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Note: This page contains sample records for the topic "limiting fcl superconducting" from the National Library of EnergyBeta (NLEBeta).
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1

High-temperature superconducting magnet for use in saturated core FCL  

Science Journals Connector (OSTI)

A HTS magnet system used in a saturated core Fault Current Limiter (FCL) device is described. The superconducting magnet, operating in DC mode, is used in such FCL design for saturating the magnetic core and maintaining low device impedance under nominal conditions. The unique design of the FCL poses constrains on the DC HTS magnet. A model which meets all the necessary special requirements have been realized in a compact magnet design that is optimized for its electrical characteristics while minimizing its mass and volume. The coil, made of Bi-2223 tapes, has 50000 Ampere-turns required to maintain the core in a saturated state at nominal current in the limiting circuit. Unique, nonmagnetic cryostat made of Delrin was used. Cooling of the coil has been realized by two cold heads: one double-stage head that provides a cooling power of 6 W at 20 K and a single-stage head with a cooling capability of 40W at 70 K. This magnetic system has been successfully integrated and tested in a 120 kVA FCL model. The design, characteristics and tests of this magnetic system are described.

Z Bar-Haim; A Friedman; Y Wolfus; V Rozenshtein; F Kopansky; Z Ron; E Harel; N Pundak; Y Yeshurun

2008-01-01T23:59:59.000Z

2

Controllable resistive type fault current limiter (CR-FCL) with frequency and pulse duty-cycle  

Science Journals Connector (OSTI)

Abstract In this paper a controllable resistive type fault current limiter (CR-FCL) is introduced. The CR-FCL inserts a pre-specified value of resistance based on a pre-defined function, by using a simple switching method, in series with the fault current path. When a fault occurs, a self turn off switch starts switching with a pre-specified frequency and duty cycle. By this switching pattern, the controlled value of resistance enters to the fault current path. So, the CR-FCL limits the fault current to the desired values. In addition, from transient stability point of view, by inserting the optimal resistance value, the CR-FCL is capable to enhance power system transient stability in a good manner. In fact, generation of the controllable resistance that depends on the duty cycle of the self turn off switch is the main idea of the CR-FCL. The variable duty cycle results the variable resistance and the fixed duty cycle results the fixed resistance. Analytical analyses of the proposed FCL are presented in details. Simulation results by power system computer-aided design/electromagnetic transients, including dc (PSCAD/EMTDC) software and corresponding experimental results are studied to validate the effectiveness of the CR-FCL. Considering error analyses, there is the good agreement between the simulation results and the experimental results.

Seyed Behzad Naderi; Mehdi Jafari; Mehrdad Tarafdar Hagh

2014-01-01T23:59:59.000Z

3

Superconducting fault current limiter with fast vacuum commutation modulus  

Science Journals Connector (OSTI)

A new approach to a problem of creation of a resistive version of superconducting fault current limiters (FCL) on the basis of HTS materials has been considered. According to this approach, a scheme of FCL is added by a commutation modulus which contains a fast vacuum interrupter. This interrupter allows one to switch off the transport current as soon as 5 ms after transition of the HTS element to the normal state. The proposed scheme allows one to restrict more than an order in value a necessary operation time of FCL in a regime of a current limitation. As a result, a time of recovering the superconducting state can be significantly reduced that allows FCL to operate in automatic iterative regime. The considering device can operate not only in high voltage ac transmission lines but also in dc electrical networks. A numerical simulation of transit processes in a proposed scheme of FCL has been performed for different regimes and its features are analyzed with respect to other schemes of FCL. An experimental study of test mock-up commutation elements of FCL has been performed. This study demonstrates an efficiency of the proposed scheme. A test of a FCL model with the limiting current up to 15 kA has been realized.

D Alferov; D Yevsin; L Fisher; V Ivanov; V Sidorov

2008-01-01T23:59:59.000Z

4

Fault Current Limit (FCL) Technology (Magnetic Valve Controlled Reactor-Type Fault Current Limiter Principle and Simulation)  

Science Journals Connector (OSTI)

Summarized the FCL practical research which faces to the key technical problems, briefly introduces the study of magnetic valve controllable reactor type fault current limiter principle, and the simulation result...

Chunzhe Shi

2012-01-01T23:59:59.000Z

5

Fault current limiting and voltage sag mitigation by means of a resonant type FCL  

Science Journals Connector (OSTI)

In this paper a resonant type of fault current limiter and its application are presented. During normal operation of circuit, the thyristors is off and the resonant branches are short circuit. Therefore there is not any voltage drop on FCL. In this way, ... Keywords: bypass resistance, fault analysis, power quality, resonant type fault current limiter

M. S. Mohebbi Nazar; M. Abapour

2006-08-01T23:59:59.000Z

6

A Conceptual Design of Superconducting Fault Current Limiter with Bi2223 in 6.6 kV Distribution System  

Science Journals Connector (OSTI)

We have proposed a new type fault current limiter, which consists of a flux-lock reactor...c...superconducting (HTS) element and ac magnetic field coil (Flux-Lock Type Fault Current Limiter: FLT-FCL). This paper ...

Yu-Hong Guo; Toshiyuki Uchii; Yasunobu Yokomizu…

1998-01-01T23:59:59.000Z

7

Operating principle of a high Tc superconducting saturable magnetic core fault current limiter  

Science Journals Connector (OSTI)

An electrical fault current limiter (FCL) designed with a high Tc superconducting (HTS) dc bias winding is described. The winding is prepared by using a Ag-clad (Bi,Pb)2Sr2Ca2Cu3O10+x HTS wire. The limiting behaviour of this FCL is investigated and considered with respect to operation in a 6 kV power system. The results show that the FCL limits fault currents effectively, and is a possible solution for reducing power system fault currents.

J.X. Jin; S.X. Dou; C. Grantham; D. Sutanto; H.K. Liu

1997-01-01T23:59:59.000Z

8

9 - Superconducting fault current limiters and power cables  

Science Journals Connector (OSTI)

Abstract: This chapter addresses the technology of superconducting power cables and superconducting fault current limiters (FCL). The first part of the chapter is a general summary of the electric power grid. This sets the stage for a discussion of the historical development of superconducting AC and DC cables, which begins with low temperature superconductor (LTS)-based systems. It then describes the present status of superconducting cable technology and summarizes some of the major programs around the world. Whereas power cables may be thought of as a replacement for conventional power system components, \\{FCLs\\} and fault current controllers (FCC) have no conventional equivalent in the power grid. Several conceptually different FCL designs are described. The status of their development and installation on the power grid are described.

W. Hassenzahl

2013-01-01T23:59:59.000Z

9

Superconducting fault current limiter for power utility application  

SciTech Connect

Recent accomplishments in the development of superconducting fault current limiters for power systems are outlined. These accomplishments include the comprehensive requirement for fault current limiters developed by SCE; down-selection; bridge concepts; shunt concepts; and high resistivity matrix substrates for HTS conductors. The proposed Phase II SPI-FCL Program is outlined. It is concluded that the SPI fault current limiter program will benefit both the power utility industry as well as the high temperature superconductivity community and progress of Phase I is right on target.

Leung, E. [Martin Marietta Corp., Oak Ridge, TN (United States)

1994-07-29T23:59:59.000Z

10

High Temperature Superconducting Fault Current Limiter for Utility Applications  

Science Journals Connector (OSTI)

One of the most near term High Temperature Superconductor (HTS) applications is the Fault Current Limiter (FCL). It is a device that...

E. M. W. Leung; G. W. Albert; M. Dew…

1997-01-01T23:59:59.000Z

11

Development of Superconducting AC Fault Current Limiter  

Science Journals Connector (OSTI)

The authors have developed a new superconducting fault current limiter whose impedance during normal operation is very small. During fault conditions, the limiter behaves as a superconducting reactor. The limiter

Daisuke Ito; Eriko Yoneda; Tsutomu Fujioka…

1990-01-01T23:59:59.000Z

12

Test on Superconducting AC Fault Current Limiter  

Science Journals Connector (OSTI)

The authors have developed a new superconducting fault current limiter whose impedance during normal operation is very small. During fault conditions, the limiter behaves as a superconducting reactor. The limiter

Daisuke Ito; Eriko S. Yoneda…

1990-01-01T23:59:59.000Z

13

A Study of a High-Tc Superconducting Fault Current Limiter (No. 2): Development of an Element for 100-V Class Power Systems  

Science Journals Connector (OSTI)

The application of a high critical temperature (Tc) superconductor with a high critical current density (Jc) to a fault current limiter (FCL) was investigated to obtain a FCL which exhibits superior current limit...

Tatsuya Hayashi; Teijiro Mori; Yuuichi Wada…

1993-01-01T23:59:59.000Z

14

Summary of Superconducting Fault Current Limiter Technology  

Science Journals Connector (OSTI)

In recent years, superconducting fault current limiter (SFCL) has become one of the forefront topics of current-limiting technology in the world. In this...

Linmang Wang; Pengzan Jiang; Dada Wang

2012-01-01T23:59:59.000Z

15

Study of Superconducting Fault Current Limiter Using Saturated Magnetic Core  

Science Journals Connector (OSTI)

This paper presents a saturated magnetic core superconducting current limiter (SCSFCL) operation simulation results using finite element technique. The superconducting current limiter uses BSCCO tape to produce m...

F. Fajoni; E. Ruppert; C. A. Baldan…

2014-11-01T23:59:59.000Z

16

Magnetic saturable reactor type HTS fault current limiter for electrical application  

Science Journals Connector (OSTI)

An electrical fault current limiter (FCL) developed based on the principle of a magnetic saturable reactor requires a high current ampere-turn coil as its dc bias, and this coil is necessary to use a high temperature superconducting (HTS) winding. This HTS FCL has been studied, and identified with several advantages compared to other HTS FCLs, and therefore is further considered for its practical industry application.

J.X. Jin; S.X. Dou; C. Cook; C. Grantham; M. Apperley; T. Beales

2000-01-01T23:59:59.000Z

17

Observation of Transient Behavior of Magnetic Flux in Inductive-type Fault Current Limiter with YBCO Thin Film Disc  

Science Journals Connector (OSTI)

Recently, the installation of fault current limiters (FCLs) in power systems is expected for controlling large short circuit currents. In this study, we focus on inductive-type \\{FCLs\\} having a YBCO superconducting thin film disc that is fabricated by metal-organic deposition. AC currents were injected into the FCL so that the periodic transient behavior of the apparent magnetic flux density around the FCL could be measured by using a pick-up coil. The magnetic flux density exhibited hysteresis when AC current was injected into the FCL. The transition between the conducting states in the YBCO layer was explained by the hysteresis relationship between the magnetic flux density and current.

Kosuke Higuchi; Yin Guan; Yasunobu Yokomizu; Toshiro Matsumura

2012-01-01T23:59:59.000Z

18

Modeling and Simulation of Resistive Superconducting Fault-Current Limiters  

Science Journals Connector (OSTI)

Superconducting fault-current limiters (SFCL) offer ideal performance in electrical ... simulation model for a novel resistive type superconducting fault-current limiter is proposed. This model includes the elect...

S. Nemdili; S. Belkhiat

2012-10-01T23:59:59.000Z

19

Superconducting Fault Current Limiter for Transmission Voltage  

Science Journals Connector (OSTI)

Within a collaboration of American Superconductor, Siemens, Nexans and Southern California Edison one electrical phase of a resistive superconducting fault current limiter for the 115 kV transmission voltage level has been designed and manufactured. The active part of the limiter consists of 63 bifilar coils made of 12 mm wide steel-stabilized YBCO conductor and is housed in a cryostat operated at 5 bar and 74 K. The first phase was completely assembled and successfully subjected to power switching tests and high voltage tests. The basic design of the system and the test results are reported. The work was funded in part by US-DOE under Contract Number DE-FC26-07NT43243.

Hans-Peter Kraemer; Wolfgang Schmidt; Hong Cai; Bruce Gamble; David Madura; Tim MacDonald; Joe McNamara; Walther Romanosky; Greg Snitchler; Nicolas Lallouet; Frank Schmidt; Syed Ahmed

2012-01-01T23:59:59.000Z

20

Superconducting fault-current limiter and inductor design  

SciTech Connect

A superconducting fault current limiter (SFCL) that uses a biased superconducting inductor in a diode or thyristor bridge circuit was analyzed for transmission systems in 69, 138, and 230 rms kV utility transmission systems. The limiter was evaluated for costs with all components - superconducting coil, diode and/or SCR power electronics, high voltage insulation, high voltage bushings and vapor cooled leads, dewar, and refrigerator - included. A design was undertaken for the superconducting cable and coils for both diode and SCR 69 kV limiter circuits.

Rogers, J.D.; Boenig, H.J.; Chowdhuri, P.; Schermer, R.I.; Wollan, J.J.; Weldon, D.M.

1982-01-01T23:59:59.000Z

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


21

A dc superconducting fault current limiter using die-pressed  

Science Journals Connector (OSTI)

A model of a superconducting fault current limiter on a polycrystalline high-temperature superconductor basis is checked in the dc short circuit regime. Protection of load takes place under the conditions described in this paper. The use of ceramic materials with superconducting-normal metal-superconducting Josephson junction network having an S-type current-voltage characteristic (CVC) is shown to be effective for fault current limiter devices.

A G Mamalis; M I Petrov; D A Balaev; K A; D M Gohfeld; S V Militsyn; S G; V I Kirko; I N Vottea

2001-01-01T23:59:59.000Z

22

8 - Superconducting fault current limiters and power cables  

Science Journals Connector (OSTI)

Abstract: This chapter addresses the technology of superconducting power cables and superconducting fault current limiters. The first part of the chapter is a general summary of the electric power grid. This sets the stage for a discussion of the historical development of superconducting AC and DC cables, which begins with low temperature superconductor-based systems. It then describes the present state of superconducting cable technology and gives a summary of some of the major programs around the world. Whereas power cables may be thought of as a replacement for conventional power system components, fault current limiters and fault current controllers have no conventional equivalent in the power grid. Several conceptually different fault current limiter designs are described. Their state of development and installation on the power grid are described.

W. Hassenzahl

2012-01-01T23:59:59.000Z

23

Microsoft Word - FCL Testing Report Final.doc  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

An Assessment of Fault Current Limiter An Assessment of Fault Current Limiter Testing Requirements Prepared for U.S. Department of Energy Office of Electricity Delivery and Energy Reliability Prepared by Brian Marchionini and Ndeye K. Fall, Energetics Incorporated Michael "Mischa" Steurer, Florida State University February 2009 Energetics Incorporated i EXECUTIVE SUMMARY The U.S. Department of Energy's (DOE) Office of Electricity Delivery and Energy Reliability (OE) is conducting research and development (R&D) on next-generation electricity delivery equipment including fault current limiters (FCLs). Prototype FCL devices are undergoing testing with the aim of market-ready devices making their debut in the transmission and distribution (T&D) system in the next five years. As these

24

New Concept of a Superconducting Fault Current Limiter and Its Evaluation of Quenching Feature  

Science Journals Connector (OSTI)

The present paper reviews the concept of a new superconducting fault current limiter with NbTi AC superconducting wire for the suppression of short-circuit currents. This fault current limiter takes full advantag...

Kiyoshi Okaniwa; Tsukushi Hara; Takahiko Yamamoto…

1991-01-01T23:59:59.000Z

25

Dynamic Inductance in Saturated Cores Fault Current Limiters  

Science Journals Connector (OSTI)

The saturated cores Fault Current Limiter (FCL) is one of the leading ... for providing a commercial robust solution to the fault current problem. Basically, the saturated cores FCL ... its saturated cores state ...

Y. Nikulshin; Y. Wolfus; A. Friedman…

2014-09-01T23:59:59.000Z

26

A transformer type fault current limiter with spark gap  

Science Journals Connector (OSTI)

A novel fault current limiter (FCL) is proposed in this paper. ... of the capacitor. During the short-circuit faults, the FCL resonantly produces a high impedance in the fault circuit after the breakdown of the s...

Zhang Xiaoqing; Ming Li

2010-06-01T23:59:59.000Z

27

Bias current influence on the characteristic of the magnetic-controlled switcher type fault current limiter  

Science Journals Connector (OSTI)

A novel magnetic-controlled switcher type fault current limiter (FCL) for high voltage electric network is presented. The current limiting principle of the FCL and the bias current influence on the characteristic...

Yan-xia Pan ???; Jian-guo Jiang ???

2009-06-01T23:59:59.000Z

28

Radiation-effects limits on copper in superconducting magnets  

SciTech Connect

The determination of the response of copper stabilizers to neutron irradiation in fusion-reactor superconducting magnets requires information in four areas: (1) neutron flux and spectrum determination, (2) resistivity changes at zero field, (3) resistivity changes at field, and (4) the cyclic irradiation and annealing. Applications of our current understanding of the limits of copper stabilizers in fusion-reactor designs are explored in two examples. Recommendations for future additions to the data base are discussed.

Guinan, M.W.

1983-05-25T23:59:59.000Z

29

Definition: Fault Current Limiter | Open Energy Information  

Open Energy Info (EERE)

Limiter Limiter Jump to: navigation, search Dictionary.png Fault Current Limiter A fault current limiter prevents current in an electrical circuit from exceeding a predetermined level by increasing the electrical impedance of that circuit before the current through the circuit exceeds that level. Fault current limiters are designed so as to minimize the impedance of the circuit under normal conditions to reduce losses, but increase the impedance of the circuit under fault conditions to limit fault current.[1] View on Wikipedia Wikipedia Definition A Fault Current Limiter (FCL) is a device which limits the prospective fault current when a fault occurs (e.g. in a power transmission network). The term includes superconducting devices and non-superconducting devices, however some of the more simple non-superconducting devices (such

30

Limiting characteristics of the superconducting fault current limiter applied to the neutral line of conventional transformer  

Science Journals Connector (OSTI)

Abstract The increased electricity demands influenced by the recent industrial development make the electric power distribution system more comprehensive, and the risks are high to cause failures to steady state electric line due to the extended range of fault at the time of fault occurrence. Also, the high performance and the high precision electric appliances that sensitive to switching surge and fault current expose vulnerability of reduced life span and increased fault occurrence ratio. Therefore, this thesis analyzed the fault limiting characteristics by the fault types by applying the superconducting fault current limiter to the neutral line of the transformer in order to reduce the fault currents that flow such high performance appliances. A current transformer (CT) that detects the fault current in the simulated power distribution system, a switching control system that is self-developed and a transformer are used in constructing a circuit. When a fault occurs, the initial fault current is restricted by the superconducting fault current limiter and simultaneously detours the fault current by operating the SCR contact of the switching control system through the detection by CT. This thesis analyzed the limiting characteristics of the superconducting fault current limiter that are applied to the neutral line of the transformer by the fault types.

I.G. Im; H.S. Choi; B.I. Jung

2013-01-01T23:59:59.000Z

31

Experimental study on characteristics of superconducting fault current limiters connected  

Science Journals Connector (OSTI)

Superconducting fault current limiters (SCFCLs) can reduce fault current; thus SCFCLs allow the capacity of circuit breakers to be reduced and lend flexibility to power system network designs. Furthermore, SCFCLs are expected to improve power system stability, as has been confirmed by some experiments. Therefore, various kinds of SCFCLs were proposed and have been studied. For introducing SCFCLs in power systems, there should be some specifications, such as the impedance, the trigger current level, and the recovery time. Fault analyses pointed out that accuracy of the trigger current level is required. A transformer type SCFCL with an adjustable trigger current level was proposed, designed, made, and tested. Then, limiting tests on three-phase SCFCLs by use of an artificial transmission line with a small generator were carried out. The test results indicated that at phase-to-phase faults, the SCFCLs for the fault phases do not always turn into the limiting mode. From two points of view, it is important to study characteristics of the series connection for SCFCLs: one is as mentioned above, and the other is that a series connection of some SCFCLs of small impedance may be installed in place of an SCFCL of larger impedance. This paper describes the results of limiting tests on two SCFCLs connected in series. The tests were carried out under some different conditions of fault currents, fault phases, and trigger current levels of SCFCLs. Some discussion on characteristics of series connection of SCFCLs appears also.

Hiroyuki Hatta; Tanzo Nitta; Tomomi Oide; Masakuni Chiba; Yasuyuki Shirai; Akihiro Mochida

2004-01-01T23:59:59.000Z

32

Proposal of DC shield reactor type superconducting fault current limiter  

Science Journals Connector (OSTI)

Saturated DC reactor type superconducting fault current limiter (SFCL) had been proposed two years ago. It was classified to rectifier type SFCL. The changing inductance value with the operating mode has superior characteristics to reduce voltage sag during step increase of the load current. But it has the disadvantage of its weight. In this paper, rectifier type SFCL with shielded reactor has been proposed. The reactor which has superconducting ring or tube inside its winding is substituted to the DC link of the rectifier. The configuration looks like an air core transformer with secondary short winding. When the current through the bulk shield-ring reaches to a certain level, the flux penetrates to the shield body and finite impedance appears in the primary winding. In other words, when the surface flux density exceeds its critical flux density, the flux penetrates into the bulk superconductor, and increases equivalent inductance. The equivalent transient resistance of the shield was represented as a function of exponential of the time. Using this equivalent transient resistance, the transient impedance was expressed. The transient wave analysis using EMTDC (electro-magnetic transients in DC systems) has been described. Simulated waveforms are shown considering the source inductance, the leakage inductance, the coupling coefficient and the forward voltage drop of the semiconductor. And voltage sag was also investigated with 50% step load increase. Preliminary design was also performed. The coil size and number of turns are designed to obtain adequate inductance for the current limitation, and the central magnetic field of the coils are calculated. There is optimal aspect ratio to minimize the magnetic field with restriction in outer diameter of the coil.

Itsuya Muta; Tsutomu Hoshino; Khosru Mohammad Salim; Akio Kawasaki; Taketsune Nakamura; Masato Yamada

2004-01-01T23:59:59.000Z

33

Basic Test of A 3-Phase Superconducting Fault Current Limiting Reactor  

Science Journals Connector (OSTI)

A novel 3-phase superconducting fault current limiting reactor (SCFCLR) for power system ... some experiments, the fundamental behavior of the limiter is confirmed. In the experiment, two ... exhibits very small ...

H. Kado; T. Ishigohka

1990-01-01T23:59:59.000Z

34

25 kV Superconducting Fault Current Limiter  

Science Journals Connector (OSTI)

Our technological progress in die field of superconductivity over the last ten years made possible the manufacture of industrial lengths of conductors, consisting of NbTi ultra-fine filaments, embedded in a Cu-30...

T. Verhaege; J. P. Tavergnier; A. Février…

1990-01-01T23:59:59.000Z

35

Design and current-limiting simulation of magnetic-shield type superconducting fault current limiter with high-Tc superconductors  

SciTech Connect

The continuous development of electric power utilities has led to the increase in the problems concerning fault currents. The use of fault current limiters, which suppress fault currents below a prescribed level, has been examined in many places. The authors have studied a superconducting fault current limiter that is based on the magnetic shielding effect of superconductors. In this paper, the authors derive a requirement for leading to a flux-jumping inside a ceramic superconductor at liquid nitrogen temperature. Next, two kinds of magnetic-shield type superconducting fault current limiters are designed, and their current-limiting simulations are tried using a computer.

Kajikawa, K.; Kaiho, K.; Tamada, N. [Electrotechnical Lab., Tsukuba, Ibaraki (Japan)] [Electrotechnical Lab., Tsukuba, Ibaraki (Japan); Onishi, T. [Hokkaido Univ., Sapporo (Japan)] [Hokkaido Univ., Sapporo (Japan)

1996-07-01T23:59:59.000Z

36

Quenching Characteristics of a 400V-100A Class Superconducting Fault Current Limiter  

Science Journals Connector (OSTI)

The suppression of large fault currents in large electric power systems constitutes an ... previously proposed a conceptually new type of superconducting fault current limiter and its application to model distrib...

Takeshi Okuma; Tsukushi Hara; Takahiko Yamamoto…

1992-01-01T23:59:59.000Z

37

Numerical Analysis of Overvoltage and Accumulated Energy at Quenching in Superconducting Fault Current Limiters  

Science Journals Connector (OSTI)

The present paper is devoted to a discussion of the overvoltage and accumulated energy which constitute problems when superconducting fault current limiters are introduced into electric power systems. These ... b...

S. Honjo; T. Hara; T. Yamamoto

1994-01-01T23:59:59.000Z

38

Electrothermal Modeling of Coated Conductor for a Resistive Superconducting Fault-Current Limiter  

Science Journals Connector (OSTI)

Coated conductors are very promising for the design of a novel and efficient superconducting fault-current limiter (SFCL). The thermal and electrical behaviors ... of SFCL in the presence of over-critical currents

S. Nemdili; S. Belkhiat

2013-08-01T23:59:59.000Z

39

1.2 MVA High-Tc Superconducting Fault Current Limiter  

Science Journals Connector (OSTI)

A 3-phase high Tc superconducting fault current limiter with a rated power of 1.2 ... a special partial melt process. The nominal current and voltage of the device are 70 ... 3-phase short circuit tests with a pr...

W. Paul; M. Chen; M. Lakner; J. Rhyner; L. Widenhorn…

1998-01-01T23:59:59.000Z

40

Coated conductor arrangement for reduced AC losses in a resistive-type superconducting  

Science Journals Connector (OSTI)

The basic element of a resistive superconducting fault current limiter (FCL) can consist of coated conductor tape exceeding a few meters in length and compacted into a cryogenic envelope. This paper is focused on optimizing the arrangement of coated conductors with a non-magnetic substrate for a resistive superconducting FCL. Several configurations have been tested experimentally and theoretically. Two low-loss arrangements have been identified, both utilizing the bifilar configuration, i.e. the currents in two adjacent tapes are identical in amplitude but opposite in direction. The separation between two adjacent tapes s varied from 0.07 up to 2.10 mm. For the lowest examined separation s the AC transport loss of the straight bifilar model decreased by more than one order with respect to the AC transport loss in the single-tape configuration. Further AC loss decrease is achieved when the pair of tapes carrying opposite currents forms a flat pancake coil. We developed a numerical model in order to analyze the influence of distance between adjacent tapes. To achieve agreement between experimental and numerical results it was necessary to incorporate a lateral distribution of critical current density in the tape. The remaining differences between the results of experiment and calculation can be explained by analysis of experimental imperfections. Finally we suggest an empirical fit for the prediction of AC loss of a practical superconducting fault current limiter.

J Šouc; F Gömöry; M Vojen?iak

2012-01-01T23:59:59.000Z

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


41

Recovery time of superconducting non-inductive reactor type fault current limiter  

SciTech Connect

A superconducting fault current limiting device for electric power systems has been investigated to find out its feasibility. Non-inductive reactor type fault current limiter has been constructed using metal superconductor. Two bifilar wound solenoids were connected in antiparallel or antiseries. On each connection, the fault current limiting test was performed by short-circuiting a resistive load suddenly. The recovery (normal-to-superconductive state transition) time after the current limiting mode has been studied using small scale model of fault current limiter for the low voltage distribution line. The results reveal that the current limiter could be operated under repetitive fault current accident which was removed within a few cycle of the limiting mode. The recovery time is a function of the dissipated energy under current limiting mode. Test results are presented.

Hoshino, T.; Muta, I.; Tsukiji, H. [Saga Univ., Honjo, Saga (Japan)] [Saga Univ., Honjo, Saga (Japan); Ohkubo, K.; Etoh, M. [Kyushu Electric Power Co., Kono-Higashi, Saga (Japan)] [Kyushu Electric Power Co., Kono-Higashi, Saga (Japan)

1996-07-01T23:59:59.000Z

42

Development of 6.6kV/1.5kA-Class Superconducting Fault Current Limiter  

Science Journals Connector (OSTI)

The authors have developed and tested a 6.6kV/l.5kA-class superconducting fault current limiter, wound with an AC superconducting wire having ... up to 6.6kV were applied to the limiter. The limiter was able to s...

Kenji Tasaki; Kazuyuki Turunaga; Daisuke Ito…

1992-01-01T23:59:59.000Z

43

A Magnetic Shielding Type Superconducting Fault-Current Limiter  

Science Journals Connector (OSTI)

In a Magnetic Shielding type Fault-Current Limiter (MSFCL), the characteristics of the magnetic ... ) is an important factor in limiting the current flow. In this study, to improve the efficiency of the fault current

N. Miyauchi; H. Nakane; S. Haseyama; S. Yoshizawa

1999-01-01T23:59:59.000Z

44

Design and Test Results of a 1 MVA Resistive Type Fault Current Limiter  

Science Journals Connector (OSTI)

The 1 MVA resistive type single phase AC fault current limiter (FCL) was build and successfully tested by capacitors battery discharge. FCL rated voltage is 3.5 kV, current 250 Arms. The 240 m of HTS tape (type SF12100 by SupePower) was used for FCL production. The FCL consists of 8 bifilar coils each wound onto glass-fiber 70 mm diameter tube and connected in series. The HTS tapes were additionally stabilized with Cu laminated highly resistive foil. During the tests of separate FCL coils at 380 V an excellent limiting performance was observed. Tested FCL coil was switched off after 75 ms, the maximum temperature at the HTS tape was less then 230 K, the recovery time was about 5 s.

V.E. Keilin; V.V. Lobyntsev; M.S. Novikov; S.J. Novikov; V.I. Shcherbakov

2012-01-01T23:59:59.000Z

45

Study On Magnetic Shielding Type Superconducting Fault Current Limiter Using Bi-Sr-Ca-Cu-O Cylinder  

Science Journals Connector (OSTI)

The power application of a superconductor to restrain a fault current has been researched. A superconducting fault current limiter using a Bi-Sr-Ca-Cu-O cylinder has been developed. This limiter consists of the p...

Michiharu Ichikawa; Hiroyuki Kado; Kunikazu Izumi

1994-01-01T23:59:59.000Z

46

Engineering Division Superconducting  

NLE Websites -- All DOE Office Websites (Extended Search)

10152014 Joseph V. Minervini 74 35 MW superconducting motor Superconducting Fault Current Limiter (SCFL) Technology & Engineering Division HTS (MgB 2 ) * DC superconducting...

47

A hybrid superconducting fault current limiter for enhancing transient stability in Korean power systems  

Science Journals Connector (OSTI)

Abstract Additional power generation sites have been limited in Korea, despite the fact load demands are gradually increasing. In order to meet these increasing demands, Korea’s power system company has begun constructing new generators at existing sites. Thus, multi-unit plants can create problems in terms of transient stability when a large disturbance occurs. This paper proposes a hybrid superconducting fault current limiter (SFCL) application to enhance the transient stability of multi-unit power plants. \\{SFCLs\\} reduce fault currents, and limitation currents decrease the imbalance of the mechanical and electrical torque of the generators, resulting in an improvement in transient stability.

Sangsoo Seo; Seog-Joo Kim; Young-Hwan Moon; Byongjun Lee

2013-01-01T23:59:59.000Z

48

Development of a 220 kV/300 MVA superconductive fault current limiter  

Science Journals Connector (OSTI)

After we developed a saturated iron core type 35 kV/90 MVA superconductive fault current limiter and installed the device in a transmission network at Puji substation of China Southern Power Grid for live-grid operation in 2007, we continued our efforts in advancing this technology. A 220 kV/300 MVA device has been designed, manufactured and factory tested. This device differs from the 35 kV device in its form of electrical insulation even though the two devices have the same working principle and similar core structure. Improvements in the dc magnetization circuit and the cryogenic system were also achieved. This 220 kV/300 MVA superconductive fault current limiter has been installed and has passed all field tests at Shigezhuang substation in Tianjin, China. Trial operation is underway. This paper introduces the major design parameters, key functional specifications and some testing results of the device.

Y Xin; W Z Gong; H Hong; Y Q Gao; X Y Niu; J Y Zhang; Y W Sun; A L Ren; H Z Wang; L F Zhang; Q Li; Z Q Wei; L Z Wang; J B Cui; G J Niu; Z Q Xiong

2012-01-01T23:59:59.000Z

49

A superconducting fault current limiter integrated in the cold heat exchanger of a  

Science Journals Connector (OSTI)

In this work we probe a compact superconducting fault current limiter (SFCL) integrated in the cold heat exchanger of a thermoacoustic refrigerator. A design for an SFCL device with a power of about 2.2 kW is presented and described in detail. A thermoacoustic refrigerator is also proposed which, under fault conditions, must be able to remove around 50 W at 80 K. A simulation routine is run to test the performance of the SFCL, based on YBCO films, in terms of both the limiting capacity and the energy to be dissipated and removed inside the heat exchanger.

M R Osorio; A Bétrancourt; M X François; J A Veira; F Vidal

2008-01-01T23:59:59.000Z

50

Fault current limiter based on triggered vacuum switch  

Science Journals Connector (OSTI)

A new type of fault current limiter (FCL) based on triggered vacuum switch ... is mainly composed of a capacitor, a current-limiting reactor connected with a capacitor in ... behaves as a conventional series comp...

Jing Shi; Ji-yan Zou; Jun-jia He…

2000-12-01T23:59:59.000Z

51

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

SciTech Connect

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.

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

2005-04-13T23:59:59.000Z

52

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

DOE Patents (OSTI)

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

Boenig, Heinrich J. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

53

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

DOE Patents (OSTI)

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.

Boenig, H.J.

1982-08-16T23:59:59.000Z

54

Application of Hi-Tc superconducting current fault limiters to utility distribution networks  

SciTech Connect

A new classification of superconducting current fault limiter (SCFL) is described which is a non-quenching, variable-inductance-mode VIM current limiter with characteristics matched to utility distribution line parameters. A major application of this device is for replacement of fixed-inductance air-core reactors used in impedance and short-circuit levels from sub-transmission to distribution. The secondary application of the SCFL is for protection of distribution substation transformers in the 5--40 MVA range, as a replacement for current limiting fuses and air-blast circuit breakers. The SCFL devices have the unique characteristic of producing minimal or no transient recovery voltage (TRV) as is typical of conventional interruption technologies.

Kuznetsov, S.B.; Webb, T.J. [Power Superconducting Devices Inc., Pittsburgh, PA (United States)

1996-10-01T23:59:59.000Z

55

Design and Development of the First Polish Superconducting Fault Current Limiter For MV Distribution Systems  

Science Journals Connector (OSTI)

Superconducting fault current limiters (SFCL) are designed to protect the electrical grid from faults. The rapid increase of impedance of the SFCL reduces the short current in the circuit. In this paper, we present the design and development of coreless inductive SFCL for MV distribution systems. It is a very attractive design which reduces the weight of the device thanks to the coreless construction and the size of primary winding, reduced thanks to cryogenic cooling. The primary 2G HTS and secondary 2G HTS windings are magnetically coupled to one another. Copper primary winding connected parallely to the HTS primary winding is magnetically coupled to HTS windings and ensure that in cases of lack of cooling or superconductor failure, the protected circuit will not be disrupted. Tests performed at high power test facility shows the limiting performance of the coreless inductive SFCL.

Janusz Kozak; Michal Majka; Tadeusz Janowski; Slawomir Kozak

2012-01-01T23:59:59.000Z

56

Saturated iron-core superconductive fault current limiter developed at Innopower  

Science Journals Connector (OSTI)

Since 2002 we have been carrying out programs in developing Saturated Iron-core Superconducting Fault Current Limiters (SISFCLs). Innovative technologies were adopted in designing the iron-core and the magnetization circuit making our SISFCL more efficient useful and reliable. With our technology a 35 kV SISFCL with dry-type electrical insulation and a 220 kV SISFCL with oil electrical insulation were manufactured and installed for live-grid operation in 2008 and in 2012 respectively. Operation data and test results show that the performances of the devices meet design expectations and utility's needs. Our SISFCL is applicable for both transmission and distribution networks and can satisfy a wide range of fault current limiting impedance requirements.

2014-01-01T23:59:59.000Z

57

Modeling of Shield-Type Superconducting Fault-Current-Limiter Operation Considering Flux Pinning Effect on Flux and Supercurrent Density in High-Temperature Superconductor Cylinders  

Science Journals Connector (OSTI)

Superconducting fault current limiter, SFCL, forms an important category of fault-current-limiting devices which limit the short-circuit current levels in electrical networks. Therefore, modeling ... its main ope...

Arsalan Hekmati

2014-03-01T23:59:59.000Z

58

CRYOGENIC SYSTEM FOR A 35 KV/90 MVA SATURATED IRON?CORE SUPERCONDUCTING FAULT CURRENT LIMITER  

Science Journals Connector (OSTI)

A cryogenic system was built as an open system for a 35 kV/90 MVA saturated iron?core superconducting fault current limiter. It consists of an annular cylindrical liquid nitrogen dewar cryogenic pipes sensors valves and a control unit. A HTS dc bias coil was immersed with liquid nitrogen in the dewar. The control circuit constantly monitors the liquid nitrogen level and controls the supply of liquid nitrogen in accordance with the liquid nitrogen level change. Nitrogen vapor was directly released into the environment. Heat loss under different working conditions such as no magnetization current 150 A magnetization current and on?grid condition was measured to evaluate the performance of the system. As compared with no magnetization current of the dc bias coil evaporation of liquid nitrogen increases about 20% under the on?grid condition.

H. Hong; W. Z. Gong; B. Tian; J. Y. Zhang; X. M. Hu; J. Z. Wang; X. Y. Niu; Y. Wang; L. F. Zhang; Y. W. Sun; T. Q. Wu; Y. Xin

2010-01-01T23:59:59.000Z

59

Implementation of superconducting fault current limiter for flexible operation in the power substation  

Science Journals Connector (OSTI)

Abstract The concentration of large-scale power loads located in the metropolitan areas have resulted in high fault current levels during a fault thereby requiring the substation to operate in the double busbar configuration mode. However, the double busbar configuration mode results in deterioration of power system reliability and unbalanced power flow in the adjacent transmission lines which may result in issues such as overloading of lines. This paper proposes the implementation of the superconducting fault current limiter (SFCL) to be installed between the two substation busbars for a more efficient and flexible operation of the substation enabling both single and double busbar configurations depending on the system conditions for guaranteeing power system reliability as well as fault current limitations. Case studies are being performed for the effectiveness of the SFCL installation and results are compared for the cases where the substation is operating in single and double busbar mode and with and without the installation of the SFCL for fault current mitigation.

Chong Suk Song; Hansang Lee; Yoon-sung Cho; Jaewan Suh; Gilsoo Jang

2014-01-01T23:59:59.000Z

60

Thermal–electrical analogy for simulations of superconducting fault current limiters  

Science Journals Connector (OSTI)

Abstract In spite of the recent advances achieved with superconducting fault current limiters (SCFCL’s), modeling and simulation of such devices are still important issues. There are different approaches for modeling SCFCL’s, whereas computational simulations provide a better understanding of the behavior of SCFCL devices. In addition, results of hard experimental access may be achieved by means of computational simulation. The aim of this paper is to present a simple computational model to predict both the electrical and thermal behaviors of SCFCL devices. The main contribution of the present work is the use of a thermal–electrical analogy to solve the heat transfer equations inside SCFCL sub-components, which enables one to handle with relative easy the strong and nonlinear coupling between thermal and electrical phenomena. The limitation and quenching behavior of a resistive SCFCL assembly was investigated for overcurrents up to 67 kArms (Vo = 1 kVrms). Simulation results were compared to overcurrent experimental tests. A good agreement between simulations and tests has been found in the present work. Moreover, the results of the developed model were also compared with finite element results reported in the literature.

W.T.B. de Sousa; A. Polasek; R. Dias; C.F.T. Matt; R. de Andrade Jr.

