional multi-layer superconducting coil structures without the need for creating custom production tooling and fixturing for each new project. Our Direct Wind process naturally integrates prestress into the coil structure so external coil collars and yokes are not needed; the final coil package transverse size can then be very compact. Direct Wind magnets are produced with very good field quality via corrections applied during the course of coil winding. The HERA-II and BEPC-II Interaction Region (IR) magnet, J-PARC corrector and Alpha antihydrogen magnetic trap magnets and our BTeV corrector magnet design are discussed here along with a full length ILC IR prototype magnet presently in production and the coils that were wound for an ATF2 upgrade at KEK. A new IR septum magnet design concept for a 6.2 T combined-function IR magnet for eRHIC, a future RHIC upgrade, is introduced here.

  18. Electronic high voltage generator with a high temperature superconducting coil

    SciTech Connect (OSTI)

    Jin, J.X.; Liu, H.K.; Dou, S.X. [Univ. of Wollongong (Australia)] [and others

    1996-12-31T23:59:59.000Z

    A novel method for generating high voltages from a low voltage DC source, by using a capacitor and inductor in a R, L, C resonant circuit has been developed with the consideration of using a high temperature superconducting (HTS) coil. To generate high voltages the polarity of a low voltage battery source is reversed each half resonant cycle, the control being achieved by an electronic switch. Resistance in the circuit limits the voltages that can be built up. By replacing a copper winding inductor with another inductor which has a HTS winding, the magnitude of achievable voltages is substantially increased. A (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+x} multifilament HTS wire is considered in this work to make the superconducting inductor. The high voltages generated are not capable of supplying low impedance loads, however, possible applications of the generator include electrical partial discharge testing and insulation resistance testing. It could also be used as a testing method for the HTS itself with respect to the critical current and AC loss measurement.

  19. Quantification of disturbance energy due to conductor motion and stability analysis of superconducting composite wire

    SciTech Connect (OSTI)

    Tsukamoto, O.; Takao, T.; Honjo, S.

    1989-03-01T23:59:59.000Z

    One of the most intricate disturbances causing quenches in high-current-density superconducting magnets is an abrupt conductor motion. There have been very few papers investigating the disturbance energy of the conductor motion and its generally understood that its quantification is very difficult. The authors have proposed a model to quantify the disturbance energy due to conductor motion. The model relates the disturbance energy to mechanical properties of a conductor, electromagnetic force and winding structure. In the paper, stability of a superconducting composite conductor subject to an abrupt conductor motion is analyzed based on the proposed model. It is pointed out that the stability of the conductor is improved by decreasing distance between spacers placed between the conductors. However, it is also pointed out that there is a limit to the improvement of the stability of decreasing the spacer distance, because of limited accuracies of the conductor and spacer dimensions.

  20. Self-recovering superconducting strip detectors

    SciTech Connect (OSTI)

    Gabutti, A.; Gray, K.E.

    1991-09-01T23:59:59.000Z

    Using a 1.8 {mu}m wide superconducting strip made of granular tungsten, we have observed self-recovering pulses when the detector is irradiated with a {sup 55}Fe 6 keV X-rays source. For low values of the bias current (i.e. I{sub b}<30{mu}A at T{sub b}=1.5K) the superconducting state is recovered in 10--50 ns giving voltage pulses across the strip of few hundred {mu}v in amplitude. At high bias currents the detector did not self-recover and a constant counting efficiency has measured at different operating temperatures. There are good indications that this high counting rate can be extended to all the reduced bias currents where the detector is able to reset itself after every switch. The current threshold between collapsing and propagating switches and the time evolution of the voltage pulses can be described using a thermal propagation model developed in previous works. The ability of detectors to automatically recover the superconducting state in a short period of time after sensing a particle is encouraging in the feasibility study of fast superconducting microvertex detectors and also confirm the potential application of superconducting strips as high fast resolution X-rays detectors.

  1. High Temperature Superconductivity in Cuprates: a model

    E-Print Network [OSTI]

    P. R. Silva

    2010-07-16T23:59:59.000Z

    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.

  2. Color superconductivity and dense quark matter

    E-Print Network [OSTI]

    Massimo Mannarelli

    2008-12-26T23:59:59.000Z

    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.

  3. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01T23:59:59.000Z

    the MICE cooling channel magnets and the progress in theProgress on the Superconducting Magnets for the MICE Cooling

  4. Towards Computing Ratcheting and Training in Superconducting Magnets

    E-Print Network [OSTI]

    Ferracin, Paolo

    2009-01-01T23:59:59.000Z

    Towards Computing Ratcheting and Training in Superconductingcomputational results of the ratcheting process, the impactright). Index Terms—Ratcheting, superconducting magnet,

  5. Large power transformers

    SciTech Connect (OSTI)

    Karsai, K.; Kerenyi, D.; Kiss, L.

    1987-01-01T23:59:59.000Z

    The book deals with the following aspects of transformer engineering: general principles governing the function of transformers, iron cores, windings, stray losses caused by stray flux, the insulation of transformers, and the structural parts and accessories. This edition includes the developments in theory and practice on the basis of the authors' experience in design, manufacturing and testing of large transformers. New developments have been particularly extensive in the fields of new magnetic materials, cooling methods, dielectric strength for overvoltages of different types, and stray-load loss problems, which are presented in the book in detail. The many diagrams in the book can be used directly in the design, manufacture and testing of large transformers. In preparing their text, the authors have aimed to satisfy the demand for a work that summarizes the latest experience in development and design of large power transformers.

  6. Plant and operational features of the BPA 30 MJ superconducting magnetic energy storage system

    SciTech Connect (OSTI)

    Rogers, J.D.; Hauer, J.F.

    1984-01-01T23:59:59.000Z

    A 30 MJ superconducting magnetic energy storage (SMES) system was designed and developed for application in the Western US Power System to damp power oscillations that limit high voltage ac transmission. The system is in place at the Bonneville Power Administration (BPA) Tacoma Substation and has been in an experimental use for over a year. Extended operations of the unit have been undertaken with success. The physical, electrical, and operational features of the SMES system are given.

  7. Study on the energy criterion of cuprate superconductivity

    E-Print Network [OSTI]

    Gu Jiapu

    2010-02-09T23:59:59.000Z

    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.

  8. The millimeter-wave properties of superconducting microstrip lines

    E-Print Network [OSTI]

    The millimeter-wave properties of superconducting microstrip lines A. Vayonakis£, C. Luo , H of the millimeter-wave properties of superconducting thin-film microstrip transmission lines. Our exper- imental, with a temperature-independent loss tangent of 5 3 ¦0 5 ¢10 3 for our samples. INTRODUCTION Superconducting

  9. October 1988 SUPERCONDUCTING CAVITIES IN THE LIGHT SOURCE STORAGE RING

    E-Print Network [OSTI]

    Kemner, Ken

    LS-86 T. K. Khoe October 1988 SUPERCONDUCTING CAVITIES IN THE LIGHT SOURCE STORAGE RING superconducting cavities. Several laboratories (CERN, KEK, DESY) are making definite plans to use them the problem of multipactoring. The main problems of using superconducting cavities in "high current" storage

  10. 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

  11. 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

  12. Design of a Superconducting Quantum Computer Prof. John Martinis

    E-Print Network [OSTI]

    Rimon, Elon

    Design of a Superconducting Quantum Computer Prof. John Martinis University of California Date building (Faculty of Materials Science and Engineering) #12;Design of a Superconducting Quantum Computer Superconducting quantum computing is now at an important crossroad, where "proof of concept" experiments involving

  13. Non-Abelian Superconducting Pumps Valentina Brosco,1,2

    E-Print Network [OSTI]

    Joye, Alain

    Non-Abelian Superconducting Pumps Valentina Brosco,1,2 Rosario Fazio,3,4 F. W. J. Hekking,5 for the adiabatic pumped charge in superconducting nanocircuits in the presence of level degeneracy and relate,10]. If only superconducting leads are present pumping is due to the adiabatic transport of Cooper pairs

  14. 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

  15. A model for variable thickness superconducting thin lms

    E-Print Network [OSTI]

    Chapman, Jon

    A model for variable thickness superconducting thin #12;lms S. J. Chapman #3; Mathematical for Applied Mathematics Virginia Tech Blacksburg VA 24061-0531, USA Abstract A model for superconductivity. When the #12;lm is of uniform thickness the model is identical to a model for superconducting cylinders

  16. Superconducting Properties MgB 2 from First Principles

    E-Print Network [OSTI]

    Gross, E.K.U.

