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Note: This page contains sample records for the topic "temperature superconducting magnetic" 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.


1

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

E-Print Network [OSTI]

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

Weston, Ken

2

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

3

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

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

Hassenzahl, W.

2011-01-01T23:59:59.000Z

4

High-field magnets using high-critical-temperature superconducting thin films  

DOE Patents [OSTI]

High-field magnets fabricated from high-critical-temperature superconducting ceramic (HTSC) thin films which can generate fields greater than 4 Tesla are disclosed. The high-field magnets are made of stackable disk-shaped substrates coated with HTSC thin films, and involves maximizing the critical current density, superconducting film thickness, number of superconducting layers per substrate, substrate diameter, and number of substrates while minimizing substrate thickness. The HTSC thin films are deposited on one or both sides of the substrates in a spiral configuration with variable line widths to increase the field. 4 figures.

Mitlitsky, F.; Hoard, R.W.

1994-05-10T23:59:59.000Z

5

High-field magnets using high-critical-temperature superconducting thin films  

DOE Patents [OSTI]

High-field magnets fabricated from high-critical-temperature superconducting ceramic (HTSC) thin films which can generate fields greater than 4 Tesla. The high-field magnets are made of stackable disk-shaped substrates coated with HTSC thin films, and involves maximizing the critical current density, superconducting film thickness, number of superconducting layers per substrate, substrate diameter, and number of substrates while minimizing substrate thickness. The HTSC thin films are deposited on one or both sides of the substrates in a spiral configuration with variable line widths to increase the field.

Mitlitsky, Fred (Livermore, CA); Hoard, Ronald W. (Livermore, CA)

1994-01-01T23:59:59.000Z

6

Superconducting Magnet Division  

E-Print Network [OSTI]

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

7

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

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

Hassenzahl, W.

2011-01-01T23:59:59.000Z

8

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

9

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

10

Superconducting Magnet Division  

E-Print Network [OSTI]

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

McDonald, Kirk

11

Superconducting Magnet Division  

E-Print Network [OSTI]

Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R Slotted Dipole Corrector Design · Slots are machined in an Al tube where superconducting wires are placed between superconducting and copper solenoid with superconducting solenoid at 6T · The desired field (>0

Ohta, Shigemi

12

QUENCHES IN LARGE SUPERCONDUCTING MAGNETS  

E-Print Network [OSTI]

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

Eberhard, P.H.

2010-01-01T23:59:59.000Z

13

Fast superconducting magnetic field switch  

DOE Patents [OSTI]

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

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

1996-01-01T23:59:59.000Z

14

Superconducting magnetic coil  

DOE Patents [OSTI]

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

Aized, D.; Schwall, R.E.

1999-06-22T23:59:59.000Z

15

Superconducting magnetic coil  

DOE Patents [OSTI]

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

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

1999-06-22T23:59:59.000Z

16

High temperature superconductor micro-superconducting-quantum-interference-device magnetometer for magnetization measurement of a microscale magnet  

SciTech Connect (OSTI)

We have developed a high temperature superconductor (HTS) micrometer-sized dc superconducting quantum interference device (SQUID) magnetometer for high field and high temperature operation. It was fabricated from YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} of 92 nm in thickness with photolithography techniques to have a hole of 4x9 {mu}m{sup 2} and 2 {mu}m wide grain boundary Josephson junctions. Combined with a three dimensional magnetic field coil system, the modulation patterns of critical current I{sub c} were observed for three different field directions. They were successfully used to measure the magnetic properties of a molecular ferrimagnetic microcrystal (23x17x13 {mu}m{sup 3}), [Mn{sub 2}(H{sub 2}O){sub 2}(CH{sub 3}COO)][W(CN){sub 8}]{center_dot}2H{sub 2}O. The magnetization curve was obtained in magnetic field up to 0.12 T between 30 and 70 K. This is the first to measure the anisotropy of hysteresis curve in the field above 0.1 T with an accuracy of 10{sup -12} J T{sup -1} (10{sup -9} emu) with a HTS micro-SQUID magnetometer.

Takeda, Keiji [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); Department of Chemistry, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Mori, Hatsumi [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Yamaguchi, Akira; Ishimoto, Hidehiko [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); Nakamura, Takayoshi [CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Research Institute for Electronic Science, Hokkaido University, Kita 12 Nishi 6, Sapporo-shi, Hokkaido 060-0812 (Japan); Kuriki, Shinya [Research Institute for Electronic Science, Hokkaido University, Kita 12 Nishi 6, Sapporo-shi, Hokkaido 060-0812 (Japan); Hozumi, Toshiya; Ohkoshi, Shin-ichi [Department of Chemistry, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan)

2008-03-15T23:59:59.000Z

17

Philosophy 26 High Temperature Superconductivity  

E-Print Network [OSTI]

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

Callender, Craig

18

Superconducting Magnet Technology for Future Hadron Colliders  

E-Print Network [OSTI]

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

Scanlan, R.M.