2014-01-01T23:59:59.000Z

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61

Finite-element modelling of YBCO fault current limiter with temperature dependent  

Science Journals Connector (OSTI)

In this paper, we present a numerical model which takes into account both the thermal and the electromagnetic aspects of the over-critical current regime for high-temperature superconducting (HTS) materials. The electromagnetic and thermal equations have been implemented in finite-element method (FEM) software in order to obtain a novel model for investigating the behaviour of the materials when the current exceeds Ic and the superconductor material goes to the normal state. The thermal dependence of the electrical parameters, such as the critical current density Jc, has been introduced. This model has been used to analyse the behaviour of strip lines of a YBCO/Au fault current limiter (FCL) on a sapphire substrate. Simulations with currents exceeding Ic have been performed, showing that the current limitation phase can be correctly reproduced. Such a model can be used to study the influence of the geometry on the performance of the FCL. It can replace experiments with currents exceeding Ic which may damage or destroy HTS samples and devices.

J Duron; F Grilli; L Antognazza; M Decroux; B Dutoit; Ø Fischer

2007-01-01T23:59:59.000Z

62

A YBCO-coated conductor for a fault current limiter: architecture influences and optical  

Science Journals Connector (OSTI)

YBaCuO-coated conductors (CC) are particularly interesting for the electric grid, especially for superconducting (SC) fault current limiters (FCL). This innovative device should play an important part in the future electric energy landscape. New network diagrams are indeed imagined with DC buses. The SC FCL would solve the delicate problem of DC fault currents. We have studied several YBaCuO-coated conductors with different architectures. A test bench for optical measurements has been developed to study the bubble development during limitation or over-current operation. The observations give useful information about the quench initiation and its propagation. The images were recorded every 0.2 ms (or less). Preliminary experiments have been carried out using a copper strip. Several operating temperatures have been investigated and important differences have been observed in some cases. The different YBaCuO CC studied show very different behaviours. Bubbles appear under the shape of strips across the tape or show a homogeneous behaviour. These behaviours are correlated by electrical measurements.

N T Nguyen; P Tixador

2010-01-01T23:59:59.000Z

63

Quench current degradation in superconducting coil for 6.6 kV/2 fault current limiter  

SciTech Connect

A 6.6 kV/2 kA class fault current limiter that consists of non-inductive superconducting windings was developed and tested. The limiter can deliver continuous power at 2 kArms and limit fault current of more than 20 kA to 4 kA in 6 kV. The limiter recovers to the superconducting state within a few seconds and can perform a fault current limiting operation in 60 seconds after the last limiting operation. After high-voltage operation, however, the quench current of the limiter dropped significantly. This quench current degradation is related to the coil bobbin strain due to helium pressure raised by large ohmic heating in quenching. The degradation is a fatal problem for a fault current limiter if the quench current falls below the operating current because the limiter cannot revert to the normal operation. High Young`s modulus bobbin is effective to remove the coil degradation. They have obtained a fault current limiter without any degradation after repeated limiting operations.

Tasaki, K.; Yazawa, T.; Yoneda, E.S.; Nomura, S.; Maeda, H. [Toshiba Corp., Kawasaki (Japan). Research and Development Center] [Toshiba Corp., Kawasaki (Japan). Research and Development Center; Ohkuma, T.; Nakade, M.; Hara, T. [Tokyo Electric Power Co., Yokohama (Japan). Power Engineering R and D Center] [Tokyo Electric Power Co., Yokohama (Japan). Power Engineering R and D Center

1996-07-01T23:59:59.000Z

64

14 kV single-phase superconducting fault current limiter based on YBCO films  

Science Journals Connector (OSTI)

We present the fabrication and short circuit test results of a 14 kV single-phase resistive superconducting fault current limiter (SFCL) based on \\{YBa2Cu3O7\\} (YBCO) films. Individual components were processed using the 4? YBCO films and have the rated voltage and current of 600 V and 35 A at 77 K, respectively. Twenty four components, eight components in series and three lines in parallel, make a module having the rated voltage and current of 4.8 kV and 105 A, respectively. Three modules were assembled in series to produce the SFCL working at 77 K, a 14 kV single-phase machine for the 22.9 kV Y–Y grid. short circuit tests were successfully conducted in an accredited test facility with the maximum fault currents up to 14.1 kAP. All components quenched together upon faults and shared the rated voltage evenly without any supplementary device between the modules. This proves that the SFCL based on YBCO films may not only work reliably at 22.9 kV, but also provide technical feasibility for higher voltage application including the transmission grids.

J. Sim; K.B. Park; H.R. Kim; J.S. Kang; B.W. Lee; H.M. Kim; I.S. Oh; O.B. Hyun

2007-01-01T23:59:59.000Z

65

Ca intercalated bilayer graphene as a thinnest limit of superconducting C6Ca  

Science Journals Connector (OSTI)

...superconductivity and rechargeable batteries. It is thus quite challenging...intercalated bilayer graphene, and to investigate...useful in fabricating graphene-based nanodevices...devices, ultrathin battery and microchemical catalysis...Thus, intercalated graphene provides a promising...

Kohei Kanetani; Katsuaki Sugawara; Takafumi Sato; Ryota Shimizu; Katsuya Iwaya; Taro Hitosugi; Takashi Takahashi

2012-01-01T23:59:59.000Z

66

500 V/200 A fault current limiter modules made of large-area MOD-YBa2Cu3O7 thin films with high-resistivity Au–Ag alloy shunt layers  

Science Journals Connector (OSTI)

We developed 500 Vrms/ 200 Arms superconducting thin-film fault current limiter (FCL) modules that can withstand high electric fields (E>30 Vrms cm?1) by using large-area YBa2Cu3O7 (YBCO) thin films with high-resistivity Au–Ag alloy shunt layers. Au–Ag alloy films about 60 nm thick were sputter-deposited on YBCO/CeO2/sapphire films (2.7 cm ? 20 cm) prepared using a fluorine-free MOD method. Each 20 cm long Au–Ag/YBCO film was then divided into three segments (each ~5.7 cm long) by four Ag electrodes deposited on the Au–Ag layer, resulting in an effective length of 17 cm. The 500 V/200 A FCL modules were then fabricated by first connecting two of the segmented films in parallel using Ag-sheathed Bi-2223 superconducting tapes and then connecting in parallel an external resistor and a capacitor for each segment to protect the Au–Ag/YBCO film from hot spots. Switching tests using a short-circuit generator revealed that all the modules carried a superconducting ac current of ?237 Arms and that modules prepared with YBCO films having a relatively homogeneous critical current Ic distribution successfully withstood ?515 Vrms for five cycles without any damage. These results demonstrate that (a) the FCL modules fabricated here successfully achieved the rated current of 200 Arms and rated voltage of 500 Vrms and (b) total area of the YBCO films on sapphire substrates required for the 500 V/200 A (100 kV A) module was less than one-third that for conventional thin-film FCL modules that use gold shunt layers, leading to the significantly reduced cost of thin-film FCLs. Film damage due to hot spots depended on the difference in Ic between the two parallel-connected films and on the inhomogeneity of the Ic distribution in the film, and is most probably due to nonlinear current flows at the moment of quenching that cause local overheating.

H Yamasaki; K Arai; K Kaiho; Y Nakagawa; M Sohma; W Kondo; I Yamaguchi; H Matsui; T Kumagai; N Natori; N Higuchi

2009-01-01T23:59:59.000Z

67

Assessment on the influence of resistive superconducting fault current limiter in VSC-HVDC system  

Science Journals Connector (OSTI)

Abstract Due to fewer risk of commutation failures, harmonic occurrences and reactive power consumptions, Voltage Source Converter (VSC) based HVDC system is known as the optimum solution of HVDC power system for the future power grid. However, the absence of suitable fault protection devices for HVDC system hinders the efficient VSC-HVDC power grid design. In order to enhance the reliability of the VSC-HVDC power grid against the fault current problems, the application of resistive Superconducting Fault Current Limiters (SFCLs) could be considered. Also, \\{SFCLs\\} could be applied to the VSC-HVDC system with integrated AC Power Systems in order to enhance the transient response and the robustness of the system. In this paper, in order to evaluate the role of \\{SFCLs\\} in VSC-HVDC systems and to determine the suitable position of \\{SFCLs\\} in VSC-HVDC power systems integrated with AC power System, a simulation model based on Korea Jeju-Haenam HVDC power system was designed in Matlab Simulink/SimPowerSystems. This designed model was composed of VSC-HVDC system connected with an AC microgrid. Utilizing the designed VSC-HVDC systems, the feasible locations of resistive \\{SFCLs\\} were evaluated when DC line-to-line, DC line-to-ground and three phase AC faults were occurred. Consequently, it was found that the simulation model was effective to evaluate the positive effects of resistive \\{SFCLs\\} for the effective suppression of fault currents in VSC-HVDC systems as well as in integrated AC Systems. Finally, the optimum locations of \\{SFCLs\\} in VSC-HVDC transmission systems were suggested based on the simulation results.

Jong-Geon Lee; Umer Amir Khan; Jae-Sang Hwang; Jae-Kyu Seong; Woo-Ju Shin; Byung-Bae Park; Bang-Wook Lee

2014-01-01T23:59:59.000Z

68

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

E-Print Network (OSTI)

H, ($"'"1 (with d the spatial dimension of the network) as the universal limiting behavior of H,*2(T) as T T,u, H 2 0. We demon- strate with several examples that this is not true for networks with low point-group symmetry. We then propose that the above... and infinite superconducting networks; in particular, for infinite periodic networks, they proposed the formula (7.) dH (bulk) (7-) (1) 2 tr&'(T) as the universal behavior of H, 2(T) in the continuum lim- it, i.e., as T T,o and H, 2 0. In the above, d...

Hu, Chia-Ren.

1987-01-01T23:59:59.000Z

69

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

SciTech Connect

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

Muljadi, E.; Gevorgian, V.

2011-05-01T23:59:59.000Z

70

Proposed flux-based optimization method for determination of minimum superconductor material in shield-type superconducting fault current limiters  

Science Journals Connector (OSTI)

Distributed power generation and an ever growing load demand have caused the current level of fault to exceed the nominal rating of power system devices, and fault current limiters are needed even more. The Superconducting Fault Current Limiter, SFCL, forms an efficient category of current limiters. The superconductor part in \\{SFCLs\\} is the most costly part of the device, and minimizing its volume, while maintaining the required characteristics of the device, would be very beneficial. In this work, using a Simulated Annealing optimization algorithm, a method has been proposed to determine minimum required bulk superconductor material in inductive shield-type SFCL structures. The flux linkage balance, generated by the superconductor bulk and copper winding (being the base of the optimization process), has been formulated versus dimensions. The optimum dimensions of the bulk superconductor in a model SFCL, having a limitation current of 3 A , are determined using the proposed algorithm. A prototype has been fabricated using determined dimensions, and is tested in an experimental circuit by applying different types of faults. These experimental results demonstrated satisfactory limiting characteristics of the fabricated SFCL. The optimum volume of the bulk superconductor material needed for fabrication of larger scale \\{SFCLs\\} has been calculated and compared with the volume of superconductors employed in worldwide SFCL projects.

A. Hekmati; M. Vakilian; M. Fardmanesh

2012-01-01T23:59:59.000Z

71

Application of a combined superconducting fault current limiter and STATCOM to enhancement of power system transient stability  

Science Journals Connector (OSTI)

Abstract Stable and reliable operation of the power system network is dependent on the dynamic equilibrium between energy production and power demand under large disturbance such as short circuit or important line tripping. This paper investigates the use of combined model based superconducting fault current limiter (SFCL) and shunt FACTS Controller (STATCOM) for assessing the transient stability of a power system considering the automatic voltage regulator. The combined model located at a specified branch based on voltage stability index using continuation power flow. The main role of the proposed combined model is to achieve simultaneously a flexible control of reactive power using STATCOM Controller and to reduce fault current using superconducting technology based SFCL. The proposed combined model has been successfully adapted within the transient stability program and applied to enhance the transient power system stability of the WSCC9-Bus system. Critical clearing time (CCT) has been used as an index to evaluate and validate the contribution of the proposed coordinated Controller. Simulation results confirm the effectiveness and perspective of this combined Controller to enhance the dynamic power system performances.

Belkacem Mahdad; K. Srairi

2013-01-01T23:59:59.000Z

72

A Study on a High-Tc Superconducting Fault Current Limiter  

Science Journals Connector (OSTI)

The application of a high-Tc superconductor with a high critical current density (Jc) to a fault current limiter has been investigated. When the superconductor changes ... , it has a resistance which can limit fault

Tatsuya Hayashi; Teijiro Mori; Yuuichi Wada…

1992-01-01T23:59:59.000Z

73

Experimental testing and modelling of a resistive type superconducting fault current limiter using MgB2 wire  

Science Journals Connector (OSTI)

A prototype resistive superconducting fault current limiter (SFCL) was developed using single-strand round magnesium diboride (MgB2) wire. The MgB2 wire was wound with an interleaved arrangement to minimize coil inductance and provide adequate inter-turn voltage withstand capability. The temperature profile from 30 to 40 K and frequency profile from 10 to 100 Hz at 25 K were tested and reported. The quench properties of the prototype coil were tested using a high current test circuit. The fault current was limited by the prototype coil within the first quarter-cycle. The prototype coil demonstrated reliable and repeatable current limiting properties and was able to withstand a potential peak current of 372 A for one second without any degradation of performance. A three-strand SFCL coil was investigated and demonstrated scaled-up current capacity. An analytical model to predict the behaviour of the prototype single-strand SFCL coil was developed using an adiabatic boundary condition on the outer surface of the wire. The predicted fault current using the analytical model showed very good correlation with the experimental test results. The analytical model and a finite element thermal model were used to predict the temperature rise of the wire during a fault.

A C Smith; A Oliver; X Pei; M Husband; M Rindfleisch

2012-01-01T23:59:59.000Z

74

Extending the range of applicability of HTS cylinders in inductive superconducting fault current limiters  

Science Journals Connector (OSTI)

In the numerical routine used to estimate the temperature of the weak zones (channels) an error was introduced. Once the error is eliminated, the improvement in the thermal refrigeration of the inductive fault current limiters with artificial weak zones still remains but its importance is reduced; a channelled cylinder can refrigerate faster than a non-channelled one, as heat is removed also by conduction to the cold parts, but under a current fault the temperature of the weak zones is very much above those displayed in figure 3(b) and figure 4 (140 K is our best result, Tc being 105 K). As a consequence, the channelled cylinder needs about 9 s to get the critical temperature for the nominal current, whereas the non-channelled cylinder requires more than 15 s (both refrigerated by liquid nitrogen). Although appreciable, this improvement is still far from the usually required recovery time, which is about 1 s. This design could be more appropriate for a fault current limiter working in a slightly lower power grid or in a gaseous atmosphere, where the channelled sample is definitely much better than the non-channelled cylinder. To be competitive when operating in liquid nitrogen some additional mechanism should be implemented to avoid the excessive heating of the weak zones.

M R Osorio; J A Lorenzo; J A Veira; F Vidal

2008-01-01T23:59:59.000Z

75

Influence of fault type on the optimal location of superconducting fault current limiter in electrical power grid  

Science Journals Connector (OSTI)

Abstract This paper presents a novel approach to determine the optimal location of a resistive superconducting fault current limiter (SFCL) to improve the transient stability of an electric power grid (EPG). The presented method use the angular separation of the rotors of synchronous machines present in the power system to select the optimal location of SFCL. The selection of this optimal location is coordinated with the corresponding optimal resistive value to improve transient stability in case of short-circuit fault. To obtain a global study on the optimal placement of SFCL in case of fault, various types of short-circuits are considered (single phase grounded fault, two phases grounded fault, etc.). To evaluate the effectiveness of the proposed method, the IEEE benchmarked four-machine two-area test system is used to carry out several case studies. It is shown that the optimal location of SFCL as well as its optimal resistance value are not the same for each fault studied. A global analysis of EPG stability is presented in the paper to select only one location of the SFCL in the EPG. Results show that the optimal location of SFCL combined with its optimal resistive value reduces the angular separation of the rotors that improves effectively the stability of the EPG for any type of short-circuit.

G. Didier; J. Lévêque

2014-01-01T23:59:59.000Z

76

Fault current limiter with shield and adjacent cores  

DOE Patents (OSTI)

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

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

2013-10-22T23:59:59.000Z

77

X-Ray Storage Luminescence of BaFCl:Eu2+ Single Crystals Nomadics, Inc., 1024 South InnoVation Way, Stillwater, Oklahoma 74074  

E-Print Network (OSTI)

X-Ray Storage Luminescence of BaFCl:Eu2+ Single Crystals Wei Chen* Nomadics, Inc., 1024 South InnoVed: January 18, 2005; In Final Form: March 22, 2005 Temperature behaviors of X-ray luminescence (XL might not be oxidized to Eu3+ upon X-ray or -irradiation. Instead, the color centers, Cl excitons

Chen, Reuven

78

Superconductivity Program Overview High-Temperature Superconductivity  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

SuperconducTiviTy program haS Three FocuS areaS: SuperconducTiviTy program haS Three FocuS areaS: SuperconducTiviTy applicaTionS Developing HTS-based electric power equipment such as transmission and distribution cables and fault current limiters Second-generaTion Wire developmenT Developing high-performance, low-cost, second- generation HTS wire at long lengths STraTegic reSearch Supporting fundamental research activities to better understand relationships between the microstructure of HTS materials and their ability to carry large electric currents over long lengths Superconductivity Program Overview High-Temperature Superconductivity for Electric Systems Office of Electricity Delivery and Energy Reliability www.oe.energy.gov Office of Electricity Delivery and Energy Reliability, OE-1 U.S. Department of Energy - 1000 Independence Avenue, SW - Washington, DC 20585

79

Superconductivity for Electric Systems Annual Peer Review Arlington, VA July 25-27, 2006Superconductivity for Electric Systems Annual Peer Review Arlington, VA July 25-27, 2006 Understanding and Pushing the Limits  

E-Print Network (OSTI)

Superconductivity for Electric Systems Annual Peer Review Arlington, VA July 25-27, 2006Superconductivity for Electric Systems Annual Peer Review Arlington, VA July 25-27, 2006 Understanding and Pushing pinning " #12;Superconductivity for Electric Systems Annual Peer Review Arlington, VA July 25-27, 2006

80

Cost reduction of distribution network protection in presence of distributed generation using optimized fault current limiter allocation  

Science Journals Connector (OSTI)

Using Solid State Fault Current Limiters (SSFCLs) has been proposed as a potential cost-efficient candidate to minimize the effect of exposing Distributed Generation (DG) to the distribution system. Genetic Algorithm (GA) is employed to find the optimum number, location and size of \\{FCLs\\} to be used in the network. The numerical and simulation results show the efficiency of proposed GA-based FCL allocation and sizing method in terms of minimizing the cost of distribution protection system. The prices of \\{FCLs\\} are estimated using real market prices and simulations are performed in four cases assuming prices more than the estimated one, less than estimated price and equal to the real estimated cost for FCL. Numerical results show that FCL price highly affects the optimum choices for \\{FCLs\\} and the price imposed by using FCLs.

Sayyed Ali Akbar Shahriari; Ali Yazdian Varjani; Mahmood Reza Haghifam

2012-01-01T23:59:59.000Z

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


81

Development of a 6.6kV/1.5kA-Class Superconductive Fault Current Limiter  

Science Journals Connector (OSTI)

The authors developed an AC current limiter, possessing extremely fine filaments and a high-resistance matrix, and noninductively wound with a single secondary strand. This device successfully limited a 54.5 k...

T. Hara; T. Okuma; M. Nakade; T. Yamamoto; D. Ito…

1993-01-01T23:59:59.000Z

82

Hybrid model of quench propagation in coated conductors for fault current limiters  

Science Journals Connector (OSTI)

We developed a hybrid model of the quench propagation in coated conductors in the current limitation condition. This model combines the finite element method, to study the thermal behaviour of the coated conductors, and analytical calculation of the heat dissipation. We demonstrate that the evaluation of the heat dissipation can be conducted on a larger mesh than the FEM thermal problem. The results obtained with this model are in very good agreement with experiments, without the need of using free parameters for adjustment. Parametric studies are then conducted to evaluate the influence of both the substrate thickness and the layer interface thermal properties on the transition propagation behaviour. 3D simulations of a thin superconducting line placed on a wider substrate are also presented. Significant transverse heat propagation is observed in spite of the low thermal conductivity of the substrate, though this has little to no influence on the transition propagation along the line. These results are discussed in the context of FCL design.

Arnaud Badel; Louis Antognazza; Mathieu Therasse; Markus Abplanalp; C Schacherer; Michel Decroux

2012-01-01T23:59:59.000Z

83

Limiter  

DOE Patents (OSTI)

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

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

1984-10-19T23:59:59.000Z

84

Limiter  

DOE Patents (OSTI)

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

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

1986-01-01T23:59:59.000Z

85

Detection limits of high temperature superconducting materials on various substrates by energy dispersive X-ray fluorescence and proton induced X-ray emission methods  

Science Journals Connector (OSTI)

Application of energy dispersive X-ray fluorescence (EDXRF) and proton induced X-ray emission (PIXE) methods has been demonstrated for determining the elemental composition of thin film superconducting materia...

M Lal; H N Bajpai; D Joseph; R K Choudhury

1990-04-01T23:59:59.000Z

86

Superconducting Cable  

DOE Patents (OSTI)

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.

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

87

Superconducting Cable  

DOE Patents (OSTI)

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.

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

88

National High Magnetic Field Laboratory - Applied Superconductivity...  

NLE Websites -- All DOE Office Websites (Extended Search)

viable present materials for superconducting application to electric power transmission lines, fault current limiters, transformers, electromagnets and motors. UW-Madison has...

89

National High Magnetic Field Laboratory - Applied Superconductivity...  

NLE Websites -- All DOE Office Websites (Extended Search)

viable present materials for superconducting application to electric power transmission lines, fault current limiters, transformers, electromagnets and motors. Coated Conductors We...

90

Fault current limiter using a series impedance combined with bus sectionalizing circuit breaker  

Science Journals Connector (OSTI)

The necessity and procedure for application of series fault current limiter (FCL) composed to bus sectionalizing in power network of IRAN have been discussed. In this regard, all of the high voltage substations in the power network of IRAN were evaluated in point of view of the fault current amplitude. The short circuit analysis of the power network was done based on the actual and future network specifications which have been designed and published by Iran Generation Transmission & Distribution Company in 2005. The overall results of this analysis and the detail data of using FCL together bus sectionalizing for two of the most important high voltage substations of Iran are presented. This method allows decreasing of 27% in fault current amplitude. The economical observation shows this method can be profitable if high voltage substation contains more than four feeders.

Hamid Javadi

2011-01-01T23:59:59.000Z

91

Superconducting magnet  

DOE Patents (OSTI)

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.

Satti, John A. (Naperville, IL)

1980-01-01T23:59:59.000Z

92

Secrets of superconductivity revealed  

NLE Websites -- All DOE Office Websites (Extended Search)

Secrets of superconductivity revealed Secrets of superconductivity revealed Secrets of superconductivity revealed The superconducting material Cerium-Colbalt-Indium5 reveals new secrets about how superconductivity and magnetism can be related. January 3, 2014 Simon Gerber, first author of the publication on the superconducting properties of CeCoIn5 at the Morpheus instrument of the Spallation Neutron Source SINQ in Switzerland. (Photo: Paul Scherrer Institute/Markus Fischer) Simon Gerber, first author of the publication on the superconducting properties of CeCoIn5 at the Morpheus instrument of the Spallation Neutron Source SINQ in Switzerland. (Photo: Paul Scherrer Institute/Markus Fischer) "Superconductivity continues to give new surprises. As its secrets are revealed, we learn more about the quantum world of electrons and can begin

93

Secrets of superconductivity revealed  

NLE Websites -- All DOE Office Websites (Extended Search)

Secrets of superconductivity revealed Secrets of superconductivity revealed Secrets of superconductivity revealed The superconducting material Cerium-Colbalt-Indium5 reveals new secrets about how superconductivity and magnetism can be related. January 3, 2014 Simon Gerber, first author of the publication on the superconducting properties of CeCoIn5 at the Morpheus instrument of the Spallation Neutron Source SINQ in Switzerland. (Photo: Paul Scherrer Institute/Markus Fischer) Simon Gerber, first author of the publication on the superconducting properties of CeCoIn5 at the Morpheus instrument of the Spallation Neutron Source SINQ in Switzerland. (Photo: Paul Scherrer Institute/Markus Fischer) "Superconductivity continues to give new surprises. As its secrets are revealed, we learn more about the quantum world of electrons and can begin

94

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

DOE Patents (OSTI)

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.

Norem, James H.; Pellin, Michael J.

2013-06-11T23:59:59.000Z

95

Prototype Fault Current Limiter Using Transformer and a Modular Device of YBCO Coated Conductor  

Science Journals Connector (OSTI)

A superconducting fault current limiter (SCFL) consisted of a transformer with ... secondary winding short-circuited by a modular superconducting limiter device with 16 elements connected in series ... a 0.125 ? ...

C. A. Baldan; J. S. Lamas; A. A. Bernardes…

2013-04-01T23:59:59.000Z

96

Onset of surface superconductivity  

SciTech Connect

We examine the onset of superconductivity in the surface region of a metal. Surface effects are particularly important in systems with a short bulk coherence length {xi}{sub 0}. We show that, to the accuracy of the calculation, the surface transition temperature {ital T}{sub {ital c}{ital S}} equals the bulk transition temperature {ital T}{sub {ital c}{ital B}} if the electron-electron interaction is of the standard BCS form, i.e., a single attractive square well, extending up to some critical energy {omega}{sub 0} much smaller than the Fermi energy {var epsilon}{sub {ital F}}. If one takes into account, in addition, the repulsive part of the interaction extending beyond {omega}{sub 0} up to energies of order {var epsilon}{sub {ital F}}, then one may have {ital T}{sub {ital c}{ital S}}{gt}{ital T}{sub {ital c}{ital B}} in certain cases, although, due to restrictions imposed on the parameter values by various physical conditions, the relative increase of {ital T}{sub {ital c}} is very small, typically 10{sup {minus}3}, at least in the weak coupling limit. However, we also find a considerable gap enhancement, of order 20%, near the surface which could be of interest for critical-current measurements. Therefore we suggest an experimental reexamination of systems with short {xi}{sub 0}, i.e., superconducting degenerate semiconductors and the new high-{ital T}{sub {ital c}} oxides in confined geometries where the surface-to-volume ratio is non-negligible.

Giamarchi, T.; Beal-Monod, M.T. (Laboratoire de Physique des Solides, Universite Paris-Sud 91405 Orsay, (France)); Valls, O.T. (Laboratoire de Physique des Solides, Universite Paris-Sud, 91405 Orsay, (France) Center for the Science and Application of Superconductivity, School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (USA))

1990-06-01T23:59:59.000Z

97

Superconducting VAR control  

DOE Patents (OSTI)

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

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

1982-01-01T23:59:59.000Z

98

Superconducting Radiofrequency (SRF) Accelerator Cavities  

SciTech Connect

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

Reece, Charlie

2013-05-03T23:59:59.000Z

99

Superconducting Radiofrequency (SRF) Accelerator Cavities  

ScienceCinema (OSTI)

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

Reece, Charlie

2014-05-22T23:59:59.000Z

100

Optimal power flow considering fault current level constraints and fault current limiters  

Science Journals Connector (OSTI)

Abstract The aim of this paper is to present a novel method to dispatch the active generation power properly in the power system while incorporating fault current levels as constraints for the optimization problem. Due to the limited capacity of protective devices such as circuit breakers, allocating active power without considering fault current levels can probably lead to fault currents exceeding the rating of these devices. Hence restricting the fault current levels to an allowable amount while minimizing a specified objective function seems to be necessary. In a number of cases even the appropriate allocation of active power is not able to reduce the fault current levels to the permitted amount therefore using fault current limiters (FCL) is unavoidable. In this paper also a planning scheme is presented for the location and sizing of fault current limiters and the effect of fault current limiters on the objective functions is investigated.

Amirhossein Khazali; Mohsen Kalantar

2014-01-01T23:59:59.000Z

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


101

6.763 Applied Superconductivity, Fall 2001  

E-Print Network (OSTI)

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

Orlando, Terry P.

102

Superconducting active impedance converter  

DOE Patents (OSTI)

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.

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

1993-11-16T23:59:59.000Z

103

Superconducting active impedance converter  

DOE Patents (OSTI)

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.

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

1993-01-01T23:59:59.000Z

104

Secrets of superconductivity revealed  

NLE Websites -- All DOE Office Websites (Extended Search)

material Cerium-Colbalt-Indium5 reveals new secrets about how superconductivity and magnetism can be related. January 3, 2014 Simon Gerber, first author of the publication on the...

105

Superconducting thermoelectric generator  

DOE Patents (OSTI)

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.

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

1996-01-01T23:59:59.000Z

106

Superconducting thermoelectric generator  

DOE Patents (OSTI)

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.

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

1998-01-01T23:59:59.000Z

107

Superconducting thermoelectric generator  

DOE Patents (OSTI)

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.

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

1998-05-05T23:59:59.000Z

108

Alexei Abrikosov and Superconductivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Alexei Abrikosov and Superconductivity Alexei Abrikosov and Superconductivity Resources with Additional Information · Publications at ANL Alexei A. Abrikosov of the U.S. Department of Energy's Argonne National Laboratory (ANL) is a recipient of the 2003 Nobel Prize in Physics for his research in the area of superconductivity. Alexei Abrikosov Courtesy Argonne National Laboratory "Abrikosov's research [at ANL] centers on condensed-matter physics (the structure and behavior of solids and liquids), and concentrates on superconductivity, the ability of some materials to carry electrical current without resistance. He was the first to propose the concept of "type-II superconductors" in 1952 and constructed the theory of their magnetic properties, known as the Abrikosov vortex lattice.

109

Supertubes and Superconducting Membranes  

SciTech Connect

We show the equivalence between configurations that arise from string theory of type IIA, called supertubes, and superconducting membranes at the bosonic level. We find equilibrium and oscillating configurations for a tubular membrane carrying a current along its axis.

Cordero, Ruben; Miguel-Pilar, Zelin [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del IPN, Edificio 9, Unidad Profesional 'Adolfo Lopez Mateos', Zacatenco, 07738 Mexico D.F. (Mexico)

2007-02-09T23:59:59.000Z

110

Superconducting transmission line particle detector  

DOE Patents (OSTI)

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.

Gray, K.E.

1988-07-28T23:59:59.000Z

111

Superconducting transmission line particle detector  

DOE Patents (OSTI)

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.

Gray, Kenneth E. (Naperville, IL)

1989-01-01T23:59:59.000Z

112

Progress in Superconducting Metamaterials  

E-Print Network (OSTI)

We review progress in the development and applications of superconducting metamaterials. The review is organized in terms of several distinct advantages and unique properties brought to the metamaterials field by superconductivity. These include the low-loss nature of the meta-atoms, their compact structure, their extraordinary degree of nonlinearity and tunability, magnetic flux quantization and the Josephson effect, quantum effects in which photons interact with quantized energy levels in the meta-atom, as well as strong diamagnetism.

Philipp Jung; Alexey V. Ustinov; Steven M. Anlage

2014-03-25T23:59:59.000Z

113

Simulation and Analysis of Superconducting Traveling-Wave Parametric Amplifiers  

E-Print Network (OSTI)

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.

Saptarshi Chaudhuri; Jiansong Gao; Kent Irwin

2015-01-11T23:59:59.000Z

114

Superconducting ohmic heating solenoid concept for ISX-C  

SciTech Connect

The employment of a superconducting ohmic heating solenoid is presented for ISX-C based on currently available superconducting technology. The magnet is designed to be cryostable and to generate the required flux swing of 4.5 V/s while simultaneously meeting the limitations imposed by available space and structural interfacing to the torroidal coils. A novel spliceless pancake winding scheme is proposed which offers excellent cooling and completely supports the cable conductor throughout the winding.

Shen, S.S.; Brown, R.L.; Gray, W.H.; Lubell, M.S.

1981-01-01T23:59:59.000Z

115

7 Superconductivity March 12, 2008  

E-Print Network (OSTI)

to measure. Current could be left flowing round a superconducting loop for several months without any and copper, do not seem to be superconducting, nor do the elements in Group IIA, such as calcium, but many

Thouless, David

116

Limited Lawn & Limited Commercial  

E-Print Network (OSTI)

Limited Lawn & Ornamental Limited Commercial Landscape Maintenance Review and Exams Limited for Commercial Landscape Maintenance Application: http://www.flaes.org/ pdf/lndspckt.pdf Limited Certification.floridatermitehelp.org or request by phone at 850-921-4177. Limited Lawn & Ornamental/Limited Commercial Landscape Maintenance

Watson, Craig A.

117

Limited Lawn & Limited Commercial  

E-Print Network (OSTI)

Limited Lawn & Ornamental Limited Commercial Landscape Maintenance Review and Exams Limited-921-4177. Limited Lawn & Ornamental/Limited Commercial Landscape Maintenance: Ornamental and Turf Pest Control (SM 7&O/Structural only). See web locations below for applications. Limited Certification for Commercial Landscape

Jawitz, James W.

118

Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

3 - 6/13/06 3 - 6/13/06 Superconducting Magnet Division S&T Committee Program Review June 22-23, 2006 Conference Room A, Bldg. 725, BNL DRAFT AGENDA Thursday, June 22 0830 Executive Session to address the charge S. Aronson (25 min) 0855 Welcome S. Aronson (5 min) 0900 Superconducting Magnet Division Status & M. Harrison (45 + 15 min) Issues - mission statement, core competencies, themes, program, problems, etc. 1000 Themes - Nb3Sn, HTS, Direct wind, Accelerator integration, P. Wanderer (20 + 10 min) rapid cycling Core Competencies 1030 Superconducting Materials A. Ghosh (20 + 5 min) 1055 Break 1110 Magnetic Design R. Gupta (20 + 5 min) 1135 Magnet Construction M. Anerella (20 + 5 min) 1200 Magnet Testing G. Ganetis (20 + 5 min)

119

LANL: Superconductivity Technology Center  

NLE Websites -- All DOE Office Websites (Extended Search)

Sitemap | Lab Home | Phone Sitemap | Lab Home | Phone ABOUT LANL ContactsPhonebookPolicy CenterOrganizationMapsJobs Emergency NEWS LIBRARY JOBS Search Materials Physics & Applications: STC STC Home OUR FOCUS HTS Physics HTS Materials Development HTS Materials Processing Power Applications Electronic Materials FUTURE APPLICATIONS Biomedical Developments Magnetic Levitation Train MHD Ship CONTACTS Center Leader Ken Marken Program Administrator Brenda Espinoza Center Office Location: TA-03, Bdg. 0032, Rm. 141 Exploring technology at STC Superconductivity Technology Center (STC) The Superconductivity Technology Center (STC) coordinates a multidisciplinary program for research, development, and technology transfer in the area of high-temperature superconductivity. Our focus is on effective collaborations with American industry, universities, and other national laboratories to develop electric power and electronic device applications of high-temperature superconductors (HTS).

120

Large Superconducting Magnet Systems  

E-Print Network (OSTI)

The increase of energy in accelerators over the past decades has led to the design of superconducting magnets for both accelerators and the associated detectors. The use of Nb?Ti superconducting materials allows an increase in the dipole field by up to 10 T compared with the maximum field of 2 T in a conventional magnet. The field bending of the particles in the detectors and generated by the magnets can also be increased. New materials, such as Nb3Sn and high temperature superconductor (HTS) conductors, can open the way to higher fields, in the range 13–20 T. The latest generations of fusion machines producing hot plasma also use large superconducting magnet systems.

Védrine, P

2014-01-01T23:59:59.000Z

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


121

Superconductivity | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Highlights Research Highlights Superconductivity Neutron diffraction reveals semiconducting phase and contributes to new understanding of iron-based superconductors Contact: Huibo Cao New VULCAN tests of Japanese cable for US ITER's central magnet system (2012) Contact: Ke An ARCS maps collaborative magnetic spin behavior in iron telluride (2011) Published Work: "Unconventional Temperature Enhanced Magnetism in Fe1:1Te" Contact: Igor Zaliznyak Doug Scalapino discusses "common thread" linking unconventional superconducting materials (2011) Contact: Douglas Scalapino Materials Engineering Research at SNS Helps International Collaboration on Fusion Energy Scientists and engineers at ORNL are working with the ITER Organization and the Japanese Atomic Energy Agency to resolve issues with a critical

122

Langmuir vacuum and superconductivity  

SciTech Connect

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.

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

2012-06-15T23:59:59.000Z

123

Superconductivity of Zirconium Alloys  

Science Journals Connector (OSTI)

The superconducting transition temperatures of alloys between zirconium and VIIIth column elements are substantially higher than those of zirconium. The same is true for zirconium-gold alloys. This observation confirms a rule previously established about the height of transition temperatures.

B. T. Matthias and E. Corenzwit

1955-10-15T23:59:59.000Z

124

Superconducting Magnet Division  

E-Print Network (OSTI)

in the 400 kW end of RIA's Fragment Separator are subjected to several orders of magnitude more radiation an order of magnitude as compared to that for present superconducting accelerator magnets. An OPERA3d model://www.phy.anl.gov/ria/ http://www.orau.org/ria/ Figure: On this chart of the nuclides, black squares represent stable nuclei

Gupta, Ramesh

125

Superconducting thermoelectric generator  

DOE Patents (OSTI)

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.

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

1994-01-01T23:59:59.000Z

126

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

SciTech Connect

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.

Rogers, J.D. (comp.)

1982-02-01T23:59:59.000Z

127

AFRD - Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Magnets Superconducting Magnets Home Organization Diversity Safety Links Gallery/History Updated July 2008 Ever-stronger magnets (which must be cost-effective as well) are a key to building tomorrow's high-energy accelerators and upgrading today's. Our role— not only a leading R&D group but also the administrators of the multi-institutional National Conductor Development Program— to create both evolutionary improvements and paradigm shifts in the application of accelerator magnets, providing innovative technology that enables new science. Improvements in conductor, innovative structures to solve the challenges of high fields and brittle superconductors, and integration of computerized design and analysis tools are key. The performance requirements of modern accelerators continue to press the

128

Landscape of superconducting membranes  

E-Print Network (OSTI)

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.

Frederik Denef; Sean A. Hartnoll

2009-03-20T23:59:59.000Z

129

Supercurrent in superconducting graphene  

Science Journals Connector (OSTI)

The problem of supercurrent in superconducting graphene is revisited and the supercurrent is calculated within the mean-field model employing the two-component wave functions on a honeycomb lattice with pairing between different valleys in the Brillouin zone. We show that the supercurrent within the linear approximation in the order-parameter-phase gradient is always finite even if the doping level is exactly zero.

N. B. Kopnin and E. B. Sonin

2010-07-13T23:59:59.000Z

130

Superconducting magnet wire  

DOE Patents (OSTI)

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..

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

1986-01-01T23:59:59.000Z

131

Superconducting Topological Insulators  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Topological Insulators Print Superconducting Topological Insulators Print Three-dimensional topological insulators (TIs), discovered experimentally in 2007-2009 by a Princeton-ALS collaboration, are a promising platform for developing the next generation of electronics. Electrons within one nanometer of a TI's surface move at high speeds in a "light-like" fashion. The quantum interactions that generate these electronic states cause individual electrons to be spin polarized even at room temperature and to strongly resist scattering from defects, naturally achieving some of the most desirable traits for computing components and next-generation "spintronics" technologies. More recent angle-resolved photoemission spectroscopy (ARPES) studies performed at ALS Beamlines 10.0.1 and 12.0.1 by the same collaboration have paved a way for these novel material properties to be taken even further. Their studies showed that by doping the TI, bismuth selenide, with copper, it's possible to make the topologically ordered electrons superconducting, dropping electrical resistance in the surface states all the way to zero.