    Superconducting Properties MgB 2 from First Principles Floris, Profeta, Lathiotakis, 1 LuË?ders, 4 M, such very high superconducting transition temperature. Focusing on compound, report first nontrivial.25.Jb, 71.15.Mb, -- 74.70.Ad Understanding and predicting superconducting proper­ ties real materials

  17. Entanglement and Quantum Error Correction with Superconducting Qubits

    E-Print Network [OSTI]

    Entanglement and Quantum Error Correction with Superconducting Qubits A Dissertation Presented David Reed All rights reserved. #12;Entanglement and Quantum Error Correction with Superconducting is to use superconducting quantum bits in the circuit quantum electro- dynamics (cQED) architecture. There

  18. Fig. 1. Schematic of LDX device showing three superconducting

    E-Print Network [OSTI]

    1 Fig. 1. Schematic of LDX device showing three superconducting magnets and the plasma@psfc.mit.edu Abstract: We report the first production of high beta plasma confined by a laboratory superconducting-field superconducting dipole magnet, termed the "floating coil" was supported by three thin support rods. In this mode

  19. Grid Transformation Workshop

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

    3-03-Grid-Transformation-Workshop Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us Projects & Initiatives Expand Projects &...

  20. Superconducting technology program: Sandia 1995 annual report

    SciTech Connect (OSTI)

    Roth, E.P. [Sandia National Labs., Albuquerque, NM (United States). Superconductivity Materials and Technology Dept.

    1996-03-01T23:59:59.000Z

    Sandia`s STP program is a thallium-based high-temperature superconductor (HTS) research and development program consisting of efforts in powder synthesis and process development, open-system thick film conductor development, wire and tape fabrication, and HTS motor design. The objective of this work is to develop high-temperature superconducting conductors (wire and tape) capable of meeting requirements for high-power electrical devices of interest to industry. The research efforts currently underway are: (1) process development and characterization of thallium-based high-temperature superconducting closed system wire and tape; (2) investigation of the synthesis and processing of thallium-based thick films using two-zone processing; and (3) cryogenic design of a 30K superconducting motor. This report outlines the research that has been performed during FY95 in each of these areas.

  1. Improved Superconducting Wire for Wind Generators: Superconducting Wires for Direct-Drive Wind Generators

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    REACT Project: Brookhaven National Laboratory will develop a low-cost superconducting wire that could be used in high-power wind generators. Superconducting wire currently transports 600 times more electric current than a similarly sized copper wire, but is significantly more expensive. Brookhaven National Laboratory will develop a high-performance superconducting wire that can handle significantly more electrical current, and will demonstrate an advanced manufacturing process that has the potential to yield a several-fold reduction in wire costs while using a using negligible amount of rare earth material. This design has the potential to make a wind turbine generator lighter, more powerful, and more efficient, particularly for offshore applications.

  2. Proposed Giaever transformer to probe the pseudogap phase of cuprates.

    SciTech Connect (OSTI)

    Levchenko, A.; Norman, M. R. (Materials Science Division)

    2011-03-01T23:59:59.000Z

    We develop a theory of the rectification effect in a double-layer system where both layers are superconductors or one of the layers is a normal metal. The Coulomb interaction is assumed to provide the dominant coupling between the layers. We find that superconducting fluctuations strongly enhance the drag conductivity, with rectification most pronounced when both layers are superconductors. In view of their distinct dependence on temperature near T{sub c} and layer separation, drag measurements based on a Giaever transformer could distinguish whether rectification occurs due to fluctuating pairs or inductively coupled fluctuating vortices.

  3. Direct observation of superconducting vortex clusters pinned by a periodic array of magnetic dots in ferromagnetic/superconducting hybrid structures

    E-Print Network [OSTI]

    Metlushko, Vitali

    Direct observation of superconducting vortex clusters pinned by a periodic array of magnetic dots in ferromagnetic/superconducting hybrid structures T. Shapoval,1,* V. Metlushko,2 M. Wolf,1 B. Holzapfel,1 V. Neu,1, Illinois 60612, USA Received 13 November 2009; published 11 March 2010 Strong pinning of superconducting

  4. 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.

    2002-01-01T23:59:59.000Z

    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.

  5. Recent Developments in High Temperature Superconductivity

    E-Print Network [OSTI]

    Hor, P. H.

    -Ca-Ba-Cu-O (TCBCO) [5] have been found to be superconducting at as high at 125K in TCBCO. Superconductivity up to - 30K has also been found in the Ba-K-Bi-O type perovskite system [6,7]. Without a copper-oxygen planar structure involved, this system offers a...Can-1 Cu n 04+2n where A =Bi or Tl and B =Ba or Sr and n is the number of CU-O layers stacked consecutively in the unit cell. For the BCSCO and TCBCO compound series, they all have layers of perovskite-like structures (with n =1, 2, or 3...

  6. On Testing Entropic Inequalities for Superconducting Qudit

    E-Print Network [OSTI]

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

    2015-05-20T23:59:59.000Z

    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.

  7. Realization of a superconducting atom chip

    E-Print Network [OSTI]

    Thomas Nirrengarten; Angie Qarry; Cédric Roux; Andreas Emmert; Gilles Nogues; Michel Brune; Jean-Michel Raimond; Serge Haroche

    2006-10-09T23:59:59.000Z

    We have trapped rubidium atoms in the magnetic field produced by a superconducting atom chip operated at liquid Helium temperatures. Up to $8.2\\cdot 10^5$ atoms are held in a Ioffe-Pritchard trap at a distance of 440 $\\mu$m from the chip surface, with a temperature of 40 $\\mu$K. The trap lifetime reaches 115 s at low atomic densities. These results open the way to the exploration of atom--surface interactions and coherent atomic transport in a superconducting environment, whose properties are radically different from normal metals at room temperature.

  8. On Testing Entropic Inequalities for Superconducting Qudit

    E-Print Network [OSTI]

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

    2015-04-30T23:59:59.000Z

    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.

  9. Criterion of stability of the superconducting state

    E-Print Network [OSTI]

    Iogann Tolbatov

    2009-10-23T23:59:59.000Z

    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.

  10. Apparatus for characterizing conductivity of superconducting materials

    DOE Patents [OSTI]

    Doss, James D. (Los Alamos, NM)

    1993-01-01T23:59:59.000Z

    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.

  11. Apparatus for characterizing conductivity of superconducting materials

    DOE Patents [OSTI]

    Doss, J.D.

    1993-12-07T23:59:59.000Z

    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.

  12. Induced Magnetism in Color-Superconducting Media

    E-Print Network [OSTI]

    Efrain J. Ferrer

    2010-01-22T23:59:59.000Z

    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.

  13. SQCD, Superconducting Gaps and Cyclic RG Flows

    E-Print Network [OSTI]

    Alexander Gorsky

    2012-02-20T23:59:59.000Z

    We consider the relation between the \\Omega -deformed N=2 SQCD with the single deformation parameter and integrable models of the BCS-like superconductivity. It is argued that the vortex string worldsheet theory is related to the Russian Doll(RD) model of the truncated BCS superconductivity. We argue that the \\Omega -deformed gauge theory manifests the interesting cyclic RG behavior with the period of the RG cycle proportional to \\epsilon^{-1}. The deformed gauge theory can develop several non-perturbative scales. We conjecture on the monopole bound state interpretation of the Efimov tower.

  14. Superconducting DC and RF Properties of Ingot Niobium

    SciTech Connect (OSTI)

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

    2011-07-01T23:59:59.000Z

    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.

  15. HOM Coupler Optimisation for the Superconducting RF Cavities in ESS

    E-Print Network [OSTI]

    Ainsworth, R; Calaga, R

    2012-01-01T23:59:59.000Z

    The European Spallation Source (ESS) will be the world’s most powerful next generation neutron source. It consists of a linear accelerator, target, and instruments for neutron experiments. The linac is designed to accelerate protons to a ?nal energy of 2.5 GeV, with an average design beam power of 5 MW, for collision with a target used to produce a high neutron ?ux. A section of the linac will contain Superconducting RF (SCRF) cavities designed at 704 MHz. Beam induced HOMs in these cavities may drive the beam unstable and increase the cryogenic load, therefore HOM couplers are installed to provide suf?cient damping. Previous studies have shown that these couplers are susceptible to multipacting, a resonant process which can absorb RF power and lead to heating effects. This paper will show how a coupler suffering from multipacting has been redesigned to limit this effect. Optimisation of the RF damping is also discussed.

  16. 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

    2015-01-01T23:59:59.000Z

    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...

  17. Tests of prototype SSC (Superconducting Super Collider) magnets

    SciTech Connect (OSTI)

    Strait, J.; Brown, B.C.; Hanft, R.; Koepke, K.; Kuchnir, M.; Lundy, R.; Mantsch, P.; Mazur, P.O.; McInturff, A.; Orr, J.R.