2011-01-01T23:59:59.000Z

19

High temperature interfacial superconductivity  

DOE Patents [OSTI]

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

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

2012-06-19T23:59:59.000Z

20

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

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Superconductivity and Magnetism: Materials Properties  

E-Print Network [OSTI]

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

22

Superconducting Magnet Division Mike Harrison  

E-Print Network [OSTI]

Superconducting Magnet Division Mike Harrison The LARP Dipole R&D Program - D1 only Design (high beta lattice location) · Beam heating (first active element from the IP) #12;Superconducting aperture Field quality Issues not (well ?) understood #12;Superconducting Magnet Division Mike Harrison

Large Hadron Collider Program

23

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

24

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

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

Hassenzahl, W.

2011-01-01T23:59:59.000Z

25

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

26

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. 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.

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

1996-01-01T23:59:59.000Z

27

Superconducting Magnets for Particle Accelerators  

E-Print Network [OSTI]

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

Rossi, L

2012-01-01T23:59:59.000Z

28

Characterization of a high-temperature superconducting conductor on round core cables in magnetic fields up to 20 T  

SciTech Connect (OSTI)

The next generation of high-field magnets that will operate at magnetic fields substantially above 20 T, or at temperatures substantially above 4.2 K, requires high-temperature superconductors (HTS). Conductor on round core (CORC) cables, in which RE-Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} (RE = rare earth) (REBCO) coated conductors are wound in a helical fashion on a fl?exible core, are a practical and versatile HTS cable option for low-inductance, high-field magnets. We performed the first tests of CORC magnet cables in liquid helium in magnetic fields of up to 20 T. A record critical current I{sub c} of 5021 A was measured at 4.2 K and 19 T. In a cable with an outer diameter of 7.5 mm, this value corresponds to an engineering current density J{sub e} of 114 A mm{sup -2} , the highest J{sub e} ever reported for a superconducting cable at such high magnetic fields. Additionally, the first magnet wound from an HTS cable was constructed from a 6 m-long CORC cable. The 12-turn, double-layer magnet had an inner diameter of 9 cm and was tested in a magnetic field of 20 T, at which it had an I{sub c} of 1966 A. The cables were quenched repetitively without degradation during the measurements, demonstrating the feasibility of HTS CORC cables for use in high-field magnet applications.

van der Laan, Danko [Advanced Conductor Technologies; Noyes, Patrick [National High Magnetic Field Laboratory; Miller, George [National High Magnetic Field Laboratory; Weijers, Hubertus [National High Magnetic Field Laboratory; Willering, Gerard [CERN

2013-02-13T23:59:59.000Z

29

atlas superconducting magnet: Topics by E-print Network  

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

30

Superconducting pipes and levitating magnets  

E-Print Network [OSTI]

Motivated by a beautiful demonstration of the Faraday's and Lenz's law in which a small neodymium magnet falls slowly through a conducting non-ferromagnetic tube, we consider the dynamics of a magnet falling through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be suspended over the front edge. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius $a$ and length $L \\approx a$ decays, in the axial direction, with a characteristic length $\\xi \\approx 0.26 a$. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices, SQUIDs. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.

Yan Levin; Felipe B. Rizzato

2006-09-15T23:59:59.000Z

31

Freely oriented portable superconducting magnet  

DOE Patents [OSTI]

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

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

2010-01-12T23:59:59.000Z

32

HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network [OSTI]

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

Taylor, C.

2011-01-01T23:59:59.000Z

33

An investigation into high temperature superconducting flux pump technology with the circular type magnetic flux pump devices and YBaCuO films  

E-Print Network [OSTI]

The rapid development of second generation (2G) high temperature superconducting (HTS) wires in the last decade has made it possible to wind high quality 2G HTS coils. These 2G HTS coils show promise for future applications such as magnetic...

Wang, Wei

2014-06-10T23:59:59.000Z

34

Superconducting magnetic energy storage  

SciTech Connect (OSTI)

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

35

Spontaneous brillouin scattering quench diagnostics for large superconducting magnets  

E-Print Network [OSTI]

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

Mahar, Scott B

2008-01-01T23:59:59.000Z

36

Recent Developments in High Temperature Superconductivity  

E-Print Network [OSTI]

three-dimensional superconductor which can be teclmologically important if its superconducting transition Tc can be enhanced to be above the temperature liquid nitrogen. Possible superconductivity above room temperature has been reported in a... mixture of CuBr and CuBr2 system [8]. A mid-point resistive transition of 346K (73C) is observed but it is not confirmed by magnetic measurements. BCSCO and TCBCO The new series of high Tc superconductors is characterized by the chemical formula A2B2...