132

Superconducting Topological Insulators  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Topological Insulators Print Superconducting Topological Insulators Print Three-dimensional topological insulators (TIs), discovered experimentally in 2007-2009 by a Princeton-ALS collaboration, are a promising platform for developing the next generation of electronics. Electrons within one nanometer of a TI's surface move at high speeds in a "light-like" fashion. The quantum interactions that generate these electronic states cause individual electrons to be spin polarized even at room temperature and to strongly resist scattering from defects, naturally achieving some of the most desirable traits for computing components and next-generation "spintronics" technologies. More recent angle-resolved photoemission spectroscopy (ARPES) studies performed at ALS Beamlines 10.0.1 and 12.0.1 by the same collaboration have paved a way for these novel material properties to be taken even further. Their studies showed that by doping the TI, bismuth selenide, with copper, it's possible to make the topologically ordered electrons superconducting, dropping electrical resistance in the surface states all the way to zero.

133

Superconducting Topological Insulators  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Topological Insulators Print Superconducting Topological Insulators Print Three-dimensional topological insulators (TIs), discovered experimentally in 2007-2009 by a Princeton-ALS collaboration, are a promising platform for developing the next generation of electronics. Electrons within one nanometer of a TI's surface move at high speeds in a "light-like" fashion. The quantum interactions that generate these electronic states cause individual electrons to be spin polarized even at room temperature and to strongly resist scattering from defects, naturally achieving some of the most desirable traits for computing components and next-generation "spintronics" technologies. More recent angle-resolved photoemission spectroscopy (ARPES) studies performed at ALS Beamlines 10.0.1 and 12.0.1 by the same collaboration have paved a way for these novel material properties to be taken even further. Their studies showed that by doping the TI, bismuth selenide, with copper, it's possible to make the topologically ordered electrons superconducting, dropping electrical resistance in the surface states all the way to zero.

134

Superconducting VAR control. [Patent application  

DOE Patents (OSTI)

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.

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

1980-12-05T23:59:59.000Z

135

SciTech Connect: Superconductivity  

Office of Scientific and Technical Information (OSTI)

English Subject: Condensed Matter Physics, Superconductivity & Superfluidity(75) Word Cloud More Like This Full Text File size NAView Full Text View Full Text DOI: 10.2172...

136

Power System Feedback from High-Tc Superconductor Shielded Core Fault Current Limiter  

Science Journals Connector (OSTI)

The shielded core fault current limiter is attractive with high critical temperature superconductors. ... acts during normal operation as an ideally shorted current transformer; the secondary superconducting loop...

J. Gerhold

1998-01-01T23:59:59.000Z

137

Optimization of superconducting tiling pattern for superconducting bearings  

DOE Patents (OSTI)

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.

Hull, J.R.

1996-09-17T23:59:59.000Z

138

Optimization of superconducting tiling pattern for superconducting bearings  

DOE Patents (OSTI)

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.

Hull, John R. (Hinsdale, IL)

1996-01-01T23:59:59.000Z

139

Power superconducting power transmission cable  

DOE Patents (OSTI)

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.

Ashworth, Stephen P. (Cambridge, GB)

2003-01-01T23:59:59.000Z

140

Superconductivity and Magnetism: Materials Properties  

E-Print Network (OSTI)

#12;#12;Superconductivity and Magnetism: Materials Properties and Developments #12;Copyright 2003 and Magnetism: Materials Properties and Developments Extended abstracts of the 24th Risø International Symposium LABORATORY ROSKILDE, DENMARK #12;Risø International Symposium on Superconductivity and Magnetism: Material

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


141

Superconductivity Highlights | Neutron Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconductivity Superconductivity SHARE Superconductivity Highlights 1-6 of 6 Results Doug Scalapino discusses "common thread" linking unconventional superconducting materials December 01, 2012 - Douglas Scalapino was the inaugural speaker for a new joint lecture series sponsored by the Spallation Neutron Source and the Center for Nanophase Materials Sciences at Oak Ridge National Laboratory. New VULCAN tests of Japanese cable for US ITER's central magnet system February 01, 2012 - Neutron testing of the Japanese-made superconducting cable for the central solenoid (CS) magnetic system for US ITER begins next Tuesday, says Ke An, lead instrument scientist for the VULCAN Engineering Materials Diffractometer at the Spallation Neutron Source. ARCS maps collaborative magnetic spin behavior in iron telluride

142

DOE Superconductivity Program Stakeholders  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Air Force Research Laboratory Air Force Research Laboratory Air Liquide Air Products and Chemicals Inc. American Electric Power American Superconductor Argonne National Laboratory BOC Group Brookhaven National Laboratory Composite Technology Development Consolidated Edison Cryo-Industries of America Inc. Delta Star Inc. Directed Vapor Technologies Department of Defense Department of Homeland Security Electric Power Research Institute Entergy Florida State University Long Island Power Authority Los Alamos National Laboratory Metal Oxide Technologies Inc. Mipox International Corp. National Grid National Institute for Standards & Tech. National Renewable Energy Laboratory Nissan Electric Co. Ltd. Nexans nkt Cables Group Oak Ridge National Laboratory Oxford Superconducting Technology Pacific Gas and Electric

143

A worldwide overview of superconductivity development efforts for utility applications  

SciTech Connect

The progress and prospects for the application of high temperature superconductivity to the electric power sector has been the topic of an IEA Implementing Agreement begun in 1990. The present task members are: Canada, Denmark, Finland, Germany, Israel, Italy, Japan, the Netherlands, Norway, Sweden, Switzerland, Turkey, the United Kingdom, and the United States. As a result of the Implementing Agreement, work has been performed by the Operating Agent with the full participation of all of the member countries. This work has facilitated the exchange of information among experts in all member countries and is the basis for much of the information contained in this paper. This paper summarizes progress toward application of high temperature superconductivity to devices for use in the electric power sector such as: fault-current limiters, cables, superconducting magnetic energy Storage, rotating machinery, transformers, and flywheels incorporating magnetic bearings. Such devices are being designed, built and tested throughout the world.

Giese, R.F.

1996-04-01T23:59:59.000Z

144

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

SciTech Connect

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.

NONE

1996-03-01T23:59:59.000Z

145

Superconducting Magnet Technology for Future Hadron Colliders  

SciTech Connect

The application of superconducting magnets to large-scale particle accelerators was successfully demonstrated with the completion of the Tevatron at Fermilab in 1983. This machine, utilizing dipole magnets operating at 4.5 T, has been operating successfully for the past 12 years. This success was followed a few years later by HERA, an electron-proton collider that uses superconducting quadrupoles and dipoles of a design similar to those in the Tevatron. The next major project was the ill-fated SSC, which was cancelled in 1993. However, the SSC R&D effort did succeed in demonstrating the reliable operation of dipole magnets up to 6.6 T. The LHC, now under construction, pushes the ductile superconductor, NbTi, to its limit in dipoles designed to operate at fields of 8.6 T at 1.8 K. Several recent studies have addressed the issues involved in taking the next step beyond the LHC. The Division of Particles and Fields Workshop on Future Hadron Facilities in the U.S., held at Indiana U. in 1994, examined two possible facilities--a 2-TeV on 2-TeV collider and a 30-Tev on 30-Tev collider. The participants arrived at the following conclusions with regard to superconducting magnets: (1) Superconducting magnets are the enabling technology for high energy colliders. As such, the highest priority for the future of hadron facilities in the U.S. is the reassembly of a U.S. superconducting magnet R&D program. (2) emphasis on conductor development and new magnet designs; and (3) goals of such a program might be (a) the development of a 9-10 Tesla magnet based on NbTi technology; (b) the development of high quality quadrupoles with gradients in the range 250-300 T/m; and (c) initiation of R&D activities aimed at moving beyond the existing technology as appears to be required for the development of a magnet operating at 12-15 Tesla. In order to reach fields above 10 T, magnet designers must turn to new materials with higher critical fields than that of NbTi. Several candidate conductors exist; unfortunately, all of these new materials are brittle, and thus pose new challenges to the magnet designers. At the same time that the forces on the magnet windings are increasing due to the higher Lorentz force associated with the higher magnetic fields, the conductor tensile strain must be limited to less than about 0.5% to prevent damage to the brittle superconducting material. Also, coil fabrication methods must be changed. If the superconductor is in the reacted, or brittle, state, the coil winding procedure must be modified to prevent overstraining. If the alternative wind and react approach is used, new insulating materials must be used that can survive the high temperature reactions (650 to 800 C) necessary to form the superconducting compounds. The issues associated with high-field dipole magnets have been discussed at a number of workshops, including those at DESY in 1991 and LBL in 1992. These workshops were extremely useful in defining the problems and focusing the attention of both materials and magnet experts on high-field dipole magnets; however, since neither set of proceedings was published, the information is not readily available. More recently, a workshop was held in Erice, Italy, under the sponsorship of the Ettore Maiorana Center for Scientific Culture. This international workshop was attended by 20 scientists from Europe, Japan, and the U.S., and the summary of that work, which represents the most recent and thorough assessment of the status of high-field magnets for accelerator magnets, is presented.

Scanlan, R.M.; Barletta, W.A.; Dell'Orco, D.; McInturff, A.D.; Asner, A.; Collings, E.W.; Dahl, P.F.; Desportes, H.; Devred, A.; Garre, R.; Gregory, E.; Hassenzahl, W.; Lamm, M.; Larbalestier, D.; Leory, D.; McIntyre, P.; Miller, J.; Shintomi, T.; ten Kate, H.; Wipf, S.

1994-10-01T23:59:59.000Z

146

Superconductive tunnel junction integrated circuit  

SciTech Connect

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

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

1984-02-07T23:59:59.000Z

147

Development of superconducting magnet systems for HIFExperiments  

SciTech Connect

The U.S. Heavy Ion Fusion program is developing superconducting focusing quadrupoles for near-term experiments and future driver accelerators. Following the fabrication and testing of several models, a baseline quadrupole design was selected and further optimized. The first prototype of the optimized design achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, with measured field harmonics within 10 parts in 10{sup 4}. In parallel, a compact focusing doublet was fabricated and tested using two of the first-generation quadrupoles. After assembly in the cryostat, both magnets reached their conductor-limited quench current. Further optimization steps are currently underway to improve the performance of the magnet system and reduce its cost. They include the fabrication and testing of a new prototype quadrupole with reduced field errors as well as improvements of the cryostat design for the focusing doublet. The prototype units will be installed in the HCX beamline at LBNL, to perform accelerator physics experiments and gain operational experience. Successful results in the present phase will make superconducting magnets a viable option for the next generation of integrated beam experiments.

Sabbi, Gian Luca; Faltens, A.; Leitzke, A.; Seidl, P.; Lund, S.; Martovets ky, N.; Chiesa, L.; Gung, C.; Minervini, J.; Schultz, J.; Goodzeit, C.; Hwang, P.; Hinson, W.; Meinke, R.

2004-07-27T23:59:59.000Z

148

Superconducting magnetic energy storage  

SciTech Connect

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.

Hassenzahl, W.

1988-08-01T23:59:59.000Z

149

The LHC superconducting cavities  

E-Print Network (OSTI)

The LHC RF system, which must handle high intensity (0.5 A d.c.) beams, makes use of superconducting single-cell cavities, best suited to minimizing the effects of periodic transient beam loading. There will be eight cavities per beam, each capable of delivering 2 MV (5 MV/m accelerating field) at 400 MHz. The cavities themselves are now being manufactured by industry, using niobium-on-copper technology which gives full satisfaction at LEP. A cavity unit includes a helium tank (4.5 K operating temperature) built around a cavity cell, RF and HOM couplers and a mechanical tuner, all housed in a modular cryostat. Four-unit modules are ultimately foreseen for the LHC (two per beam), while at present a prototype version with two complete units is being extensively tested. In addition to a detailed description of the cavity and its ancillary equipment, the first test results of the prototype will be reported.

Boussard, Daniel; Häbel, E; Kindermann, H P; Losito, R; Marque, S; Rödel, V; Stirbet, M

1999-01-01T23:59:59.000Z

150

Information entropic superconducting microcooler  

Science Journals Connector (OSTI)

We consider a design for a cyclic microrefrigerator using a superconducting flux qubit. Adiabatic modulation of the flux combined with thermalization can be used to transfer energy from a lower temperature normal metal thin film resistor to another one at higher temperature. The frequency selectivity of photonic heat conduction is achieved by including the hot resistor as part of a high frequency LC resonator and the cold one as part of a low-frequency oscillator while keeping both circuits in the underdamped regime. We discuss the performance of the device in an experimentally realistic setting. This device illustrates the complementarity of information and thermodynamic entropy as the erasure of the quantum bit directly relates to the cooling of the resistor.

A. O. Niskanen; Y. Nakamura; J. P. Pekola

2007-11-29T23:59:59.000Z

151

Superconducting energy storage  

SciTech Connect

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.

Giese, R.F.

1993-10-01T23:59:59.000Z

152

High Tc Superconductivity  

NLE Websites -- All DOE Office Websites (Extended Search)

by C. Kim (SSRL), D. H. Lu (Stanford), K. M. Shen (Stanford) and Z.-X. Shen (Stanford/SSRL) by C. Kim (SSRL), D. H. Lu (Stanford), K. M. Shen (Stanford) and Z.-X. Shen (Stanford/SSRL) Extensive research efforts to study the novel electronic properties of high-Tc superconductors and their related materials by angle-resolved photoemission spectroscopy at a recently commissioned Beam Line 5-4 (led by Z.-X. Shen) continue to be successful, producing many important results. These results, which are highlighted by five articles recently published in Physical Review Letters and one in Science, brought our understanding steps closer to solving the mystery of the high-Tc superconductivity. With the development of the latest generation of ultra-high resolution electron spectrometers in the past few years, the technique of angle resolved photoemission spectroscopy (ARPES) has recently experienced a renaissance. Nowhere is this revolution more evident than in the study of the high-temperature superconductors, which more than a decade after their discovery, continue to defy theoretical explanation. Recent ARPES experiments performed at Beam Line 5-4 have led to critical new discoveries about the fundamental nature of these mysterious superconductors and are now changing the way that the physics community views these materials. An excellent benchmark for the huge leap in detector resolution and technology is the recent work on Sr2RuO4. Although it belongs to a slightly different family than the high- temperature superconductors, its exotic superconducting mechanism (Tc = 1K) and complex electronic structure make it itself a fascinating material. In the past, due to poor resolutions, ARPES studies on this material were in disagreement with theory and other experimental techniques.

153

Brett Parker | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Brett Parker Brett Parker Recent Presentations "BNL Direct Wind Magnets," (pdf) presentation dedicated to the memory of Pat Thompson given at the 22nd Magnet Technology Conference (MT22), September 11 - 16, 2011, Marseille, France A Review of BNL Direct-Wind Superconducting IR Magnet Experience, (pdf) presented at the 30th Advanced ICFA Beam Dynamics Workshop on High Luminosity e+e- Collisions, October 13 - 16, 2003, Stanford, California The Serpentine Coil Design for BEPC-II Superconducting IR Magnets, (pdf) presented at the "Mini-Workshop on BEPC-II IR Design", January 12 - 16, 2004, Beijing, P.R. China Ma nufacture of a Superconducting Octupole Magnet for the ALPHA Experiment at CERN using the Direct Wind Machine Presentations Prior to 2004 Superconducting Final Focus Magnet Issues (pdf), presented at

154

Mixed-mu superconducting bearings  

DOE Patents (OSTI)

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.

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

1998-03-03T23:59:59.000Z

155

Philosophy 26 High Temperature Superconductivity  

E-Print Network (OSTI)

is the ratio of voltage to current. The resistance of a material tells us how a low resistance, and they are therefore good conductors; other materials, likePhilosophy 26 High Temperature Superconductivity By Ohm's Law, resistance

Callender, Craig

156

EIS-0138: Superconducting Super Collider  

Energy.gov (U.S. Department of Energy (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.

157

Critical State of Superconducting Solenoids  

Science Journals Connector (OSTI)

The critical state is a term introduced by Bean [1] to describe the magnetic properties of a bulk type II superconductor. In this state every region of the superconducting material carries the maximum induced cri...

M. S. Lubell

1966-01-01T23:59:59.000Z

158

Hermetically sealed superconducting magnet motor  

DOE Patents (OSTI)

A hermetically sealed superconducting magnet motor includes a rotor separated from a stator by either a radial gap, an axial gap, or a combined axial and radial gap. Dual conically shaped stators are used in one embodiment to levitate a disc-shaped rotor made of superconducting material within a conduit for moving cryogenic fluid. As the rotor is caused to rotate when the field stator is energized, the fluid is pumped through the conduit.

DeVault, Robert C. (Knoxville, TN); McConnell, Benjamin W. (Knoxville, TN); Phillips, Benjamin A. (Benton Harbor, MI)

1996-01-01T23:59:59.000Z

159

Hermetically sealed superconducting magnet motor  

DOE Patents (OSTI)

A hermetically sealed superconducting magnet motor includes a rotor separated from a stator by either a radial gap, an axial gap, or a combined axial and radial gap. Dual conically shaped stators are used in one embodiment to levitate a disc-shaped rotor made of superconducting material within a conduit for moving cryogenic fluid. As the rotor is caused to rotate when the field stator is energized, the fluid is pumped through the conduit. 6 figs.

DeVault, R.C.; McConnell, B.W.; Phillips, B.A.

1996-07-02T23:59:59.000Z

160

Improved superconducting magnet wire  

DOE Patents (OSTI)

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.

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

1983-08-16T23:59:59.000Z

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


161

Superconducting digital logic amplifier  

SciTech Connect

This paper describes a superconducting digital logic amplifier for interfacing between a Josephson junction logic circuit having output current and a higher voltage semiconductor circuit input. The amplifier comprising: an input terminal for connection to a ; an output terminal for connection to a semiconductor circuit input; an input, lower critical current, Josephson junction having first and second terminals; a first series string of at least three lower critical current Josephson junctions. The first series string being connected to the first terminal of the input Josephson junction such that the first series string is in series with the input Josephson junction to provide a series combination. The input terminal being connected to the first terminal of the input Josephson junction, and with the critical current of the lower critical current Josephson junctions of the input Josephson junction and the first series Josephson junctions being less than the output current of the low voltage Josephson junction circuit; a second series string of at least four higher critical current Josephson junctions. The second string being connected in parallel with the series combination to provide parallel strings having an upper common connection and a lower common connection. The lower common connection being connected to the second terminal of the input Josephson junction and the upper common connection being connected to the output terminal; and a pulsed DC current source connected the parallel strings at the upper common connection. The DC current source having a current at least equal to the critical current of the higher critical current Josephson junctions.

Przybysz, J.X.

1989-08-22T23:59:59.000Z

162

Midwest superconductivity consortium. 1993 Progress report  

SciTech Connect

The Midwest Superconductivity Consortium, MISCON, in the fourth year of operations further strengthened its mission to advance the science and understanding of high T{sub c} superconductivity. The goals of the organization and the individual projects continue to reflect the current needs for new knowledge in the field and the unique capabilities of the institutions involved. Group efforts and cooperative laboratory interactions to achieve the greatest possible synergy under the Consortium continue to be emphasized. Industrial affiliations coupled with technology transfer initiatives were expanded. Activities of the participants during the past year achieved an interactive and high level of performance. The number of notable achievements in the field contributed by Consortium investigators increased. The programmatic research continues to focus upon key materials-related problems in two areas. The first area has a focus upon {open_quotes}Synthesis and Processing{close_quotes} while the second is centered around {open_quotes}Limiting Features in Transport Properties of High T{sub c} Materials{close_quotes}.

Not Available

1994-01-01T23:59:59.000Z

163

Superconductive articles including cerium oxide layer  

DOE Patents (OSTI)

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.

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

1993-01-01T23:59:59.000Z

164

Magnetism and Superconductivity in Iron Pnictides  

SciTech Connect

The discovery of high temperature superconductivity in iron pnictides and chalcogenides has resulted in surprising new insights into high temperature superconductivity and its relationship with magnetism. Here we provide an overview of some of what is known about these materials and in particular about the interplay of magnetism and superconductivity in them. Similarities and contrasts with cuprate superconductors are emphasized and the superconducting pairing is discussed within the framework of spin fluctuation induced pairing.

Singh, David J [ORNL

2012-01-01T23:59:59.000Z

165

Superconducting Topological Fluids in Josephson Junction Arrays  

E-Print Network (OSTI)

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

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

2006-04-21T23:59:59.000Z

166

NETL F 451.1-1/1 Categorical Exclusion (CX) Designation Form  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

44 44 Waukesha Electric System, Inc OE Southern Cal Edison activities Energy Delivery Technologies Div 2010 David Szucs approx. July 2010- January 2015 Irvine, CA "Recovery Act-Fault Current Limiting (FCL) Superconducting Transformer" Southern California Edison will install & operate a prototype FCL superconducting transformer rated 28 MVA, 66kV/12kV service, built by Waukesha Electric, in their MacArthur substation as a demonstration. 07 02 2010 David Szucs Digitally signed by David Szucs DN: cn=David Szucs, o=NETL, ou=EDTD, email=szucs@netl.doe.gov, c=US Date: 2010.07.02 13:16:07 -04'00' 07 16 2010 Fred E. Pozzuto Digitally signed by Fred E. Pozzuto DN: cn=Fred E. Pozzuto, o=USDOE, ou=NETL-Office of Project Facilitation and Compliance, email=fred.pozzuto@netl.doe.gov, c=US

167

Electronic structure of superconductivity refined  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronic structure of superconductivity refined Electronic structure of superconductivity refined Electronic structure of superconductivity refined A team of physicists propose a new model that expands on a little understood aspect of the electronic structure in high-temperature superconductors. July 10, 2008 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

168

Ramesh Gupta | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Ramesh Gupta Ramesh Gupta Ramesh Gupta has always been a leader in the world of superconducting magnets, which are essential to great modern accelerators such as the Relativistic Heavy Ion Collider at BNL, and the Large Hadron Collider at CERN, Switzerland. For the past decade, Lab researchers have been exploring the use of new materials that become superconducting at higher temperatures. Gupta, head of the High Temperature Superconductor (HTS) Research and Development Group in the Superconducting Magnet Division, is among those exploring avenues for HTS magnets that are energy efficient and have magnetic fields that are a million times stronger than the Earth's. These new magnets could revolutionize use in future accelerators, play a key role in energy efficiency and storage, and make possible new

169

HTS Magnet Program | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

HTS Magnet Program HTS Magnet Program High Temperature Superconductors (HTS) have the potential to revolutionize the field of superconducting magnets for particle accelerators, energy storage and medical applications. This is because of the fact that as compared to the conventional Low Temperature Superconductors (LTS), the critical current density (Jc ) of HTS falls slowly both: as a function of increasing field, and as a function of increasing temperature These unique properties can be utilized to design and build: HTS magnets that produce very high fields (20 - 50 T) HTS magnets that operate at elevated temperatures (20 - 77 K) This is a significant step forward over the convention LTS magnets which generally operate at a temperature of ~4 K and with field usually limited

170

Fault Current Limiters  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Fault Fault Current Limiters Superconducting & Solid-state Power Equipment Office of Electricity Delivery and Energy Reliability www.oe.energy.gov Office of Electricity Delivery and Energy Reliability, OE-1 U.S. Department of Energy - 1000 Independence Avenue, SW - Washington, DC 20585 Plugging America Into the Future of Power What are FCLs? A fault is an unintentional short circuit, or partial short-circuit, in an electric circuit. A variety of factors such as lightning, downed power lines, or crossed power lines cause faults. During a fault, excessive current-called fault current- flows through the electrical system often resulting in a failure of one section of that system by causing a

171

Superconducting flux flow digital circuits  

DOE Patents (OSTI)

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.

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

1995-02-14T23:59:59.000Z

172

Dynamical properties of superconducting nanowires  

SciTech Connect

The dynamical properties of thin superconducting wires (nanowires) are studied using numerical simulations based on a one-dimensional time-dependent Ginzburg-Landau equation, which is modified by introducing an order parameter u characterizing the 'purity' of the superconductor material. It is established that relatively long nanowires (with lengths much greater than the coherence length) made of a 'pure' superconductor (u > 1) are characterized by two critical current density values: j{sub c1} and j{sub c2}. For j < j{sub c1}, the total current is entirely superconducting, whereas for j > j{sub c2}, the current is purely normal. In the intermediate region of current densities, j{sub c1} < j < j{sub c2}, the total current contains both superconducting and normal components (mixed state) and the nanowire exhibits the generation of high-frequency electromagnetic waves. The current-voltage characteristics are constructed and the radiation spectrum is obtained. The properties of short superconducting nanowires (with lengths on the order of the coherence length) coincide with those of the Josephson junction. In the case of an 'impure' superconductor (u < 1), the nanowire is characterized by a single critical current density.

Nikolaev, S. V.; Yugay, K. N. [Omsk State University (Russian Federation)], E-mail: yugay_klimenty@mail.ru

2006-02-15T23:59:59.000Z

173

Superconducting flux flow digital circuits  

DOE Patents (OSTI)

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

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

1995-01-01T23:59:59.000Z

174

MICROSTRUCTURE OF SUPERCONDUCTING MGB(2).  

SciTech Connect

Recently, Akimitsu and co-workers [1] discovered superconductivity at 39 K in the intermetallic compound MgB{sub 2}. This discovery provides a new perspective on the mechanism for superconductivity. More specifically, it opens up possibilities for investigation of structure/properties in a new class of materials. With the exceptions of the cuprate and C{sub 60} families of compounds, MgB{sub 2} possesses the highest superconducting transition temperature T{sub c}. Its superconductivity appears to follow the BCS theory, apparently being mediated by electron-phonon coupling. The coherence length of MgB{sub 2} is reported to be longer than that of the cuprates [2]. In contrast to the cuprates, grain boundaries are strongly coupled and current density is determined by flux pinning [2,3]. Presently, samples of MgB{sub 2} commonly display inhomogeneity and porosity on the nanoscale, and are untextured. In spite of these obstacles, magnetization and transport measurements show that polycrystalline samples may carry large current densities circulating across many grains [3,4]. Very high values of critical current densities and critical fields have been recently observed in thin films [5,6]. These attributes suggest possible large scale and electronic applications. The underlying microstructure can be intriguing, both in terms of basic science and in applied areas. Subsequent to the discovery, many papers were published [1-13], most dealing with synthesis, physical properties, and theory. There have yet been few studies of microstructure and structural defects [11, 14]. A thorough understanding of practical superconducting properties can only be developed after an understanding of microstructure is gained. In this work we review transmission electron microscopy (TEM) studies of sintered MgB{sub 2} pellets [14]. Structural defects, including second phase particles, dislocations, stacking faults, and grain boundaries, are analyzed using electron diffraction, electron-energy loss spectroscopy (EELS), high resolution imaging, and structural modeling.

ZHU,Y.; LI,Q.; WU,L.; VOLKOV,V.; GU,G.; MOODENBAUGH,A.R.

2001-07-12T23:59:59.000Z

175

Stress dependent oxidation of sputtered niobium and effects on superconductivity  

SciTech Connect

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

David Henry, M., E-mail: mdhenry@sandia.gov; Wolfley, Steve; Monson, Todd; Clark, Blythe G.; Shaner, Eric; Jarecki, Robert [Sandia National Labs, MESA Fabrication Facility PO Box 5800 MS 1084, Albuquerque, New Mexico 87185-1084 (United States)

2014-02-28T23:59:59.000Z

176

Experimental and Numerical Study of Co-ordination of Resistive-Type Superconductor Fault Current Limiter and Relay Protection  

Science Journals Connector (OSTI)

Superconducting fault current limiter (SFCL) has become one of the most ideal current limiting devices to solve the problem of increasing short-circuit current in high-voltage power grid. This paper...

Y. Chen; S. Li; J. Sheng; Z. Jin; Z. Hong…

2013-11-01T23:59:59.000Z

177

e Lens Solenoid | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Lens Solenoid Electron Lens Solenoid To increase the proton beam luminosity in RHIC, an electron lens (e-lens) magnet system with two superconducting solenoids is being built at Brookhaven National Laboratory. Initial Design of 200 mm, 6T Superconducting Solenoid for e-lens (pdf), R. Gupta, 3/30/10 Iterated Design of 200 mm, 6T Superconducting Solenoid for e-lens (pdf), R. Gupta, 4/6/10 Corrector Designs for Superconducting Solenoid for e-lens (pdf), R. Gupta, 4/14/10 eLens Layout (pdf), P. Kovach, 5/25/10 eLens Main Solenoid (pdf), A. Marone, 5/25/10 Optimization in Corrector Design for Superconducting Solenoid for e-Lens (pdf), R. Gupta, 6/15/10 Main Solenoid Axial Force Retention (pdf), A. Marone 8/24/10 Superconducting Solenoid for e-lens with Fringe Field Coil (pdf), R.

178

Superconducting Cable Having A Felexible Former  

DOE Patents (OSTI)

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.

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

179

Superconducting Cable Having A Flexible Former  

DOE Patents (OSTI)

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.

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

180

Nonlinear Electrodynamics of Superconducting Films  

Science Journals Connector (OSTI)

Microwave-transmission measurements at 9.4 Gc/sec over a wide range of incident power have been used to study the nonlinear electrodynamics of thin superconducting films. By measuring the amplitude and phase of the fundamental transmitted field, the contributions of superelectrons and normal electrons to the electrodynamics of the films have been determined. In low microwave fields the nonlinear behavior of the films can be attributed to the breakup of superconducting pairs in agreement with the Ginzberg-Landau theory. In high microwave fields, regions of normal resistance appear through which a dc bias current cannot avoid passing. Most of the third-harmonic power is generated by these resistive regions.

K. Rose and M. D. Sherrill

1966-05-06T23:59:59.000Z

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


181

Friction domination with superconducting strings  

Science Journals Connector (OSTI)

We investigate the evolution of a superconducting string network with arbitrary, constant string current in the friction dominated regime. In the absence of an external magnetic field the network always reaches a scaling solution. However, for string current stronger than a critical value, it is different than the usual horizon scaling of the nonsuperconducting string case. In this case the friction domination era never ends. Whilst the superconducting string network can be much denser than usually assumed, it can never dominate the universe energy density. It can, however, influence the cosmic microwave background radiation and the formation of large scale structure. When embedded in a primordial magnetic field of sufficient strength, the network never reaches scaling and, thus, eventually dominates the universe evolution.

Konstantinos Dimopoulos and Anne-Christine Davis

1998-01-15T23:59:59.000Z

182

Coherence effects in hole superconductivity  

Science Journals Connector (OSTI)

We discuss the behavior of various observables that depend on matrix elements of operators in the superconducting state within the model of hole superconductivity. In this model, the gap exhibits a linear dependence on the band energy, and the bandwidth depends on the carrier concentration and can become very small for low hole density. We study, in particular, the behavior of ultrasonic attenuation, NMR relaxation rate, and electromagnetic absorption, and present results for parameters expected to be in the range that describes the high-Tc oxides. It is found that the energy dependence of the gap does not give rise to qualitatively different behavior, but significant differences from weak-coupling BCS behavior occur at low hole concentration due to the extreme narrowness of the band.

F. Marsiglio and J. E. Hirsch

1991-12-01T23:59:59.000Z

183

Static forces in a superconducting magnet bearing  

SciTech Connect

Static levitation forces and stiffnesses in a superconducting bearing consisting of concentric ring magnets and a superconducting YBaCuO ring are investigated. In the field-cooled mode a levitation force of 20 N has been achieved. The axial and radial stiffnesses have values of 15 N/mm and 10 N/mm, respectively. An arrangement with two bearings supporting a high speed shaft is now under development. A possible application of superconducting magnetic bearings is flywheels for energy storage.

Stoye, P.; Fuchs, G. [Institut fuer Festkoerper- und Werkstofforschung, Dresden (Germany)] [Institut fuer Festkoerper- und Werkstofforschung, Dresden (Germany); Gawalek, W.; Goernert, P. [Institut fuer Physikalische Hochtechnologie, Jena (Germany)] [Institut fuer Physikalische Hochtechnologie, Jena (Germany); Gladun, A. [Technische Univ., Dresden (Germany)] [Technische Univ., Dresden (Germany)

1995-11-01T23:59:59.000Z

184

Superconductive articles including cerium oxide layer  

DOE Patents (OSTI)

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.

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

1993-11-16T23:59:59.000Z

185

Superconducting inductive displacement detection of a microcantilever  

E-Print Network (OSTI)

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 $\\mu$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.

Andrea Vinante

2014-05-14T23:59:59.000Z

186

Testing gravitational physics with superconducting gravimeters  

E-Print Network (OSTI)

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

Sachie Shiomi

2009-02-24T23:59:59.000Z

187

Fermilab | Science | Particle Accelerators | Advanced Superconducting...  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Test Accelerator is America's only test bed for cutting-edge particle beams and for accelerator research aimed at Intensity Frontier proton accelerators. ASTA...

188

E-Print Network 3.0 - anisotropic superconducting properties...  

NLE Websites -- All DOE Office Websites (Extended Search)

in the Superconductivity Group Background|: i) Experiments... in high-magnetic-fields: Members of the superconductivity group in Durham have published arguably the most......

189

Quantum transport and field-induced superconductivity in carbon nanotubes.  

E-Print Network (OSTI)

?? For my thesis, I conducted experiments to investigate superconductivity and superconducting proximity effect in carbon nanotubes. The measurements are carried out on carbon nanotube… (more)

Yang, Yanfei

2010-01-01T23:59:59.000Z

190

Magnetism and superconductivity observed to exist in harmony  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetism and superconductivity exist in harmony Magnetism and superconductivity observed to exist in harmony Physicists have observed, for the first time in a single exotic phase,...

191

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

E-Print Network (OSTI)

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

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

192

Alternating Current Loss of Strip Arrays as a Model for Resistive Fault Current Limiters  

Science Journals Connector (OSTI)

Hysteretic alternating current (ac) loss P...in arrays of superconducting strip lines are calculated on the bases of the critical state model. For a simplified model of a film-type fault current limiter, we consi...

Yasunori Mawatari; Hirofumi Yamasaki

2000-01-01T23:59:59.000Z

193

Quantum logic gates for superconducting resonator qudits  

SciTech Connect

We study quantum information processing using superpositions of Fock states in superconducting resonators as quantum d-level systems (qudits). A universal set of single and coupled logic gates is theoretically proposed for resonators coupled by superconducting circuits of Josephson junctions. These gates use experimentally demonstrated interactions and provide an attractive route to quantum information processing using harmonic oscillator modes.

Strauch, Frederick W. [Williams College, Williamstown, Massachusetts 01267 (United States)

2011-11-15T23:59:59.000Z

194

Cellulose-Bound Magnesium Diboride Superconductivity  

E-Print Network (OSTI)

Cellulose-Bound Magnesium Diboride Superconductivity Y.L. Lin and M.O. Pekguleryuz Department Canada Abstract--Two-phase superconductor tapes were produced by blending high purity magnesium diboride junctions. I. INTRODUCTION Magnesium diboride was found to be superconducting in 2001 by Nagamatsu et al. [1

Ryan, Dominic

195

Microcalorimeter Magnetic Sensor Geometries Using Superconducting Elements  

SciTech Connect

We describe a numerical code developed to estimate performance of magnetic microcalorimeter configurations, including superconducting elements and SQUID characteristics. We present results of a preliminary design analysis showing that composite sensors with both superconducting and paramagnetic elements should realize substantial gains in magnetic flux signal per magnetization change of the paramagnet, compared to sensors containing only paramagnet.

Boyd, S. T. P. [University of New Mexico, MSC07 4220, Albuquerque NM 87131-0001 (United States); Cantor, R. H. [STAR Cryoelectronics, 25-A Bisbee Ct., Santa Fe NM 87508-1338 (United States)

2009-12-16T23:59:59.000Z

196

Cryogenic structural materials for superconducting magnets  

SciTech Connect

This paper reviews research in the United States and Japan on structural materials for high-field superconducting magnets. Superconducting magnets are used for magnetic fusion energy devices and for accelerators that are used in particle-physics research. The cryogenic structural materials that we review are used for magnet cases and support structures. We expect increased materials requirements in the future.

Dalder, E.N.C.; Morris, J.W. Jr.

1985-02-22T23:59:59.000Z

197

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

SciTech Connect

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.

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

1999-03-01T23:59:59.000Z

198

Molybdenum-rhenium superconducting suspended nanostructures  

SciTech Connect

Suspended superconducting nanostructures of MoRe 50%/50% by weight are fabricated employing commonly used fabrication steps in micro- and nano-meter scale devices followed by wet-etching with Hydro-fluoric acid of a SiO{sub 2} sacrificial layer. Suspended superconducting channels as narrow as 50?nm and length 3??m have a critical temperature of ?6.5?K, which can increase by 0.5?K upon annealing at 400?°C. A detailed study of the dependence of the superconducting critical current and critical temperature upon annealing and in devices with different channel widths reveals that desorption of contaminants is responsible for the improved superconducting properties. These findings pave the way for the development of superconducting electromechanical devices using standard fabrication techniques.

Aziz, Mohsin; Christopher Hudson, David; Russo, Saverio [Centre for Graphene Science, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom)

2014-06-09T23:59:59.000Z

199

Type-1.5 Superconductivity  

Science Journals Connector (OSTI)

We demonstrate the existence of a novel superconducting state in high quality two-component MgB2 single crystalline superconductors where a unique combination of both type-1 (?1/?11/2) superconductor conditions is realized for the two components of the order parameter. This condition leads to a vortex-vortex interaction attractive at long distances and repulsive at short distances, which stabilizes unconventional stripe- and gossamerlike vortex patterns that we have visualized in this type-1.5 superconductor using Bitter decoration and also reproduced in numerical simulations.

Victor Moshchalkov; Mariela Menghini; T. Nishio; Q. H. Chen; A. V. Silhanek; V. H. Dao; L. F. Chibotaru; N. D. Zhigadlo; J. Karpinski

2009-03-16T23:59:59.000Z

200

Microelectronic superconducting crossover and coil  

DOE Patents (OSTI)

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.

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

1994-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "limiting fcl superconducting" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Superconductivity in primitive hexagonal germanium  

Science Journals Connector (OSTI)

We present a first-principles calculation of the electron-phonon coupling constant ? (mass enchancement parameter) for the primitive hexagonal, high-pressure structural phase of Ge (75 GPa?p?105 GPa). Using the calculated value of ?, we estimate the superconducting transition temperature Tc to be in the range of 2 to 7 K. We discuss the contributions to ? from the different phonon modes and its dependence on the phonon frequency, electron-phonon matrix elements, and Fermi-surface nesting. The results are compared with previous calculations for primitive hexagonal Si.

Jose Luis Martins and Marvin L. Cohen

1988-03-01T23:59:59.000Z

202

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

E-Print Network (OSTI)

Characteristic Results of Cryogenic System for 6.6 kV/200 A Inductive Fault Current Limiter Hyoungku Kang, Min-cooled cryogenic cooling system for 1.2 kV/80 A inductive Superconducting Fault Current Limiter (SFCL.830309 TABLE I CHARACTERISTICS OF HTS TAPES tics of the sub-cooled nitrogen cooling system for DC reactor of 6

Chang, Ho-Myung

203

Midwest Superconductivity Consortium - Final Progress Report October 2001  

SciTech Connect

The basic mission of the Consortium was to advance the science and understanding of high-T{sub c} superconductivity and to promote the development of new materials and improved processing technology. Focused group efforts were the key element of the research program. One program area is the understanding of the layered structures involved in candidate materials and the factors that control their formation, stability and relationship superconductor properties. The other program area had a focus upon factors that limit or control the transport properties such as weak links, flux lattice behavior, and interfaces. Interactions among Consortium d with industrial armiates were an integral part of the program.

Bement, Arden L.

2001-10-23T23:59:59.000Z

204

The LHC Superconducting RF System  

E-Print Network (OSTI)

The European Laboratory for Particle Physics (CERN), the largest high energy physics laboratory worldwide, is constructing the Large Hadron Collider (LHC) in the existing 27 km circumference LEP (Large Electron Positron) collider tunnel. For the LHC, superconducting cavities, operating at 4.5 K, will provide the required acceleration field for ramping the beam energy up to 7 TeV and for keeping the colliding proton beams tightly bunched. Superconducting cavities were chosen, not only because of their high acceleration field leading to a small contribution to the machine impedance, but also because of their high stored energy which minimises the effects of periodic transient beam loading associated with the high beam intensity (0.5 A). There will be eight single-cell cavities per beam, each delivering 2 MV (5.3 MV/m) at 400 MHz. The cavities themselves are now being manufactured by industrial firms, using niobium on copper technology which gives full satisfaction at LEP. A complete cavity prototype assembly in...