    1987-09-21T23:59:59.000Z

    Results are presented from tests of the third full scale development dipole magnet for the Superconducting Super Collider and from a retest of a 4.5 m model magnet of the same design mounted in an SSC cryostat. The 4.5 m magnet shows consistent quench performance between its original tests in boiling liquid helium in a vertical dewar and the current tests in forced flow helium in a horizontal cryostat. Little or no retraining is observed over several thermal cycles. The full length magnet requires 12 quenches to train to its short sample limit of 6800 A and displays a reasonably stable quench plateau following training. This represents a great improvement over the performance of the first two full length magnets. Data are presented on quench behavior as a function of current and temperature and on azimuthal and longitudinal loading of the coil by the support structure. 14 refs., 7 figs.

  18. A prototype high-temperature superconducting coil for the 32 T all-superconducting magnet was constructed with YBCO tape and

    E-Print Network [OSTI]

    Weston, Ken

    A prototype high-temperature superconducting coil for the 32 T all- superconducting magnet T All-Superconducting Magnet Hubertus W. Weijers, W.D. Markiewicz, H. Bai, S.T. Hannahs National High

  19. Biochemical transformation of coals

    DOE Patents [OSTI]

    Lin, M.S.; Premuzic, E.T.

    1999-03-23T23:59:59.000Z

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed. 7 figs.

  20. Exploring Functional Mellin Transforms

    E-Print Network [OSTI]

    J. LaChapelle

    2015-01-08T23:59:59.000Z

    We define functional Mellin transforms within a scheme for functional integration proposed in [1]. Functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored.

  1. Deployment & Market Transformation (Brochure)

    SciTech Connect (OSTI)

    Not Available

    2012-04-01T23:59:59.000Z

    NREL's deployment and market transformation (D and MT) activities encompass the laboratory's full range of technologies, which span the energy efficiency and renewable energy spectrum. NREL staff educates partners on how they can advance sustainable energy applications and also provides clients with best practices for reducing barriers to innovation and market transformation.

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

    E-Print Network [OSTI]

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

    2015-01-08T23:59:59.000Z

    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.

  3. Logarithmic transformation of response Logarithmic transformation of response

    E-Print Network [OSTI]

    Komarek, Arnost

    Logarithmic transformation of response Logarithmic transformation of response Often, support S of Y is S = (0, ). Logarithm is then one of transformations to consider when trying to obtain a correct (wrong. Model Building 1. Transformation of response #12;Logarithmic transformation of response When does

  4. Program Transformation Mechanics A Classification of Mechanisms for Program Transformation

    E-Print Network [OSTI]

    Utrecht, Universiteit

    Program Transformation Mechanics A Classification of Mechanisms for Program Transformation with a Survey of Existing Transformation Systems Jonne van Wijngaarden Eelco Visser UU-CS-2003-048 Institute Transformation Mechanics A Classification of Mechanisms for Program Transformation with a Survey of Existing

  5. IMAGINED TRANSFORMATIONS 1 Running head: IMAGINED TRANSFORMATION OF BODIES

    E-Print Network [OSTI]

    Zacks, Jeffrey M.

    IMAGINED TRANSFORMATIONS 1 Running head: IMAGINED TRANSFORMATION OF BODIES Imagined Transformations TRANSFORMATIONS 2 Abstract A number of spatial reasoning problems can be solved by performing an imagined transformation of one's egocentric perspective. A series of experiments were carried out to characterize

  6. The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume

    E-Print Network [OSTI]

    Green, M.A.

    2008-01-01T23:59:59.000Z

    the Cost of Large Superconducting Thin Solenoid Magnets,"The Economics of Large Superconducting Toroidal Magnets forEnergy (MJ) Fig. 2. Superconducting magnet costs (M$) versus

  7. A discrete fractional random transform

    E-Print Network [OSTI]

    Zhengjun Liu; Haifa Zhao; Shutian Liu

    2006-05-20T23:59:59.000Z

    We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

  8. Cooling of Color Superconducting Compact Stars

    E-Print Network [OSTI]

    David Blaschke

    2006-03-26T23:59:59.000Z

    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.

  9. Positive and inverse isotope effect on superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-04T23:59:59.000Z

    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.

  10. Superconducting Technology Program: Sandia 1993 annual report

    SciTech Connect (OSTI)

    Roth, E.P. [Sandia National Labs., Albuquerque, NM (United States). Superconductivity Materials and Optical Properties Dept.

    1994-05-01T23:59:59.000Z

    Sandia`s STP program is a four-part high-temperature superconductor (HTS) research and development program consisting of efforts in powder synthesis and process development, thallium-based HTS film development, wire and tape fabrication, and HTS motor design. The objective of this work is to develop high-temperature superconducting conductors (wire and tape) capable of meeting requirements for high-power electrical devices of interest to industry. The four research efforts currently underway are: (1) process research on the material synthesis of high-temperature superconductors; (2) investigation of the synthesis and processing of thallium-based high-temperature superconducting thick films; (3) process development and characterization of high-temperature superconducting wire and tape, and (4) cryogenic design of a high-temperature superconducting motor. This report outlines the research that has been performed during FY93 in each of these four areas. A brief background of each project is included to provide historical context and perspective. Major areas of research are described, although no attempt has been made to exhaustively include all work performed in each of these areas.

  11. Superconducting Technology Program Sandia 1994 Annual Report

    SciTech Connect (OSTI)

    Roth, E.P.

    1995-10-01T23:59:59.000Z

    Sandia`s STP program is a four-part high-temperature superconductor (HTS) research and development program consisting of efforts in powder synthesis and process development, thallium-based HTS film development, wire and tape fabrication, and HTS motor design. The objective of this work is to develop high-temperature superconducting conductors (wire and tape) capable of meeting requirements for high-power electrical devices of interest to industry. The four research efforts currently underway are: (1) Process research on the material synthesis of high-temperature superconductors, (2) Investigation of the synthesis and processing of thallium-based high-temperature superconducting thick films, (3) Process development and characterization of high-temperature superconducting wire and tape, and (4) Cryogenic design of a high-temperature superconducting motor. This report outlines the research that has been performed during FY94 in each of these four areas. Major areas of research are described, although no attempt has been made to exhaustively include all work performed in each of these areas.

  12. Di-Antiquarks condensation in Color Superconductivity

    E-Print Network [OSTI]

    Fabio L. Braghin

    2006-11-30T23:59:59.000Z

    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.

  13. Experimental Investigations on Superconducting Niobium Cavities

    E-Print Network [OSTI]

    Experimental Investigations on Superconducting Niobium Cavities at Highest Radiofrequency Fields niobium cavities, electrolytic polishing was applied to 1.3 GHz single cell and nine-cell cavities . . . . . . . . . . . . . . . . . . . . 14 1.4.1 Cavity fabrication . . . . . . . . . . . . . . . . . . . . . 16 1.4.1.1 Niobium properties

  14. Geometrical Dynamics in a Transitioning Superconducting Sphere

    E-Print Network [OSTI]

    James R. Claycomb; Rambis K. Chu

    2006-02-22T23:59:59.000Z

    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.

  15. Michigan State University National Superconducting Cyclotron Laboratory

    E-Print Network [OSTI]

    Yannouleas, Constantine

    Michigan State University National Superconducting Cyclotron Laboratory East Lansing, Michigan USA (University of Manchester, UK) Joseph CARLSON (Los Alamos National laboratory, USA) Mark DYKMAN (Michigan Lectureship Endowment at Michigan State University Please register by contacting lesliel@nscl.msu.edu The main

  16. Mesoscopic Shelving Readout of Superconducting Qubits in

    E-Print Network [OSTI]

    Gross, Rudolf

    Mesoscopic Shelving Readout of Superconducting Qubits in Circuit Quantum Electrodynamics Diploma Shelving Readout. The proposed protocol associates one qubit state with the generation of a mesoscopic which enables a high-fidelity measurement in the spirit of the successful electron shelving readout

  17. Beam heat load in superconducting wigglers

    E-Print Network [OSTI]

    Casalbuoni, S

    2013-01-01T23:59:59.000Z

    The beam heat load is a fundamental input parameter for the design of superconducting wigglers since it is needed to specify the cooling power. In this presentation I will review the possible beam heat load sources and the measurements of beam heat load performed and planned onto the cold vacuum chambers installed at different synchrotron light sources.

  18. Lorentz transformation by mimicking the Lorentz transformation

    E-Print Network [OSTI]

    Bernhard Rothenstein; Stefan Popescu

    2007-09-24T23:59:59.000Z

    We show that starting with the fact that special relativity theory is concerned with a distortion of the observed length of a moving rod, without mentioning if it is a "contraction" or "dilation", we can derive the Lorentz transformations for the spacetime coordinates of the same event. This derivation is based on expressing the length of the moving rod as a sum of components with all the lengths involved in this summation being measured by the observers of the same inertial reference frame.