Hor, P. H.

37

Coexisting Superconductivity and Magnetism in UCoGe Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network [OSTI]

Coexisting Superconductivity and Magnetism in UCoGe Gregory S. Boebinger, National High Magnetic focused on the coexistence of superconductivity and ferromagnetism, including UGe2, URhGe, and UCoGe. In these materials, superconductivity develops below the ferromagnetic Curie temperature TC without destroying

Weston, Ken

38

DESIGN REQUIREMENTS AND OPTIONS FOR FINAL FOCUSING SUPERCONDUCTING MAGNETS  

E-Print Network [OSTI]

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

California at San Diego, University of

39

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

40

Damping in high-temperature superconducting levitation systems  

DOE Patents [OSTI]

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

Hull, John R. (Sammamish, WA)

2009-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

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

42

High Temperature Superconductivity in Cuprates: a model  

E-Print Network [OSTI]

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

P. R. Silva

2010-07-16T23:59:59.000Z

43

HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network [OSTI]

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

Taylor, C.

2011-01-01T23:59:59.000Z

44

High-Temperature Superconductivity  

ScienceCinema (OSTI)

Like astronomers tweaking images to gain a more detailed glimpse of distant stars, physicists at Brookhaven National Laboratory have found ways to sharpen images of the energy spectra in high-temperature superconductors ? materials that carry electrical c

Peter Johnson

2010-01-08T23:59:59.000Z

45

FORCED TWO PHASE HELIUM COOLING OF LARGE SUPERCONDUCTING MAGNETS  

E-Print Network [OSTI]

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

Green, M.A.

2010-01-01T23:59:59.000Z

46

Progress on Superconducting Magnets for the MICE Cooling Channel  

E-Print Network [OSTI]

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

Green, Michael A

2010-01-01T23:59:59.000Z

47

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

E-Print Network [OSTI]

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

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

48

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

E-Print Network [OSTI]

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

49

Magnetism and superconductivity observed to exist in harmony  

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

50

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

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

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

51

Static forces in a superconducting magnet bearing  

SciTech Connect (OSTI)

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

52

Superconducting magnets for muon capture and phase rotation  

E-Print Network [OSTI]

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

Green, M.A.

2011-01-01T23:59:59.000Z

53

High Temperature Superconducting Underground Cable  

SciTech Connect (OSTI)

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

54

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

E-Print Network [OSTI]

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

Green, M.A.

2008-01-01T23:59:59.000Z

55

Convective heat transfer model for determining quench recovery of high temperature superconducting YBCO in liquid nitrogen  

E-Print Network [OSTI]

Stability of a superconducting magnet is critical for reliable operation of a device in which the magnet plays a role. With the advent of high temperature superconductors (HTS), liquid nitrogen may be used to cool HTS ...

Jankowski, Joseph Edward, 1980-

2004-01-01T23:59:59.000Z

56

Progress on Superconducting Magnets for the MICE Cooling Channel  

E-Print Network [OSTI]

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

Green, Michael A

2010-01-01T23:59:59.000Z

57

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

58

A superconducting dipole magnet for laser spectroscopy  

E-Print Network [OSTI]

A SUPERCONDUCTING DIPOLE MAGNET FOR LASER SPECTROSCOPY A Thesis by KENNETH EDWARD WAGENHAUSER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requhements for the degree of MASTER OF SCIENCE... May 1990 Major subject: Physics A SUPERCONDUCTING DIPOLE MAGNET FOR LASER SPECTROSCOPY A thesis by KENNETH EDWARD WAGENHAUSER Approved to as to style and content by: Hans A. Schuessler (Chair of Committee) David H. Russell (Member) Glenn A...

Wagenhauser, Kenneth Edward

1990-01-01T23:59:59.000Z

59

Probes for investigating the effect of magnetic field, field orientation, temperature and strain on the critical current density of anisotropic high-temperature superconducting tapes in a split-pair 15 T horizontal magnet  

SciTech Connect (OSTI)