Boussard, Daniel

1999-01-01T23:59:59.000Z

205

High Temperature Superconducting Underground Cable  

SciTech Connect

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.

Farrell, Roger, A.

2010-02-28T23:59:59.000Z

206

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

SciTech Connect

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.

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

207

Dose Limits  

Energy.gov (U.S. Department of Energy (DOE))

Dose Limits ERAD (Question Posted to ERAD in May 2012) Who do you define as a member of the public for the onsite MEI? This question implies that there may be more than one maximally exposed individual (MEI), one on-site and one off-site, when demonstrating compliance with the Public Dose Limit of DOE Order 458.1. Although all potential MEIs should be considered and documented, as well as the calculated doses and pathways considered, the intent of DOE Order 458.1 is in fact to ultimately identify only one MEI, a theoretical individual who could be either on-site or off-site.

208

RHIC Project | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC Project RHIC Project The Superconducting Magnet Division supplied 1740 magnetic elements, in 888 cryostats, for the RHIC facility at BNL. Of these, 780 magnetic elements were manufactured by Northrop-Grumman (Bethpage, NY) and 360 were made by Everson Electric (Bethlehem, PA). The magnets made in industry used designs developed at BNL. The first cooldown of the magnets for the RHIC engineering run was in 1999. Since then, the magnets have operated very reliably. arc dipole coil and yoke Arc dipole coil and yoke, with magnetic flux lines The magnets provide modest field (3.45 Teslas in the arc dipoles) in a cost-effective design. Key features in the principal bending and focusing magnets include the use of NbTi Rutherford cable, a single-layer coil, and cold iron as both yoke and collar. The magnets operate in forced-flow

209

Superconducting Magnet Division | Brookhaven National Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Magnet Division Superconducting Magnet Division Home Production & Testing LHC Dipole Acceptance APUL Schedule (pdf) Projects Main Projects HTS Magnet Program High Field Magnet R&D Linear Collider Final Focus e Lens Solenoid Correctors for J-PARC Correctors for SuperKEKB IR Magnets LARP APUL Past Projects BEPC-II IR Quadrupoles Bio-Med Variable Field MRI GSI Rapid Cycling Magnets Helical Magnets HERA upgrade LHC IR Dipoles RHIC Publications Search Publications Selected Cryogenic Data Notebook Proceedings of the 1968 Summer Study on Superconducting Devices and Accelerators Meetings & Workshops Safety Environmental, Safety & Health ES&H Documents Lockout-Tagout Personnel Staff Pages Ramesh Gupta Brett Parker Peter Wanderer Pe ter Wanderer, head of Brookhaven's Superconducting Magnet Division,

210

Near-zero modes in superconducting graphene  

E-Print Network (OSTI)

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 ...

Ghaemi, Pouyan

211

New Advances in SuperConducting Materials  

ScienceCinema (OSTI)

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.

None

2014-08-12T23:59:59.000Z

212

Superconducting technology program Sandia 1996 annual report  

SciTech Connect

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.

Roth, E.P.

1997-02-01T23:59:59.000Z

213

Superconductivity for electric power systems: Program overview  

SciTech Connect

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.

Not Available

1995-02-01T23:59:59.000Z

214

Armored spring-core superconducting cable and method of construction  

DOE Patents (OSTI)

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).

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

215

Architecture for high critical current superconducting tapes  

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

216

Dissipative hydride precipitates in superconducting niobium cavities  

SciTech Connect

We report the first direct observation of the microstructural features exhibiting RF losses at high surface magnetic fields of above 100 mT in field emission free superconducting niobium cavities. The lossy areas were identified by advanced thermometry. Surface investigations using different techniques were carried out on cutout samples from lossy areas and showed the presence of dendritic niobium hydrides. This finding has possible implications to the mechanisms of RF losses in superconducting niobium at all field levels.

Romanenko, A.; Cooley, L.D.; /Fermilab; Ciovati, G.; / /Jefferson Lab; Wu, G.; /Argonne

2011-10-01T23:59:59.000Z

217

Two pairing parameters in superconducting grains  

Science Journals Connector (OSTI)

Unlike bulk superconductivity, where one energy scale, the energy gap, characterizes pairing correlations, we show that in small superconducting grains there exist two different such quantities. The first characterizes collective properties of the grain, such as the condensation energy, and the second single-particle properties. To describe these two energy scales, we define two corresponding pairing parameters, and show that although both reduce to the bulk gap for large grains, this occurs at different size scales.

M. Schechter; J. von Delft; Y. Imry; Y. Levinson

2003-02-27T23:59:59.000Z

218

Novel 3-Phase Inductive Fault Current Limiter  

Science Journals Connector (OSTI)

The paper describes the inductive three-phase fault current limiter. In this work I examine the novel arrangements of the perfect closed superconducting loop made of HTS wire. I applied one iron core with 3 limbs and special loops for uniform temperature of the superconducting wire. In this work I present the results of my experiments with this device. I present the static and dynamic measured results of this solution. It has got several advantages e. g. fast switching and less fault power for high-power electric machines. The advantage of the equipment is that in the case of single-phase short circuit the current will decrease in all the three phases. This can be an appropriate solution for high power machines. For example, in the case of high-power electric motor if there is a single-phase breaking or a single phase short circuit, we can decrease the current in the three phases.

Janos Kosa

2012-01-01T23:59:59.000Z

219

Development, Updating and Long-Term Operations of a 10.5 kV HTS Fault Current Limiter  

Science Journals Connector (OSTI)

There are many irreplaceable advantages of high temperature superconducting (HTS) fault current limiter, applying in electric utilities. It is expected to be able to solve excessive fault current problems and to ...

J. Zhang; S. Dai; Y. Teng; D. Zhang; N. Song…

2014-10-01T23:59:59.000Z

220

The superconducting spin valve and triplet superconductivity I.A. Garifullin a,n  

E-Print Network (OSTI)

The superconducting spin valve and triplet superconductivity I.A. Garifullin a,n , P.V. Leksin s t r a c t A review of our recent results on the spin valve effect is presented. We have used coefficient DF and the exchange splitting I of the conduction band in the F layer [1]. For pure Fe the value

Fominov, Yakov

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


221

Superconducting micronets: The Wheatstone bridge  

Science Journals Connector (OSTI)

Using the Ginzburg-Landau theory, a particular superconducting (sc) micronet, called the Wheatstone bridge, is studied. This planar micronet is made of two nodes connected by three thin sc wires. A magnetic field is applied perpendicularly to its plane. The sc-normal second-order phase transition is characterized by only two configurations of the order parameter: cphiA=cphiB and cphiA=-cphiB, where cphiA and cphiB are the order parameters at the nodes. For temperatures near Tc, we show that only the cphiA=cphiB configuration is admissible for fluxes near ?=n?0, where n is an integer and ?0 is the flux quantum. Finally, the exact solution of the nonlinear Ginzburg-Landau equations for one-dimensional systems is numerically fitted to the boundary conditions of the Wheatstone bridge for the two configurations cphiA=cphiB and cphiA=-?B. Graphs of the Gibbs energy and of the spontaneous supercurrent, which for these two configurations is always a screening supercurrent, are given as functions of the total flux. A discontinuous transition between configurations occurs as a function of the flux.

Christine Ammann; Paul Erdös; Stephen B. Haley

1995-05-01T23:59:59.000Z

222

MATHEMATICAL ANALYSIS OF CONDUCTING AND SUPERCONDUCTING TRANSMISSION LINES  

E-Print Network (OSTI)

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

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

223

A Modular Superconducting Generator for Offshore Wind Turbines  

Science Journals Connector (OSTI)

In this study, a new claw-pole type transverse flux superconducting generator topology is presented. The machine has a stationary superconducting field winding, which eliminates electrical brushes and cryocoupler...

Ozan Keysan; Dariusz Olczak…

2013-05-01T23:59:59.000Z

224

Superconducting magnets for toroidal fusion reactors  

SciTech Connect

Fusion reactors will soon be employing superconducting magnets to confine plasma in which deuterium and tritium (D-T) are fused to produce usable energy. At present there is one small confinement experiment with superconducting toroidal field (TF) coils: Tokamak 7 (T-7), in the USSR, which operates at 4 T. By 1983, six different 2.5 x 3.5-m D-shaped coils from six manufacturers in four countries will be assembled in a toroidal array in the Large Coil Test Facility (LCTF) at Oak Ridge National Laboratory (ORNL) for testing at fields up to 8 T. Soon afterwards ELMO Bumpy Torus (EBT-P) will begin operation at Oak Ridge with superconducting TF coils. At the same time there will be tokamaks with superconducting TF coils 2 to 3 m in diameter in the USSR and France. Toroidal field strength in these machines will range from 6 to 9 T. NbTi and Nb/sub 3/Sn, bath cooling and forced flow, cryostable and metastable - various designs are being tried in this period when this new application of superconductivity is growing and maturing.

Haubenreich, P.N.

1980-01-01T23:59:59.000Z

225

Elaboration of the alpha-model derived from the BCS theory of superconductivity  

SciTech Connect

The single-band ?-model of superconductivity (Padamsee et al 1973 J. Low Temp. Phys. 12 387) is a popular model that was adapted from the single-band Bardeen–Cooper–Schrieffer (BCS) theory of superconductivity mainly to allow fits to electronic heat capacity versus temperature T data that deviate from the BCS prediction. The model assumes that the normalized superconducting order parameter ?(T)/?(0) and therefore the normalized London penetration depth ?L(T)/?L(0) are the same as in BCS theory, calculated using the BCS value ?BCS ? 1.764 of ? ? ?(0)/kBTc, where kB is The single-band ?-model of superconductivity (Padamsee et al 1973 J. Low Temp. Phys. 12 387) is a popular model that was adapted from the single-band Bardeen–Cooper–Schrieffer (BCS) theory of superconductivity mainly to allow fits to electronic heat capacity versus temperature T data that deviate from the BCS prediction. The model assumes that the normalized superconducting order parameter ?(T)/?(0) and therefore the normalized London penetration depth ?L(T)/?L(0) are the same as in BCS theory, calculated using the BCS value ?BCS ? 1.764 of ? ? ?(0)/kBTc, where kB is Boltzmann's constant and Tc is the superconducting transition temperature. On the other hand, to calculate the electronic free energy, entropy, heat capacity and thermodynamic critical field versus T, the ?-model takes ? to be an adjustable parameter. Here we write the BCS equations and limiting behaviors for the superconducting state thermodynamic properties explicitly in terms of ?, as needed for calculations within the ?-model, and present plots of the results versus T and ? that are compared with the respective BCS predictions. Mechanisms such as gap anisotropy and strong coupling that can cause deviations of the thermodynamics from the BCS predictions, especially the heat capacity jump at Tc, are considered. Extensions of the ?-model that have appeared in the literature, such as the two-band model, are also discussed. Tables of values of ?(T)/?(0), the normalized London parameter ?(T)/?(0) and ?L(T)/?L(0) calculated from the BCS theory using ? = ?BCS are provided, which are the same in the ?-model by assumption. Tables of values of the entropy, heat capacity and thermodynamic critical field versus T for seven values of ?, including ?BCS, are also presented.

Johnston, David C. [Ames Laboratory

2013-10-14T23:59:59.000Z

226

RHIC Superconducting Accelerator and Electron Cooling Group  

NLE Websites -- All DOE Office Websites (Extended Search)

Organization Chart (PDF) Organization Chart (PDF) Accelerator R&D Division eRHIC R&D Energy Recovery Linac Photocathode R&D Superconducting RF Electron Cooling LARP Center for Accelerator Science and Education C-AD Accelerator R&D Division Superconducting RF Group Group Headed By: Sergey Belomestnykh This web site presents information on the Superconducting Accelerator and RHIC Electron Cooling Group, which is in the Accelerator R&D Division of the Collider-Accelerator Department of Brookhaven National Laboratory. Work is supported mainly by the Division of Nuclear Physics of the US Department of Energy. Upcoming Events: TBD Most recent events: 56 MHz 2nd External Review, March 8-9, 2011 External Review of the Energy Recovery Linac, February 17-18, 2010. Report of the Review Committee

227

J-PARC Correctors | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnet Construction Magnet Construction The final turn of the J-PARC extracted proton beam is a superconducting combined function magnet line. The combined function magnets are dipole cable magnets, typical of cold mass collared magnets, but have been designed to include a large component of quadrupole field. This provides both bending and focussing of the proton beam prior to target impact, where neutrinos will be produced. The BNL Superconducting Magnet Division is using its direct wind facility to produce superconducting corrector magnets to be used in conjunction with the combined function magnets. combined function magnet The first direct wind magnet set designed and fabricated is a combined function magnet with an additional skew dipole. This magnet is intended to be used within the cable collared combined function dipole used for the

228

Superconducting technology program: Sandia 1995 annual report  

SciTech Connect

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.

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

1996-03-01T23:59:59.000Z

229

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

SciTech Connect

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.

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

1984-01-01T23:59:59.000Z

230

Apparatus for characterizing conductivity of superconducting materials  

DOE Patents (OSTI)

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.

Doss, J.D.

1993-12-07T23:59:59.000Z

231

HOM Coupler Optimisation for the Superconducting RF Cavities in ESS  

E-Print Network (OSTI)

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.

Ainsworth, R; Calaga, R

2012-01-01T23:59:59.000Z

232

Superconducting switch concept applied to superconducting undulator phase-error correction  

SciTech Connect

Superconducting undulator (SCU) technology has the potential to significantly enhance the performance of synchrotron radiation sources for storage ring and FEL applications. Since 2002, our team at Lawrence Berkeley National Laboratory has been performing R and D on superconducting undulators, including the fabrication of three Nb{sub 3}Sn prototypes. We have demonstrated experimentally the possibility to provide the prototype with trim coils that could be used for phase error correction. The research effort that we report here demonstrates the possibility to add degrees of freedom to the field correction provided by these coils in a cryogenic environment. By means of bridge of superconducting switches, we can modify the current direction through a trim coil. Here we describe the design of the experimental bridge we fabricated, the results we obtained and finally the generalized concept one could plan to apply to correct the phase errors with trim coils connected to a network of superconducting bridges.

Madur, A.; Trillaud, F.; Dietderich, D.; Marks, S.; Prestemon, S.; Schlueter, R. [LBNL, 1 Cyclotron Road, BERKELEY, CA, 94720 (United States)

2010-06-23T23:59:59.000Z

233

Pseudogap and Superconducting Gap in High-Temperature Superconductors  

NLE Websites -- All DOE Office Websites (Extended Search)

Pseudogap and Superconducting Gap in Pseudogap and Superconducting Gap in High-Temperature Superconductors Two decades after the discovery of first high temperature superconductors, the microscopic mechanism of high-Tc superconductivity remains elusive. In conventional superconductors, it has been well established that electrons form so-called "Cooper pairs" to give rise to superconductivity. The pair binding manifests itself as an energy gap in many spectroscopic measurements. This energy gap, known as superconducting gap, appears at the superconducting transition temperature Tc where the resistance also vanishes. For high temperature superconductors, the story is more complicated. Over a wide region of compositions and temperatures, there exists an energy gap well above Tc. This energy gap is called pseudogap [1], because there is no direct correlation to the superconducting transition. The origin of this pseudogap and its relation to the superconducting gap are believed to hold the key for understanding the mechanism of high-Tc superconductivity - one of the outstanding problems in condensed matter physics. In this regard, researchers Kiyohisa Tanaka and Wei-Sheng Lee, along with their co-workers in Prof. Zhi-Xun Shen's group at Stanford University, have recently made an important discovery about the coexistence of two distinct energy gaps that have opposite doping dependence. Their observation not only provides a natural explanation for the contradictory results about the superconducting gap deduced from different experimental techniques, but also has profound implications on the mechanism of high-Tc superconductivity.

234

Putting Accelerator Technology to Work Fully Superconducting GunFully Superconducting Gun  

E-Print Network (OSTI)

Putting Accelerator Technology to Work Fully Superconducting GunFully Superconducting Gun BNL PS Gun LANL/AES NC or AES FS gun e- 1.5-2.5 MeV 500-300 mA CW * e- 1.6-2.8 MeV 500-300 mA CW Beam cavity with low current beam * NC gun with derated gradient FS gun permits 25% higher current Ilan Ben

235

Ultra-high quality factors in superconducting niobium cavities in ambient magnetic fields up to 190 mG  

E-Print Network (OSTI)

Ambient magnetic field, if trapped in the penetration depth, leads to the residual resistance and therefore sets the limit for the achievable quality factors in superconducting niobium resonators for particle accelerators. Here we show that a complete expulsion of the magnetic flux can be performed and leads to: 1) record quality factors $Q > 2\\times10^{11}$ up to accelerating gradient of 22 MV/m; 2) $Q\\sim3\\times10^{10}$ at 2 K and 16 MV/m in up to 190 mG magnetic fields. This is achieved by large thermal gradients at the normal/superconducting phase front during the cooldown. Our findings open up a way to ultra-high quality factors at low temperatures and show an alternative to the sophisticated magnetic shielding implemented in modern superconducting accelerators.

Romanenko, A; Crawford, A C; Sergatskov, D A; Melnychuk, O

2014-01-01T23:59:59.000Z

236

Superconducting high-pressure phases of disilane  

Science Journals Connector (OSTI)

...Superconducting high-pressure phases of disilane 10.1073/pnas.1005242107 Xilian...DC 20015 High-pressure structures of disilane (Si2H6) are investigated extensively...linear-response calculations for Pm-3m disilane at 275 GPa show a large electron-phonon...

Xilian Jin; Xing Meng; Zhi He; Yanming Ma; Bingbing Liu; Tian Cui; Guangtian Zou; Ho-kwang Mao

2010-01-01T23:59:59.000Z

237

Testing Gravitational Physics with Superconducting Gravimeters  

Science Journals Connector (OSTI)

......being improved in geo- physics.29),30) Therefore...would fall at different rates towards the Sun and other...Testing Gravitational Physics with Superconducting...such dilatonic waves pass the Earth, because of...tests of gravitational physics in the previous sections......

Sachie Shiomi

2008-01-01T23:59:59.000Z

238

Flux Exclusion Superconducting Quantum Metamaterial: Towards  

E-Print Network (OSTI)

. Recently, arrays of Josephson junction devices have been proposed as a possible solution. However-atoms containing Josephson junctions15­19 , experiments have been conducted on single superconducting qubit meta-atoms20,21 and one- dimensional Josephson junction metamaterials22 . The recently discovered class of iron

Zheludev, Nikolay

239

Aluminum in Superconducting Magnets Robert J. Weggel  

E-Print Network (OSTI)

Aluminum in Superconducting Magnets Robert J. Weggel Magnet Optimization Research Engineering is aluminum, either ultrapure, as quenchstabilization matrix metal, and/or alloyed and coldworked and heat for magnets in which the stresses and strains are modest. The strongest aluminum alloy commercially available

McDonald, Kirk

240

Superconductivity and the environment: a Roadmap  

Science Journals Connector (OSTI)

There is universal agreement between the United Nations and governments from the richest to the poorest nations that humanity faces unprecedented global challenges relating to sustainable energy, clean water, low-emission transportation, coping with climate change and natural disasters, and reclaiming use of land. We have invited researchers from a range of eclectic research areas to provide a Roadmap of how superconducting technologies could address these major challenges confronting humanity.Superconductivity has, over the century since its discovery by Kamerlingh Onnes in 1911, promised to provide solutions to many challenges. So far, most superconducting technologies are esoteric systems that are used in laboratories and hospitals. Large science projects have long appreciated the ability of superconductivity to efficiently create high magnetic fields that are otherwise very costly to achieve with ordinary materials. The most successful applications outside of large science are high-field magnets for magnetic resonance imaging, laboratory magnetometers for mineral and materials characterization, filters for mobile communications, and magnetoencephalography for understanding the human brain.The stage is now set for superconductivity to make more general contributions. Humanity uses practically unthinkable amounts of energy to drive our modern way of life. Overall, global power usage has been predicted to almost double from 16.5 to 30 TW in the next four decades (2011 Equinox Summit: Energy 2030 http://wgsi.org/publications-resources).The economy with which electrons carry energy compels the continued quest for efficient superconducting power generation, energy storage, and power transmission. The growing global population requires new arable land and treatment of water, especially in remote areas, and superconductivity offers unique solutions to these problems. Exquisite detectors give warning of changes that are otherwise invisible. Prediction of climate and disasters will be helped by future supercomputer technologies that support huge amounts of data and sophisticated modeling, and with the aid of superconductivity these systems might not require the energy of a large city.We present different sections on applications that could address (or are addressing) a range of environmental issues. The Roadmap covers water purification, power distribution and storage, low-environmental impact transport, environmental sensing (particularly for the removal of unexploded munitions), monitoring the Earth's magnetic fields for earthquakes and major solar activity, and, finally, developing a petaflop supercomputer that only requires 3% of the current supercomputer power provision while being 50 times faster.Access to fresh water. With only 2.5% of the water on Earth being fresh and climate change modeling forecasting that many areas will become drier, the ability to recycle water and achieve compact water recycling systems for sewage or ground water treatment is critical. The first section (by Nishijima) points to the potential of superconducting magnetic separation to enable water recycling and reuse.Energy. The Equinox Summit held in Waterloo Canada 2011 (2011 Equinox Summit: Energy 2030 http://wgsi.org/publications-resources) identified electricity use as humanity's largest contributor to greenhouse gas emissions. Our appetite for electricity is growing faster than for any other form of energy. The communiqué from the summit said 'Transforming the ways we generate, distribute and store electricity is among the most pressing challenges facing society today.... If we want to stabilize CO2 levels in our atmosphere at 550 parts per million, all of that growth needs to be met by non-carbon forms of energy' (2011 Equinox Summit: Energy 2030 http://wgsi.org/publications-resources). Superconducting technologies can provide the energy efficiencies to achieve, in the European Union alone, 33–65% of the required reduction in greenhouse gas emissions according to the Kyoto Protocol (Hartikainen et al 2003 Supercond. Sci. Technol. 16 9

Shigehiro Nishijima; Steven Eckroad; Adela Marian; Kyeongdal Choi; Woo Seok Kim; Motoaki Terai; Zigang Deng; Jun Zheng; Jiasu Wang; Katsuya Umemoto; Jia Du; Pascal Febvre; Shane Keenan; Oleg Mukhanov; Lance D Cooley; Cathy P Foley; William V Hassenzahl; Mitsuru Izumi

2013-01-01T23:59:59.000Z

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


241

Intrinsic Spin-Orbit Coupling in Superconducting Delta-Doped SrTiO3 Heterostructures  

SciTech Connect

We report the violation of the Pauli limit due to intrinsic spin-orbit coupling in SrTiO{sub 3} heterostructures. Via selective doping down to a few nanometers, a two-dimensional superconductor is formed, geometrically suppressing orbital pair-breaking. The spin-orbit scattering is exposed by the robust in-plane superconducting upper critical field, exceeding the Pauli limit by a factor of 4. Transport scattering times several orders of magnitude higher than for conventional thin film superconductors enables a new regime to be entered, where spin-orbit coupling effects arise non-perturbatively.

Bell, Christopher

2011-08-19T23:59:59.000Z

242

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

E-Print Network (OSTI)

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.

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

2015-01-01T23:59:59.000Z

243

Roadmap for the design of a superconducting electron cyclotron resonance ion source for Spiral2  

SciTech Connect

A review of today achieved A/Q = 3 heavy ions beams is proposed. The daily operation A/Q = 3 ion beam intensities expected at Spiral2 are at the limit or above best record 3rd generation electron cyclotron resonance ion source (ECRIS) intensities. The necessity to build a new fully superconducting to fulfill these requirements is outlined. A discussion on the volume of the future source is proposed and the minimum value of 12 liters is derived. An analysis of the x-ray absorption superconducting ECRIS is presented based on VENUS experimental data and geometry. This study underlines the necessity to include a complete x-ray study at the time of source conception. The specifications foreseen for the new ECRIS are presented, followed with the roadmap for the design.

Thuillier, T.; Angot, J.; Lamy, T. [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, 53 rue des martyrs 38026 Grenoble cedex (France); Barue, C.; Canet, C.; Leherissier, P.; Lemagnen, F.; Maunoury, L. [GANIL, BP 55027, 14076 Caen Cedex 5 (France); Peaucelle, C. [Institut de Physique Nucleaire de Lyon, Universite de Lyon, Universite de Lyon 1, CNRS/IN2P3, Villeurbanne (France)

2012-02-15T23:59:59.000Z

244

Tokamak Fusion Core Experiment: design studies based on superconducting and hybrid toroidal field coils. Design overview  

SciTech Connect

This document is a design overview that describes the scoping studies and preconceptual design effort performed in FY 1983 on the Tokamak Fusion Core Experiment (TFCX) class of device. These studies focussed on devices with all-superconducting toroidal field (TF) coils and on devices with superconducting TF coils supplemented with copper TF coil inserts located in the bore of the TF coils in the shield region. Each class of device is designed to satisfy the mission of ignition and long pulse equilibrium burn. Typical design parameters are: major radius = 3.75 m, minor radius = 1.0 m, field on axis = 4.5 T, plasma current = 7.0 MA. These designs relay on lower hybrid (LHRH) current rampup and heating to ignition using ion cyclotron range of frequency (ICRF). A pumped limiter has been assumed for impurity control. The present document is a design overview; a more detailed design description is contained in a companion document.

Flanagan, C.A. (ed.)

1984-10-01T23:59:59.000Z

245

Amplitude distribution of magnetoelastic waves propagating in a vortex field in a superconducting layer  

Science Journals Connector (OSTI)

Magnetic field enters the type ? II superconducting body along a discrete arrangement of magnetic vortex lines. In the dynamic case when the magnetic field vary in time around each such a line a supercurrent flows. So the vorticesinteract one to another with the help of the Lorentz force forming this way a new mechanical field of elastic properties. Moreover those lines arrange themselves in a triangular or quadratic lattice. Such a set is observed if the intensity of the applied to the materialmagnetic field is close to its lower limiting value. The paper aims at investigating amplitude distributions of magnetoelastic waves propagating solely in the vortex field of the superconducting layer. Our attention have been focused on the applied magnetic field intensity influence on those amplitudes for various wave frequencies.

Bogdan T. Maruszewski; Andrzej Drzewiecki; Roman Starosta

2008-01-01T23:59:59.000Z

246

Torsional texturing of superconducting oxide composite articles  

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

247

Processes yielding high superconducting temperatures  

SciTech Connect

It is pointed out that any microscopic description of the new high-T/sub c/ superconductors should take into account a number of important points concerning strong couplings, whatever their nature: absence of the MacMillan limit, absence of a Migdal theorem, and importance of the Brovman-Kagan type of vertices with different singularities depending on the dimensionality. As a consequence, the applicability of standard techniques such as the Eliashberg theory in particular, may be questioned in high-T/sub c/ superconductors.

Beal-Monod, M.T.

1987-12-01T23:59:59.000Z

248

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

NLE Websites -- All DOE Office Websites (Extended Search)

Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity Print Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity Print Working at the ALS, a multi-institutional collaboration led by researchers at ALS and Stanford University has identified a pseudogap phase with a nodal-antinodal dichotomy in ferromagnetic manganese oxide materials (manganites). Even though ferromagnetism and superconductivity do not exist together, the pseudogap state found in these manganites is remarkably similar to that found in high-temperature superconducting copper oxide materials (cuprates). This discovery casts new doubts on any direct link between the pseudogap phase and high-temperature superconductivity and adds fire to the debate over one of the great scientific mysteries of our time: What causes high-temperature superconductivity?

249

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

NLE Websites -- All DOE Office Websites (Extended Search)

Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity Print Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity Print Working at the ALS, a multi-institutional collaboration led by researchers at ALS and Stanford University has identified a pseudogap phase with a nodal-antinodal dichotomy in ferromagnetic manganese oxide materials (manganites). Even though ferromagnetism and superconductivity do not exist together, the pseudogap state found in these manganites is remarkably similar to that found in high-temperature superconducting copper oxide materials (cuprates). This discovery casts new doubts on any direct link between the pseudogap phase and high-temperature superconductivity and adds fire to the debate over one of the great scientific mysteries of our time: What causes high-temperature superconductivity?

250

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

NLE Websites -- All DOE Office Websites (Extended Search)

Pseudogaps, Polarons, and the Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity Pseudogaps, Polarons, and the Mystery of High-Tc Superconductivity Print Wednesday, 26 April 2006 00:00 Working at the ALS, a multi-institutional collaboration led by researchers at ALS and Stanford University has identified a pseudogap phase with a nodal-antinodal dichotomy in ferromagnetic manganese oxide materials (manganites). Even though ferromagnetism and superconductivity do not exist together, the pseudogap state found in these manganites is remarkably similar to that found in high-temperature superconducting copper oxide materials (cuprates). This discovery casts new doubts on any direct link between the pseudogap phase and high-temperature superconductivity and adds fire to the debate over one of the great scientific mysteries of our time: What causes high-temperature superconductivity?

251

ORNL Publishes Study on Superconducting Wire Performance | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

ORNL Publishes Study on Superconducting Wire Performance ORNL Publishes Study on Superconducting Wire Performance ORNL Publishes Study on Superconducting Wire Performance August 23, 2013 - 4:06pm Addthis The Department of Energy's Oak Ridge National Laboratory (ORNL) recently released a new study on advances in superconducting wire technology. A team led by ORNL's Amit Goyal demonstrated that the ability to control nanoscale imperfections in superconducting wires results in materials with excellent and customized performance. The team's findings are published in Nature Publishing Group's Scientific Reports. The full press release and link to the new report are available on ORNL's website. Dr. Goyal, a high temperature superconductivity (HTS) research at ORNL, won the Department's 2011 E.O. Lawrence Award in the inaugural category of

252

Superconductivity with stripes | Argonne National Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Science Science Computing, Environment & Life Sciences Energy Engineering & Systems Analysis Photon Sciences Physical Sciences & Engineering Energy Frontier Research Centers Science Highlights Postdoctoral Researchers The brightness and energy of X-ray beams are critical properties for research. The APS Upgrade will make our X-ray beams brighter, meaning more X-rays can be focused onto a smaller, laser-like spot, allowing researchers to gather more data in greater detail in less time. Superconductivity with stripes November 12, 2013 Tweet EmailPrint The physics of low-temperature superconductivity is fairly well understood, but the ultimate goal of achieving the phenomenon at much higher temperatures remains tantalizingly elusive. The most promising high-temperature superconductor candidates are generally considered to be

253

High-Temperature Superconductivity Cable Demonstration Projects  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Temperature Temperature Superconductivity Cable Demonstration Projects Superconductivity Power Equipment www.oe.energy.gov Phone: 202-586-1411 Office of Electricity Delivery and Energy Reliability, OE-1 U.S. Department of Energy - 1000 Independence Avenue, SW - Washington, DC 20585. Plugging America Into the Future of Power "A National Effort to Introduce New Technology into the Power Delivery Infrastructure" "In order to meet President Obama's ambitious energy goals, we must modernize the nation's electrical grid to improve the transmission, storage and reliability of clean energy across the country and help to move renewable energy from the places it can be produced to the places it can be used. The Department of Energy is working with industry partners to develop the

254

Energy Programs | Center for Emergent Superconductivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Center for Emergent Superconductivity (CES) Center for Emergent Superconductivity (CES) The mission of the CES is to advance the frontier of understanding and control of the materials, mechanisms, and critical currents of superconductors, including existing and new materials, and to communicate Center and other research results throughout national and international communities. More... Principal Investigators CES News Publications Recent CES Presentations EFRC Acknowledgements Reference Document (pdf) Guide to EFRC Science Review Documents (pdf) CES-EFRC Materials Catalog (restricted) CES-EFRC April 2009 Kickoff Meeting (restricted) CES-EFRC 2010 Winter Workshop (restricted) CES Fall Workshop: 2013 | 2012 | 2011 | 2010 April 2, 2012 Review (restricted) Story Archives Recent News atomic-scale microscopy Opposing Phenomena Possible Key to High-Efficiency Electricity Delivery

255

Superconducting cuprate heterostructures for hot electron bolometers  

SciTech Connect

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.

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

256

Manufacturing and Testing of Accelerator Superconducting Magnets  

E-Print Network (OSTI)

Manufacturing of superconducting magnet for accelerators is a quite complex process that is not yet fully industrialized. In this paper, after a short history of the evolution of the magnet design and construction, we review the main characteristics of the accelerator magnets having an impact on the construction technology. We put in evidence how the design and component quality impact on construction and why the final product calls for a total-quality approach. LHC experience is widely discussed and main lessons are spelled out. Then the new Nb3Sn technology, under development for the next generation magnet construction, is outlined. Finally, we briefly review the testing procedure of accelerator superconducting magnets, underlining the close connection with the design validation and with the manufacturing process.

Rossi, L

2014-01-01T23:59:59.000Z

257

A transmission calibration method for superconducting resonators  

E-Print Network (OSTI)

A method is proposed and experimentally explored for \\textit{in-situ} calibration of complex transmission data for superconducting microwave resonators. This cryogenic calibration method accounts for the instrumental transmission response between the vector network analyzer reference plane and the device calibration plane. Once calibrated, the observed resonator response was modeled in detail by two approaches. The first, a phenomenological model based on physically realizable rational functions, enables the extraction of multiple resonance frequencies and widths for coupled resonators without explicit specification of the circuit network. In the second, an ABCD-matrix representation for the distributed transmission line circuit is used to model the observed response from the characteristic impedance and propagation constant. When used in conjunction with electromagnetic simulations, the kinetic inductance fraction can be determined with this method with an accuracy of 2%. Datasets for superconducting microst...

Cataldo, Giuseppe; Barrentine, Emily M; Brown, Ari D; Moseley, Samuel H; U-Yen, Kongpop

2014-01-01T23:59:59.000Z

258

A simple figure of merit for high temperature superconducting switches  

SciTech Connect

The discovery of the new high temperature superconductors has revived interest in many special applications, including superconducting switches. For comparison of switch types, a simple figure of merit based in switch performance is proposed, derived for superconducting switches, and then calculated for thyristors and vacuum switches. The figure of merit is then used to show what critical current density would be needed for superconducting switches to compete with more conventional switches. 46 refs., 1 fig.

Honig, E.M.

1989-01-01T23:59:59.000Z

259

Fabrication and characterization of aluminum airbridges for superconducting microwave circuits  

SciTech Connect

Superconducting microwave circuits based on coplanar waveguides (CPW) are susceptible to parasitic slotline modes which can lead to loss and decoherence. We motivate the use of superconducting airbridges as a reliable method for preventing the propagation of these modes. We describe the fabrication of these airbridges on superconducting resonators, which we use to measure the loss due to placing airbridges over CPW lines. We find that the additional loss at single photon levels is small, and decreases at higher drive powers.

Chen, Zijun; Kelly, J.; Barends, R.; Bochmann, J.; Chen, Yu; Chiaro, B.; Dunsworth, A.; Jeffrey, E.; Mutus, J. Y.; O'Malley, P. J. J.; Neill, C.; Roushan, P.; Sank, D.; Vainsencher, A.; Wenner, J.; White, T. C. [Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States); Megrant, A. [Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States); Department of Materials, University of California, Santa Barbara, California 93106 (United States); Cleland, A. N.; Martinis, John M., E-mail: martinis@physics.ucsb.edu [Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States); California NanoSystems Institute, University of California, Santa Barbara, California 93106-9530 (United States)

2014-02-03T23:59:59.000Z

260

Support system design for a superconducting MRI magnet  

E-Print Network (OSTI)

shields cooled to intermediate temperanires. The rest of the heat transfer is solid conduction through various components. One of these components is the magnet support system. The support system for a superconducting magnet suspends the components at 4.... A design of a support system for a superconducting magnet was developed. This system will be used to suspend the Texas Accelerator Center (TAC) liquid helium cooled, four tesla, one meter bore, superconducting coils (cold mass) inside a room...

Watts, Louis Chad

1993-01-01T23:59:59.000Z

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


261

Superconducting RF systems for eRHIC  

SciTech Connect

The proposed electron-hadron collider eRHIC will consist of a six-pass 30-GeV electron Energy Recovery Linac (ERL) and one of RHIC storage rings operating with energy up to 250 GeV. The collider design extensively utilizes superconducting RF (SRF) technology in both electron and hadron parts. This paper describes various SRF systems, their requirements and parameters.

Belomestnykh S.; Ben-Zvi, I.; Brutus, J.C.; Hahn, H. et al

2012-05-20T23:59:59.000Z

262

High temperature superconductive flux gate magnetometer  

SciTech Connect

This paper proposes a different type of HTS superconducting magnetometer based on the non-linear magnetic behavior of bulk HTS materials. The device design is based on the generation of second harmonics which arise as a result of non-linear magnetization observed in Type-II superconductors. Even harmonics are generated from the non-linear interaction of an ac excitation signal with an external DC magnetic field which acts as a bias signal.

Gershenson, M. (Naval Coastal Systems Center, Panama City, FL (United States))

1991-03-01T23:59:59.000Z

263

Magnetism and superconductivity in quark matter  

E-Print Network (OSTI)

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.

T. Tatsumi; E. Nakano; K. Nawa

2005-06-01T23:59:59.000Z

264

Superconducting nano-layer coating without insulator  

E-Print Network (OSTI)

The superconducting nano-layer coating without insulator layer is studied. The magnetic-field distribution and the forces acting on a vortex are derived. Using the derived forces, the vortex-penetration field and the lower critical magnetic field can be discussed. The vortex-penetration field is identical with the multilayer coating, but the lower critical magnetic field is not. Forces acting on a vortex from the boundary of two superconductors play an important role in evaluations of the free energy.

Kubo, Takayuki

2014-01-01T23:59:59.000Z

265

Optimised quantum hacking of superconducting nanowire single-photon detectors  

Science Journals Connector (OSTI)

We explore bright-light control of superconducting nanowire single-photon detectors (SNSPDs) in the shunted configuration (a practical measure to avoid latching). In an experiment, we...

Tanner, Michael G; Makarov, Vadim; Hadfield, Robert H

2014-01-01T23:59:59.000Z

266

E-Print Network 3.0 - anisotropic superconducting transition...  

NLE Websites -- All DOE Office Websites (Extended Search)

susceptibility is anisotropic... Outline: 1. Superconductivity and Magnetic Fields 2. The Spin-Paramagnetic Transition 3. Spin... indicates an anisotropic ... Source:...

267

SciTech Connect: Ultrasonic signatures at the superconducting...  

Office of Scientific and Technical Information (OSTI)

that extends from room temperature to the superconducting transition. Although polarized neutron scattering studies hint at magnetic order associated with the pseudogap, there is...

268

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

Energy Savers (EERE)

announced that their superconducting magnet system passed a landmark reliability test, demonstrating its potential suitability for wide-scale commercial applications. This...

269

Progress on a Superconducting Planar Undulator in the UK  

SciTech Connect

Superconducting (SC) undulators can potentially reach a higher field, for short period devices, than permanent magnet devices. The latest design work on a proposed superconducting planar undulator being designed in the UK by the STFC is presented. The initial layout of the undulator, including superconducting fill factor and the cryogenic system is presented. Calculations of the wakefield heating effects due to different vacuum vessels and electron beam configurations are also presented. Another important issue for superconducting planar undulators is the effect of engineering tolerances of the pole pieces: the computer simulated effects, for different size pole errors, on the electron beam trajectory and phase error through the device are also shown.