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

    E-Print Network [OSTI]

    Yaniv Almog; Bernard Helffer; Xing-Bin Pan

    2015-05-23T23:59:59.000Z

    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.

  20. Applying Improved Efficiency Transformers

    E-Print Network [OSTI]

    Haggerty, N. K.; Malone, T. P.

    primary and secondary windings, and vary significantly with transformer loading. Load or conductor losses vary with the square of the per unit load. Average full load losses of a 1500 kVA transformer can range from 11 to 21 kW. Manufacturers can... to meet the requirements of a particular transformer specification. These designs will have varying amounts of core steel and copper or aluminum conductors with differing no-load and load losses. The lowest cost design that meets all the applicable...

  1. Transforming California's Freight Transport System

    E-Print Network [OSTI]

    California at Davis, University of

    Transforming California's Freight Transport System Policy Forum on the Role of Freight Transport Standard #12;2050 Vision- Key Conceptual Outcomes Technology Transformation Early Action Cleaner Combustion Multiple Strategies Federal Action Efficiency Gains Energy Transformation 9 #12;Further reduce localized

  2. The Quantum Mellin transform

    E-Print Network [OSTI]

    J. Twamley; G. J. Milburn

    2007-02-12T23:59:59.000Z

    We uncover a new type of unitary operation for quantum mechanics on the half-line which yields a transformation to ``Hyperbolic phase space''. We show that this new unitary change of basis from the position x on the half line to the Hyperbolic momentum $p_\\eta$, transforms the wavefunction via a Mellin transform on to the critial line $s=1/2-ip_\\eta$. We utilise this new transform to find quantum wavefunctions whose Hyperbolic momentum representation approximate a class of higher transcendental functions, and in particular, approximate the Riemann Zeta function. We finally give possible physical realisations to perform an indirect measurement of the Hyperbolic momentum of a quantum system on the half-line.

  3. Transformation inverse design

    E-Print Network [OSTI]

    Liu, David

    We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is ...

  4. Series Transmission Line Transformer

    DOE Patents [OSTI]

    Buckles, Robert A. (Livermore, CA); Booth, Rex (Livermore, CA); Yen, Boris T. (El Cerrito, CA)

    2004-06-29T23:59:59.000Z

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  5. Functional Mellin Transforms

    E-Print Network [OSTI]

    J. LaChapelle

    2015-01-07T23:59:59.000Z

    Functional integrals are defined in terms of locally compact topological groups and their associated Banach-valued Haar integrals. This approach generalizes the functional integral scheme of Cartier and DeWitt-Morette. The definition allows a construction of functional Mellin transforms. In turn, the functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored.

  6. Niobium thin film deposition studies on copper surfaces for superconducting radio frequency cavity applications

    SciTech Connect (OSTI)

    W. M. Roach, D. B. Beringer, J. R. Skuza, W. A. Oliver, C. Clavero, C. E. Reece, R. A. Lukaszew

    2012-06-01T23:59:59.000Z

    Thin film coatings have the potential to increase both the thermal efficiency and accelerating gradient in superconducting radio frequency accelerator cavities. However, before this potential can be realized, systematic studies on structure-property correlations in these thin films need to be carried out since the reduced geometry, combined with specific growth parameters, can modify the physical properties of the materials when compared to their bulk form. Here, we present our systematic studies of Nb thin films deposited onto Cu surfaces to clarify possible reasons for the limited success that this process exhibited in previous attempts. We compare these films with Nb grown on other surfaces. In particular, we study the crystal structure and surface morphology and their effect on superconducting properties, such as critical temperature and lower critical field. We found that higher deposition temperature leads to a sharper critical temperature transition, but also to increased roughness indicating that there are competing mechanisms that must be considered for further optimization.

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    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.

  8. Measurements of AC Losses and Current Distribution in Superconducting Cables

    SciTech Connect (OSTI)

    Nguyen, Doan A [Los Alamos National Laboratory (LANL); Ashworth, Stephen P [Los Alamos National Laboratory (LANL); Duckworth, Robert C [ORNL; Carter, Bill [AMSC; Fleshler, Steven [AMER Superconductor Corp, Devens, MA 01434

    2011-01-01T23:59:59.000Z

    This paper presents our new experimental facility and techniques to measure ac loss and current distribution between the layers for High Temperature Superconducting (HTS) cables. The facility is powered with a 45 kVA three-phase power supply which can provide three-phase currents up to 5 kA per phase via high current transformers. The system is suitable for measurements at any frequency between 20 and 500 Hz to better understand the ac loss mechanisms in HTS cables. In this paper, we will report techniques and results for ac loss measurements carried out on several HTS cables with and without an HTS shielding layer. For cables without a shielding layer, care must be taken to control the effect of the magnetic fields from return currents on loss measurements. The waveform of the axial magnetic field was also measured by a small pick-up coil placed inside a two-layer cable. The temporal current distribution between the layers can be calculated from the waveform of the axial field.

  9. Creation of Electron Spinless Pairs in the Superconductivity

    E-Print Network [OSTI]

    V. N. Minasyan

    2009-03-28T23:59:59.000Z

    First, it is demonstrated that the Froolich Hamiltonian of system in the superconductivity, proposed by the model of a phonon gas and an electron gas mixture, contains a subtle error. In this respect, we present a correct form of the Froolich Hamiltonian of system where the term of the interaction between the phonon modes and the density modes of the electron modes is described by the term of scattering, introduced by the Froolich in a phonon gas electron gas mixture. The later is removed by a canonical transformation of the Froolich Hamiltonian by an appearance of the attractive interaction mediated via the electron modes, which leads to a bound state on a spinless electron pairs. In this letter, we show that the Cooper approximation as the constancy of the density states within around of the Fermi level has a flaw because the effective attractive forces cannot create the Cooper pairs into energetic gap at the Fermi level. In this letter, we find a condition for density metal which determines metal as superconductor.

  10. 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)

    2002-01-01T23:59:59.000Z

    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.

  11. Process Limits on Euclid

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

    Process Limits Process Limits Limit Hard Soft core file size (blocks) 0 unlimited data seg size (kbytes) unlimited unlimited scheduling priority 0 0 file size (blocks) unlimited...

  12. Optical transformation from chirplet to fractional Fourier transformation kernel

    E-Print Network [OSTI]

    Hong-yi Fan; Li-yun Hu

    2009-02-11T23:59:59.000Z

    We find a new integration transformation which can convert a chirplet function to fractional Fourier transformation kernel, this new transformation is invertible and obeys Parseval theorem. Under this transformation a new relationship between a phase space function and its Weyl-Wigner quantum correspondence operator is revealed.

  13. From transformation traces to transformation rules: Assisting Model Driven Engineering

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    From transformation traces to transformation rules: Assisting Model Driven Engineering approach. In this paper we are interested in semi-automatically gen- erating labelled graph (model) transformations conform to a particu- lar syntax (meta-model). Those transformations are basic operations in model driven

  14. Laplace Transforms An integral transform is an operator

    E-Print Network [OSTI]

    Ikenaga, Bruce

    9­28­1998 Laplace Transforms An integral transform is an operator F (s) = Z b a K(s; t)f(t) dt: The input to the transform is the function f(t); the output is the function F (s). (By convention, small letters denote the inputs to a transform, and the corresponding capital letters denote the corresponding

  15. APPENDIX F. TRANSFORMS, COMPLEX ANALYSIS 1 Transforms, Complex

    E-Print Network [OSTI]

    Callen, James D.

    APPENDIX F. TRANSFORMS, COMPLEX ANALYSIS 1 Appendix F Transforms, Complex Analysis This appendix discusses Fourier and Laplace transforms as they are used in plasma physics and this book. Also, key properties of complex variable theory that are needed for understanding and inverting these transforms

  16. Planar LTCC transformers for high voltage flyback converters.

    SciTech Connect (OSTI)

    Schofield, Daryl (NASCENT Technology Inc. , Watertown, SD); Schare, Joshua M.; Glass, Sarah Jill; Roesler, Alexander William; Ewsuk, Kevin Gregory; Slama, George (NASCENT Technology Inc. , Watertown, SD); Abel, Dave (NASCENT Technology Inc. , Watertown, SD)

    2007-06-01T23:59:59.000Z

    This paper discusses the design and use of low-temperature (850 C to 950 C) co-fired ceramic (LTCC) planar magnetic flyback transformers for applications that require conversion of a low voltage to high voltage (> 100V) with significant volumetric constraints. Measured performance and modeling results for multiple designs showed that the LTCC flyback transformer design and construction imposes serious limitations on the achievable coupling and significantly impacts the transformer performance and output voltage. This paper discusses the impact of various design factors that can provide improved performance by increasing transformer coupling and output voltage. The experiments performed on prototype units demonstrated LTCC transformer designs capable of greater than 2 kV output. Finally, the work investigated the effect of the LTCC microstructure on transformer insulation. Although this paper focuses on generating voltages in the kV range, the experimental characterization and discussion presented in this work applies to designs requiring lower voltage.

  17. Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini and Miklos Porkolab

    E-Print Network [OSTI]

    Superconducting Magnets Research for a Viable US Fusion Program Joseph V rely on superconducting magnets for efficient and reliable production of these magnetic fields. Superconducting magnet technology is a powerful knob

  18. Nb3Sn superconducting magnets for electron cyclotron resonance ion sources

    E-Print Network [OSTI]

    Ferracin, P.

    2011-01-01T23:59:59.000Z

    the design of a N b S n superconducting magnet system for aNbjSn superconducting magnets for electron cyclotron5 C H 1 1 2 3 1 . Nb Sn superconducting magnets for electron

  19. Excitation of Superconducting Qubits from Hot Nonequilibrium Quasiparticles J. Wenner,1

    E-Print Network [OSTI]

    Martinis, John M.

    Excitation of Superconducting Qubits from Hot Nonequilibrium Quasiparticles J. Wenner,1 Yi Yin,1 manuscript received 4 March 2013; published 9 April 2013) Superconducting qubits probe environmental defects quasiparticles, with energies above the superconducting gap, affect qubits differently from quasiparticles

  20. Color superconductivity with determinant interaction in strange quark matter

    E-Print Network [OSTI]

    Amruta Mishra; Hiranmaya Mishra

    2006-08-28T23:59:59.000Z

    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.

  1. Uranium transformations in static microcosms.

    SciTech Connect (OSTI)

    Kelly, S. D.; Wu, W.; Yang, F.; Criddle, C.; Marsh, T. L.; O'Loughlin, E. J.; Ravel, B.; Watson, D.; Jardine, P. M.; Kemner, K. M.; Stanford Univ.; Michigan State Univ.; ORNL; BNL; EXAFS Analysis

    2010-01-01T23:59:59.000Z

    Elucidation of complex biogeochemical processes and their effects on speciation of U in the subsurface is critical for developing remediation strategies with an understanding of stability. We have developed static microcosms that are similar to bioreduction process studies in situ under laminar flow conditions or in sediment pores. Uranium L{sub 3}-edge X-ray absorption near-edge spectroscopy analysis with depth in the microcosms indicated that transformation of U{sup VI} to U{sup IV} occurred by at least two distinct processes. Extended X-ray absorption fine structure (EXAFS) analysis indicated that initial U{sup VI} species associated with C- and P-containing ligands were transformed to U{sup IV} in the form of uraninite and U associated with Fe-bound ligands. Microbial community analysis identified putative Fe{sup III} and sulfate reducers at two different depths in the microcosms. The slow reduction of U{sup VI} to U{sup IV} may contribute the stability of U{sup IV} within microcosms at 11 months after a decrease in bioreducing conditions due to limited electron donors.

  2. Design and testing of a 13. 75-MW converter for a superconducting magnetic-energy-storage system

    SciTech Connect (OSTI)

    Boenig, H.J.; Turner, R.D.; Neft, C.L.; Sueker, K.H.

    1981-01-01T23:59:59.000Z

    A 30 MJ superconducting magnetic energy storage system will be installed in 1982 in Tacoma, WA, to act as a transmission line stabilizer. Two 6 MVA transformers and a 5.5 kA, + 2.5 kV converter will connect the superconducting coil to the 13.8 kV bus and regulate the power flow between the coil and the three phase system. The design philosophy for the converter including its control and protection system is given in the paper. The converter has been tested with 10% overvoltage at no load, with 10% overcurrent at zero output voltage and with a watercooled resistive load of about 1 MW. These test results show that the converter will meet the expected full load operating conditions.

  3. A New Approach for Line Recognition in Large-size Images Using Hough Transform

    E-Print Network [OSTI]

    Lyu, Michael R.

    is very time- efficient for large-size images. 1. Introduction Hough Transform (HT) is a powerful toolA New Approach for Line Recognition in Large-size Images Using Hough Transform Jiqiang Song, Min Transform (HT) has been limited to small-size images for a long time. For large-size images, the peak

  4. PHYS 301 --Introduction to Mathematical Physics Chapter 7 Fourier Series and Transforms (Section 11-12)

    E-Print Network [OSTI]

    Ng, Chung-Sang

    PHYS 301 -- Introduction to Mathematical Physics Chapter 7 Fourier Series and Transforms (Section (Bessel's inequality). (iii) Fourier transforms can be thought of Fourier series in a limit when in most physical situations are non-periodic. (iv) Parseval's Theorem can be applied to Fourier transforms

  5. Processing of superconductive materials and high frequency

    SciTech Connect (OSTI)

    Smith, J.L.

    1987-01-01T23:59:59.000Z

    We do not know yet if superconductivity will become useful without refrigeration. Now, the superconductors are so different from copper that it is difficult to imagine replacing copper with such a brittle material. Superconductors conduct dc with no loss, ac with small losses, and microwaves in co-axial lines with almost no loss and with no dispersion from dc to the highest frequencies. They will probably allow us to close the gap between radio frequency and infrared optical transmission. Clearly your industry should know some things about where superconductivity may lead us and must consider whether the greater risk is to develop them or to let others try it. There are no easy answers yet.

  6. Superconducting cuprate heterostructures for hot electron bolometers

    SciTech Connect (OSTI)

    Wen, B.; Yakobov, R.; Vitkalov, S. A. [Department of Physics, City College of New York, New York 10031 (United States)] [Department of Physics, City College of New York, New York 10031 (United States); Sergeev, A. [SUNY Research Foundation, SUNY at Buffalo, Buffalo, New York 14226 (United States)] [SUNY Research Foundation, SUNY at Buffalo, Buffalo, New York 14226 (United States)

    2013-11-25T23:59:59.000Z

    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.

  7. Magnetic Field Evolution in Superconducting Neutron Stars

    E-Print Network [OSTI]

    Graber, Vanessa; Glampedakis, Kostas; Lander, Samuel K

    2015-01-01T23:59:59.000Z

    The presence of superconducting and superfluid components in the core of mature neutron stars calls for the rethinking of a number of key magnetohydrodynamical notions like resistivity, the induction equation, magnetic energy and flux-freezing. Using a multi-fluid magnetohydrodynamics formalism, we investigate how the magnetic field evolution is modified when neutron star matter is composed of superfluid neutrons, type-II superconducting protons and relativistic electrons. As an application of this framework, we derive an induction equation where the resistive coupling originates from the mutual friction between the electrons and the vortex/fluxtube arrays of the neutron and proton condensates. The resulting induction equation allows the identification of two timescales that are significantly different from those of standard magnetohydrodynamics. The astrophysical implications of these results are briefly discussed.

  8. Superconductivity and the BCS-Bogoliubov Theory

    E-Print Network [OSTI]

    Shuji Watanabe

    2010-06-07T23:59:59.000Z

    First, we reformulate the BCS-Bogoliubov theory of superconductivity from the viewpoint of linear algebra. We define the BCS Hamiltonian on $\\mathbb{C}^{2^{2M}}$, where $M$ is a positive integer. We discuss selfadjointness and symmetry of the BCS Hamiltonian as well as spontaneous symmetry breaking. Beginning with the gap equation, we give the well-known expression for the BCS state and find the existence of an energy gap. We also show that the BCS state has a lower energy than the normal state. Second, we introduce a new superconducting state explicitly and show from the viewpoint of linear algebra that this new state has a lower energy than the BCS state. Third, beginning with our new gap equation, we show from the viewpoint of linear algebra that we arrive at the results similar to those in the BCS-Bogoliubov theory.

  9. Optomechanical-like coupling between superconducting resonators

    E-Print Network [OSTI]

    J. R. Johansson; G. Johansson; Franco Nori

    2014-03-18T23:59:59.000Z

    We propose and analyze a circuit that implements a nonlinear coupling between two superconducting microwave resonators. The resonators are coupled through a superconducting quantum interference device (SQUID) that terminates one of the resonators. This produces a nonlinear interaction on the standard optomechanical form, where the quadrature of one resonator couples to the photon number of the other resonator. The circuit therefore allows for all-electrical realizations of analogs to optomechanical systems, with coupling that can be both strong and tunable. We estimate the coupling strengths that should be attainable with the proposed device, and we find that the device is a promising candidate for realizing the single-photon strong-coupling regime. As a potential application, we discuss implementations of networks of nonlinearly-coupled microwave resonators, which could be used in microwave-photon based quantum simulation.

  10. Maximum screening fields of superconducting multilayer structures

    E-Print Network [OSTI]

    Gurevich, Alex

    2015-01-01T23:59:59.000Z

    It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields $H_s$ of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness $\\sim 0.1\\; \\mu$m at the Nb surface could increase $H_s\\simeq 240$ mT of a clean Nb up to $H_s\\simeq 290$ mT. Optimized multilayers of Nb$_3$Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.