Scott, D. J.; Clarke, J. A. [ASTeC, Daresbury Laboratory, STFC, Warrington, Cheshire (United Kingdom); Baynham, E.; Bradshaw, T.; Brummitt, A.; Burton, G.; Carr, S.; Hills, M.; Lintern, A.; Rochford, J.; Taylor, O.; Watson, S. [Rutherford Appleton Laboratory, STFC, Didcot, Oxfordshire (United Kingdom)

2010-06-23T23:59:59.000Z

270

E-Print Network 3.0 - aluminum-stabilized superconducting cables...  

NLE Websites -- All DOE Office Websites (Extended Search)

New superconducting technology will help America reduce the demand for additional electric power Summary: ,000-amp, 3-phase superconducting cable at American Electric Power's...

271

Josephson scanning tunneling microscopy -- a local and direct probe of the superconducting order parameter  

SciTech Connect

Direct measurements of the superconducting superfluid on the surface of vacuum-cleaved Bi2Sr2CaCu2O8+delta (BSCCO) samples are reported. These measurements are accomplished via Josephson tunneling into the sample using a novel scanning tunneling microscope (STM) equipped with a superconducting tip. The spatial resolution of the STM of lateral distances less than the superconducting coherence length allows it to reveal local inhomogeneities in the pair wavefunction of the BSCCO. Instrument performance is demonstrated first with Josephson measurements of Pb films followed by the layered superconductor NbSe2. The relevant measurement parameter, the Josephson ICRN product, is discussed within the context of both BCS superconductors and the high transition temperature superconductors. The local relationship between the ICRN product and the quasiparticle density of states (DOS) gap are presented within the context of phase diagrams for BSCCO. Excessive current densities can be produced with these measurements and have been found to alter the local DOS in the BSCCO. Systematic studies of this effect were performed to determine the practical measurement limits for these experiments. Alternative methods for preparation of the BSCCO surface are also discussed.

Kimura, Hikari; Dynes, Robert; Barber Jr., Richard. P.; Ono, S.; Ando, Y.

2009-09-01T23:59:59.000Z

272

Magnetic phase diagram of small superconducting two-loop networks  

E-Print Network (OSTI)

The critical magnetic behaviour of simple superconducting micro-networks is illustrat- ed by discussing several properties of super- conducting micro-networks [1-3], see also [4]. This theoretical activity has beenL-277 Magnetic phase diagram of small superconducting two-loop networks J. Riess Centre de

Paris-Sud XI, Université de

273

A CURRENT CONTROLLED VARIABLE DELAY SUPERCONDUCTING TRANSMISSION LINE  

E-Print Network (OSTI)

I I I I 1388 A CURRENT CONTROLLED VARIABLE DELAY SUPERCONDUCTING TRANSMISSION LINE S. M. Anlage, H line. The device makes use of the change in kinetic inductance of a superconducting transmission line, fabrication of transmission lines with such films provides the means for constructing a continuously variable

Anlage, Steven

274

Permanent magnet design for high-speed superconducting bearings  

DOE Patents (OSTI)

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.

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

1996-09-10T23:59:59.000Z

275

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

276

Superconductivity in gallium-substituted Ba8Si46 clathrates  

E-Print Network (OSTI)

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...

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

277

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

Energy.gov (U.S. Department of Energy (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.

278

Singlet oxygen luminescence detection with a fibre-coupled superconducting  

E-Print Network (OSTI)

Singlet oxygen luminescence detection with a fibre-coupled superconducting nanowire single Triplet State Singlet State 1O2 Ground State Oxygen 3O2 Singlet oxygen Free space singlet oxygen luminescence detection Fibre-based singlet oxygen luminescence detection References Superconducting Detector

Greenaway, Alan

279

Non-Abelian Superconducting Pumps Valentina Brosco,1,2  

E-Print Network (OSTI)

Non-Abelian Superconducting Pumps Valentina Brosco,1,2 Rosario Fazio,3,4 F. W. J. Hekking,5; published 17 January 2008) Cooper pair pumping is a coherent process. We derive a general expression for the adiabatic pumped charge in superconducting nanocircuits in the presence of level degeneracy and relate

Joye, Alain

280

STATEMENT OF CONSIDERATIONS REQUEST BY DUPONT SUPERCONDUCTIVITY FOR AN ADVANCE  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DUPONT SUPERCONDUCTIVITY FOR AN ADVANCE DUPONT SUPERCONDUCTIVITY FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN PATENT RIGHTS UNDER DOE CONTRACT NO. DE-FC36-99GO10287; W(A)-99-008; CH-1002 The Petitioner, DuPont Superconductivity (hereinafter "DuPont"), has requested a waiver of domestic and foreign patent rights for all subject inventions arising from its participation under the above referenced contract entitled "High Temperature Superconducting Reciprocating Magnetic Separator". This contract relates to the construction of 1/4 commercial scale High Temperature Superconducting (hereinafter "HTS") Reciprocating Magnetic Separations Unit for the purification ofkaoline clay and titanium dioxide. It is anticipated that this project will be performed in three phases, over a period of

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


281

Los Alamos scientists see new mechanism for superconductivity  

NLE Websites -- All DOE Office Websites (Extended Search)

New mechanism for superconductivity New mechanism for superconductivity Los Alamos scientists see new mechanism for superconductivity Researchers have posited an explanation for superconductivity that may open the door to the discovery of new, unconventional forms of superconductivity. November 24, 2008 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

282

Superconducting phase transitions in ultrathin TiN film.  

SciTech Connect

Building on the complete account of quantum contributions to conductivity, we demonstrate that the resistance of thin superconducting films exhibits a non-monotonic temperature behavior due to the competition between weak localization, electron-electron interaction, and superconducting fluctuations. We show that superconducting fluctuations give rise to an appreciable decrease in the resistance even at temperatures well exceeding the superconducting transition temperature, T{sub c}, with this decrease being dominated by the Maki-Thompson process. The transition to a global phase-coherent superconducting state occurs via the Berezinskii-Kosterlitz-Thouless (BKT) transition, which we observe both by power-law behavior in current-voltage characteristics and by flux flow transport in the magnetic field. The ratio T{sub BKT}/T{sub c} follows the universal relation.

Baturina, T. I.; Postolova, S. V.; Mironov, A. Yu.; Glatz, A.; Baklanov, M. R.; Vinokur, V. M. (Materials Science Division); (A. V. Rzhanov Inst. Semicond. Phys.); (IMEC)

2012-01-01T23:59:59.000Z

283

Surface Impedance in the Surface Superconducting State  

Science Journals Connector (OSTI)

To enable a simple calculation of the microwave surface resistance, the surface superconducting state is approximated by a model in which a layer of uniform order parameter is considered superposed on the normal bulk. Appropriate values for the order parameter and thickness of this layer were chosen with the use of the numerical solutions of the Ginsburg-Landau equations by Fink and Kessinger. A Gorter-Casimir temperature dependence was used for the order parameter and the Maki temperature dependence for ?. Our experiments on Pb-In alloys at frequencies of 9.5, 23, and 55 Gc/sec are in good agreement with the calculations.

Allen Rothwarf; Jonathan I. Gittleman; Bruce Rosenblum

1967-03-10T23:59:59.000Z

284

Nanometric constrictions in superconducting coplanar waveguide resonators  

E-Print Network (OSTI)

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

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

2014-09-03T23:59:59.000Z

285

Lattice Vibrations and Superconductivity in Layered Structures  

E-Print Network (OSTI)

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... monolayers of identical particles, stacked atop one another to form a 21-layer slab. A side view of this system is shown in Fig. 1. The films alternately have atomic masses m and M, with m corresponding to the outermost films. The crys- tal structure...

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

1970-01-01T23:59:59.000Z

286

Modelling and Simulation of Inductive Fault Current Limiters  

Science Journals Connector (OSTI)

Inductive superconducting fault current limiters have already demonstrated their technical viability in electrical networks. Its architecture and robustness make them potentially adequate for distribution networks, and this type of devices is considered as an enabling technology for the advent of embedded generation with renewable energy sources. In order to promote the growth and maturity of these superconducting technologies, fast design tools must be developed, allowing simulating devices with different materials in grids with diverse characteristics. This work presents advances in the development of such tool, which, at present stage, is an effective alternative to software simulations by finite elements methods, reducing dramatically computation time. The algorithms are now compared with experimental results from a laboratory scale prototype, showing the need to refine them.

João Murta Pina; Pedro Pereira; Anabela Pronto; Pedro Arsénio; Tiago Silva

2012-01-01T23:59:59.000Z

287

International Large Coil Task: testing of the largest superconducting toroidal magnet system  

SciTech Connect

The Large Coil Task is an international collaboration of the United States, EURATOM, Japan, and Switzerland to develop large superconducting magnets for fusion reactors. The first tests of all six coils were begun in February 1986 when the 420-ton test array was cooled to 4.2 K. Each of the heavily instrumented coils was tested alone to full design current. Heat perturbations (recovery, simulating nuclear heating, or current-sharing tempeature measurements) to investigate design limits were carried out. Two of the coils have been tested in the full array to full current, producing an 8.1-T maximum field. All coils have performed very well without training or quenching.

Lubell, M.S.; Fietz, W.A.; Haubenreich, P.N.; Lue, J.W.; Luton, J.N.; Shen, S.S.; Okuno, K.; Ulbricht, A.R.; Zichy, J.A.

1986-01-01T23:59:59.000Z

288

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

E-Print Network (OSTI)

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

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

2008-01-01T23:59:59.000Z

289

CX-003061: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

061: Categorical Exclusion Determination 061: Categorical Exclusion Determination CX-003061: Categorical Exclusion Determination Recovery Act-Fault Current Limiting (FCL) Superconducting Transformer CX(s) Applied: A9, B3.6, B4.11 Date: 07/16/2010 Location(s): Irvine, California Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory Southern California Edison will install and operate a prototype fault current limiting superconducting transformer rated 28 megavolt ampere, 66 kilovolt/12 kilovolt service, built by Waukesha Electric, in their MacArthur substation as a demonstration. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-003061.pdf More Documents & Publications CX-002486: Categorical Exclusion Determination CX-002485: Categorical Exclusion Determination CX-00120

290

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

41 - 6850 of 29,416 results. 41 - 6850 of 29,416 results. Download CX-003061: Categorical Exclusion Determination Recovery Act-Fault Current Limiting (FCL) Superconducting Transformer CX(s) Applied: A9, B3.6, B4.11 Date: 07/16/2010 Location(s): Irvine, California Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-003061-categorical-exclusion-determination Download CX-003062: Categorical Exclusion Determination Recovery Act-Fault Current Limiting Superconducting Transformer CX(s) Applied: A11, B3.6 Date: 07/16/2010 Location(s): Schenectady, New York Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-003062-categorical-exclusion-determination

291

Exotic superconducting phases of ultracold atom mixtures on triangular lattices  

Science Journals Connector (OSTI)

We study the phase diagram of two-dimensional Bose-Fermi mixtures of ultracold atoms on a triangular optical lattice, in the limit when the velocity of bosonic condensate fluctuations is much larger than the Fermi velocity. We contrast this work with our previous results for a square lattice system in the work of Mathey et al. [Phys. Rev. Lett. 97, 030601 (2006)]. Using functional renormalization-group techniques we show that the phase diagrams for a triangular lattice contain exotic superconducting phases. For spin-1?2 fermions on an isotropic lattice we find a competition of s-, p-, extended d-, and f-wave symmetries, as well as antiferromagnetic order. For an anisotropic lattice, we further find an extended p-wave phase. A Bose-Fermi mixture with spinless fermions on an isotropic lattice shows a competition between p- and f-wave symmetries. These phases can be traced back to the geometric shapes of the Fermi surfaces in various regimes, as well as the intrinsic frustration of a triangular lattice.

L. Mathey; S.-W. Tsai; A. H. Castro Neto

2007-05-18T23:59:59.000Z

292

Digital quantum simulation of fermionic models with a superconducting circuit  

E-Print Network (OSTI)

Simulating quantum physics with a device which itself is quantum mechanical, a notion Richard Feynman originated, would be an unparallelled computational resource. However, the universal quantum simulation of fermionic systems is daunting due to their particle statistics, and Feynman left as an open question whether it could be done, because of the need for non-local control. Here, we implement fermionic interactions with digital techniques in a superconducting circuit. Focusing on the Hubbard model, we perform time evolution with constant interactions as well as a dynamic phase transition with up to four fermionic modes encoded in four qubits. The implemented digital approach is universal and allows for the efficient simulation of fermions in arbitrary spatial dimensions. We use in excess of 300 single-qubit and two-qubit gates, and reach global fidelities which are limited by gate errors. This demonstration highlights the feasibility of the digital approach and opens a viable route towards analog-digital quantum simulation of interacting fermions and bosons in large-scale solid state systems.

R. Barends; L. Lamata; J. Kelly; L. García-Álvarez; A. G. Fowler; A. Megrant; E. Jeffrey; T. C. White; D. Sank; J. Y. Mutus; B. Campbell; Yu Chen; Z. Chen; B. Chiaro; A. Dunsworth; I. -C. Hoi; C. Neill; P. J. J. O'Malley; C. Quintana; P. Roushan; A. Vainsencher; J. Wenner; E. Solano; John M. Martinis

2015-01-30T23:59:59.000Z

293

Diamagnetic loop measurement in Korea Superconducting Tokamak Advanced Research machine  

SciTech Connect

Diamagnetic loop (DL), which consists of two poloidal loops inside the vacuum vessel, is used to measure the diamagnetic flux during a plasma discharge in the Korea Superconducting Tokamak Advanced Research (KSTAR) machine. The vacuum fluxes in the DL signal can be compensated up to 0.1 mWb by using the coefficients, which are obtained from experimental investigations, in the vacuum flux measurements during vacuum shots under same operational conditions of magnetic coils for plasma experiment in the KSTAR machine. The maximum error in the diamagnetic flux measurement due to the errors of the coefficients was estimated as {approx}0.22 mWb. From the diamagnetic flux measurements for the ohmically heated circular plasmas in the KSTAR machine, the stored energy agrees well with the estimated kinetic energy within the discrepancy of 25%. When the electron cyclotron heating, the neutral beam injection, and the ion cyclotron resonance heating are added to the ohmically heated limiter plasmas, the additional heating effects can be clearly observed from the increase of the stored energy evaluated in the DL measurement.

Bak, J. G.; Lee, S. G.; Kim, H. S. [National Fusion Research Institute, Gwahangno 113, Yuseong-Gu, Daejeon 305-333 (Korea, Republic of)

2011-06-15T23:59:59.000Z

294

Superconducting 112 MHz QWR electron gun  

SciTech Connect

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

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

2011-07-25T23:59:59.000Z

295

Extended Supersymmetry in Gapped and Superconducting Graphene  

E-Print Network (OSTI)

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

Oikonomou, V K

2014-01-01T23:59:59.000Z

296

Extended Supersymmetry in Gapped and Superconducting Graphene  

E-Print Network (OSTI)

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

V. K. Oikonomou

2014-11-30T23:59:59.000Z

297

Simulating weak localization using superconducting quantum circuits  

E-Print Network (OSTI)

Understanding complex quantum matter presents a central challenge in condensed matter physics. The difficulty lies in the exponential scaling of the Hilbert space with the system size, making solutions intractable for both analytical and conventional numerical methods. As originally envisioned by Richard Feynman, this class of problems can be tackled using controllable quantum simulators. Despite many efforts, building an quantum emulator capable of solving generic quantum problems remains an outstanding challenge, as this involves controlling a large number of quantum elements. Here, employing a multi-element superconducting quantum circuit and manipulating a single microwave photon, we demonstrate that we can simulate the weak localization phenomenon observed in mesoscopic systems. By engineering the control sequence in our emulator circuit, we are also able to reproduce the well-known temperature dependence of weak localization. Furthermore, we can use our circuit to continuously tune the level of disorder, a parameter that is not readily accessible in mesoscopic systems. By demonstrating a high level of control and complexity, our experiment shows the potential for superconducting quantum circuits to realize scalable quantum simulators.

Yu Chen; P. Roushan; D. Sank; C. Neill; Erik Lucero; Matteo Mariantoni; R. Barends; B. Chiaro; J. Kelly; A. Megrant; J. Y. Mutus; P. J. J. O'Malley; A. Vainsencher; J. Wenner; T. C. White; Yi Yin; A. N. Cleland; John M. Martinis

2014-03-26T23:59:59.000Z

298

Superconducting materials for large scale applications  

SciTech Connect

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

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

2004-05-06T23:59:59.000Z

299

Superconductivity in La1.56Sr0.44CuO4/La2CuO4 Superlattices  

SciTech Connect

Superlattices of the repeated structure La{sub 1.56}Sr{sub 0.44}CuO{sub 4}/La{sub 2}CuO{sub 4} (LSCO-LCO), where none of the constituents is superconducting, show a superconducting transition of T{prime}{sub c} 25 K. In order to elucidate the nature of the superconducting state we have performed a low-energy {mu}SR study. By applying a magnetic field parallel (Meissner state) and perpendicular (vortex state) to the film planes, we could show that superconductivity is sheet like, resulting in a very anisotropic superconducting state. This result is consistent with a simple charge-transfer model, which takes into account the layered structure and the difference in the chemical potential between LCO and LSCO, as well as Sr interdiffusion. Using a pancake-vortex model we could estimate a strict upper limit of the London penetration depth to 380 nm in these superlattices. The temperature dependence of the muon depolarization rate in field cooling experiments is very similar to what is observed in intercalated BSCCO and suggests that vortex-vortex interaction is dominated by electromagnetic coupling but negligible Josephson interaction.

Bozovic I.; Suter, A.; Morenzoni, E.; Prokscha, T.; Luetkens, H.; Wojek, B.M.; Logvenov, G.; Gozar, A.

2011-12-01T23:59:59.000Z

300

A study on DC hybrid three-phase fault current limiting interrupter for a power distribution system  

Science Journals Connector (OSTI)

For the purpose of protecting electric power system, many researches and developments of fault current limiters are being performed. The authors studied a dc hybrid three-phase fault current limiting interrupter (FCLI) composed of a superconducting reactor and an S/N transition element, connected in series each other. The dc hybrid type fault current limiting interrupter can limit a fault current by means of the inductance of high temperature superconducting (HTS) coil together with the normal transition of HTS bulk material (HTSB). In the case of an accident, the normal transition of the bulk material can be accelerated by the magnetic field of the HTS coil. In this paper, the dc hybrid type fault current limiting interrupter for 5.5 km long 6.6 kV–600 A power distribution system is analyzed, and performances of fault current limitation and interruption are confirmed. Moreover, a reclosing operation is discussed for this power distribution system.

Hongtian Shao; Tomoyuki Satoh; Mitsugi Yamaguchi; Satoshi Fukui; Jun Ogawa; Takao Satoh; Hiroyuki Ishikawa

2005-01-01T23:59:59.000Z

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


301

Fiber Optic Cryogenic Sensors for Superconducting Magnets and Superconducting Power Transmission lines at CERN  

E-Print Network (OSTI)

The design, fabrication and tests of a new generation of superconducting magnets for the upgrade of the LHC require the support of an adequate, robust and reliable sensing technology. The use of Fiber Optic Sensors is becoming particularly challenging for applications in extreme harsh environments such as ultra-low temperatures, high electromagnetic fields and strong mechanical stresses offering perspectives for the development of technological innovations in several applied disciplines.

Chiuchiolo, A; Cusano, A; Bajko, M; Perez, J C; Bajas, H; Giordano, M; Breglio, G; Palmieri, L

2014-01-01T23:59:59.000Z

302

Integrated Surface Topography Characterization of Variously Polished Niobium for Superconducting Particle Accelerators  

SciTech Connect

As superconducting niobium radio-frequency (SRF) cavities approach fundamental material limits, there is increased interest in understanding the details of topographical influences on realized performance limitations. Micro-and nano-roughness are implicated in both direct geometrical field enhancements as well as complications of the composition of the 50 nm surface layer in which the super-currents flow. Interior surface chemical polishing (BCP/EP) to remove mechanical damage leaves surface topography, including pits and protrusions of varying sharpness. These may promote RF magnetic field entry, locally quenching superconductivity, so as to degrade cavity performance. A more incisive analysis of surface topography than the widely-used average roughness is needed. In this study, a power spectral density (PSD) approach based on Fourier analysis of surface topography data acquired by both stylus profilometry and atomic force microscopy (AFM) is being used to distinguish the scale-dependent smoothing effects. The topographical evolution of the Nb surface as a function of different steps of EP is reported, resulting in a novel qualitative and quantitative description of Nb surface topography.

Hui Tian, Charles Reece, Michael Kelley, G. Ribeill

2009-05-01T23:59:59.000Z

303

IMPROVING THE DESIGN AND ANALYSIS OF SUPERCONDUCTING MAGNETS FOR PARTICLE ACCELERATORS  

SciTech Connect

The field quality in superconducting magnets has been improved to a level that it does not appear to be a limiting factor on the performance of RHIC. The many methods developed, improved and adopted during the course of this work have contributed significantly to that performance. One can not only design and construct magnets with better field quality than in one made before but can also improve on that quality after construction. The relative field error ({Delta}B/B) can now be made as low as a few parts in 10{sup {minus}5} at 2/3 of the coil radius. This is about an order of magnitude better than what is generally expected for superconducting magnets. This extra high field quality is crucial to the luminosity performance of RHIC. The research work described here covers a number of areas which all must be addressed to build the production magnets with a high field quality. The work has been limited to the magnetic design of the cross section which in most cases essentially determines the field quality performance of the whole magnet since these magnets are generally long. Though the conclusions to be presented in this chapter have been discussed at the end of each chapter, a summary of them might be useful to present a complete picture. The lessons learned from these experiences may be useful in the design of new magnets. The possibilities of future improvements will also be presented.

GUPTA,R.C.

1996-11-01T23:59:59.000Z

304

Superconducting flux coupled fast switching device from YBCo films. Final report, 1 September 1991-29 February 1992  

SciTech Connect

Applications of high-temperature superconducting (HTSC) materials, especially thin-film YBaCuO (123), to microelectronic devices have been limited by materials-related fabrication problems. Magnetic-flux-coupled devices are less limited by these problems but have not been widely explored. The innovation for this program was demonstration of a flux-coupled device that was: (1) simple to fabricate, (2) based on silicon substrates, (3) shows excellent flux-flow dynamics, and (4) can be implemented in switching or amplifying circuits. In Phase I the authors demonstrated the potential for developing this device utilizing high critical-current YBCO thin films on yttria-stabilized zirconia (YSZ)-buffered Si substrates. The devices are designed to take advantage of these new materials opportunities, are within realistic materials and fabrication constraints, and are projected to operate from dc to at least 10 GHz. The flux-flow devices (FFD) that have been fabricated include: externally-activated magnetic switch, superconducting transformer, and flux-flow (transistor-like) switch. The use of Si wafers not only allows high-quality quality films on large (or very thin) and inexpensive substrates, but also many design configurations with great potential for wafer-scale, hybrid integration with semiconductor electronics. Thin Film Microelectronics, Superconducting Transistor, Three-Terminal Active Device, Pulsed Laser Ablation-Deposition.

Fenner, D.B.

1992-04-30T23:59:59.000Z

305

LHC Magnet Program | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnet Program Magnet Program The Superconducting Magnet Division is building a number of dipole magnets for the Large Hadron Collider (LHC), which is now under construction at CERN in Geneva, Switzerland. Scheduled to begin operation in 2007, this machine will collide beams of protons with the unprecedented energy of 7 TeV per beam to explore the nature of matter at its most basic level (RHIC can collide beams of protons with energies of 0.25 TeV, but is mostly used to collide heavy ions with energies of 0.1 TeV per nucleon). The magnets are being built as part of the US program, recommended by the High Energy Physics Advisory Panel (HEPAP) and approved by Congress, to contribute to the construction and, later, use of that frontier machine by the US high energy physics community. Fermi National Accelerator Laboratory (FNAL) and

306

HERA Upgrade Project | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

HERA Upgrade Project HERA Upgrade Project As part of the HERA luminosity upgrade, 6 superconducting Interaction Region quadrupoles were delivered, accepted, and are in service. These 6 layer magnets were designed to include the main quadrupole focus, a skew quad, a normal and skew dipole, and a final sextupole layer. Because of the physical space constraints imposed by the existing detector region components, the DESY magnets were of necessity designed to be very compact. In addition, they are also are required to operate within the solenoidal detector fields at the collision points, so all construction materials had to be non magnetic. Two types of DESY magnets were fabricated. The first, designated as G0, was a two meter long, constant radius magnet. The second, designated GG, is a

307

J-PARC Correctors | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

J-PARC Correctors J-PARC Correctors Physics Japan is constructing a 50 Gev, high intensity proton accelerator at a site near the Japanese high energy research laboratory, KEK. The project is called J-PARC (Japan Proton Accelerator Research Complex). The site is at Tokai and is part of the Japanese Atomic Energy Research Institute (JAERI). KEK and JAERI are jointly responsible for its construction. J-PARC will serve many uses. One of the uses will be to produce neutrinos that will be directed toward a detector located in Kamiokande, Japan. The neutrinos will be produced when protons are extracted from J-PARC and are directed by magnets in a beam line to strike a target. Further information about the neutrino experiment is available. KEK and the BNL Superconducting Magnet Division are working together to

308

Meetings & Workshops | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Meetings & Workshops Meetings & Workshops S&T Committee Program Review June 22 - 23, 2006 Second Annual VLHC Meeting October 16 - 18, 2000 Workshop on the Effect of Synchrotron Radiation in the VLHC September 18 - 20, 2000 Proceedings of the 1968 Summer Study on Superconducting Devices and Accelerators Upcoming Events JAN 17 Friday East Coast Conference for Undergraduate Women in Physics - Lecture "The Nation's Nuclear Physics Program and the Role of the Government" Presented by Dr. Jehanne Gillo, U.S. Department of Energy, Nuclear Physics 9:30 am, Berkner Hall Auditorium Friday, January 17, 2014, 9:30 am Hosted by: Director's Office JAN 22 Wednesday Brookhaven Lecture "491st Brookhaven Lecture: Juergen Thieme of Photon Sciences Directorate" Presented by Juergen Thieme, Brookhaven Lab's Photon Sciences Directorate

309

LOTO Authorized Personnel | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Lockout/Tagout (LOTO) Personnel Lockout/Tagout (LOTO) Personnel Primary Authorized Employee Have the training and/or experience to exercise group and system-level judgments, and are authorized to lockout and tagout any equipment for which they have division's approval. If coordinated multiple lock and tags are applied by more than one employee, those of the "primary authorized employee" must be the first to be applied and the last to be removed. SMD - LOTO Primary Authorized Personnel Name Phone # Systems/Group Raymond Ceruti Ext. 7116 Mechanical Engineering Technical Support John Cintorino Ext. 2544 Magnet Test & Measurement Joseph D'Ambra Ext. 3764 Superconducting Materials R&D Sebastian Dimaiuta Ext. 5265 Electrical Systems Technical Support Glenn Jochen Ext. 7320 Mechanical Engineering Technical Support

310

The Lichnerowicz-Weitzenboeck formula and superconductivity  

SciTech Connect

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

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

2013-01-15T23:59:59.000Z

311

Superconductive silicon nanowires using gallium beam lithography.  

SciTech Connect

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

Henry, Michael David; Jarecki, Robert Leo,

2014-01-01T23:59:59.000Z

312

Superconducting strip in an oblique magnetic field  

Science Journals Connector (OSTI)

As an example for a seemingly simple but actually intricate problem, we study the Bean critical state in a superconducting strip of finite thickness d and width 2w?d placed in an oblique magnetic field. The analytical solution is obtained to leading order in the small parameter d?w. The critical state depends on how the applied magnetic field is switched on, e.g., at a constant tilt angle, or first the perpendicular and then the parallel field component. For these two basic scenarios we obtain the distributions of current density and magnetic field in the critical states. In particular, we find the shapes of the flux-free core and of the lines separating regions with opposite direction of the critical currents, the detailed magnetic field lines (along the vortex lines), and both components of the magnetic moment. The component of the magnetic moment parallel to the strip plane is a nonmonotonic function of the applied magnetic field.

G. P. Mikitik; E. H. Brandt; M. Indenbom

2004-07-30T23:59:59.000Z

313

Quench anaylsis of MICE spectrometer superconducting solenoid  

SciTech Connect

MICE superconducting spectrometer solenoids fabrication and tests are in progress now. First tests of the Spectrometer Solenoid discovered some issues which could be related to the chosen passive quench protection system. Both solenoids do not have heaters and quench propagation relied on the 'quench back' effect, cold diodes, and shunt resistors. The solenoids have very large inductances and stored energy which is 100% dissipated in the cold mass during a quench. This makes their protection a challenging task. The paper presents the quench analysis of these solenoids based on 3D FEA solution of coupled transient electromagnetic and thermal problems. The simulations used the Vector Fields QUENCH code. It is shown that in some quench scenarios, the quench propagation is relatively slow and some areas can be overheated. They describe ways of improving the solenoids quench protection in order to reduce the risk of possible failure.

Kashikhin, Vladimir; Bross, Alan; /Fermilab; Prestemon, Soren; / /LBL, Berkeley

2011-09-01T23:59:59.000Z

314

Transformer current sensor for superconducting magnetic coils  

DOE Patents (OSTI)

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.

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

1988-01-01T23:59:59.000Z

315

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

E-Print Network (OSTI)

1.3.2 Josephson junctions . . . . . . . 1.4 Superconductingpotential of a Josephson junction. . . . . . SQUID schematicSEM images of Josephson junctions. . . . . Double-angle

Johnson, Jedediah Edward Jensen

2012-01-01T23:59:59.000Z

316

High Power Superconducting Continuous Wave Linacs for Protons and  

Office of Science (SC) Website

Power Superconducting Continuous Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives High Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: High Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions

317

J. Robert Schrieffer and the BCS Theory of Superconductivity  

NLE Websites -- All DOE Office Websites (Extended Search)

J. Robert Schrieffer and the BCS Theory of Superconductivity J. Robert Schrieffer and the BCS Theory of Superconductivity Resources with Additional Information J. Robert Schrieffer Courtesy of NHMFL Robert Schrieffer received his BS from M.I.T. in 1953 and his Ph.D. from the University of Illinois in 1957. Upon entering the University of Illinois, "he immediately began research with Professor John Bardeen. After working out a problem dealing with electrical conduction on semiconductor surfaces, Schrieffer spent a year in the laboratory, applying the theory to several surface problems. In the third year of graduate studies, he joined Bardeen and [Leon] Cooper in developing the theory of superconductivity, which constituted his doctoral dissertation."1 Bardeen, Cooper and Schrieffer were awarded the 1972 Nobel Prize in Physics "for their jointly developed theory of superconductivity, usually called the BCS-theory".

318

Proceedings of the 1968 Summer Study on Superconducting Devices and  

NLE Websites -- All DOE Office Websites (Extended Search)

1968 Summer Study on Superconducting Devices and 1968 Summer Study on Superconducting Devices and Accelerators Brookhaven National Laboratory June 10 - July 19, 1968 1968 summer study on superconducting devices and accelerators at Brookhaven National Laboratory is considered as one of the most important and defining meeting that led to the application of superconductivity in modern particle accelerators and storage rings. One must admire that bold vision, and years of persistent and hard work of number of scientists, engineers and technicians which turned that vision in to reality. Moreover, the research work presented then, serves as a good reference material even today. Given its historical and scientific importance, the entire proceedings of this six week study is made available now on the web for easy and wide access.

319

Towards measuring variations of Casimir energy by a superconducting cavity  

E-Print Network (OSTI)

We consider a Casimir cavity, one plate of which is a thin superconducting film. We show that when the cavity is cooled below the critical temperature for the onset of superconductivity, the sharp variation (in the far infrared) of the reflection coefficient of the film engenders a variation in the value of the Casimir energy. Even though the relative variation in the Casimir energy is very small, its magnitude can be comparable to the condensation energy of the superconducting film, and this gives rise to a number of testable effects, including a significant increase in the value of the critical magnetic field, required to destroy the superconductivity of the film. The theoretical ground is therefore prepared for the first experiment ever aimed at measuring variations of the Casimir energy itself.

Giuseppe Bimonte; Enrico Calloni; Giampiero Esposito; Leopoldo Milano; Luigi Rosa

2005-04-07T23:59:59.000Z

320

Overview of diagnostic system in the experimental advanced superconducting tokamak  

Science Journals Connector (OSTI)

The first plasma was achieved in the experimental advanced superconducting tokamak (EAST) on September 26, 2006....H ? radiation array, 20 triple probes for diverter plasma, a one-channel visible ...

X. Gao

2008-03-01T23:59:59.000Z

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


321

High Temperature Superconducting Racetrack Coils for Electric Motor Applications  

Science Journals Connector (OSTI)

American Superconductor Corporation (ASC) has designed and fabricated racetrack-shaped field coils from PbBSSCO-2223 high temperature superconducting (HTS) wire for a 125 HP, four-pole motor currently being devel...

J. P. Voccio; C. B. Prum; M. J. Navarro…

1997-01-01T23:59:59.000Z

322

Superconductivity in Bundles of Double-Wall Carbon Nanotubes  

E-Print Network (OSTI)

We present electrical and thermal specific heat measurements that show superconductivity in double-wall carbon nanotube (DWCNT) bundles. Clear evidence, comprising a resistance drop as a function of temperature, magnetoresistance ...

Shi, Wu

323

Cryogenic deformation of high temperature superconductive composite structures  

DOE Patents (OSTI)

An improvement in a process of preparing a composite high temperature oxide superconductive wire is provided and involves conducting at least one cross-sectional reduction step in the processing preparation of the wire at sub-ambient temperatures.

Roberts, Peter R. (Groton, MA); Michels, William (Brookline, MA); Bingert, John F. (Jemez Springs, NM)

2001-01-01T23:59:59.000Z

324

SciTech Connect: Enhanced Superconducting Gaps in Trilayer High...  

NLE Websites -- All DOE Office Websites (Extended Search)

Enhanced Superconducting Gaps in Trilayer High-Temperature Bi (2) Sr (2) Ca (2) Cu (3) O (10+delta) Cuprate Superconductor Citation Details In-Document Search Title: Enhanced...

325

Novel Approach to Linear Accelerator Superconducting Magnet System  

SciTech Connect

Superconducting Linear Accelerators include a superconducting magnet system for particle beam transportation that provides the beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered from the same power supply through the common, for the group of cryomodules, electrical bus and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. In the paper also presented the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such approach substantially reduces the magnet system cost and increases the reliability.

Kashikhin, Vladimir; /Fermilab

2011-11-28T23:59:59.000Z

326

Levitation pressure and friction losses in superconducting bearings  

DOE Patents (OSTI)

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

Hull, John R. (Downers Grove, IL)

2001-01-01T23:59:59.000Z

327

13 kA Superconducting Busbars Manufacturing Process  

E-Print Network (OSTI)

In the LHC, the superconducting Main Bending magnets and Quadrupole magnets are series-connected electrically in different excitation circuits by means of superconducting busbars, carrying a maximum current of 13 kA. These superconducting busbars consist of a superconducting Rutherford cable thermally and electrically coupled to a copper section all along the length. The function of the copper section is essentially to provide an alternative path for the magnet current in case of resistive transition. The production of these components was originally outsourced. The decision to import the technology at CERN led to a global re-engineering of the standard process. Although based on the procedures adopted during the LHC construction, a few modifications and improvements have been implemented, profiting of the experience gained in the last few years. This document details the manufacturing process of the 13 kA busbars as it is actually performed at CERN, emphasizing the new solutions adopted during the first mon...

Principe, R; Fornasiere, E

2012-01-01T23:59:59.000Z

328

Characterization of Nb?Sn superconducting strand under pure bending  

E-Print Network (OSTI)

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

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

2005-01-01T23:59:59.000Z

329

Magnetism and Superconductivity Compete in Iron-based Superconductors...  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetism and Superconductivity Compete in Iron-based Superconductors Wednesday, April 30, 2014 HTSC Figure 1 Fig. 1. Measured electronic structure of underdoped Ba1-xKxFe2As2 in...

330

Estimating the cost of large superconducting thin solenoid magnets  

SciTech Connect

The cost of thin superconducting solenoid magnets can be estimated if one knows the magnet stored energy, the magnetic field volume product or the overall mass of the superconducting coil and its cryostat. This report shows cost data collected since 1979 for large superconducting solenoid magnets used in high energy physics. These magnets are characterized in most cases by the use of indirect two phase helium cooling and a superconductor stabilizer of very pure aluminum. This correlation can be used for making a preliminary cost estimate of proposed one of a kind superconducting magnets. The magnet costs quoted include the power supply and quench protection system but the cost of the helium refrigerator and helium distribution system is not included in the estimated cost.

Green, M.A. [Lawrence Berkeley Lab., CA (United States); St. Lorant, S.J. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)

1993-07-01T23:59:59.000Z

331

Luminescence and Squeezing of a Superconducting Light Emitting Diode  

E-Print Network (OSTI)

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

Patrik Hlobil; Peter P. Orth

2015-02-17T23:59:59.000Z

332

Luminescence and Squeezing of a Superconducting Light Emitting Diode  

E-Print Network (OSTI)

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

Hlobil, Patrik

2015-01-01T23:59:59.000Z

333

Superconducting generators for large off shore wind turbines   

E-Print Network (OSTI)

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

Keysan, Ozan

2014-06-30T23:59:59.000Z

334

atlas superconducting magnet: Topics by E-print Network  

NLE Websites -- All DOE Office Websites (Extended Search)

Room temperature, water cooled copper magnets produceSuperconducting Magnet Division TEST RESULTS OF HTS COILS AND AN R&D MAGNET FOR RIA* R. Gupta, M. Anerella, M. Harrison,...

335

Strain-induced time-reversal odd superconductivity in graphene  

E-Print Network (OSTI)

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

Bitan Roy; Vladimir Juricic

2014-07-31T23:59:59.000Z

336

Cooling of superconducting devices by liquid storage and refrigeration unit  

DOE Patents (OSTI)

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

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

2013-08-20T23:59:59.000Z

337

Strong enhancement of superconductivity in a nanosized Pb bridge  

Science Journals Connector (OSTI)

In recent experiments with a superconducting nanosized Pb bridge formed between a scanning tunneling microscope tip and a substrate, superconductivity has been detected at magnetic fields, that are a few times larger than the third (surface) critical field. We describe the observed phenomenon on the basis of a numerical solution of the Ginzburg-Landau equations in a model structure consisting of six conoids. The spatial distribution of the superconducting phase is shown to be strongly inhomogeneous, with a concentration of the superconducting phase near the narrowest part (the “neck”) of the bridge. We show that suppression of superconductivity in the bridge by applied magnetic field or by temperature first occurs near the bases and then in the neck region, what leads to a continuous superconducting-to-normal resistive transition. A position of the transition midpoint depends on temperature and, typically, is by one order of magnitude higher than the second critical field Hc2. We find that the vortex states can be realized in the bridge at low temperatures T/Tcbridge that are characterized by a varying vorticity as a function of the bridge’s height.

V.R. Misko; V.M. Fomin; J.T. Devreese

2001-06-15T23:59:59.000Z

338

Higgsless superconductivity from topological defects in compact BF terms  

E-Print Network (OSTI)

We present a new Higgsless model of superconductivity, inspired from anyon superconductivity but P- and T-invariant and generalizable to any dimension. While the original anyon superconductivity mechanism was based on incompressible quantum Hall fluids as average field states, our mechanism involves topological insulators as average field states. In D space dimensions it involves a (D-1)-form fictitious pseudovector gauge field which originates from the condensation of topological defects in compact low-energy effective BF theories. In the average field approximation, the corresponding uniform emergent charge creates a gap for the (D-2)-dimensional branes via the Magnus force, the dual of the Lorentz force. One particular combination of intrinsic and emergent charge fluctuations that leaves the total charge distribution invariant constitutes an isolated gapless mode leading to superfluidity. The remaining massive modes organise themselves into a D-dimensional charged, massive vector. There is no massive Higgs scalar as there is no local order parameter. When electromagnetism is switched on, the photon acquires mass by the topological BF mechanism. Although the charge of the gapless mode (2) and the topological order (4) are the same as those of the standard Higgs model, the two models of superconductivity are clearly different since the origins of the gap, reflected in the high-energy sectors are totally different. In 2D this type of superconductivity is explicitly realized as global superconductivity in Josephson junction arrays. In 3D this model predicts a possible phase transition from topological insulators to Higgsless superconductors.