  11. Heavy electron superconductivity: From 1K to 90K to

    SciTech Connect (OSTI)

    Pethick, C.J.; Pines, D.

    1987-01-01T23:59:59.000Z

    This paper reviews the experimental results and physical arguments which led us to conclude that in heavy electron systems the physical mechanism responsible for superconductivity is an attractive interaction between the heavy electrons which results from the virtual exchange of antiferromagnetic f-electron moment fluctuations. In these systems, then, the superconductivity is of purely electronic origin; the phonon-induced interaction between electrons which leads to superconductivity in ordinary metals plays little or no role.

  12. High temperature superconductivity in metallic region near Mott transition

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-11T23:59:59.000Z

    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.

  13. Ted Geballe: A Lifetime of Contributions To Superconductivity

    E-Print Network [OSTI]

    Stewart, G R

    2015-01-01T23:59:59.000Z

    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.

  14. Substrates suitable for deposition of superconducting thin films

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

    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.

  15. Method for manufacturing a rotor having superconducting coils

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

    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.

  16. Generalization of Conformal Transformations

    E-Print Network [OSTI]

    G. I. Garas'ko

    2005-09-19T23:59:59.000Z

    Conformal transformations of a Euclidean (complex) plane have some kind of completeness (sufficiency) for the solution of many mathematical and physical-mathematical problems formulated on this plane. There is no such completeness in the case of Euclidean, pseudo-Euclidean and polynumber spaces of dimension greater than two. In the present paper we show that using the concepts of analogical geometries allows us to generalize conformal transformations not only to the case of Euclidean or pseudo-Euclidean spaces, but also to the case of Finsler spaces, analogous to the spaces of affine connectedness. Examples of such transformations in the case of complex and hypercomplex numbers H_4 are presented. In the general case such transformations form a group of transitions, the elements of which can be viewed as transitions between projective Euclidean geometries of a distinguished class fixed by the choice of metric geometry admitting affine coordinates. The correlation between functions realizing generalized conformal transformations and generalized analytical functions can appear to be productive for the solution of fundamental problems in theoretical and mathematical physics.

  17. 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

    2006-09-14T23:59:59.000Z

    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.

  18. On a Model of Superconductivity and Biology

    E-Print Network [OSTI]

    Monica De Angelis

    2012-03-02T23:59:59.000Z

    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.

  19. Magnetism and superconductivity in quark matter

    E-Print Network [OSTI]

    T. Tatsumi; E. Nakano; K. Nawa

    2005-06-01T23:59:59.000Z

    Magnetic properties of quark matter and its relation to the microscopic origin of the magnetic field observed in compact stars are studied. Spontaneous spin polarization appears in high-density region due to the Fock exchange term, which may provide a scenario for the behaviors of magnetars. On the other hand, quark matter becomes unstable to form spin density wave in the moderate density region, where restoration of chiral symmetry plays an important role. Coexistence of magnetism and color superconductivity is also discussed.

  20. Dual superconducting properties of the QCD vacuum

    E-Print Network [OSTI]

    A. D'Alessandro; M. D'Elia

    2005-10-27T23:59:59.000Z

    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.

  1. Rotor assembly including superconducting magnetic coil

    DOE Patents [OSTI]

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

    2003-01-01T23:59:59.000Z

    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.

  2. Holographic Superconductivity with Gauss-Bonnet gravity

    E-Print Network [OSTI]

    Ruth Gregory

    2010-12-07T23:59:59.000Z

    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.

  3. Discrete Fourier Transform Javier Montoya

    E-Print Network [OSTI]

    Giger, Christine

    Discrete Fourier Transform Javier Montoya Photogrammetry and Remote Sensing ETH Zurich March 16, 2012 1 Introduction The Discrete form of the Fourier transform is known as Discrete Fourier Transform domain using the Inverse Discrete Fourier Transform (IDFT): f(x) = 1 N N-1 x=0 F(u)ej 2 N ux for u = 0, 1

  4. Los Alamos scientists see new mechanism for superconductivity

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

    In a November 20 Nature letter, research led by Tuson Park and Joe D. Thompson describes a new explanation for superconductivity in non-traditional materials-one...

  5. The Breakdown of Superconductivity Due to Strong Fields for the ...

    E-Print Network [OSTI]

    John Rogosich (Techsetters) 114 2000 Jul 12 13:05:01

    2002-04-22T23:59:59.000Z

    We study the behavior of a superconducting material subjected to a constant applied ... show the existence of a critical field h, for which, when h > h, the normal ...

  6. Magnetism and superconductivity observed to exist in harmony

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

    hundreds of degrees below zero, they will be one step closer to the "holy grail" of modern condensed matter physics: superconductivity at temperatures high enough to...

  7. 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)

    2009-12-15T23:59:59.000Z

    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.

  8. Type-I superconductivity and neutron star precession

    E-Print Network [OSTI]

    Armen Sedrakian

    2005-03-30T23:59:59.000Z

    Type-I proton superconducting cores of neutron stars break up in a magnetic field into alternating domains of superconducting and normal fluids. We examine two channels of superfluid-normal fluid friction where (i) rotational vortices are decoupled from the non-superconducting domains and the interaction is due to the strong force between protons and neutrons; (ii) the non-superconducting domains are dynamically coupled to the vortices and the vortex motion generates transverse electric fields within them, causing electronic current flow and Ohmic dissipation. The obtained dissipation coefficients are consistent with the Eulerian precession.

  9. 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

    2014-08-07T23:59:59.000Z

    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.

  10. ac superconducting power: Topics by E-print Network

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

    Z. Hong, Y. Yan, R. Pei, Y. Jiang and T. A. Coombs, Design... and test of a Superconduct- ing Magnetic Energy Storage (SMES) coil, IEEE transaction on applied...

  11. amorphous wc superconducting: Topics by E-print Network

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

    Summary: alloy of composition correspond- ing to the metallic components of the superconduct- ing oxides respectivement. Abstract. - Previous quenching experiments on 2212...

  12. atlas superconducting magnet: Topics by E-print Network

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

    the High Energy Storage Ring (HESR) Index Terms--Antiproton beams, fast-ramped superconduct- ing Ohta, Shigemi 237 Engineering Design and Manufacturing Challenges for a...

  13. Superconductivity, superfluidity and zero-point oscillations

    E-Print Network [OSTI]

    B. V. Vasiliev

    2013-06-29T23:59:59.000Z

    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.

  14. Rotatable superconducting cyclotron adapted for medical use

    DOE Patents [OSTI]

    Blosser, Henry G. (East Lansing, MI); Johnson, David A. (Williamston, MI); Riedel, Jack (East Lansing, MI); Burleigh, Richard J. (Berkeley, CA)

    1985-01-01T23:59:59.000Z

    A superconducting cyclotron (10) rotatable on a support structure (11) in an arc of about 180.degree. around a pivot axis (A--A) and particularly adapted for medical use is described. The rotatable support structure (13, 15) is balanced by being counterweighted (14) so as to allow rotation of the cyclotron and a beam (12), such as a subparticle (neutron) or atomic particle beam, from the cyclotron in the arc around a patient. Flexible hose (25) is moveably attached to the support structure for providing a liquified gas which is supercooled to near 0.degree. K. to an inlet means (122) to a chamber (105) around superconducting coils (101, 102). The liquid (34) level in the cyclotron is maintained approximately half full so that rotation of the support structure and cyclotron through the 180.degree. can be accomplished without spilling the liquid from the cyclotron. With the coils vertically oriented, each turn of the winding is approximately half immersed in liquid (34) and half exposed to cold gas and adequate cooling to maintain superconducting temperatures in the section of coil above the liquid level is provided by the combination of cold gas/vapor and by the conductive flow of heat along each turn of the winding from the half above the liquid to the half below.

  15. Magnetar superconductivity versus magnetism: neutrino cooling processes

    E-Print Network [OSTI]

    Sinha, Monika

    2015-01-01T23:59:59.000Z

    We describe the microphysics, phenomenology, and astrophysical implication of a $B$-field induced unpairing effect that may occur in magnetars, if the local $B$-field in the core of a magnetar exceeds a critical value $H_{c2}$. Using the Ginzburg-Landau (GL) theory of superconductivity, we derive the $H_{c2}$ field for proton condensate taking into the correction ($\\le 30\\%$) which arises from its coupling to the background neutron condensate. The density dependence of pairing of proton condensate implies that $H_{c2}$ is maximal at the crust-core interface and decreases towards the center of the star. As a consequence, magnetar cores with homogenous constant fields will be partially superconducting for "medium-field" magnetars ($10^{15}\\le B\\le 5 \\times 10^{16}$ G) whereas "strong-field" magnetars ($B>5\\times 10^{16}$ G) will be void of superconductivity. The emissivity of a magnetar's core changes in twofold manner: (i)~the $B$-field assisted direct Urca process is enhanced by orders of magnitude, because o...

  16. Color superconducting quark matter in compact stars

    E-Print Network [OSTI]

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

    2007-12-02T23:59:59.000Z

    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.

  17. Diameter-bandwidth product limitation of isolated-object cloaking

    E-Print Network [OSTI]

    Joannopoulos, John D.

    We show that cloaking of isolated objects using transformation-based cloaks is subject to a diameter-bandwidth product limitation: as the size of the object increases, the bandwidth of good (small-cross-section) cloaking ...

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

    E-Print Network [OSTI]

    Eberhard, P.H.

    2010-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Kresin, Vladimir

    2010-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Smith, Kevin Daniel

    2008-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Sayles, Todd Allen

    2008-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

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

  3. ag-clad bi-based superconducting: Topics by E-print Network

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

    are described. Hbner, K 2001-01-01 77 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

  4. Coordinate transformations in quaternion spaces

    E-Print Network [OSTI]

    Zihua Weng

    2009-05-15T23:59:59.000Z

    The quaternion spaces can be used to describe the property of electromagnetic field and gravitational field. In the quaternion space, some coordinate transformations can be deduced from the feature of quaternions, including Lorentz transformation and Galilean transformation etc., when the coordinate system is transformed into others. And some coordinate transformations with variable speed of light can be obtained in the electromagnetic field and gravitational field.

  5. Tuning the Superconducting Properties of Magnesium Diboride

    SciTech Connect (OSTI)

    Rudeger Heinrich Theoderich Wilke

    2005-12-17T23:59:59.000Z

    This work is presented in the following order: A review of the relevant physics and discussion of theoretical predictions for a two gap superconducting compound is given in chapter 2. Chapter 3 provides a review of the basic properties of MgB{sub 2}. Details of sample synthesis and characterization are given in chapter 4. Chapter 5 presents normal state and superconducting properties of Mg(B{sub 1-x}C{sub x}){sub 2} wires. Attempts to increase critical current densities in filaments via titanium additions are discussed in chapter 6. In chapters 7 and 8 alternative methods for synthesizing doped MgB{sub 2} powders are explored. In chapter 7 we synthesize Mg(B{sub 1-x}C{sub x}){sub 2} up to x=0.069 using a mixture of Mg, B, and the binary compound B{sub 4}C. Chapter 8 explores an alternative method, plasma spray synthesis, to produce nanometer sized doped boron powders for powder-in-tube applications. The effects of neutron irradiation on pure MgB{sub 2} wires is discussed in chapter 9. This is followed by a study of the effects of neutron irradiation on Mg(B{sub .962}C{sub .038}){sub 2} wires, presented in chapter 10. I will summarize the results of all of these studies in chapter 11 and discuss future directions for research in understanding the physics behind this novel material as well as its development for practical applications. In this thesis I have presented the results of investigations into the changes in the superconducting properties of MgB{sub 2} as a function of carbon doping and neutron irradiation. The goal has been to understand the physics underlying this unique two-gap superconductor as different types of perturbations are made to the system. Such knowledge not only contributes to our understanding of two-gap superconductivity, but could potentially lead to the development of superconducting MgB{sub 2} wires for the use in power applications near 20 K.

  6. Fourier Transform Infrared Spectroscopy

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    FTIR - 1 Fourier Transform Infrared Spectroscopy FTIR DETERMINATION OF MTBE IN GASOLINE AND ETHANOL FTIR DETERMINATION OF MTBE IN GASOLINE AND ETHANOL IN VODKA AND MOUTHWASH INTRODUCTION As a part has contained MTBE (methyl tert­butyl ether) as its primary oxygenate. However, there has been

  7. Transforming Education at Einstein

    E-Print Network [OSTI]

    Yates, Andrew

    Transforming Education at Einstein EinstEin Winter/spring 2012 The Magazine for Alumni and Friends of Albert Einstein College of Medicine of Yeshiva University #12;2 EinstEin : WintEr/spring 2012 Meet Our interactive Companion Magazine Give Einstein's "virtual" version a try! this interactive version

  8. Research Councils UK Transforming

    E-Print Network [OSTI]

    Berzins, M.

    Research Councils UK Transforming our energy future #12;Research funded by the Research Councils in 2002 to create a viable renewable energy research community to foster industrial engagement of research, expertise and the business capability to develop and exploit them commercially. Energy and its

  9. TO TRANSFORM BIOMEDICAL ENGINEERING

    E-Print Network [OSTI]

    IT'S TIME TO TRANSFORM BIOMEDICAL ENGINEERING EDUCATION #12;Charles H. & Bettye Barclay Professor Head, Department of Biomedical Engineering Texas A&M University We're dedicated to solving the world in biomedical engineering research and education ­ and we're well on our way. Our faculty continues to engineer

  10. Long-time limit of correlation functions

    E-Print Network [OSTI]

    Thomas Franosch

    2014-07-31T23:59:59.000Z

    Auto-correlation functions in an equilibrium stochastic process are well-characterized by Bochner's theorem as Fourier transforms of a finite symmetric Borel measure. The existence of a long-time limit of these correlation functions depends on the spectral properties of the measure. Here we provide conditions applicable to a wide-class of dynamical theories guaranteeing the existence of the long-time limit. We discuss the implications in the context of the mode-coupling theory of the glass transition where a non-trivial long-time limit signals an idealized glass state.

  11. MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY

    E-Print Network [OSTI]

    COURSE 7 MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY MATTHEW P.A. FISHER insulators and quantum magnetism 583 3.1 Spin models and quantum magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . 637 #12;MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY Matthew P.A. Fisher

  12. Superconductivity in gallium-substituted Ba8Si46 clathrates

    E-Print Network [OSTI]

    Li, Yang; Zhang, Ruihong; Liu, Yang; Chen, Ning; Luo, Z. P.; Ma, Xingqiao; Cao, Guohui; Feng, Z. S.; Hu, Chia-Ren; Ross, Joseph H., Jr.

    2007-01-01T23:59:59.000Z

    superconductor, with an onset at T-C approximate to 3.3 K. For x=10 and higher, no superconductivity was observed down to T=1.8 K. This represents a strong suppression of superconductivity with increasing Ga content, compared to Ba8Si46 with T-C approximate to 8...

  13. Superconductivity in gallium-substituted Ba8Si46 clathrates 

    E-Print Network [OSTI]

    Li, Yang; Zhang, Ruihong; Liu, Yang; Chen, Ning; Luo, Z. P.; Ma, Xingqiao; Cao, Guohui; Feng, Z. S.; Hu, Chia-Ren; Ross, Joseph H., Jr.

    2007-01-01T23:59:59.000Z

    superconductor, with an onset at T-C approximate to 3.3 K. For x=10 and higher, no superconductivity was observed down to T=1.8 K. This represents a strong suppression of superconductivity with increasing Ga content, compared to Ba8Si46 with T-C approximate to 8...

  14. A new boson-fermion model of superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2012-10-09T23:59:59.000Z

    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.

  15. Superconducting magnetic energy storage for asynchronous electrical systems

    DOE Patents [OSTI]

    Boenig, Heinrich J. (Los Alamos, NM)

    1986-01-01T23:59:59.000Z

    A superconducting magnetic energy storage coil connected in parallel between converters of two or more ac power systems provides load leveling and stability improvement to any or all of the ac systems. Control is provided to direct the charging and independently the discharging of the superconducting coil to at least a selected one of the ac power systems.

  16. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

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

    1996-09-10T23:59:59.000Z

    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.

  17. Surface Studies on Niobium for Superconductivity Radio Frequency (SRF) Accelerator

    E-Print Network [OSTI]

    Shaw, Leah B.

    Surface Studies on Niobium for Superconductivity Radio Frequency (SRF) Accelerator Hui Tian College Kelley, Professor of Applied Science Abstract Niobium rf superconductivity is a nanoscale, near employed treatment-BCP on polycrystalline niobium sheet over a range of realistic solution flow rates has

  18. ION BEAM MACHINING OF NIOBIUM WEAKLY SUPERCONDUCTING MICROBRIDGES

    E-Print Network [OSTI]

    Boyer, Edmond

    179 ION BEAM MACHINING OF NIOBIUM WEAKLY SUPERCONDUCTING MICROBRIDGES R. ADDE, P. CROZAT, S réduite représentant la structure à usiner. Les propriétés de microponts Josephson en niobium sont ensuite to be machin- ed. We describe and discuss the superconducting properties of niobium Josephson microbridges

  19. Superconducting transition temperature in heterogeneous ferromagnet-superconductor systems

    E-Print Network [OSTI]

    Pokrovsky, Valery L.; Wei, HD.