M. Cristina Diamantini; Carlo A. Trugenberger

2014-08-29T23:59:59.000Z

339

LANSCE beam current limiter  

SciTech Connect

The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. Active instrumentation, such as the Beam Current Limiter, is a component of the RSS. The current limiter is designed to limit the average current in a beam line below a specific level, thus minimizing the maximum current available for a beam spill accident. The beam current limiter is a self-contained, electrically isolated toroidal beam transformer which continuously monitors beam current. It is designed as fail-safe instrumentation. The design philosophy, hardware design, operation, and limitations of the device are described.

Gallegos, F.R.

1996-06-01T23:59:59.000Z

340

Development of A 1 kA Class Alternating Current Lead System for a Fault Current Limiter  

Science Journals Connector (OSTI)

A thermal design of a 1 kA/6.6 kV class superconducting fault current limiter was discussed, and specifications for a current lead system were obtained. According to these specifications, a 1 kA rms current lead ...

M. Takahashi; T. Kuriyama; H. Nakagome; K. Yamamoto…

1996-01-01T23:59:59.000Z

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


341

The feasibility of low-mass conductors for toroidal superconducting magnets for SSC (Superconducting Super Collider) detectors  

SciTech Connect

An earlier study by Luton and Bonanos concluded that the design and fabrication of superconducting toroidal bending magnets would require a major effort but would be feasible. This study is an extension to examine the feasibility of low-mass conductors for such use. It included a literature search, consultations, with conductor manufacturers, and design calculations, but no experimental work. An unoptimized sample design that used a residual resistivity ratio for aluminum of 1360 and a current density of 3.5 kA/cm{sup 2} over the uninsulated conductor for a 4.5-T toroid with 1 GJ of stored energy obtained a hot-spot temperature of 120 K with a maximum dump voltage of 3.6 kV and 24% of the initial current inductively transferred into the shorted aluminum structure. The stability margin was 200 mJ/cm{sup 3} of cable space. Limiting the quench pressure to 360 atm to give conservative stresses in the sheath and assuming that the whole flow path quenched immediately resulted in helium taps that could be a kilometer apart if the flow friction factor were the same as that experienced in the Westinghouse (W) Large Coil Task (LCT) coil. This indicates that the 520-m conductor length of each of the 72 individual coil segments of a toroid would be a single flow path. If some practical uncertainties can be favorably resolved by producing and testing sample conductors, the use of a conductor with clad-aluminum stabilizer and extruded aluminum-alloy sheath should be feasible and economical. 9 refs., 3 figs.

Luton, J.N.

1990-01-01T23:59:59.000Z

342

Method of constructing a superconducting magnet  

DOE Patents (OSTI)

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.

Satti, John A. (Naperville, IL)

1981-01-01T23:59:59.000Z

343

Flywheel energy storage using superconducting magnetic bearings  

SciTech Connect

Storage of electrical energy on a utility scale is currently not practicable for most utilities, preventing the full utilization of existing base-load capacity. A potential solution to this problem is Flywheel Energy Storage (FES), made possible by technological developments in high-temperature superconducting materials. Commonwealth Research Corporation (CRC), the research arm of Commonwealth Edison Company, and Argonne National Laboratory are implementing a demonstration project to advance the state of the art in high temperature superconductor (HTS) bearing performance and the overall demonstration of efficient Flywheel Energy Storage. Currently, electricity must be used simultaneously with its generation as electrical energy storage is not available for most utilities. Existing storage methods either are dependent on special geography, are too expensive, or are too inefficient. Without energy storage, electric utilities, such as Commonwealth Edison Company, are forced to cycle base load power plants to meet load swings in hourly customer demand. Demand can change by as much as 30% over a 12-hour period and result in significant costs to utilities as power plant output is adjusted to meet these changes. HTS FES systems can reduce demand-based power plant cycling by storing unused nighttime capacity until it is needed to meet daytime demand.

Abboud, R.G. [Commonwealth Research Corp., Chicago, IL (United States); Uherka, K.; Hull, J.; Mulcahy, T. [Argonne National Lab., IL (United States)

1994-04-01T23:59:59.000Z

344

MAGNETIC DESIGN OF A SUPERCONDUCTING AGS SNAKE.  

SciTech Connect

Brookhaven National Laboratory plans to build a partial helical snake for polarized proton acceleration in the AGS. It will be a 3 Tesla superconducting magnet having a magnetic length of 1.9 meter. AGS needs only one magnet and currently there is no plan to build a prototype. Therefore, the first magnet itself must function at the design operating field and provide the required field quality, spin rotation and deflections on the particle beam. New software have been developed that exchanges input/output between the OPERA3d field design program, the Pro-Engineering CAD model and the software that drives the machine to make slots in aluminum cylinders where blocks of 6-around-I NbTi wires are placed. This new software have been used to carry out a number of iterations to satisfy various design requirements and to assure that the profile that is used in making field computations is the same that is used in cutting metal. The optimized coil cross-section is based on a two layer design with both inner and outer layers having five current blocks per quadrant. The ends are based on a design concept that will be used for the first time in accelerator magnets.

GUPTA,R.; LUCCIO,A.; MORGAN,G.; MACKAY,W.; POWER,K.; ROSER,T.; WILLEN,E.; OKAMURA,M.

2003-05-12T23:59:59.000Z

345

New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators  

Energy.gov (U.S. Department of Energy (DOE))

AML Superconductivity and Magnetics, in conjunction with DOE's Argonne National Laboratory, recently announced that their superconducting magnet system passed a landmark reliability test, demonstrating its potential suitability for wide-scale commercial applications.

346

Steady-State Heat Transfer in He II through Porous Superconducting Cable Insulation  

Science Journals Connector (OSTI)

The LHC program includes the study of thermal behavior of the superconducting cables wound in the dipole magnet cooled by superfluid helium (He II). Insulation of these superconducting cables forms the major ... ...

B. J. P. Baudouy; F.-P. Juster; C. Meuris…

1996-01-01T23:59:59.000Z

347

Limited Test Ban Treaty  

National Nuclear Security Administration (NNSA)

Detection System (USNDS), which monitors compliance with the international Limited Test Ban Treaty (LTBT). The LTBT, signed by 108 countries, prohibits nuclear testing in the...

348

Fabrication of superconducting wire using organometallic precursors and infiltration  

SciTech Connect

Organometallic precursors from naphthenic acid and metal nitrates were used for the synthesis of YBCO oxide superconducting compounds. The characteristics of metal naphthenates as organometallic precursors were investigated by IR spectra, viscosity measurements, and infiltration. 123 superconducting compound obtained from 123 naphthenate showed a Tc of 90{degree}K and a rather dense and elongated microstructure. Also, the melting behavior of Ba-cuprates which were used for 123 making was studied. A low-temperature melting process was developed to fabricate silver-sheathed superconducting wire with the powder-in-tube method; flowing argon gas is introduced to the system at 930-945{degree}C to reduce the melting temperature of the 123 compound without silver sheath melting. It resulted in a 90{degree}K Tc superconducting core with dense and locally aligned microstructure. SEM-EDS and XRD analysis, 4-probe resistance and Jc measurements, and carbon-content determinations were carried out to characterize the microstructure, grain alignment, and superconducting properties of the samples.

Lee, Y.J.

1991-01-01T23:59:59.000Z

349

Report on discussions with utility engineers about superconducting generators  

SciTech Connect

This report relates to a series of discussions with electric utility engineers concerning the integration of high-temperature superconducting (HTS) generators into the present electric power system. The current and future interest of the utilities in the purchase and use of HTS generators is assessed. Various performance and economic factors are also considered as part of this inspection of the utility prospects for HTS generators. Integration of HTS generators into the electric utility sector is one goal of the Superconductivity Partnership Initiative (SPI). The SPI, a major part of the Department of Energy (DOE) Superconductivity Program for Electric Systems, features vertical teaming of a major industrial power apparatus manufacturers, a producer of HTS wire, and an end-user with assistance and technical support for the national laboratories. The SPI effort on HTS generators is headed by a General Electric Corporation internal team comprised of the Corporate Research Laboratories, Power Generation Engineering, and Power Systems Group. Intermagnetics General corporation, which assisted in the development of the superconducting coils, is the HTS wire and tape manufacturer. Additional technical support is provided by the national laboratories: Argonne, Los Alamos, and Oak Ridge, and the New York State Institute on Superconductivity. The end-user is represented by Niagara-Mohawk and the Electric Power Research Institute.

none,

1996-03-01T23:59:59.000Z

350

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock wave formation of superconductive ceramic oxide electric and magnetic circuit elements with improved microstructures and mechanical properties. 10 figs.

Nellis, W.J.; Maple, M.B.; Geballe, T.H.

1987-10-23T23:59:59.000Z

351

Proceedings of the 1968 Summer Study on Superconducting Devices and  

NLE Websites -- All DOE Office Websites (Extended Search)

selected cryogenic data notebook selected cryogenic data notebook (Digitized and put on web from the original report : BNL 10200-R, Revised August 1980) Compiled and Edited by J.E. Jensen, W.A. Tuttle, R.B. Stewart, H. Brechna and A.G. Prodell Brookhaven National Laboratory NOTE: The indexing is primitive. A useful place to start may be the Subject Index A PDF viewer is required to see most articles. Cover Page Introduction Subject Index Expanded subject index (under construction) Disclaimer Click here to go to Material Properties Important to the Design of A Large Superconducting Magnet Click Here to View the Proceedings of the 1968 Summer Study on Superconducting Devices and Accelerators Go to the Home Page of the Superconducting Magnet Division (SMD) at BNL Go to the Workshop Page at SMD Go to the Publication Page at SMD

352

SUPERCONDUCTING DIPOLE MAGNETS FOR THE LHC INSERTION REGIONS  

NLE Websites -- All DOE Office Websites (Extended Search)

SUPERCONDUCTING DIPOLE MAGNETS FOR THE LHC INSERTION SUPERCONDUCTING DIPOLE MAGNETS FOR THE LHC INSERTION REGIONS E. Willen, M. Anerella, J. Cozzolino, G. Ganetis, A. Ghosh, R. Gupta, M. Harrison, A. Jain, A. Marone, J. Muratore, S. Plate, J. Schmalzle, P. Wanderer, K.C. Wu, Brookhaven National Laboratory, Upton, NY 11973, USA Abstract Dipole bending magnets are required to change the horizontal separation of the two beams in the LHC. In Intersection Regions (IR) 1, 2, 5, and 8, the beams are brought into collision for the experiments located there. In IR4, the separation of the beams is increased to accommodate the machine's particle acceleration hardware. As part of the US contribution to the LHC Project, BNL is building the required superconducting magnets. Designs have been developed featuring a single

353

A new microphonics measurement method for superconducting RF cavities  

SciTech Connect

Mechanical vibrations of the superconducting cavity, also known as microphonics, cause shifts in the resonant frequency of the cavity. In addition to requiring additional RF power, these frequency shifts can contribute to errors in the closed loop phase and amplitude regulation. In order to better understand these effects, a new microphonics measurement method was developed, and the method was successfully used to measure microphonics on the half-wave superconducting cavity when it was operated in a production style cryostat. The test cryostat held a single ?=0.1 half-wave cavity which was operated at 162.5 MHz [1] and [2]. It's the first time that the National Instruments PXIe-5641R intermediate frequency transceiver has been used for microphonics measurements in superconducting cavities. The new microphonics measurement method and results will be shown and analyzed in this paper.

Gao,Zheng; He,Yuan; Chang,Wei; Powers, Tom [JLAB; Yue,Wei-ming; Zhu,Zheng-long; Chen,Qi

2014-09-01T23:59:59.000Z

354

Uniformly wound superconducting coil and method of making same  

DOE Patents (OSTI)

A coil of superconducting wire for a superconducting magnet having a relaely dense and uniformly spaced winding to enhance the homogeneity and strength of the magnetic field surrounding the coil and a method of winding the same wherein the mandrel used to wind said coil comprises removable spacers and retainers forming a plurality of outwardly opening slots, each of said slots extending generally about the periphery of the mandrel and being sized to receive and outwardly align and retain successive turns of the superconducting wire within each slot as the wire is wound around and laterally across the mandrel to form a plurality of wire ribbons of a predetermined thickness laterally across the mandrel.

Mookerjee, Sumit (Cedar Hill, TX); Weijun, Shen (Beijun, CN); Yager, Billy (Waxahachie, TX)

1994-01-01T23:59:59.000Z

355

Uniformly wound superconducting coil and method of making same  

DOE Patents (OSTI)

A coil of superconducting wire for a superconducting magnet is described having a relatively dense and uniformly spaced winding to enhance the homogeneity and strength of the magnetic field surrounding the coil and a method of winding the same wherein the mandrel used to wind said coil comprises removable spacers and retainers forming a plurality of outwardly opening slots, each of said slots extending generally about the periphery of the mandrel and being sized to receive and outwardly align and retain successive turns of the superconducting wire within each slot as the wire is wound around and laterally across the mandrel to form a plurality of wire ribbons of a predetermined thickness laterally across the mandrel. 8 figures.

Mookerjee, S.; Weijun, S.; Yager, B.

1994-03-08T23:59:59.000Z

356

Fiber Bragg Grating Cryo-Sensors for Superconducting Accelerator Magnets  

E-Print Network (OSTI)

The design, fabrication and tests of the new generation of superconducting magnets for the High Luminosity upgrade of the Large Hadron Collider (HL - LHC) require the support of an adequate sensing technology able to assure the integrity of the strain sensitive and brittle superconducting cables through the whole service life of the magnet: assembly up to 150 MPa, cool down to 1.9 K and powering up to about 16 kA. A precise temperature monitoring is also needed in order to guarantee the safe working condition of the superconducting cables in the power transmission lines (SC - Link) designed to feed the magnet over long distance. Temperature and strain FBGs based monitoring systems have been implemented in the first SC-Link prototype and in two subscale dipole magnets and tested in the cryogenic test facility at CERN at 30 K, 77 K and 1.9 K.

Chiuchiolo, A; Perez, J; Bajas, H; Consales, M; Giordano, M; Breglio, G; Cusano, A

2014-01-01T23:59:59.000Z

357

New phase of matter discovered In superconducting material  

NLE Websites -- All DOE Office Websites (Extended Search)

New phase of matter discovered In superconducting material New phase of matter discovered In superconducting material New phase of matter discovered In superconducting material Tiny crystals, probed with a device called a resonant ultrasound spectrometer, are helping solve the long-time mystery of "pseudogap behavior" in copper oxide superconductors. June 6, 2013 Arkady Shekhter setting up the resonant ultrasound measurement in a flow cryostat. Arkady Shekhter setting up the resonant ultrasound measurement in a flow cryostat. Contact Nancy Ambrosiano Communications Office (505) 667-0471 Email News flash: The pseudogap is indeed a phase of matter. Albert Migliori, LANL Fellow and Seaborg Institute director noted that, "the key effects were so small that extreme attention to eliminating spurious signals

358

Graphite and its Hidden Superconductivity | Stanford Synchrotron Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Graphite and its Hidden Superconductivity Graphite and its Hidden Superconductivity Wednesday, November 20, 2013 - 2:00pm SLAC, Conference Room 137-322 Pablo Esquinazi, University of Leipzig We review different experimental results that indicate the existence of granular superconductivity at high temperatures at graphite interfaces. In particular we will discuss the following experimental results: The temperature and magnetic field dependence of the electrical resistance of bulk and thin graphite samples and its relation with the existence of two-dimensional (2D) interfaces. The anomalous hysteresis in the magnetoresistance observed in graphite thin samples as well as its enhancement restricting the current path within the sample. The Josephson behavior of the current-voltage characteristics with

359

General trend for pressurized superconducting hydrogen-dense materials  

SciTech Connect

The long-standing prediction that hydrogen can assume a metallic state under high pressure, combined with arguments put forward more recently that this state might even be superconducting up to high temperatures, continues to spur tremendous research activities toward the experimental realization of metallic hydrogen. These efforts have however so far been impeded by the enormous challenges associated with the exceedingly large required pressure. Hydrogen-dense materials, of the MH{sub 4} form (where M can be, e.g., Si, Ge, or Sn) or of the MH{sub 3} form (with M being, e.g., Al, Sc, Y, or La), allow for the rather exciting opportunity to carry out a proxy study of metallic hydrogen and associated high-temperature superconductivity at pressures within the reach of current techniques. At least one experimental report indicates that a superconducting state might have been observed already in SiH{sub 4}, and several theoretical studies have predicted superconductivity in pressurized hydrogen-rich materials; however, no systematic dependence on the applied pressure has yet been identified so far. In the present work, we have used first-principles methods in an attempt to predict the superconducting critical temperature (T{sub c}) as a function of pressure (P) for three metal-hydride systems of the MH{sub 3} form, namely ScH{sub 3}, YH{sub 3}, and LaH{sub 3}. By comparing the obtained results, we are able to point out a general trend in the T{sub c}-dependence on P. These gained insights presented here are likely to stimulate further theoretical studies of metallic phases of hydrogen-dense materials and should lead to new experimental investigations of their superconducting properties.

Kim, D. Y.; Scheicher, R. H.; Mao, Ho-kwang; Kang, T. W.; Ahuja, R.

2010-01-01T23:59:59.000Z

360

HTS dc bias coil for 35 kV/90 MVA saturated iron-core fault current limiter  

Science Journals Connector (OSTI)

A superconductive coil with 141,000 ampere-turns designed magnetizing power, made of 17,600 meters of BSCCO 2223 HTS tapes, was fabricated and tested. This coil was built for a 35 kV/90 MVA saturated iron-core fault current limiter. Computer simulations on the performance of the coil were carried out using ANSYS. The critical current of the superconducting coil and the dc resistance of the coil, including the non-superconducting joints, were investigated. Spatial distribution of the magnetic field was measured and compared with the simulation results. In this paper, we will report the configuration and the key parameters of the coil as well as the experimental and simulation results.

W.Z. Gong; J.Y. Zhang; Z.J. Cao; H. Hong; B. Tian; Y. Wang; J.Z. Wang; X.Y. Niu; J. Qiu; S.H. Wang; Y. Xin

2008-01-01T23:59:59.000Z

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


361

Buffer layers for REBCO films for use in superconducting devices  

SciTech Connect

A superconducting article includes a substrate having a biaxially textured surface. A biaxially textured buffer layer, which can be a cap layer, is supported by the substrate. The buffer layer includes a double perovskite of the formula A.sub.2B'B''O.sub.6, where A is rare earth or alkaline earth metal and B' and B'' are different transition metal cations. A biaxially textured superconductor layer is deposited so as to be supported by the buffer layer. A method of making a superconducting article is also disclosed.

Goyal, Amit; Wee, Sung-Hun

2014-06-10T23:59:59.000Z

362

TESTING AND EVALUATION OF SUPERCONDUCTING CABLES FOR THE LHC.  

SciTech Connect

As one of the activities of the US-LHC Accelerator Project, BNL is testing short samples of superconducting cables that will be used in the main LHC dipoles and quadrupoles. The purpose of these tests is to verify that the reels of superconducting cables as supplied by the vendors meet the required critical current specifications. The short-sample testing facility and the computer-assisted testing techniques for acquiring the data will be described. We also describe the data analysis, data storage, and data transmission methods.

THOMAS,R.; GHOSH,A.; MCCHESNEY,D.; JAIN,A.

1999-03-29T23:59:59.000Z

363

Optical data transmission at the superconducting super collider  

SciTech Connect

Digital and analog data transmissions via fiber optics for the Superconducting Super Collider have been investigated. The state of the art of optical transmitters, low loss fiber waveguides, receivers and associated electronics components are reviewed and summarized. Emphasis is placed on the effects of the radiation environment on the performance of an optical data transmission system components. Also, the performance of candidate components of the wide band digital and analog transmission systems intended for deployment of the Superconducting Super Collider Detector is discussed. 27 refs., 15 figs.

Leskovar, B.

1989-02-01T23:59:59.000Z

364

Superconducting travelling wave ring with high gradient accelerating section  

SciTech Connect

Use of a superconducting traveling wave accelerating (STWA) structure instead of a standing wave cavity has major advantages in increasing the accelerating gradient in the ILC. In contrast with standing wave cavity STWA requires feedback loop, which sends wave from the structure output to input, making a superconducting traveling wave ring (STWR). One or few input couplers need to excite STWR and compensate power dissipations due to beam loading. To control traveling wave regime in the structure two independent knobs can be used for tuning both resonant ring frequency and backward wave. We discuss two variants of the STWR with one and two feed couplers.

Avrakhov, P.; Solyak, N.; /Fermilab

2007-06-01T23:59:59.000Z

365

Optical limiting materials  

DOE Patents (OSTI)

Optical limiting materials. Methanofullerenes, fulleroids and/or other fullerenes chemically altered for enhanced solubility, in liquid solution, and in solid blends with transparent glass (SiO.sub.2) gels or polymers, or semiconducting (conjugated) polymers, are shown to be useful as optical limiters (optical surge protectors). The nonlinear absorption is tunable such that the energy transmitted through such blends saturates at high input energy per pulse over a wide range of wavelengths from 400-1100 nm by selecting the host material for its absorption wavelength and ability to transfer the absorbed energy into the optical limiting composition dissolved therein. This phenomenon should be generalizable to other compositions than substituted fullerenes.

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

1998-01-01T23:59:59.000Z

366

Testing of 3-meter Prototype Fault Current Limiting Cables  

SciTech Connect

Two 3-m long, single-phase cables have been fabricated by Ultera from second generation (2G) superconductor supplied by American Superconductor. The first cable was made with two layers of 2G tape conductor and had a critical current of 5,750 A while the second cable had four layers and a critical current of 8,500 A. AC loss was measured for both cables at ac currents of up to 4 kArms. Ultera performed initial fault current studies of both cables in Denmark with limited currents in the range from 9.1 to 44 kA. Results from these tests will provide a basis for a 25-m long, three-phase, prototype cable to be tested at ORNL early next year and a 300-m long, fault current limiting, superconducting cable to be installed in a ConEd substation in New York City.

Gouge, Michael J [ORNL] [ORNL; Duckworth, Robert C [ORNL] [ORNL; Demko, Jonathan A [ORNL] [ORNL; Rey, Christopher M [ORNL] [ORNL; Thompson, James R [ORNL] [ORNL; Lindsay, David T [ORNL] [ORNL; Tolbert, Jerry Carlton [ORNL] [ORNL; Willen, Dag [Ultera] [Ultera; Lentge, Heidi [Ultera] [Ultera; Thidemann, Carsten [Ultera] [Ultera; Carter, Bill [AMSC] [AMSC

2009-01-01T23:59:59.000Z

367

Phonon spectrum of QCD vacuum in magnetic-field-induced superconducting phase  

E-Print Network (OSTI)

In the background of a sufficiently strong magnetic field the vacuum was suggested to become an ideal electric conductor (highly anisotropic superconductor) due to an interplay between the strong and electromagnetic forces. The superconducting ground state resembles an Abrikosov lattice state in an ordinary type-II superconductor: it is an inhomogeneous structure made of a (charged vector) quark-antiquark condensate pierced by vortices. In this paper the acoustic (phonon) vibrational modes of the vortex lattice are studied in the mean-field approach at zero temperature. Using an effective model based on a vector meson dominance, we show that in the infrared limit the longitudinal (transverse) acoustic vibrations of the vortex lattice possess a linear (quadratic) dispersion relation corresponding to type I (type II) Nambu-Goldstone modes.

Chernodub, M N; Verschelde, Henri

2014-01-01T23:59:59.000Z

368

Phonon spectrum of QCD vacuum in magnetic-field-induced superconducting phase  

E-Print Network (OSTI)

In the background of a sufficiently strong magnetic field the vacuum was suggested to become an ideal electric conductor (highly anisotropic superconductor) due to an interplay between the strong and electromagnetic forces. The superconducting ground state resembles an Abrikosov lattice state in an ordinary type--II superconductor: it is an inhomogeneous structure made of a (charged vector) quark-antiquark condensate pierced by vortices. In this paper the acoustic (phonon) vibrational modes of the vortex lattice are studied at zero temperature. Using an effective model based on a vector meson dominance, we show that in the infrared limit the longitudinal (transverse) acoustic vibrations of the vortex lattice possess a linear (quadratic) dispersion relation corresponding to type I (type II) Nambu--Goldstone modes.

M. N. Chernodub; Jos Van Doorsselaere; Henri Verschelde

2014-01-01T23:59:59.000Z

369

Evidence for charge Kondo effect in superconducting Tl-doped PbTe  

SciTech Connect

We report results of low-temperature thermodynamic and transport measurements of Pb{sub 1-x}Tl{sub x}Te single crystals for Tl concentrations up to the solubility limit of approximately x = 1.5%. For all doped samples, we observe a low-temperature resistivity upturn that scales in magnitude with the Tl concentration. The temperature and field dependence of this upturn are consistent with a charge Kondo effect involving degenerate Tl valence states differing by two electrons, with a characteristic Kondo temperature T{sub K} {approx} 6 K. The observation of such an effect supports an electronic pairing mechanism for superconductivity in this material and may account for the anomalously high T{sub c} values.

Fisher, I

2010-01-11T23:59:59.000Z

370

Limited Commercial Maintenance (LCLM) Limited Lawn & Ornamental (LLO)  

E-Print Network (OSTI)

, Limited Commercial Landscape Maintenance, Ornamental & Turf, Private Ag, or General Standards CORE for Limited Commercial Landscape Maintenance (LCLM), you must attend all day to earn the 6 CEUs required. Limited Commercial Maintenance (LCLM) Limited Lawn & Ornamental (LLO) Training & Exams Date

Florida, University of

371

Growth of superconducting Hg-1212 very-thin films  

E-Print Network (OSTI)

High quality epitaxial HgBa2CaCu2O6+delta (Hg- High 1212) films with thickness less than 100 nm have been successfully synthesized using cation-exchange process. The films show the superconducting transition up to similar to 118 K which is close...

Wu, Judy; Xie, Y. Y.; Kang, B. W.; Gapud, A. A.; Aytug, T.; Fang, L.

1999-06-01T23:59:59.000Z

372

Quantized geodesic flow and superconductivity of plasma in fireballs  

E-Print Network (OSTI)

An explanation of stability of fireballs is proposed based on quantum effects in a thin surface layer of negatively charged plasma surrounding a positive kernel of a fireball. We construct a quantization of the geodesic flow on the sphere and study the quantum statistics of fermions confined to a spherical surface. Analogy with the BCS theory of superconductivity is explored; spectral gap is estimated.

M. Zelikin

2007-02-21T23:59:59.000Z

373

DENSITY FUNCTIONAL THEORY OF NORMAL AND SUPERCONDUCTING ELECTRON LIQUIDS: EXPLICIT  

E-Print Network (OSTI)

DENSITY FUNCTIONAL THEORY OF NORMAL AND SUPERCONDUCTING ELECTRON LIQUIDS: EXPLICIT FUNCTIONALS VIAÃ?th University Nathan, Queensland 4111, Australia Abstract The basic idea of density functional theory is to map potential which is a functional of the density. The central task of density functional theory is to #12;nd

Gross, E.K.U.

374

Magnetic preferential orientation of metal oxide superconducting materials  

DOE Patents (OSTI)

A superconductor comprised of a polycrystalline metal oxide such as YBa[sub 2]Cu[sub 3]O[sub 7[minus]X] (where 0 < X < 0.5) exhibits superconducting properties and is capable of conducting very large current densities. By aligning the two-dimensional Cu-O layers which carry the current in the superconducting state in the a- and b-directions, i.e., within the basal plane, a high degree of crystalline axes alignment is provided between adjacent grains permitting the conduction of high current densities. The highly anisotropic diamagnetic susceptibility of the polycrystalline metal oxide material permits the use of an applied magnetic field to orient the individual crystals when in the superconducting state to substantially increase current transport between adjacent grains. In another embodiment, the anisotropic paramagnetic susceptibility of rare-earth ions substituted into the oxide material is made use of as an applied magnetic field orients the particles in a preferential direction. This latter operation can be performed with the material in the normal (non-superconducting) state. 4 figs.

Capone, D.W.; Dunlap, B.D.; Veal, B.W.

1990-07-17T23:59:59.000Z

375

Method for obtaining large levitation pressure in superconducting magnetic bearings  

DOE Patents (OSTI)

A method and apparatus are disclosed for compressing magnetic flux to achieve high levitation pressures. Magnetic flux produced by a magnetic flux source travels through a gap between two high temperature superconducting material structures. The gap has a varying cross-sectional area to compress the magnetic flux, providing an increased magnetic field and correspondingly increased levitation force in the gap. 4 figs.

Hull, J.R.

1997-08-05T23:59:59.000Z

376

Superconducting Magnets for M.H.D. Generators [and Discussion  

Science Journals Connector (OSTI)

...Superconducting Magnets for M.H.D. Generators [and Discussion] P. F. Chester W...their application in large m.h.d. generators. The newly exploited hard superconductors...J in the case of a large m.h.d. generator magnet. It will be shown that this...

1967-01-01T23:59:59.000Z

377

Preparation and characterization of TL-based superconducting thin films  

E-Print Network (OSTI)

A simple method for growth of Tl-based superconducting thin films is described. In this method, the precursor was prepared in a vacuum chamber by deposition of Ba, Ca and Cu metals or a Ba-Ca alloy and Cu metal. The precursor was then oxidized...

Wang, Pingshu

2012-06-07T23:59:59.000Z

378

DESIGN REQUIREMENTS AND OPTIONS FOR FINAL FOCUSING SUPERCONDUCTING MAGNETS  

E-Print Network (OSTI)

of using both high-temperature superconductors and con- ventional low-temperature superconductors and operated in particle accelera- tors!. It should be mentioned that before high-temperature superconductor are investi- gated. The use of high-temperature superconducting materials may offer an attractive, although

California at San Diego, University of

379

Development of superconducting transmission cable. CRADA final report  

SciTech Connect

The purpose of this Cooperative Research and Development Agreement (CRADA) between Oak Ridge National Laboratory (ORNL) and Southwire Company is to develop the technology necessary to proceed to commercialization of high-temperature superconducting (HTS) transmission cables. Power transmission cables are a promising near-term electric utility application for high-temperature superconductivity. Present HTS wires match the needs for a three-phase transmission cable: (1) the wires must conduct high currents in self-field, (2) there are no high forces developed, and (3) the cables may operate at relatively low current density. The commercially-available HTS wires, in 100-m lengths, make construction of a full three-phase, alternating current (ac) transmission cable possible. If completed through the pre-commercialization phase, this project will result in a new capability for electric power companies. The superconducting cable will enable delivery with greater efficiency, higher power density, and lower costs than many alternatives now on the market. Job creation in the US is expected as US manufacturers supply transmission cables to the expanding markets in Asia and to the densely populated European cities where pipe-type cable is prevalent. Finally, superconducting cables may enable delivery of the new, diverse and distributed sources of electricity that will constitute the majority of new installed electrical generation in the world during the coming decades.

Hawsey, R.; Stovall, J.P. [Oak Ridge National Lab., TN (United States); Hughey, R.L.; Sinha, U.K. [Southwire Co., Carrollton, GA (United States)

1997-10-01T23:59:59.000Z

380

Particle pulses from superconducting aluminum tunnel junction detectors  

SciTech Connect

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

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

1991-03-01T23:59:59.000Z

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


381

Magnetic preferential orientation of metal oxide superconducting materials  

DOE Patents (OSTI)

A superconductor comprised of a polycrystalline metal oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-X (where 0superconducting properties and is capable of conducting very large current densities. By aligning the two-dimensional Cu-O layers which carry the current in the superconducting state in the a- and b-directions, i.e., within the basal plane, a high degree of crystalline axes alignment is provided between adjacent grains permitting the conduction of high current densities. The highly anisotropic diamagnetic susceptibility of the polycrystalline metal oxide material permits the use of an applied magnetic field to orient the individual crystals when in the superconducting state to substantially increase current transport between adjacent grains. In another embodiment, the anisotropic paramagnetic susceptibility of rare-earth ions substituted into the oxide material is made use of as an applied magnetic field orients the particles in a preferential direction. This latter operation can be performed with the material in the normal (non-superconducting) state.

Capone, Donald W. (Bolingbrook, IL); Dunlap, Bobby D. (Bolingbrook, IL); Veal, Boyd W. (Downers Grove, IL)

1990-01-01T23:59:59.000Z

382

Superconducting articles of manufacture and method of producing same  

DOE Patents (OSTI)

Bulk coatings of Nb.sub.3 Ge with high superconducting transition temperatures bonded to metallic substrates and a chemical vapor deposition method for producing such coatings on metallic substrates are disclosed. In accordance with the method, a Nb.sub.3 Ge coating having a transition temperature in excess of 21.5 K may be tightly bonded to a copper substrate.

Newkirk, Lawrence R. (Los Alamos, NM); Valencia, Flavio A. (Santa Fe, NM)

1980-01-01T23:59:59.000Z

383

Security Clearances; Limitations  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

SEC. 1072. SECURITY CLEARANCES; LIMITATIONS. SEC. 1072. SECURITY CLEARANCES; LIMITATIONS. (a) In General.-Title III of the Intelligence Reform and Terrorism Prevention Act of 2004 (50 U.S.C. 435b) is amended by adding at the end the following new section: "SEC. 3002. SECURITY CLEARANCES; LIMITATIONS. "(a) Definitions.-In this section: "(1) Controlled substance.-The term `controlled substance' has the meaning given that term in section 102 of the Controlled Substances Act (21 U.S.C. 802). "(2) Covered person.-The term `covered person' means- "(A) an officer or employee of a Federal agency; "(B) a member of the Army, Navy, Air Force, or Marine Corps who is on active duty or is in an active status; and "(C) an officer or employee of a contractor of a Federal agency.

384

Superconducting RF, the History, Challenges and Promise  

SciTech Connect

After a short survey of on-going accelerator applications, I will discuss future applications prospects for this enabling technology, both near term and long term. A selection of technology highlights will serve as an introduction to outstanding issues for all types of applications, from pulsed high gradient to CW medium gradient. Finally I will touch upon the limits of niobium and the prospects of new materials. The talk will be targeted at a general audience.

Hasan Padamsee

2009-11-18T23:59:59.000Z

385

Superconducting RF, the History, Challenges and Promise  

ScienceCinema (OSTI)

After a short survey of on-going accelerator applications, I will discuss future applications prospects for this enabling technology, both near term and long term. A selection of technology highlights will serve as an introduction to outstanding issues for all types of applications, from pulsed high gradient to CW medium gradient. Finally I will touch upon the limits of niobium and the prospects of new materials. The talk will be targeted at a general audience.

Hasan Padamsee

2010-01-08T23:59:59.000Z

386

Heat flux limiting sleeves  

DOE Patents (OSTI)

A heat limiting tubular sleeve extending over only a portion of a tube having a generally uniform outside diameter, the sleeve being open on both ends, having one end thereof larger in diameter than the other end thereof and having a wall thickness which decreases in the same direction as the diameter of the sleeve decreases so that the heat transfer through the sleeve and tube is less adjacent the large diameter end of the sleeve than adjacent the other end thereof.

Harris, William G. (Tampa, FL)

1985-01-01T23:59:59.000Z

387

Linear Collider Final Focus Magnet Construction | Superconducting Magnet  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Cable Winding Tests Superconducting Cable Winding Tests To increase the transfer function, a 6 around 1 cable was next used. This cable is more efficient because it allows the packing of more conductor within the volume surrounding the support tube. This also lowers the inductance of the coil, making quench protection easier, but requires a higher operating current. Traded off is the minimum radius of curvature that can be tolerated by the bonding process as well as the insulation integrity. For this test, the first layer was designed for a length of 8 inches, and the second layer is 6 inches long. The lengths were chosen to allow inspection of the different features which were designed in. The pole spacers on the first layer for this test were chosen to be solid copper wire, instead of the standard G-10 spacer. The copper allows for a

388

High Field Magnet R&D |Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

High Field Magnet R&D High Field Magnet R&D The Superconducting Magnet Division is developing advanced magnet designs and magnet-related technologies for high field accelerator magnets. We are currently working on magnets for three inter-related programs: High Field Magnets for Muon Collider Papers, Presentations Common Coil Magnets Papers, Presentations Interaction Region Magnets Papers, Presentations High Temperature Superconductor (HTS) Magnets Papers, Presentations This is part of a multi-lab superconducting magnet development program for new accelerator facilities that would be part of the U.S. High Energy Physics program. These programs (@BNL, @FNAL, @LBNL) are quite complimentary to each other, so that magnet designs and technologies developed at one laboratory can be easily transferred to another. The BNL

389

A Toy Model Study of Decay Trapping | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

A Toy Model Study of Decay Trapping, reported by Brett Parker A Toy Model Study of Decay Trapping, reported by Brett Parker Introduction A group from the BNL Superconducting Magnet Division is looking at various options for dipole magnets which would be suitable for use in a muon storage ring that is used as a neutrino factory. Since the useful neutrino beams from a neutrino factory come from straight sections it is desirable to minimize the rings arc circumference, in relation to straight section length, in order to ensure that the fraction of muons which decay in the straight section is as large as possible. Therefore superconducting magnets, with higher B-fields and smaller bend radii, are reasonable to consider for this application. Unfortunately the decay electrons generated along with the neutrinos carry on average about a third of the original

390

Project Fact Sheet Columbus HTS Power Cable Superconductivity  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Columbus Columbus HTS Power Cable Superconductivity Partnerships with Industry www.oe.energy.gov Phone: 202 \ 586-1411 Office of Electricity Delivery and Energy Reliability, OE-1 U.S. Department of Energy - 1000 Independence Avenue, SW - Washington, DC 20585 Plugging America Into the Future of Power This project involves field-testing of a long-length high-temperature superconducting (HTS) cable under real environmental stresses and real electrical loads. The cable system forms an important electrical link in a util- ity substation in Columbus, Ohio. What are its Primary aPPlications? HTS power cables are used for electricity transmission and distribution. The Columbus cable is a distribution cable, conducting electricity within a local grid. What are the Benefits to Utilities?

391

GSI Rapid Cycling Magnets Project | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

GSI Rapid Cycling Magnets Project GSI Rapid Cycling Magnets Project While superconducting magnets easily achieve higher magnetic fields at lower cost than conventional electromagnets, it is very difficult to ramp superconducting magnets very quickly. But exactly that is needed at the planned new facility of GSI, the Gesellschaft für Schwerionenforschung (Institute for Heavy Ion Research), in Darmstadt, Germany. In the magnets of the SIS 200 ring, one of the components of the new facility, the magnetic field must be ramped from 0.5 Tesla to 4 Tesla at a rate of 1 Tesla per second. This ramp rate is almost 25 times faster than the ramp rate of the Relativistic Heavy Ion Collider (RHIC) magnets at Brookhaven National Lab (BNL), which ramp at a rate of 0.042 Tesla per second. While the SIS 200 magnets also require a slightly higher field strength than the

392

Decay Processes in the Presence of Thin Superconducting Films  

E-Print Network (OSTI)

In a recent paper [Phys. Rev. Lett. 97, 070401 (2006)] the transition rate of magnetic spin-flip of a neutral two-level atom trapped in the vicinity of a thick superconducting body was studied. In the present paper we will extend these considerations to a situation with an atom at various distances from a dielectric film. Rates for the corresponding electric dipole-flip transition will also be considered. The rates for these atomic flip transitions can be reduced or enhanced, and in some situations they can even be completely suppressed. For a superconducting film or a thin film of a perfect conducting material various analytical expressions are derived that reveals the dependence of the physical parameters at hand.

Per K. Rekdal; Bo-Sture K. Skagerstam

2006-09-20T23:59:59.000Z

393

Accurate estimates for magnetic bottles in connection with superconductivity  

E-Print Network (OSTI)

Motivated by the theory of superconductivity and more precisely by the problem of the onset of superconductivity in dimension two, many papers devoted to the analysis in a semi-classical regime of the lowest eigenvalue of the Schr\\"odinger operator with magnetic field have appeared recently. Here we would like to mention the works by Bernoff-Sternberg, Lu-Pan, Del Pino-Felmer-Sternberg and Helffer-Morame and also Bauman-Phillips-Tang for the case of a disc. In the present paper we settle one important part of this question completely by proving an asymptotic expansion to all orders for low-lying eigenvalues for generic domains. The word `generic' means in this context that the curvature of the boundary of the domain has a unique non-degenerate maximum.

S. Fournais; B. Helffer

2004-11-16T23:59:59.000Z

394

Ground-state geometric quantum computing in superconducting systems  

SciTech Connect

We present a theoretical proposal for the implementation of geometric quantum computing based on a Hamiltonian which has a doubly degenerate ground state. Thus the system which is steered adiabatically, remains in the ground-state. The proposed physical implementation relies on a superconducting circuit composed of three SQUIDs and two superconducting islands with the charge states encoding the logical states. We obtain a universal set of single-qubit gates and implement a nontrivial two-qubit gate exploiting the mutual inductance between two neighboring circuits, allowing us to realize a fully geometric ground-state quantum computing. The introduced paradigm for the implementation of geometric quantum computing is expected to be robust against environmental effects.

Solinas, P. [Department of Applied Physics/COMP, Aalto University, P. O. Box 15100, FI-00076 Aalto (Finland); Pirkkalainen, J.-M. [Department of Applied Physics/COMP, Aalto University, P. O. Box 15100, FI-00076 Aalto (Finland); Low Temperature Laboratory, Aalto University, P. O. Box 13500, FI-00076 Aalto (Finland); Moettoenen, M. [Department of Applied Physics/COMP, Aalto University, P. O. Box 15100, FI-00076 Aalto (Finland); Low Temperature Laboratory, Aalto University, P. O. Box 13500, FI-00076 Aalto (Finland); Australian Research Council Centre of Excellence for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, New South Wales 2052 (Australia)

2010-11-15T23:59:59.000Z

395

Fate of False Vacuum in Superconducting Flux Qubits  

E-Print Network (OSTI)

We propose a similarity between the scenario of fate of false vacuum in cosmology at early universe and the situation in where the quantum state decays in superconducting Flux qubit. This is due to the fact that both cases have two homogeneous stable equilibrium states in scalar field, which in quantum theory, could penetrate through the barrier in different possibilities and hence considered unstable decaying in time. In quantum computation, decay rate is among the most important factors in characteristics of the system like coherency, reliability, measurement fidelity, etc. In this considered potential, the decay rate from the penetrating (False vacuum) state to the stable (absolute minimum) state is achieved to leading order in Planck constant by the approach of Instanton model. In case of the superconducting flux qubit having thin barrier potential, the decay rate is calculated and its relations with actual set of parameters in flux qubit design are introduced.

Rad, Ali Izadi; Fardmanesh, Mehdi

2014-01-01T23:59:59.000Z

396

Fate of False Vacuum in Superconducting Flux Qubits  

E-Print Network (OSTI)

We propose a similarity between the scenario of fate of false vacuum in cosmology at early universe and the situation in where the quantum state decays in superconducting Flux qubit. This is due to the fact that both cases have two homogeneous stable equilibrium states in scalar field, which in quantum theory, could penetrate through the barrier in different possibilities and hence considered unstable decaying in time. In quantum computation, decay rate is among the most important factors in characteristics of the system like coherency, reliability, measurement fidelity, etc. In this considered potential, the decay rate from the penetrating (False vacuum) state to the stable (absolute minimum) state is achieved to leading order in Planck constant by the approach of Instanton model. In case of the superconducting flux qubit having thin barrier potential, the decay rate is calculated and its relations with actual set of parameters in flux qubit design are introduced.

Ali Izadi Rad; Hesam Zandi; Mehdi Fardmanesh

2014-11-26T23:59:59.000Z

397

THE SNS VACUUM CONTROL SYSTEM UPGRADE FOR THE SUPERCONDUCTING LINAC  

SciTech Connect

The superconducting linac of the Spallation Neutron Source (SNS) has 23 cryomodules whose vacuum system is monitored and controlled by custom built hardware. The original control hardware was provided by Thomas Jefferson National Accelerator Facility (JLab) and contained a variety of custom boards utilizing integrated circuits to perform logic. The need for control logic changes, a desire to increase maintainability, and a desire to increase flexibility to adapt for the future has led to a Programmable Logic Controller (PLC) based upgrade. This paper provides an overview of the commercial off-the-shelf (COTS) hardware being used in the superconducting vacuum control system. Details of the design and challenges to convert a control system during small windows of maintenance periods without disrupting beam operation will be covered in this paper.

Williams, Derrick C [ORNL] [ORNL

2009-01-01T23:59:59.000Z

398

Superconductivity in SrNi2P2 single crystals  

SciTech Connect

Heat capacity, magnetic susceptibility, and resistivity of SrNi{sub 2}P{sub 2} single crystals are presented, illustrating the structural transition at 325 K, and bulk superconductivity at 1.4 K. The magnitude of {Tc}, fits to the heat capacity data, the small upper critical field H{sub c2} = 390 Oe, and {kappa} = 2.1 suggests a conventional fully gapped superconductor. With applied pressure we find that superconductivity persists into the so-called 'collapsed tetragonal' phase, although the transition temperature is monotonically suppressed with increasing pressure. This argues that reduced dimensionality can be a mechanism for increasing the transition temperatures of layered NiP, as well as layered FeAs and NiAs, superconductors.

Ronning, Filip [Los Alamos National Laboratory; Bauer, Eric D [Los Alamos National Laboratory; Park, Tuscon [Los Alamos National Laboratory; Thompson, Joe D [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

399

Acoustic microscopy for characterization of high?temperature superconducting tape  

Science Journals Connector (OSTI)

Although material scientists constantly discover superconducting compounds with higher critical temperatures (T c ’s) manufacturing of the high?temperature superconductors(HTS) remains a problem and long lengths (>1 mile) have yet to be produced. In an effort to produce long length superconductors manufacturing steps for HTS tape production have been critically looked at to find their effects in producing tape with the desired characteristics. In support of determining superconducting tapecharacteristics acoustic microscopy offers the potential for internal microstructural material characterization. This research will ultimately support in?process monitoring of HTSmanufacturing as part of an advanced sensing system to determine the presence of defects and/or the effects of process variables on the HTS tape. This presentation will overview scanning acoustic microscopy and present images of HTS tape at several frequencies ranging from 50 to 500 MHz. The results clearly demonstrate the feasibility of determining the Ag/ceramic interface location and the general integrity of the constituents.

Chiaki Miyasaka; Chris Cobucci; Bernhard Tittmann

1997-01-01T23:59:59.000Z

400

Color Superconductivity in Compact Stars and Gamma Ray Bursts  

E-Print Network (OSTI)

We study the effects of color superconductivity on the structure and formation of compact stars. We show that it is possible to satisfy most of recent observational boundaries on masses and radii if a diquark condensate forms in a hybrid or a quark star. Moreover, we find that a huge amount of energy, of the order of $10^{53}$ erg, can be released in the conversion from a (metastable) hadronic star into a (stable) hybrid or quark star, if the presence of a color superconducting phase is taken into account. Accordingly to the scenario proposed in Astrophys.J.586(2003)1250, the energy released in this conversion can power a Gamma Ray Burst. This mechanism can explain the recent observations indicating a delay, of the order of days or years, between a few Supernova explosions and the subsequent Gamma Ray Burst.

A. Drago; A. Lavagno; G. Pagliara

2003-04-08T23:59:59.000Z

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


401

Spontaneous quenches of a high temperature superconducting pancake coil  

SciTech Connect

A double-pancake coil made of Bi-2223/Ag high temperature superconducting (HTS) tape was constructed with an embedded heater and graded conductors to study the stability and quench propagation in HTS coils. The experiments were performed with liquid nitrogen and gaseous helium cooling in temperatures ranging from 5 to 77 K. The coil was very stable, and no ``normal`` zone was sustained or propagated with local pulsed heating. However, spontaneous quenches of the cod were experienced. This was found to be the result of having the coil current higher than that of the lower I{sub c} sections of the coil for a long time. This quench process took minutes to develop--much longer than would be expected in a low temperature superconducting coil. The quench behaved more like a spreading and continuous heating of an increasingly larger partially resistive section of the coil than like a sequential ``normal`` front propagation.

Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States); Aized, D.; Campbell, J.M.; Schwall, R.E. [American Superconductor Corp., Westborough, MA (United States)

1995-09-01T23:59:59.000Z

402

Spontaneous quenches of a high temperature superconducting pancake coil  

SciTech Connect

A double-pancake coil made of Bi-2223/Ag high temperature superconducting (HTS) tape was constructed with an embedded heater and graded conductors to study the stability and quench propagation in HTS coils. The experiments were performed with liquid nitrogen and gaseous helium cooling in temperatures ranging from 5 to 77 K. The coil was very stable, and no normal zone was sustained or propagated with local pulsed heating. However, spontaneous quenches of the coil were experienced. This was found to be the result of having the coil current higher than that of the lower I{sub c} sections of the coil for a long time. This quench process took minutes to develop--much longer than would be expected in a low temperature superconducting coil. The quench behaved more like a spreading and continuous heating of an increasingly larger partially resistive section of the coil than like a sequential normal front propagation.

Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); Aized, D.; Campbell, J.M.; Schwall, R.E. [American Superconductor Corp., Westborough, MA (United States)] [American Superconductor Corp., Westborough, MA (United States)

1996-07-01T23:59:59.000Z

403

Fast Ferroelectric L-Band Tuner for Superconducting Cavities  

SciTech Connect

Design, analysis, and low-power tests are described on a ferroelectric tuner concept that could be used for controlling external coupling to RF cavities for the superconducting Energy Recovery Linac (ERL) in the electron cooler of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). The tuner configuration utilizes several small donut-shaped ferroelectric assemblies, which allow the design to be simpler and more flexible, as compared to previous designs. Design parameters for 704 and 1300 MHz versions of the tuner are given. Simulation results point to efficient performance that could reduce by a factor-of-ten the RF power levels required for driving superconducting cavities in the BNL ERL.

Jay L. Hirshfield

2012-07-03T23:59:59.000Z

404

Enhanced superconducting pairing interaction in indium-doped tin telluride  

SciTech Connect

The ferroelectric degenerate semiconductor Sn{sub 1-{delta}}Te exhibits superconductivity with critical temperatures, T{sub c}, of up to 0.3 K for hole densities of order 10{sup 21} cm{sup -3}. When doped on the tin site with greater than x{sub c} = 1.7(3)% indium atoms, however, superconductivity is observed up to 2 K, though the carrier density does not change significantly. We present specific heat data showing that a stronger pairing interaction is present for x > x{sub c} than for x < x{sub c}. By examining the effect of In dopant atoms on both T{sub c} and the temperature of the ferroelectric structural phase transition, T{sub SPT}, we show that phonon modes related to this transition are not responsible for this T{sub c} enhancement, and discuss a plausible candidate based on the unique properties of the indium impurities.

Erickson, A.S.

2010-05-03T23:59:59.000Z

405

Enhanced superconducting pairing interaction in indium-doped tin telluride  

SciTech Connect

The ferroelectric degenerate semiconductor Sn{sub 1-{delta}}Te exhibits superconductivity with critical temperatures, T{sub c}, of up to 0.3 K for hole densities of order 10{sup 21} cm{sup -3}. When doped on the tin site with greater than x{sub c} = 1.7(3)% indium atoms, however, superconductivity is observed up to 2 K, though the carrier density does not change significantly. We present specific heat data showing that a stronger pairing interaction is present for x > x{sub c} than for x < x{sub c}. By examining the effect of In dopant atoms on both T{sub c} and the temperature of the ferroelectric structural phase transition, T{sub SPT}, we show that phonon modes related to this transition are not responsible for this T{sub c} enhancement, and discuss a plausible candidate based on the unique properties of the indium impurities.

Erickson, A.S.; Chu, J.-H.; /Stanford U., Appl. Phys. Dept. /Stanford U., Geballe Lab.; Toney, M.F.; Geballe, T.H.; Fisher, I.R.; /SLAC, SSRL /Stanford U., Appl. Phys. Dept. /Stanford U., Geballe Lab.

2010-02-15T23:59:59.000Z

406

Method of manufacturing a niobium-aluminum-germanium superconductive material  

DOE Patents (OSTI)

A method for manufacturing flexible Nb.sub.3 (Al,Ge) multifilamentary superconductive material in which a sintered porous niobium compact is infiltrated with an aluminum-germanium alloy and thereafter deformed and heat treated in a series of steps at different successively higher temperatures preferably below 1000.degree. C. to produce filaments composed of Nb.sub.3 (Al,G3) within the compact. By avoiding temperatures in excess of 1000.degree. C. during the heat treatment, cladding material such as copper can be applied to facilitate a deformation step preceding the heat treatment and can remain in place through the heat treatment to also serve as a temperature stabilizer for supeconductive material produced. Further, these lower heat treatment temperatures favor formation of filaments with reduced grain size and, hence with more grain boundaries which in turn increase the current-carrying capacity of the superconductive material.

Wang, John L. (San Francisco, CA); Pickus, Milton R. (Oakland, CA); Douglas, Kent E. (Redondo Beach, CA)

1980-01-01T23:59:59.000Z

407

Superconductivity for Electric Systems: 2008 Annual Peer Review Final  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

for Electric Systems: 2008 Annual Peer Review for Electric Systems: 2008 Annual Peer Review Final Report Superconductivity for Electric Systems: 2008 Annual Peer Review Final Report The Office of Electricity Delivery and Energy Reliability's High Temperature Superconductivity (HTS) for Electric Systems Program's specific mission is to work in partnership with industry to develop HTS wire and perform other research and development activities leading to the commercialization of HTS-based electric power applications by U.S. companies. This technology contributes to several key performance improvements of the grid. It enhances reliability by increasing capacity, which relieves congestion and helps prevent outages. Efficiency is improved as a result of the reduction of loss during operation which both conserves

408

Project Fact Sheet Long Island HTS Power Cable Superconducting  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Long Long Island HTS Power Cable Superconducting Power Equipment www.oe.energy.gov Phone: 202-586-1411 Office of Electricity Delivery and Energy Reliability, OE-1 U.S. Department of Energy - 1000 Independence Avenue, SW - Washington, DC 20585 Plugging America Into the Future of Power What is the status of the Project? The cable was energized April 22, 2008 and serves the equivalent of 300,000 homes. It is the first HTS power cable to operate at transmission voltage in the grid. LIPA plans to retain the superconductor as a permanent part of it's grid. This project involves the demonstration of a high- temperature superconducting (HTS) power cable in the Long Island Power grid, spanning nearly half a mile and serving as a permanent link in the Long Island Power

409

Ensure Continuous Power to Critical Industrial Processes with the New Superconducting Storage Device (SSD™)  

E-Print Network (OSTI)

Administration system. In that project a superconducling coil was used to provide energy to stabilizc a transmission line. Sl's focus on the benefits of superconducting magnetic energy storage Figure I. SI cryostat in an SSO trailer. 63 ESL-IE-92... capacity, While superconducting magnets have bcen used for over 10 years for magnetic resonance imaging, the only previous use of superconductivity for power systems has been a research project in the early eightjes on the Bonneville Power...

Dewinkel, C. C.; Koeppe, P. F.

410

Antenna-coupled high T[sub c] superconducting microbolometer  

DOE Patents (OSTI)

A device is provided for measuring radiant energy, the device comprising a substrate; a bolometer formed from a high T[sub c] superconducting material disposed on the substrate in an area that is about 1[times]5 [mu]m[sup 2] and about 0.02 [mu]m in depth; and a planar antenna disposed on the substrate and coupled to receive radiation and to impart the received radiation to the bolometer. 5 figs.

Hu, Q.

1992-12-15T23:59:59.000Z

411

Ferrimagnetic Spin Wave Resonance and Superconductivity in Carbon Nanotubes  

E-Print Network (OSTI)

The phenomenon of ferrimagnetic spin wave resonance [uncompensated antiferromagnetic spin wave resonance] has been detected for the first time. It has been observed in carbon nanotubes, produced by high energy ion beam modification of diamond single crystals in $\\ $ direction. Peculiarities of spin wave resonance observed allow to insist on the formation in given nanotubes of $s^+$ superconductivity at room temperature, coexisting with uncompensated antiferromagnetic ordering.

Yerchuck, Dmitri; Stelmakh, Vyacheslav; Dovlatova, Alla; Alexandrov, Andrey

2013-01-01T23:59:59.000Z

412

SUPERCONDUCTING RING CYCLOTRON FOR RIKEN RI BEAM FACTORY IN JAPAN  

SciTech Connect

Since 1997, RIKEN Nishina Center has been constructing the Radioactive Isotope Beam Factory (RIBF) and succeeded in beam commissioning of its accelerator complex at the end of 2006. The world's first superconducting ring cyclotron (SRC) is the final booster in the RIBF accelerator complex which is able to accelerate all-element heavy ions to a speed of about 70% of the velocity of light. The ring cyclotron consists of 6 major superconducting sector magnets with a maximum field of 3.8 T. The total stored energy is 235 MJ, and its overall sizes are 19 m diameter, 8 m height and 8,300 tons. The magnet system assembly was completed in August 2005, and successfully reached the maximum field in November 2005. The first beam was extracted at the end of 2006 and the first uranium beam was extracted in March 2007. However operation of the helium refrigerator was not satisfactory although the commissioning of SRC was successful. Operation was stopped every two month due to degradation of its cooling power. In February 2008 the reason of the degradation was revealed to be oil contamination. Operation of the cryogenic system was restarted from August 2008 after hard task to clean up the helium refrigerator and to add oil separators to the compressor. After restoration long-term steady operation to keep the magnet superconducting continued for about 8 months with no sign of degradation of cooling capacity.

Okuno, H.; Dantsuka, T.; Yamada, K.; Kase, M.; Maie, T.; Kamigaito, O. [RIKEN Nishina Center, Wako, Saitama, 351-0198 (Japan)

2010-04-09T23:59:59.000Z

413

Design of a superconducting 20 MJ induction heating coil  

SciTech Connect

A pancake-wound, low-loss, superconducting, induction-heating coil has been designed to demonstrate the feasibility of superconducting polaidal system for the Tokamak reactors, to provide confidence in application of superconductivity to actual reactors, and to provide the opportunity to solve specific engineering problems to support the fusion pulsed coil program. the coil is designed to store 20 MJ at 50 kA. The superconductor material is NbTi for a 7.5 tesla maximum field. The coil is designed to survive at least 100,000 cycles of full bipolar half cycle sinusoidal operation from +7.5 tesla to -7.5 telsa fields in one second. The coil is natural convection immersion-cooled at 4.5/sup 0/K in liquid helium bath. The design demonstrates confidence in an advanced design, low-loss, cryostable conductor, along with safety, reliability and the operating life of the coil of more than 100,000 cycles.

Singh, S.K.; Ibrahim, E.A.; Gaberson, P.C.; Eckels, P.W.; Jarabak, A.J.; Rogers, J.D.; Thullen, P.; Walker, M.S.

1980-01-01T23:59:59.000Z

414

Superconducting hot-electron nanobolometer with microwave bias and readout  

E-Print Network (OSTI)

We propose a new detection technique based on radio-frequency (RF) bias and readout of an antenna-coupled superconducting nanobolometer. This approach is suitable for Frequency-Division-Multiplexing (FDM) readout of large arrays using broadband low-noise RF amplifier. We call this new detector RFTES. This feasibility study was made on demonstrator devices which are made in all-Nb technology and operate at 4.2 K. The studied RFTES devices consist of an antenna-coupled superconducting nanobolometer made of ultrathin niobium films with transition temperature Tc = 5.2 K. The 0.65-THz antenna and nanobolometer are embedded as a load into a GHz-range coplanar niobium resonator (Tc = 8.9 K, Q = 4000). To heat the superconducting Nb nanobolometer close to the Tc, the RF power at resonator frequency f = 5.8 GHz is applied via a transmission line which is weakly coupled (-11 dB) to the loaded resonator. The THz-antenna of RFTES was placed in the focus of a sapphire immersion lens inside a He4-cryostat equipped with an ...

Kuzmin, A A; Shitov, S V; Abramov, N N; Ermakov, A B; Arndt, M; Wuensch, S H; Ilin, K S; Ustinov, A V; Siegel, M

2014-01-01T23:59:59.000Z

415

Audit of controls over Superconducting Super Collider Laboratory subcontractor expenditures  

SciTech Connect

In January 1989 the Department of Energy contracted with Universities Research Association, Inc. to design, construct, manage, operate, and maintain the Superconducting Super Collider Laboratory. Through Fiscal Year 1992, costs for subcontractor goods and services accounted for about 75 percent of the Superconducting Super Collider Laboratory expenditures. The Office of Inspector General evaluated the adequacy of controls in place to ensure that subcontractor costs were reasonable, as required by the contract. The following conclusions were drawn from the audit. The Superconducting Super Collider Laboratory did not consistently exercise prudent business judgment in making subcontractor expenditures. As a result, $60 million in expenditures already made and $128 million planned with commercial subcontractors were, in the authors opinion, unnecessary, excessive, or represented uncontrolled growth. The audit also found inadequate justifications, accountability, and cost controls over $143 million in expenditures made and $47 million planned with other Department of Energy laboratories. Improvements were needed in subcontract administration and internal controls, including appropriate audit coverage of the subcontracts. In addition, Department of Energy guidance concerning procurement actions between the laboratories needed to be established.

Not Available

1993-10-22T23:59:59.000Z

416

Excitonic absorption and superconductivity in YBa2Cu3O7-y  

Science Journals Connector (OSTI)

Optical and neutron-diffraction studies of superconducting and nonsuperconducting samples of YBa2Cu3O7-y are described. Superconducting samples, with y?0.1, showed two strong electronic transitions, at 3000 cm-1/0.37 eV and at 20 000 cm-1/2.5 eV, which are interpreted as charge-transfer bands (i.e., excitons). Nonsuperconducting samples, with y?0.8 (prepared by heating of superconducting samples in vacuum to deplete the oxygen content), did not show these features. Our measurements support an excitonic mechanism for the superconductivity in high-Tc copper oxide compounds.

K. Kamarás, C. D. Porter, M. G. Doss, S. L. Herr, and D. B. Tanner, D. A. Bonn, J. E. Greedan, A. H. O’Reilly, C. V. Stager, and T. Timusk

1987-08-24T23:59:59.000Z

417

E-Print Network 3.0 - ag-clad bi-based superconducting Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Dependencies of Summary: of Bi-based high-temperature superconducting tapes," Physical Review B, vol. 45, pp. 2545-2548, 1992. 7... 2840 IEEE TRANSACTIONS ON APPLIED...

418

E-Print Network 3.0 - astromag superconducting magnet Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

superconducting cuprates have the capability to pass very high currents in magnetic fields well above the highest... DC field in the world, the 45 tesla hybrid magnet (a ......

419

Second generation high-temperature superconducting solenoid coils and energy storage.  

E-Print Network (OSTI)

??One of the most promising applications of superconductors is in Superconducting Magnetic Energy Storage (SMES) systems, which are becoming the enabling engines for improving the… (more)

Baiej, Hanan Tahir

2013-01-01T23:59:59.000Z

420

Proceedings of the fourth international conference and exhibition: World Congress on superconductivity. Volume 1  

SciTech Connect

The goals of the World Congress on Superconductivity (WCS) have been to establish and foster the development and commercial application of superconductivity technology on a global scale by providing a non-adversarial, non-advocacy forum where scientists, engineers, businessmen and government personnel can freely exchange information and ideas on recent developments and directions for the future of superconductive research. Sessions were held on: accelerator technology, power and energy, persistent magnetic fields, performance characterization, physical properties, fabrication methodology, superconductive magnetic energy storage (SMES), thin films, high temperature materials, device applications, wire fabrication, and granular superconductors. Individual papers are indexed separately.

Krishen, K.; Burnham, C. [eds.] [National Aeronautics and Space Administration, Houston, TX (United States). Lyndon B. Johnson Space Center

1994-12-31T23:59:59.000Z

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


421

E-Print Network 3.0 - argonne superconducting linac Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

ANL Argonne National Laboratory ANSI American National... superconducting undulator HVAC heating, ventilating, and air conditioning IBS intra-beam scattering ID inner......

422

Proceedings of the sixth Japan--US workshop on high-field superconducting materials and standard procedures for high-field superconducting materials testing  

SciTech Connect

High critical current densities and high magnetic fields are needed for most important energy application of both conventional and high-Tc superconductors. This workshop brought together those engaged research on high-field superconductors in Japan and the US to present recent research results on performance of new high-field superconducting materials and to discuss the most promising directions for research, specifically as it relates to the fusion energy needs of both countries. Topics covered included critical currents, irradiation effects, ac losses, magnetization properties, and new fabrication processes for conventional superconductors. An entire session was devoted to presentations on the properties of Nb{sub 3}Al superconductors. Large magnet research programs for energy applications were reviewed, including the tokamak fusion machine at JAERI, the joint US-Japan Nb{sub 3}Sn poloidal-field-coll development program, and the proposed International Thermonuclear Experimental Reactor (ITER) project. Results were also presented on the VAMAS round robin in three areas; J{sub c}, stress effects, and ac losses. Finally, some current research results on experimental high-{Tc} superconductors were reviewed, with particular emphasis on new fabrication processes and the factors limiting the critical current in high-current conductors. Separate abstracts have been prepared.

Tachikawa, K. [ed.] [Tokai Univ., Kanagawa (Japan). Faculty of Engineering; Yamafuji, K. [ed.] [Kyushu Univ., Fukuoka (Japan). Dept. of Electronics; Wada, H. [ed.] [National Research Inst. for Metals, Tsukuba, Ibaraki (Japan); Ekin, J.W. [ed.] [National Inst. of Standards and Technology, Boulder, CO (United States); Suenaga, M. [ed.] [Brookhaven National Lab., Upton, NY (United States)

1989-12-31T23:59:59.000Z

423

Proceedings of the sixth Japan--US workshop on high-field superconducting materials and standard procedures for high-field superconducting materials testing  

SciTech Connect

High critical current densities and high magnetic fields are needed for most important energy application of both conventional and high-Tc superconductors. This workshop brought together those engaged research on high-field superconductors in Japan and the US to present recent research results on performance of new high-field superconducting materials and to discuss the most promising directions for research, specifically as it relates to the fusion energy needs of both countries. Topics covered included critical currents, irradiation effects, ac losses, magnetization properties, and new fabrication processes for conventional superconductors. An entire session was devoted to presentations on the properties of Nb[sub 3]Al superconductors. Large magnet research programs for energy applications were reviewed, including the tokamak fusion machine at JAERI, the joint US-Japan Nb[sub 3]Sn poloidal-field-coll development program, and the proposed International Thermonuclear Experimental Reactor (ITER) project. Results were also presented on the VAMAS round robin in three areas; J[sub c], stress effects, and ac losses. Finally, some current research results on experimental high-[Tc] superconductors were reviewed, with particular emphasis on new fabrication processes and the factors limiting the critical current in high-current conductors. Separate abstracts have been prepared.

Tachikawa, K. (ed.) (Tokai Univ., Kanagawa (Japan). Faculty of Engineering); Yamafuji, K. (ed.) (Kyushu Univ., Fukuoka (Japan). Dept. of Electronics); Wada, H. (ed.) (National Research Inst. for Metals, Tsukuba, Ibaraki (Japan)); Ekin, J.W. (ed.) (National Inst. of Standards and Technology, Boulder, CO (United States)); Suenaga, M. (ed.) (Brookhaven National Lab., Upton, NY (United States))

1989-01-01T23:59:59.000Z

424

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

41 - 21750 of 28,905 results. 41 - 21750 of 28,905 results. Download Slide 1 http://energy.gov/management/downloads/slide-1-10 Download No Slide Title http://energy.gov/management/downloads/no-slide-title-2 Download Before the Senate Environment and Public Works Committee Subject: Domestic Renewable Fuels By: Henry Kelly, Acting Assistant Secretary Office of Energy Efficiency and Renewable Energy http://energy.gov/congressional/downloads/senate-environment-and-public-works-committee-0 Download Information Concerning Reliability Impacts under Various System Configurations of the Mirant Potomac River Plant http://energy.gov/oe/downloads/information-concerning-reliability-impacts-under-various-system-configurations-mirant Download Fault Current Limiters (FCL) Fact Sheet Plugging America Into the Future of Power: Superconducting & Solid-state

425

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

31 - 3840 of 8,172 results. 31 - 3840 of 8,172 results. Download CX-003065: Categorical Exclusion Determination Clean Energy Property Rebate Program - Southeast Office Partners, LLC Lighting Retrofit CX(s) Applied: A9, B5.1 Date: 07/16/2010 Location(s): Tucker, Georgia Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-003065-categorical-exclusion-determination Download CX-003061: Categorical Exclusion Determination Recovery Act-Fault Current Limiting (FCL) Superconducting Transformer CX(s) Applied: A9, B3.6, B4.11 Date: 07/16/2010 Location(s): Irvine, California Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-003061-categorical-exclusion-determination

426

Categorical Exclusion Determinations: A9 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

6, 2010 6, 2010 CX-003112: Categorical Exclusion Determination Large-Scale Wind Training Program CX(s) Applied: A9 Date: 07/16/2010 Location(s): New York Office(s): Energy Efficiency and Renewable Energy, Golden Field Office July 16, 2010 CX-003061: Categorical Exclusion Determination Recovery Act-Fault Current Limiting (FCL) Superconducting Transformer CX(s) Applied: A9, B3.6, B4.11 Date: 07/16/2010 Location(s): Irvine, California Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory July 16, 2010 CX-003065: Categorical Exclusion Determination Clean Energy Property Rebate Program - Southeast Office Partners, LLC Lighting Retrofit CX(s) Applied: A9, B5.1 Date: 07/16/2010 Location(s): Tucker, Georgia Office(s): Energy Efficiency and Renewable Energy, National Energy

427

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

61 - 10770 of 26,764 results. 61 - 10770 of 26,764 results. Download CX-003065: Categorical Exclusion Determination Clean Energy Property Rebate Program - Southeast Office Partners, LLC Lighting Retrofit CX(s) Applied: A9, B5.1 Date: 07/16/2010 Location(s): Tucker, Georgia Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-003065-categorical-exclusion-determination Download CX-003061: Categorical Exclusion Determination Recovery Act-Fault Current Limiting (FCL) Superconducting Transformer CX(s) Applied: A9, B3.6, B4.11 Date: 07/16/2010 Location(s): Irvine, California Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-003061-categorical-exclusion-determination

428

A "permanent" high-temperature superconducting magnet operated in thermal communication with a mass of solid nitrogen  

E-Print Network (OSTI)

This thesis explores a new design for a portable "permanent" superconducting magnet system. The design is an alternative to permanent low-temperature superconducting (LTS) magnet systems where the magnet is cooled by a ...

Haid, Benjamin J. (Benjamin John Jerome), 1974-

2001-01-01T23:59:59.000Z

429

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

E-Print Network (OSTI)

SQUIDs) from high-temperature superconductors such as YBCOsuperconductors. However, the thermal noise inform the increased operating temperature os high-high-temperature superconductivity, Josephson junctions, electron beam lithography I. I NTRODUCTION Superconducting interference devices (SQUIDs) from conventional superconductors

Roediger, Peter

2014-01-01T23:59:59.000Z

430

Novel ASTA Users Facility At Fermilab: A Testbed For Superconducting RF Technology And ERL R&D  

E-Print Network (OSTI)

The Advanced Superconducting Test Accelerator (ASTA) currently under commissioning at Fermilab will enable a broad range of beam-based experiments to study fundamental limitations to beam intensity and to develop transformative approaches to particle-beam generation, acceleration and manipulation. ASTA incorporates a superconducting radiofrequency (SRF) linac coupled to a photoinjector and small-circumference storage ring capable of storing electrons or protons. ASTA will establish a unique resource for R&D towards Energy Frontier facilities and a test-bed for SRF accelerators and high-brightness beam applications, including ERLs. The unique features of ASTA include: (1) a high repetition-rate, (2) one of the highest peak and average brightness within the U.S., (3) a GeV-scale beam energy, (4) an extremely stable beam, (5) the availability of SRF and high quality beams together, and (6) a storage ring capable of supporting a broad range of ring-based advanced beam dynamics experiments. These unique featur...

Shiltsev, V

2014-01-01T23:59:59.000Z

431

Smart Materials Based System Operated at 2K Used as a Superconducting Cavity Tuner for VUV-fel Purpose  

E-Print Network (OSTI)

Smart Materials Based System Operated at 2K Used as a Superconducting Cavity Tuner for VUV-fel Purpose

Sekalski, P; Simrock, S; Albrecht, C; Lilje, L; Bosland, P; Fouaidy, M; Bosotti, A; Paparella, R

2006-01-01T23:59:59.000Z

432

Nb-Pb superconducting RF-gun TESLA-FEL Report 2005-09  

E-Print Network (OSTI)

Nb-Pb superconducting RF-gun TESLA-FEL Report 2005-09 J. Sekutowicz, J. Iversen, G. Kreps, W Sand Hill Road, Menlo Park, CA 94025, USA We report on the status of an electron RF-gun made of two superconducting RF-gun as it has been proposed by the BNL group. Measured values of quantum efficiency for lead

433

Superconductivity and Physical Properties of CaPd2Ge2 Single Crystals  

SciTech Connect

We present the superconducting and normal state properties of CaPd2Ge2 single crystals investigated by magnetic susceptibility ?, isothermal magnetization M, heat capacity Cp, in-plane electrical resistivity ? and London penetration depth ? versus temperature T and magnetic field H measurements. Bulk superconductivity is inferred from the ?(T) and Cp(T) data. The ?(T) data exhibit metallic behavior and a superconducting transition with Tc onset = 1.98 K and zero resistivity at Tc 0 = 1.67 K. The ?(T) reveals the onset of superconductivity at 2.0 K. For T > 2.0 K, the ?(T) and M(H) are weakly anisotropic paramagnetic with ?ab > ?c. The Cp(T) data confirm the bulk superconductivity below Tc = 1.69(3) K. The superconducting state electronic heat capacity is analyzed within the framework of a single-band ?-model of BCS superconductivity and various normal and superconducting state parameters are estimated. Within the ?-model, the Cp(T) data and the ab plane ?(T) data consistently indicate a moderately anisotropic s-wave gap with ?(0)/kBTc ? 1.6, somewhat smaller than the BCS value of 1.764. The relationship of the heat capacity jump at Tc and the penetration depth measurement to the anisotropy in the s-wave gap is discussed.

Anand, V K [Ames Laboratory; Kim, Hyunsoo [Ames Laboratory; Tanatar, Makariy A [Ames Laboratory; Prozorov, Ruslan [Ames Laboratory; Johnston, David C [Ames Laboratory

2014-10-08T23:59:59.000Z

434

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

E-Print Network (OSTI)

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

Boyer, Edmond

435

ensl-00109517,version1-24Oct2006 Superconducting instability in 3 bands metallic nanotubes  

E-Print Network (OSTI)

ensl-00109517,version1-24Oct2006 Superconducting instability in 3 bands metallic nanotubes David on small radius nanotubes, we study the superconducting in- stabilities of cylindrical (5,0) nanotubes. According to band structure calculations, these nanotubes possess three bands at the Fermi energy. Using

436

Superconductivity for Electric Systems Program Review LANL Contributions to GE HTS Generator  

E-Print Network (OSTI)

-section · Develop a heat generation profile => thermal analysis #12;Superconductivity for Electric Systems Program of coolant loop to verify heat due to flow work on helium #12;Superconductivity for Electric Systems Program for Electric Systems Program Review Stationary heat pipe tests were necessary to determine performance impact

437

Use of Superconducting Magnet Technology for Astronaut Radiation Protection PI: Jeffery Hoffman, MIT  

E-Print Network (OSTI)

Use of Superconducting Magnet Technology for Astronaut Radiation Protection PI: Jeffery Hoffman of radiation from cosmic rays. The proposed superconducting magnetic radiation shielding system could a conceptual systems design. In Phase II, we plan to extend the shielding studies to a detailed comparison

Shepherd, Simon

438

High-Temperature Superconducting Cable Testing Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network (OSTI)

High-Temperature Superconducting Cable Testing Gregory S. Boebinger, National High Magnetic Field-Temperature Superconducting (HTS) Cables are desirable for application in large high-field magnets (>20 T), especially when). Of the three HTS magnet cable concepts emerging, the Conductor On Round Core was the first that was tested

Weston, Ken

439

Superconducting Cables for a.c. and d.c. Power Transmission  

Science Journals Connector (OSTI)

...1973 research-article Superconducting Cables for a.c. and d.c. Power Transmission...power transmission lines. Some present cables are water cooled to increase their current...both a.c. and d.c. superconducting cables are described, with particular attention...

1973-01-01T23:59:59.000Z

440

Low-Cost Superconducting Wire for Wind Generators: High Performance, Low Cost Superconducting Wires and Coils for High Power Wind Generators  

SciTech Connect

REACT Project: The University of Houston will develop a low-cost, high-current 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. The University of Houston’s innovation is based on engineering nanoscale defects in the superconducting film. This could quadruple the current relative to today’s superconducting wires, supporting the same amount of current using 25% of the material. This would make wind generators lighter, more powerful and more efficient. The design could result in a several-fold reduction in wire costs and enable their commercial viability of high-power wind generators for use in offshore applications.

None

2012-01-01T23:59:59.000Z

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


441

FED pumped limiter configuration issues  

SciTech Connect

Impurity control in the Fusion Engineering Device (FED) is provided by a toroidal belt pumped limiter. Limiter design issues addressed in this paper are (1) poloidal location of the limiter belt, (2) shape of the limiter surface facing the plasma, and (3) whether the belt is pumped from one or both sides. The criteria used for evaluation of limiter configuration features were sensitivity to plasma-edge conditions and ease of maintenance and fabrication. The evaluation resulted in the selection of a baseline FED limiter that is located at the bottom of the device and has a flat surface with a single leading edge.

Haines, J.R.; Fuller, G.M.

1983-01-01T23:59:59.000Z

442

Structure and superconductivity of isotope-enriched boron-doped diamond  

SciTech Connect

Superconducting boron-doped diamond samples were synthesized with isotopes of {sup 10}B, {sup 11}B, {sup 13}C and {sup 12}C. We claim the presence of a carbon isotope effect on the superconducting transition temperature, which supports the 'diamond-carbon'-related nature of superconductivity and the importance of the electron-phonon interaction as the mechanism of superconductivity in diamond. Isotope substitution permits us to relate almost all bands in the Raman spectra of heavily boron-doped diamond to the vibrations of carbon atoms. The 500 cm{sup 01} Raman band shifts with either carbon or boron isotope substitution and may be associated with vibrations of paired or clustered boron. The absence of a superconducting transition (down to 1.6 K) in diamonds synthesized in the Co-C-B system at 1900 K correlates with the small boron concentration deduced from lattice parameters.