    2004-01-01T23:59:59.000Z

    We study the superconducting phase transition in two systems: ferromagnet-superconductor bilayer (FSB) and a thin superconducting film with a periodic array of magnetic dots (SFMD) upon it. We show that this transition is of the first order in FSB...

  20. A Simple Derivation of Josephson Formulae in Superconductivity

    E-Print Network [OSTI]

    A Simple Derivation of Josephson Formulae in Superconductivity Izumi OJIMA Research Institute of superconductivity in use of off­diagonal long range order (ODLRO). 1 Introduction According to the pioneering paper effect ( ~ B = 0 inside of superconductor) [4]. Inspired by these attempts to understand the essential

  1. DESIGN REQUIREMENTS AND OPTIONS FOR FINAL FOCUSING SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    California at San Diego, University of

    DESIGN REQUIREMENTS AND OPTIONS FOR FINAL FOCUSING SUPERCONDUCTING MAGNETS OF HEAVY-ION DRIVERS L of using both high-temperature superconductors and con- ventional low-temperature superconductors are investi- gated. The use of high-temperature superconducting materials may offer an attractive, although

  2. ORNL/HTSPC-20 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM

    E-Print Network [OSTI]

    ORNL/HTSPC-20 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM SUPERCONDUCTIVITY FOR ELECTRIC SYSTEMS ANNUAL...................................................................................................... 4-32 Section 5: Technical R&D and Support American Superconductor Corp. 2G wire development.................................................................... 5-4 NIST-Boulder electromechanical studies for superconductor development subcontract............ 5

  3. 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.

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

    DOE Patents [OSTI]

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

    2007-01-09T23:59:59.000Z

    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.

  5. Superconducting magnetic energy storage for asynchronous electrical systems

    DOE Patents [OSTI]

    Boenig, H.J.

    1984-05-16T23:59:59.000Z

    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.

  6. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (5519 S. Bruner, Hinsdale, IL 60521); Uherka, Kenneth L. (830 Ironwood, Frankfort, IL 60423); Abdoud, Robert G. (13 Country Oaks La., Barrington Hills, IL 60010)

    1996-01-01T23:59:59.000Z

    A high temperature superconducting bearing including a permanent magnet rotor levitated by a high temperature superconducting structure. 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.

  7. Algorithms for transform selection in multiple-transform video compression

    E-Print Network [OSTI]

    Cai, Xun, S.M. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Selecting proper transforms for video compression has been based on the rate-distortion criterion. Transforms that appear reasonable are incorporated into a video coding system and their performance is evaluated. This ...

  8. Crossover from a pseudogap state to a superconducting state

    E-Print Network [OSTI]

    Tian De Cao

    2011-02-10T23:59:59.000Z

    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.

  9. First Characterization of a Fully Superconducting RF Photoinjector Cavity

    SciTech Connect (OSTI)

    Neumann, A; Barday, R; Jankowiak, A; Kamps, T; Knobloch, J; Kugeler, O; Matveenko, A N; Quast, T; Rudolph, J; Schubert, S G; Volker, J; Kneisel, P; Nietubyc, R; Sekutowicz, J K; Smedley, J; Volkov, V; Weinberg, G

    2011-09-01T23:59:59.000Z

    As a first step towards a high brightness, high average current electron source for the BERLinPro ERL a fully superconducting photo-injector was developed by HZB in collaboration with JLab, DESY and the A. Soltan Institute. This cavity-injector ensemble is made up of a 1.6-cell superconducting cavity with a superconducting lead cathode deposited on the half-cell backwall. A superconducting solenoid is used for emittance compensation. This system, including a diagnostics beamline, has been installed in the HoBiCaT facility to serve as a testbed for beam dynamics studies and to test the combination SRF cavity and superconducting solenoid. This paper summarizes the characterization of the cavity in this configuration including Q measurements, dark current tests and field-stability analyses.

  10. Damping in high-temperature superconducting levitation systems

    DOE Patents [OSTI]

    Hull, John R. (Sammamish, WA)

    2009-12-15T23:59:59.000Z

    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.

  11. Niobium superconducting nanowire single-photon detectors

    E-Print Network [OSTI]

    Annunziata, Anthony J; Chudow, Joel D; Frunzio, Luigi; Rooks, Michael J; Frydman, Aviad; Prober, Daniel E

    2009-01-01T23:59:59.000Z

    We investigate the performance of superconducting nanowire photon detectors fabricated from ultra-thin Nb. A direct comparison is made between these detectors and similar nanowire detectors fabricated from NbN. We find that Nb detectors are significantly more susceptible than NbN to thermal instability (latching) at high bias. We show that the devices can be stabilized by reducing the input resistance of the readout. Nb detectors optimized in this way are shown to have approximately 2/3 the reset time of similar large-active-area NbN detectors of the same geometry, with approximately 6% detection efficiency for single photons at 470 nm.

  12. Vacuum coupling of rotating superconducting rotor

    DOE Patents [OSTI]

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

    2003-12-02T23:59:59.000Z

    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.

  13. Dual Superconductivity in G2 group

    E-Print Network [OSTI]

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

    2006-09-28T23:59:59.000Z

    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.

  14. Quantum State Synthesis of Superconducting Resonators

    E-Print Network [OSTI]

    Roshan Sharma; Frederick W. Strauch

    2015-03-07T23:59:59.000Z

    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.

  15. Superconducting Hair on Charged Black String Background

    E-Print Network [OSTI]

    Lukasz Nakonieczny; Marek Rogatko

    2012-01-25T23:59:59.000Z

    Behaviour of Dirac fermions in the background of a charged black string penetrated by an Abelian Higgs vortex is elaborated. One finds the evidence that the system under consideration can support fermion fields acting like a superconducting cosmic string in the sence that a nontrivial Dirac fermion field can be carried by the system in question. The case of nonextremal and extremal black string vortex systems were considered. The influence of electric and Higgs charge, the winding number and the fermion mass on the fermion localization near the black string event horizon was studied. It turned out that the extreme charged black string expelled fermion fields more violently comparing to the nonextremal one.

  16. Liquid Metal Transformers

    E-Print Network [OSTI]

    Sheng, Lei; Liu, Jing

    2014-01-01T23:59:59.000Z

    The room temperature liquid metal is quickly emerging as an important functional material in a variety of areas like chip cooling, 3D printing or printed electronics etc. With diverse capabilities in electrical, thermal and flowing behaviors, such fluid owns many intriguing properties that had never been anticipated before. Here, we show a group of unconventional phenomena occurring on the liquid metal objects. Through applying electrical field on the liquid metals immersed in water, a series of complex transformation behaviors such as self-assembling of a sheet of liquid metal film into a single sphere, quick mergences of separate metal droplets, controlled self-rotation and planar locomotion of liquid metal objects can be realized. Meanwhile, it was also found that two accompanying water vortexes were induced and reliably swirled near the rotating liquid metal sphere. Further, effects of the shape, size, voltage, orientation and geometries of the electrodes to control the liquid metal transformers were clar...

  17. Transformations of Heun's equation and its integral relations

    E-Print Network [OSTI]

    Léa Jaccoud El-Jaick; Bartolomeu D. B. Figueiredo

    2011-01-26T23:59:59.000Z

    We find transformations of variables which preserve the form of the equation for the kernels of integral relations among solutions of the Heun equation. These transformations lead to new kernels for the Heun equation, given by single hypergeometric functions (Lambe-Ward-type kernels) and by products of two hypergeometric functions (Erd\\'elyi-type). Such kernels, by a limiting process, also afford new kernels for the confluent Heun equation.

  18. Quantum Fourier transform and tomographic Renyi entropic inequalities

    E-Print Network [OSTI]

    M. A. Man'ko; V. I. Man'ko

    2009-02-25T23:59:59.000Z

    Renyi entropy associated with spin tomograms of quantum states is shown to obey to new inequalities containing the dependence on quantum Fourier transform. The limiting inequality for the von Neumann entropy of spin quantum states and a new kind of entropy associated with quantum Fourier transform are obtained. Possible connections with subadditivity and strong subadditivity conditions for tomographic entropies and von Neumann entropies are discussed.

  19. FOURIER TRANSFORM MULTIPLE QUANTUM NMR

    E-Print Network [OSTI]

    Drobny, G.

    2011-01-01T23:59:59.000Z

    of transition observed in Fourier transform multiple quantumDecember 18-19, 1979 FOURIER TRANSFORM MULTIPLE QUANTUM NMRof London, December 1978. FOURIER TRANSFO~~ MULTIPLE QUANTUM

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

    E-Print Network [OSTI]

    1979-01-01T23:59:59.000Z

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