Thompson, Joe D [Los Alamos National Laboratory; Ekimov, E A [INSTIT OF HIGH PRESSURE; Sidorov, V A [INSTIT OF HIGH PRESSURE; Zoteev, A [MOSCOW SU; Lebed, Y [INST FOR NUCI RES; Stishov, S M [INST FOR HIGH PRESSURE

2008-01-01T23:59:59.000Z

443

Modified magnetism within the coherence volume of superconducting FeSeTe  

SciTech Connect

Neutron Scattering is used to probe magnetic interactions as superconductivity develops in opti- mally doped Fe_(1+ )Se_xTe_(1 x). Applying the first moment sum-rule to comprehensive neutron scatter- ing data, we extract the change in magnetic exchange energy [J_(R-R ) S_R S_R ] in the superconducting state referenced to the normal state. Oscillatory changes are observed for Fe-Fe displacements | R| < , where = 1.3(1) nm is the superconducting coherence length. Dominated by a large reduction in the second nearest neighbor exchange energy (-1.2(2) meV/Fe), the overall reduction in magnetic interaction energy is Hmag = 0.31(9) meV/Fe. Comparison to the superconducting condensation energy E_sc = 0.013(1) meV/Fe, which we extract from specific heat data, suggests the modified magnetism we probe drives superconductivity in Fe_(1+ )Se_xTe_(1 x)

Leiner, Jonathan C [ORNL; Thampy, Vivek [ORNL; Christianson, Andrew D [ORNL; Abernathy, D. [Oak Ridge National Laboratory (ORNL); Stone, Matthew B [ORNL; Lumsden, Mark D [ORNL; Sales, Brian C [ORNL; Safa-Sefat, Athena [ORNL; Hu, Jin [Tulane University; Mao, Zhiqiang [Tulane University; Bao, Wei [Renmin University of China; Broholm, Collin L [ORNL

2014-01-01T23:59:59.000Z

444

Control Surveys for Underground Construction of the Superconducting Super Collider  

SciTech Connect

Particular care had to be taken in the design and implementation of the geodetic control systems for the Superconducting Super Collider (SSC) due to stringent accuracy requirements, the demanding tunneling schedule, long duration and large size of the construction effort of the project. The surveying requirements and the design and implementation of the surface and underground control scheme for the precise location of facilities which include approximately 120 km of bored tunnel are discussed. The methodology used for the densification of the surface control networks, the technique used for the transfer of horizontal and vertical control into the underground facilities, and the control traverse scheme employed in the tunnels is described.

Greening, W.J.Trevor; Robinson, Gregory L.; /Measurment Science Inc.; Robbins, Jeffrey S.; Ruland, Robert E.; /SLAC

2005-08-16T23:59:59.000Z

445

Superconducting RF Lab Facility Upgrades at Los Alamos  

SciTech Connect

Research and testing of multi-cell superconducting cavities demands extensive contamination control resources to achieve high-cavity fields. Facility upgrades at Los Alamos National Laboratory (LANL) included the modernization of test equipment, expanding and modernizing cleanroom facilities, improving safety, and expanding the high-pressure rinse cleaning process equipment. Each upgrade was integrated into the facility to enable users to assemble prototype cryomodules. The scope of the upgrades, the new installed capability, and budget and schedule for certain aspects of the project are discussed in this paper.

Katonak, D.J.; Rusnak, B.

1999-03-01T23:59:59.000Z

446

Optimised quantum hacking of superconducting nanowire single-photon detectors  

E-Print Network (OSTI)

We explore bright-light control of superconducting nanowire single-photon detectors (SNSPDs) in the shunted configuration (a practical measure to avoid latching). In an experiment, we simulate an illumination pattern the SNSPD would receive in a typical quantum key distribution system under hacking attack. We show that it effectively blinds and controls the SNSPD. The transient blinding illumination lasts for a fraction of a microsecond and produces several deterministic fake clicks during this time. This attack does not lead to elevated timing jitter in the spoofed output pulse, and hence does not introduce significant errors. Five different SNSPD chip designs were tested. We consider possible countermeasures to this attack.

Michael G. Tanner; Vadim Makarov; Robert H. Hadfield

2013-05-26T23:59:59.000Z

447

Optimised quantum hacking of superconducting nanowire single-photon detectors  

E-Print Network (OSTI)

We explore optimised control of superconducting nanowire single-photon detectors (SNSPDs) through bright illumination. We consider the behaviour of the SNSPD in the shunted configuration (a practical measure to avoid latching) in long-running quantum key distribution experiments. We propose and demonstrate an effective bright-light attack on this realistic configuration, by applying transient blinding illumination lasting for a fraction of a microsecond and producing several deterministic fake clicks during this time. We show that this attack does not lead to elevated timing jitter in the spoofed output pulse, and is hence not introducing significant errors. Five different SNSPD chip designs were tested. We consider possible countermeasures to this attack.

Tanner, Michael G; Hadfield, Robert H

2013-01-01T23:59:59.000Z

448

Anomalous Finite-Size Effect in Superconducting Josephson Junction Arrays  

SciTech Connect

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

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

2001-08-06T23:59:59.000Z

449

Construction of the CERN Fast Cycled Superconducting Dipole Magnet Prototype  

E-Print Network (OSTI)

CERN is pursuing a small scale R&D on a fast cycled superconducting dipole magnet (FCM) of interest for the upgrade plan of the LHC accelerator complex. The FCM dipole prototype being built has a number of novel features if compared to other magnets for similar applications. In this paper we describe the magnet design, and its expected performance, focusing especially on the novel features (magnetic circuit, mechanical supports, cooling) and on the details of the manufacturing procedure (coil winding and impregnation, joints, instrumentation and quench protection).

Borgnolutti, F; Bottura, L; Carra, F; Foffano, G; Gomes De Faria, J M; Kalouguine, O; Kirby, G; Lopez, C; Tommasini, D

2012-01-01T23:59:59.000Z

450

Energy of magnetic moment of superconducting current in magnetic field  

E-Print Network (OSTI)

The energy of magnetic moment of the persistent current circulating in superconducting loop in an externally produced magnetic field is not taken into account in the theory of quantization effects because of identification of the Hamiltonian with the energy. This identification misleads if, in accordance with the conservation law, the energy of a state is the energy expended for its creation. The energy of magnetic moment is deduced from a creation history of the current state in magnetic field both in the classical and quantum case. But taking this energy into account demolishes the agreement between theory and experiment. Impartial consideration of this problem discovers the contradiction both in theory and experiment.

V. L. Gurtovoi; A. V. Nikulov

2014-12-22T23:59:59.000Z

451

Anisotropic transport properties of ferromagnetic-superconducting bilayers  

E-Print Network (OSTI)

magnetization per unit area of the FM film is m and its width is L. The energy necessary to create a single Pearl vortex10 in the superconductor is ev05e0ln(l/j) with e05f02/16p2l , where f0 is the flux quantum, l5lL2 /ds is the effective penetration depth...,11 lL5Amec2/4pnse2 is the London penetration depth, ds is the thickness of the super- conducting layer, and j is its coherence length. It was shown in Ref. 7 that the interaction between the superconducting vortices and the magnetization...

Kayali, MA; Pokrovsky, Valery L.

2004-01-01T23:59:59.000Z

452

Microelectronic superconducting device with multi-layer contact  

DOE Patents (OSTI)

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. The photolithographic process is used to separately pattern the high T[sub c] superconductor thin films. 14 figures.

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

1993-10-26T23:59:59.000Z

453

Superconducting gravity gradiometers for underground target recognition. Final report  

SciTech Connect

One of the most formidable intelligence challenges existing in the non-proliferation community is the detection of buried targets. The physical parameter that all buried targets share, whether the target is buried armaments, a tunnel or a bunker, is mass. In the case of buried armaments, there is an excess mass (higher density) compared to the surrounding area; for a tunnel or bunker, the mass is missing. In either case, this difference in mass generates a distinct gravitational signature. The Superconducting Gravity Gradiometer project at Sandia worked toward developing an airborne device for the detection of these underground structures.

Adriaans, M.J.

1998-01-01T23:59:59.000Z

454

Method for fabricating multi-strand superconducting cable  

DOE Patents (OSTI)

Multi-strand superconducting cables adapted to be used, for example, to wind a magnet are fabricated by directing wire strands inwardly from spools disposed on the perimeter of a rotating disk and wrapping them diagonally around a tapered mandrel with a flattened cross-sectional shape with a core having a wedge-shaped channel. As the cable is pulled axially, flexibly coupled wedge-shaped pieces are continuously passed through the channel in the mandrel and inserted into the cable as an internal support therefor.

Borden, A.R.

1985-04-01T23:59:59.000Z

455

Spontaneous vortex phase and pinning in ferromagnetic-superconducting systems  

E-Print Network (OSTI)

of epsilon10 as a function of rho0lambda for the case when n = 1, lambdaxi = 10,R1 = lambda,R2 = 2lambda and deltam = 10. . . . . . . . . . . . . . . 31 ix FIGURE Page 12 A superconducting thin film pierced by a ferromagnetic nano rod of radius R, length L... circle of radius rho0 that depends on the radii and magnetization per unit area of the annulus, and on the SC pene- tration depth lambda. In section five I focus on pinning and spontaneous vortex creation by a ferromagnetic rod which penetrates...

Kayali, Mohammad Amin

2004-09-30T23:59:59.000Z

456

Cyrogenic testing of 100 m superconducting power transmission test facility  

SciTech Connect

This follow-up study to the 1980 tests of a three-expander configuration are the final tests of the cryogenic system designed to cool the facility for testing 100 m superconducting power transmission cables. The system was modified to incorporate a fourth turbo expander remote from the refrigerator at the far end of the load. The system is described with a flow schematic. The tests performed and their results are presented with turbine operating conditions presented in a table. Summary and conclusions are followed by a discussion concerning the thermometry used on the cable and the + or - 10 mK accuracy quoted.

Gibbs, R.J.; Jensen, J.E.; Thomas, R.A.

1982-01-01T23:59:59.000Z

457

Process for producing Nb/sub 3/Sn superconducting wires  

SciTech Connect

A process for producing a Nb/sub 3/Sn superconducting wire, which comprises preparing a composite from a copper alloy material containing 0.1 to 5 atomic percent in total of at least one element of Group IV of the periodic table selected from titanium, zirconium and hafnium, a tin material and a niobium material, processing the composite into a wire, tape or tube, and heat-treating the processed composite at a temperature of 400/sup 0/ to 900/sup 0/ C. to form a Nb/sub 3/Sn compound.

Tachikawa, K.; Yoshida, S.

1984-03-06T23:59:59.000Z

458

Possible superconductivity in nearly antiferromagnetic itinerant fermion systems  

SciTech Connect

Strong spin fluctuations arising in itinerant fermion systems close to a magnetic instability may induce or inhibit superconductivity depending on the nesting wave vector q/sub 0/ for which the instability occurs. If chemically bondq/sub 0/chemically bond is small but finite, triplet pairing is favored and singlet pairing is suppressed as efficiently as in nearly ferromagnetic systems (q/sub 0/ = 0). If chemically bondq/sub 0/chemically bond is large, there is a repulsive contribution from backward scattering by which triplet as well as singlet pairings are strongly depressed. The cases of UPt/sub 3/, CePb/sub 3/, and some organic compounds are considered.

Beal-Monod, M.T.; Bourbonnais, C.; Emery, V.J.

1986-12-01T23:59:59.000Z

459

Alliance fights limits on chlorofluorocarbons  

Science Journals Connector (OSTI)

Alliance fights limits on chlorofluorocarbons ... Efforts by the nascent Alliance for Responsible CFC Policy to curb the Environmental Protection Agency's plans to put more limits on chlorofluorocarbons are beginning to have results. ... The 400-member alliance was formed last August to fight EPA's avowed intention to limit production of CFC's in the U.S. to 30% of their present levels. ...

1981-03-02T23:59:59.000Z

460

Effect of superfluid helium at the inner coil face on cooling and stability in superconducting accelerator magnets  

Science Journals Connector (OSTI)

For the upcoming luminosity upgrade of CERN's Large Hadron Collider a main issue is to increase the effective heat removal from the superconducting cables in the final focusing quadrupole magnets. The focus here is on the effect of superfluid helium in the thin annular space between the windings and the beam pipe which is studied using finite element modeling. Below the lambda temperature the effect of helium is described by an effective thermal conductivity. The temperature distribution is strongly dependent on the heat flux and therefore on the dimensions of the cooling channels and the spatial distribution of the heat source. Especially the influence of the so-called ground-insulation flaps partly blocking helium flow in the annulus is of interest. For a high energy deposition the flaps are a limiting factor. A solution is to implement a corrugated edged flap such that openings exist while sufficient electrical insulation is maintained.

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "limiting fcl superconducting" from the National Library of EnergyBeta (NLEBeta).
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461

Evidence for a resonant cyclotron interaction between runaway electrons and MHD modes in the experimental advanced superconducting tokamak  

SciTech Connect

In the past, the resonant cyclotron interaction between runaway electrons and lower hybrid waves via anomalous Doppler broadening was experimentally investigated, and it was shown to be able to create a barrier to the energy that could be reached by the runaway electrons [E. Li et al., Nucl. Instrum. Methods Phys. Res. A 621, 566 (2010)]. In this paper, to our knowledge for the first time, experimental evidence will be provided for a resonant cyclotron interaction between runaway electrons and magnetohydrodynamics modes in a stochastic magnetic field in the experimental advanced superconducting tokamak (EAST), which has been theoretically proposed as a mechanism able to limit the maximum attainable energy by runaway electrons in tokamak plasmas [J. R. Martin-Solis and R. Sanchez, Phys. Plasmas 15, 112505 (2008)].

Li Erzhong; Zhou Ruijie; Hu Liqun [Institute of Plasma Physics, Chinese Academy of Science, Hefei 230031 (China)

2011-09-15T23:59:59.000Z

462

New superconducting toroidal magnet system for IAXO, the international AXion observatory  

SciTech Connect

Axions are hypothetical particles that were postulated to solve one of the puzzles arising in the standard model of particle physics, namely the strong CP (Charge conjugation and Parity) problem. The new International AXion Observatory (IAXO) will incorporate the most promising solar axions detector to date, which is designed to enhance the sensitivity to the axion-photon coupling by one order of magnitude beyond the limits of the current state-of-the-art detector, the CERN Axion Solar Telescope (CAST). The IAXO detector relies on a high-magnetic field distributed over a very large volume to convert solar axions into X-ray photons. Inspired by the successful realization of the ATLAS barrel and end-cap toroids, a very large superconducting toroid is currently designed at CERN to provide the required magnetic field. This toroid will comprise eight, one meter wide and twenty one meter long, racetrack coils. The system is sized 5.2 m in diameter and 25 m in length. Its peak magnetic field is 5.4 T with a stored energy of 500 MJ. The magnetic field optimization process to arrive at maximum detector yield is described. In addition, materials selection and their structure and sizing has been determined by force and stress calculations. Thermal loads are estimated to size the necessary cryogenic power and the concept of a forced flow supercritical helium based cryogenic system is given. A quench simulation confirmed the quench protection scheme.

Shilon, I.; Dudarev, A.; Silva, H.; Wagner, U.; Kate, H. H. J. ten [European Organization for Nuclear Research (CERN), CH-1211, Genève 23 (Switzerland)

2014-01-29T23:59:59.000Z

463

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

E-Print Network (OSTI)

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

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

2014-04-02T23:59:59.000Z

464

Mitigating Radiation Impact on Superconducting Magnets of the Higgs Factory Muon Collider  

E-Print Network (OSTI)

Recent discovery of a Higgs boson boosted interest in a low-energy medium-luminosity Muon Collider as a Higgs Factory (HF). A preliminary design of the HF storage ring (SR) is based on cos-theta Nb3Sn superconducting (SC) magnets with the coil inner diameter ranging from 50 cm in the interaction region to 16 cm in the arc. The coil cross-sections were chosen based on the operation margin, field quality and quench protection considerations to provide an adequate space for the beam pipe, helium channel and inner absorber (liner). With the 62.5-GeV muon energy and 2 x 10^12 muons per bunch, the electrons from muon decays deposit about 300 kW in the SC magnets, or unprecedented 1 kW/m dynamic heat load, which corresponds to a multi-MW room temperature equivalent. Based on the detailed MARS15 model built and intense simulations, a sophisticated protection system was designed for the entire SR to bring the peak power density in the SC coils safely below the quench limit and reduce the dynamic heat load to the cold ...

Mokhov, Nikolai; Kashikhin, Vadim V; Striganov, Sergei I; Tropin, Igor S; Zlobin, Alexander V

2015-01-01T23:59:59.000Z

465

Upgrades of the high resolution imaging x-ray crystal spectrometers on experimental advanced superconducting tokamak  

SciTech Connect

Two imaging x-ray crystal spectrometers, the so-called 'poloidal' and 'tangential' spectrometers, were recently implemented on experimental advanced superconducting tokamak (EAST) to provide spatially and temporally resolved impurity ion temperature (T{sub i}), electron temperature (T{sub e}) and rotation velocity profiles. They are derived from Doppler width of W line for Ti, the intensity ratio of Li-like satellites to W line for Te, and Doppler shift of W line for rotation. Each spectrometer originally consisted of a spherically curved crystal and a two-dimensional multi-wire proportional counter (MWPC) detector. Both spectrometers have now been upgraded. The layout of the tangential spectrometer was modified, since it had to be moved to a different port, and the spectrometer was equipped with two high count rate Pilatus detectors (Model 100 K) to overcome the count rate limitation of the MWPC and to improve its time resolution. The poloidal spectrometer was equipped with two spherically bent crystals to record the spectra of He-like and H-like argon simultaneously and side by side on the original MWPC. These upgrades are described, and new results from the latest EAST experimental campaign are presented.

Lu, B.; Wang, F.; Fu, J.; Li, Y.; Wan, B. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); Shi, Y. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); National Fusion Research Institute, 52 Eoeun-Dong, Yusung-Gu, Daejeon (Korea, Republic of); Bitter, M.; Hill, K. W. [Princeton Plasma Physics Laboratory, MS37-B332, Princeton, New Jersey 08543-0451 (United States); Lee, S. G. [National Fusion Research Institute, 52 Eoeun-Dong, Yusung-Gu, Daejeon (Korea, Republic of)

2012-10-15T23:59:59.000Z

466

First results on disruption mitigation by massive gas injection in Korea Superconducting Tokamak Advanced Research  

SciTech Connect

Massive gas injection (MGI) system was developed on Korea Superconducting Tokamak Advanced Research (KSTAR) in 2011 campaign for disruption studies. The MGI valve has a volume of 80 ml and maximum injection pressure of 50 bar, the diameter of valve orifice to vacuum vessel is 18.4 mm, the distance between MGI valve and plasma edge is {approx}3.4 m. The MGI power supply employs a large capacitor of 1 mF with the maximum voltage of 3 kV, the valve can be opened in less than 0.1 ms, and the amount of MGI can be controlled by the imposed voltage. During KSTAR 2011 campaign, MGI disruptions are carried out by triggering MGI during the flat top of circular and limiter discharges with plasma current 400 kA and magnetic field 2-3.5 T, deuterium injection pressure 39.7 bar, and imposed voltage 1.1-1.4 kV. The results show that MGI could mitigate the heat load and prevent runaway electrons with proper MGI amount, and MGI penetration is deeper under higher amount of MGI or lower magnetic field. However, plasma start-up is difficult after some of D{sub 2} MGI disruptions due to the high deuterium retention and consequently strong outgassing of deuterium in next shot, special effort should be made to get successful plasma start-up after deuterium MGI under the graphite first wall.

Yu Yaowei [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Kim, Young-Ok; Kim, Hak-Kun; Kim, Hong-Tack; Kim, Woong-Chae; Kim, Kwang-Pyo; Son, Soo-Hyun; Bang, Eun-Nam; Hong, Suk-Ho; Yoon, Si-Woo [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Zhuang Huidong [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Chen Zhongyong [Huazhong University of Science and Technology, Wuhan 430074 (China)

2012-12-15T23:59:59.000Z

467

Development of a superconducting connection for niobium cavities  

SciTech Connect

Several, partially successful attempts have been made in the past to develop a superconducting connection between adjacent niobium cavities with the capability to carry up to 30 mT of the magnetic flux. Such a connection would be particularly of great benefit to layouts of long accelerators like ILC because it would shorten the distances between structures and therefore the total length of an accelerator with the associated cost reductions. In addition the superconducting connection would be ideal for a super-structure – two multi-cell cavities connected through a half wavelength long beam pipe providing the coupling. Two welded prototypes of super-structure have been successfully tested with the beam at DESY. The chemical treatment and water rinsing was rather complicated for these prototypes because of the length of the assembly. We have engaged in a program to develop such a connection, initially based on the Nb55Ti material. Several options are pursued such as e.g. a two-cell cavity is being used to explore the reachable magnetic flux for the TESLA like connection with a squeezed niobium gasket between the flanges. Other materials, such as NbZr or NbN are also being considered. In this contribution, we will report about the progress of our investigations.

Peter Kneisel; Gianluigi Ciovati; Jacek Sekutowicz; Waldemar Singer; Xenia Singer; Axel Matheisen

2007-06-22T23:59:59.000Z

468

Development of a superconducting connection for niobium cavities  

SciTech Connect

Several, partially successful attempts have been made in the past to develop a superconducting connection between adjacent niobium cavities with the capability to carry up to 30 mT of the magnetic flux. Such a connection would be particularly of great benefit to layouts of long accelerators like ILC because it would shorten the distances between structures and therefore the total length of an accelerator with the associated cost reductions. In addition the superconducting connection would be ideal for a super-structure – two multi-cell cavities connected through a half wavelength long beam pipe providing the coupling. Two welded prototypes of super-structure have been successfully tested with the beam at DESY. The chemical treatment and water rinsing was rather complicated for these prototypes because of the length of the assembly. We have engaged in a program to develop such a connection, initially based on the Nb55Ti material. Several options are pursued such as e.g. a two-cell cavity is being used to explore the reachable magnetic flux for the TESLA like connection with a squeezed niobium gasket between the flanges. Other materials, such as NbZr or NbN are also being considered. In this contribution, we will report about the progress of our investigations.

Peter Kneisel; Gianluigi Ciovati; Jacek Sekutowicz; Waldemar Singer; Xenia Singer; Axel Matheisen

2007-06-18T23:59:59.000Z

469

ORNL Superconducting Technology Program for Electric Energy Systems  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy's (DOE's) Office of Conservation and Renewable Energy to develop the technology base needed by US industry for commercial development of electric power applications of high-temperature superconductivity. The two major elements of this program are wire development and systems development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from information prepared for the FY 1992 Peer Review of Projects, conducted by DOE's Office of Program Analysis, Office of Energy Research. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer to US industry. Working together, the collaborative teams are making tremendous progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire products.

Hawsey, R.A. (comp.)

1993-02-01T23:59:59.000Z

470

Development of scaling rules for Rutherford type superconducting cables  

SciTech Connect

During the R D phase of the Superconducting Supercollider (SSC) program, LBL was responsible for establishing the parameters for cables used in SSC dipole and quadrupole magnets. In addition, the design and fabrication of a new cable for use in the Low Beta Quadrupoles. As a result of the development work on these and other cables, we have arrived a set of scaling rules which provide guidelines for choosing the parameters for a wide range of superconducting cables. These parameters include strand size, strand number, keystone angle, percent compaction, cable pitch and compacted cable dimensions. In addition, we have defined the tolerance ranges for the key cable manufacturing parameters such as mandrel size and shape, stand tension, and Turkshead temperature control. In this paper, we present the results on cables ranging from 8 strands to 36 strands of 0.65mm wire and from 8 strands to 30 strands of 0.8mm wire. We use these results to demonstrate the application of the scaling rules for Rutherford-type cable.

Royet, J.M.; Scanlan, R.M.

1990-09-01T23:59:59.000Z

471

At the Boundary between Superconducting and Magnetic Oxides  

NLE Websites -- All DOE Office Websites (Extended Search)

At the Boundary between Superconducting and Magnetic Oxides The transistor, which shaped so much of our modern technology and economics, grew out of scientists' desire to gain a greater understanding of the interfaces between different materials. In the same way, today's materials scientists seek to expand our understanding of complex oxides by creating new states at the interface of two materials. Novel growth of complex oxides provides the ability to combine different materials with different and often antagonistic order parameters to create novel, strongly correlated states at the interface. As shown in the article, " Magnetism at the interface between ferromagnetic and superconducting oxides " in the April 2006 issue of Nature Physics, element-resolved x-ray probes and neutrons can be used to construct the first microscopic picture of interactions in a La[subscript 0.7]Ca[subscript 0.3]MnO[subscript 3]/YBa[subscript 2]Cu[subscript 3]O[subscript 7-x] superlattice.

472

Dynamic core length in saturated core fault current limiters  

Science Journals Connector (OSTI)

A saturated core fault current limiter (SCFCL) is a non-linear core-reactor where the core is saturated by an external superconducting DC bias source to achieve a low core permeability at nominal AC currents. Fault current levels in the AC coils de-saturate the core and transform it to a higher permeability state, hence limiting the fault current. In this work we describe the transition between saturated and de-saturated states in three SCFCL configurations. The 'effective core length', Leff, of the SCFCL, defined as the length of the de-saturated AC core limb, is introduced for exploring this transition as a function of the current, I, in the AC coil. Practically, Leff allows one to see the SCFCL as an inductor with a variable core length, allowing calculations of the impedance of the SCFCL over the whole range of operating currents. The Leff(I) curve is further used to calculate the dynamics of the demagnetization factor in a SCFCL. We show that the strong change in the magnetic induction of a SCFCL at high current is the result of both increasing the effective core length and decreasing the demagnetization factor. The method and results presented here serve as an important tool for comparing between various SCFCL concepts not only by comparing their impedance values at the extreme fault and nominal current conditions but also by providing an insight into the full de-saturation process.

Y Nikulshin; Y Wolfus; A Friedman; Y Yeshurun

2013-01-01T23:59:59.000Z

473

Resistive fault current limiter using HTS single-layer coils  

Science Journals Connector (OSTI)

This paper presents the work that is being done as a part of the project to develop a resistive current limiter using HTS Bi-2223/Ag tapes with the same construction scheme previously reported using LTS NbTi/CuNi wire with normal operating current of 170 A in liquid helium bath. The Bi–2223/Ag tape was helically wounded on several cylindrical G-10 tubes forming concentric coils connected in series, parallel or anti-parallel configurations in order to reduce the equivalent inductance of the complete winding. The design targets are the impedance of the electromagnetic system rising to 1.5 ? during a fault occurrence in absence of inductance both in the normal state and in the superconducting state, rated voltage and current of 15 kV and 400 A, respectively, with maximum flux density of 0.1 T. The test results in low voltage (AC/DC) as well as magnetic field measurements at 77 K and 4.2 K are presented and the limiting performance of the system are also discussed.

Carlos A. Baldan; Carlos Y. Shigue; Daltro G. Pinatti; Ernesto Ruppert-Filho; Rafael C. Freitas; Roberto P. Homrich

2004-01-01T23:59:59.000Z

474

High-Tc superconductivity in entirely end-bonded multi-walled carbon nanotubes  

E-Print Network (OSTI)

We report that entirely end-bonded multi-walled carbon nanotubes (MWNTs) can show superconductivity with the transition temperature Tc as high as 12K that is approximately 40-times larger than those reported in ropes of single-walled nanotubes. We find that emergence of this superconductivity is very sensitive to junction structures of Au electrode/MWNTs. This reveals that only MWNTs with optimal numbers of electrically activated shells, which are realized by the end-bonding, can allow the superconductivity due to inter shell effects.

I. Takesue; J. Haruyama; N. Kobayashi; S. Chiashi; S. Maruyama; T. Sugai; H. Shinohara

2005-12-16T23:59:59.000Z

475

Chromomagnetic catalysis of color superconductivity in a (2+1)-dimensional Nambu–Jona-Lasinio model  

Science Journals Connector (OSTI)

We investigate the influence of a constant uniform external chromomagnetic field H on the formation of color superconductivity. The consideration is made in the framework of a (2+1)-dimensional Nambu–Jona-Lasinio model with two different four-fermionic structures responsible for ?q¯q? and diquark ?qq? condensates. In particular, it is shown that there exists a critical value Hc of the external chromomagnetic field such that at H>Hc a nonvanishing diquark condensate is dynamically created (the so-called chromomagnetic catalysis effect of color superconductivity). Moreover, external chromomagnetic fields may in some cases enhance the diquark condensate of color superconductivity.

D. Ebert, K. G. Klimenko, and H. Toki

2001-06-13T23:59:59.000Z

476

Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges  

SciTech Connect

We interpret the experimental observation of a frequency-dependence of superconducting hot electron bolometer (HEB) mixers by taking into account the non-uniform absorption of the terahertz radiation on the superconducting HEB microbridge. The radiation absorption is assumed to be proportional to the local surface resistance of the HEB microbridge, which is computed using the Mattis-Bardeen theory. With this assumption the dc and mixing characteristics of a superconducting niobium-nitride (NbN) HEB device have been modeled at frequencies below and above the equilibrium gap frequency of the NbN film.

Miao, W.; Zhang, W.; Zhong, J. Q.; Shi, S. C., E-mail: scshi@mail.pmo.ac.cn [Purple Mountain Observatory, CAS, 2 West Beijing Road, Nanjing 210008 (China); Delorme, Y.; Lefevre, R.; Feret, A.; Vacelet, T. [Observeratoire de Paris, 61 avenue de l'Observatoire, Paris 75014 (France)

2014-02-03T23:59:59.000Z

477

Transition temperatures and vacancies in superconducting Rb{sub 3}C{sub 60}  

SciTech Connect

We have studied the role of alkali-metal vacancies in the structure and superconductivity in nominal Rb{sub 3}C{sub 60} through preparation of samples with different alkali-metal loadings and annealing temperatures, to search for the possible role of nonstoichiometry in superconductivity. We find sample-to-sample variations of {approx}1 K in the superconducting transition temperature, but this does not correlate with vacancy concentration. We conclude that a model of electronic structure of alkali-metal fullerenes based on proximity to a Mott-Hubbard transition at integer doping is not applicable.

Huq, Ashfia; Stephens, Peter W. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800 (United States)

2005-09-01T23:59:59.000Z

478

Tropical Limit in Statistical Physics  

E-Print Network (OSTI)

Tropical limit for macroscopic systems in equilibrium defined as the formal limit of Boltzmann constant k going to 0 is discussed. It is shown that such tropical limit is well-adapted to analyse properties of systems with highly degenerated energy levels, particularly of frustrated systems like spin ice and spin glasses. Tropical free energy is a piecewise linear function of temperature, tropical entropy is a piecewise constant function and the system has energy for which tropical Gibbs' probability has maximum. Properties of systems in the points of jump of entropy are studied. Systems with finite and infinitely many energy levels and phenomena of limiting temperatures are discussed.

M. Angelelli; B. Konopelchenko

2015-02-04T23:59:59.000Z

479

Linear Collider Final Focus Magnet Construction | Superconducting Magnet  

NLE Websites -- All DOE Office Websites (Extended Search)

Single Strand Superconductor Windings Single Strand Superconductor Windings Initial direct wind quad coils were constructed using 13 mil diameter single strand wire. This wire provides the smallest coil patterns possible, with quad coils wound easily onto .75 inch (19mm) diameter support tubes. The 13mil diameter superconductor gives the smallest coils possible, the penalty being higher inductance and smaller transfer function, but allowing lower operational currents. long model magnet Figure 1 shows the first one foot long model magnet constructed using the 11 axis ultrasonic wiring machine with 13 mil superconducting wire, the same wire previously used for the 472 RHIC Corrector packages. Existing stock materials were used in the construction, and the coil pattern was not optimized for harmonics, but to put as many coil turns onto the tube as

480

Abstract„Production of two types of superconducting  

NLE Websites -- All DOE Office Websites (Extended Search)

68271-AB 68271-AB Abstract submitted to the 17 th International Conf. on Magnet Technology, Geneva, Sept. 24-28, 2001 Test Results for Prototypes of the Twin Aperture Dipoles for the LHC Insertion Region* J. Muratore, M. Anerella, J. Cozzolino, G. Ganetis, A. Ghosh, R. Gupta, M. Harrison, A. Jain, A. Marone, S. Plate, J. Schmalzle, R. Thomas, P. Wanderer, E. Willen and K.C. Wu Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000 Abstract-The Superconducting Magnet Division at Brookhaven National Laboratory (BNL) is building 26 insertion region dipoles of various types for the Large Hadron Collider (LHC) at CERN. These 9.45 m-long, 8 cm aperture magnets use the same coil design as the arc dipoles for the Relativistic Heavy Ion Collider (RHIC) at BNL. The

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


481

Linear Collider Final Focus Magnet Construction | Superconducting Magnet  

NLE Websites -- All DOE Office Websites (Extended Search)

Linear Collider Final Focus Magnet Construction Linear Collider Final Focus Magnet Construction The final focus magnets for the International Linear Collider require very small quadrupoles be placed within the detector background field for both the entrance and exit beams. The use of superconducting magnets for this function provide solutions to several problems confronting the machine designers. One constraint is the operation within the 3 tesla detector field. The direct wind magnets are capable of operation without the use of magnetic materials in their construction, making them ideal for compact focussing solutions within detectors. The second constraint is the small physical size dictated by the crossing angle of the beams and proximity to the IR within the detector solenoid. The Direct Wind design does not require a collar to withstand Lorentz

482

Bio-Med Variable Field MRI Project | Superconducting Magnet Division  

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Bio-Med Variable Field MRI Project Bio-Med Variable Field MRI Project One of the Research and Development projects currently underway is the Bio-Med magnet. Destined for use within the solenoidal field of an MRI, it is designed for use where the subject, in this case a rat, must be tracked in order to obtain an image. Typical MRIs require the subject to remain stationary, and a rat will not normally oblige when it is awake. By moving the composite field (MRI Solenoid plus Bio-Med dipole) to track the rat, it is possible to allow the rat some freedom of motion, while still imaging the brain functions. For the rapid movement typical of a rat, the Bio-Med coil magnet must be capable of very rapid changes in field. Superconducting magnets are typically not designed to allow rapid field variations. To do so typically

483

Cerenkov Radiator Driven by a Superconducting RF Electron Gun  

SciTech Connect

The Naval Postgraduate School (NPS), Niowave, Inc., and Boeing have recently demonstrated operation of the first superconducting RF electron gun based on a quarter wave resonator structure. In preliminary tests, this gun has produced 10 ps long bunches with charge in excess of 78 pC, and with beam energy up to 396 keV. Initial testing occurred at Niowave's Lansing, MI facility, but the gun and diagnostic beam line are planned for installation in California in the near future. The design of the diagnostic beam line is conducive to the addition of a Cerenkov radiator without interfering with other beam line operations. Design and simulations of a Cerenkov radiator, consisting of a dielectric lined waveguide will be presented. The dispersion relation for the structure is determined and the beam interaction is studied using numerical simulations. The characteristics of the microwave radiation produced in both the short and long bunch regimes will be presented.

Poole, B R; Harris, J R

2011-03-07T23:59:59.000Z

484

Cryogen free superconducting splittable quadrupole magnet for linear accelerators  

SciTech Connect

A new superconducting quadrupole magnet for linear accelerators was fabricated at Fermilab. The magnet is designed to work inside a cryomodule in the space between SCRF cavities. SCRF cavities must be installed inside a very clean room adding issues to the magnet design, and fabrication. The designed magnet has a splittable along the vertical plane configuration and could be installed outside of the clean room around the beam pipe previously connected to neighboring cavities. For more convenient assembly and replacement a 'superferric' magnet configuration with four racetrack type coils was chosen. The magnet does not have a helium vessel and is conductively cooled from the cryomodule LHe supply pipe and a helium gas return pipe. The quadrupole generates 36 T integrated magnetic field gradient, has 600 mm effective length, and the peak gradient is 54 T/m. In this paper the quadrupole magnetic, mechanical, and thermal designs are presented, along with the magnet fabrication overview and first test results.

Kashikhin, V.S.; Andreev, N.; Kerby, J.; Orlov, Y.; Solyak, N.; Tartaglia, M.; Velev, G.; /Fermilab

2011-09-01T23:59:59.000Z

485

Cosmological and astrophysical constraints on superconducting cosmic strings  

SciTech Connect

We investigate the cosmological and astrophysical constraints on superconducting cosmic strings (SCSs). SCS loops emit strong bursts of electromagnetic waves, which might affect various cosmological and astrophysical observations. We take into account the effect on the CMB anisotropy, CMB blackbody spectrum, BBN, observational implications on radio wave burst and X-ray or ?-ray events, and stochastic gravitational wave background measured by pulsar timing experiments. We then derive constraints on the parameters of SCS from current observations and estimate prospects for detecting SCS signatures in on-going observations. As a result, we find that these constraints exclude broad parameter regions, and also that on-going radio wave observations can probe large parameter space.

Miyamoto, Koichi [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Nakayama, Kazunori, E-mail: miyamone@icrr.u-tokyo.ac.jp, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp [Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2013-07-01T23:59:59.000Z

486

Superconducting structure with layers of niobium nitride and aluminum nitride  

DOE Patents (OSTI)

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

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

1989-01-01T23:59:59.000Z

487

Superconducting structure with layers of niobium nitride and aluminum nitride  

DOE Patents (OSTI)

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

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

1989-07-04T23:59:59.000Z

488

Nano-superconducting quantum interference devices with suspended junctions  

SciTech Connect

Nano-Superconducting Quantum Interference Devices (nano-SQUIDs) are usually fabricated from a single layer of either Nb or Al. We describe here a simple method for fabricating suspended nano-bridges in Nb/Al thin-film bilayers. We use these suspended bridges, which act as Josephson weak links, to fabricate nano-SQUIDs which show critical current oscillations at temperatures up to 1.5?K and magnetic flux densities up to over 20?mT. These nano-SQUIDs exhibit flux modulation depths intermediate between all-Al and all-Nb devices, with some of the desirable characteristics of both. The suspended geometry is attractive for magnetic single nanoparticle measurements.

Hazra, D.; Hasselbach, K. [Institut Néel, CNRS and Université Joseph Fourier, 25 Avenue des Martyrs, Grenoble (France); Kirtley, J. R. [Center for Probing the Nanoscale, Stanford University, Palo Alto, California 94305-4045 (United States)

2014-04-14T23:59:59.000Z

489

Voltage spike detection in high field superconducting accelerator magnets  

SciTech Connect

A measurement system for the detection of small magnetic flux changes in superconducting magnets, which are due to either mechanical motion of the conductor or flux jump, has been developed at Fermilab. These flux changes are detected as small amplitude, short duration voltage spikes, which are {approx}15mV in magnitude and lasts for {approx}30 {micro}sec. The detection system combines an analog circuit for the signal conditioning of two coil segments and a fast data acquisition system for digitizing the results, performing threshold detection, and storing the resultant data. The design of the spike detection system along with the modeling results and noise analysis will be presented. Data from tests of high field Nb{sub 3}Sn magnets at currents up to {approx}20KA will also be shown.

Orris, D.F.; Carcagno, R.; Feher, S.; Makulski, A.; Pischalnikov, Y.M.; /Fermilab

2004-12-01T23:59:59.000Z

490

Efficient incorporation of silver to improve superconducting fibers  

DOE Patents (OSTI)

An improved method for the efficient incorporation of a metal such as silver in a superconducting material includes blending the metal with a high temperature superconductor or precursor powder and consolidating the same into pellets. The pellets are charged directly into a heating assembly where it is melted and heated sufficiently to a uniform temperature prior to fiberization. Droplets of the melted blend fall through a collar into a nozzle where they are subjected to a high velocity gas to break the melted material into ligaments which solidify into improved flexible fibers having the metal homogeneously dis This invention was made with Government support under a contract with the Department of Energy (DOE) and Ames Laboratory, Contract No. SC-91-225, our reference No. CRD-1272. The Government has certain rights in this invention.

Gleixner, Richard A. (North Canton, OH); LaCount, Dale F. (Alliance, OH); Finnemore, Douglas K. (Ames, IA)

1994-04-26T23:59:59.000Z

491

Shock-induced synthesis of high temperature superconducting materials  

DOE Patents (OSTI)

It has now been determined that the unique features of the high press