We present the designs of probes for making critical current density (J{sub c}) measurements on anisotropic high-temperature superconducting tapes as a function of field, field orientation, temperature and strain in our 40 mm bore, split-pair 15 T horizontal magnet. Emphasis is placed on the design of three components: the vapour-cooled current leads, the variable temperature enclosure, and the springboard-shaped bending beam sample holder. The vapour-cooled brass critical-current leads used superconducting tapes and in operation ran hot with a duty cycle (D) of ?0.2. This work provides formulae for optimising cryogenic consumption and calculating cryogenic boil-off, associated with current leads used to make J{sub c} measurements, made by uniformly ramping the current up to a maximum current (I{sub max}) and then reducing the current very quickly to zero. They include consideration of the effects of duty cycle, static helium boil-off from the magnet and Dewar (b{sup ?}), and the maximum safe temperature for the critical-current leads (T{sub max}). Our optimized critical-current leads have a boil-off that is about 30% less than leads optimized for magnet operation at the same maximum current. Numerical calculations show that the optimum cross-sectional area (A) for each current lead can be parameterized by LI{sub max}/A=[1.46D{sup ?0.18}L{sup 0.4}(T{sub max}?300){sup 0.25D{sup ?{sup 0{sup .{sup 0{sup 9}}}}}}+750(b{sup ?}/I{sub max})D{sup 10{sup ?{sup 3I{sub m}{sub a}{sub x}?2.87b{sup ?}}}}]× 10{sup 6}A m{sup ?1} where L is the current lead's length and the current lead is operated in liquid helium. An optimum A of 132 mm{sup 2} is obtained when I{sub max} = 1000 A, T{sub max} = 400 K, D = 0.2, b{sup ?} = 0.3 l?h{sup ?1} and L = 1.0 m. The optimized helium consumption was found to be 0.7 l?h{sup ?1}. When the static boil-off is small, optimized leads have a boil-off that can be roughly parameterized by: b/I{sub max?} ? (1.35 × 10{sup ?3})D{sup 0.41} l?h{sup ?1}?A{sup ?1}. A split-current-lead design is employed to minimize the rotation of the probes during the high current measurements in our high-field horizontal magnet. The variable-temperature system is based on the use of an inverted insulating cup that operates above 4.2 K in liquid helium and above 77.4 K in liquid nitrogen, with a stability of ±80 mK to ±150 mK. Uniaxial strains of ?1.4% to 1.0% can be applied to the sample, with a total uncertainty of better than ±0.02%, using a modified bending beam apparatus which includes a copper beryllium springboard-shaped sample holder.

Sunwong, P.; Higgins, J. S.; Hampshire, D. P. [Superconductivity Group, Centre for Materials Physics, Department of Physics, University of Durham, Durham DH1 3LE (United Kingdom)

2014-06-15T23:59:59.000Z

60

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

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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.


61

Induced Magnetism in Color-Superconducting Media  

E-Print Network [OSTI]

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

Efrain J. Ferrer

2010-01-22T23:59:59.000Z

62

High temperature superconducting fault current limiter  

DOE Patents [OSTI]

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

Hull, J.R.

1997-02-04T23:59:59.000Z

63

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

DOE Patents [OSTI]

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

Tekletsadik, Kasegn D. (Rexford, NY)

2007-10-16T23:59:59.000Z

64

Superconducting magnets for muon capture and phase rotation  

E-Print Network [OSTI]

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

Green, M.A.

2011-01-01T23:59:59.000Z

65

A Superconducting Bending Magnet System for a Compact Synchrotron Light Source  

E-Print Network [OSTI]

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

Green, M.A.

2011-01-01T23:59:59.000Z

66

A SUPERCONDUCTING MAGNET SYSTEM FOR THE SPIRIT COSMIC RAY SPACE TELESCOPE  

E-Print Network [OSTI]

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

Green, M.A.

2010-01-01T23:59:59.000Z

67

A probe for investigating the effects of temperature, strain, and magnetic field on transport critical currents in superconducting  

E-Print Network [OSTI]

magnetic fields. The strain is applied to the wire by soldering it to a thick coiled spring and twisting one end of the spring with respect to the other. Strain can be applied reversibly from 0.7% to 0 to test long straight samples can be constructed for use in split-coil magnets, but the maximum field

Hampshire, Damian

68

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

69

Towards Computing Ratcheting and Training in Superconducting Magnets  

E-Print Network [OSTI]

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

Ferracin, Paolo

2009-01-01T23:59:59.000Z

70

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

E-Print Network [OSTI]

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

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

2014-12-12T23:59:59.000Z

71

Critical temperatures of superconducting solders  

E-Print Network [OSTI]

Different magnetic strengths in MRIs produce different reactions and provide more insight into what being imaged. Being able to more quickly switch between two or more different magnet strengths would allow scientists in ...

Pavão, Erica Medeiros

2007-01-01T23:59:59.000Z

72

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

73

Superconducting Magnets Research for a Viable US Fusion Program  

E-Print Network [OSTI]

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini, Leslie Superconductivity Center, Florida State University 2014 FESAC Strategic Planning (SP) Panel June 5, 2014 program now has the opportunity to take a world- leading role in making high field superconducting magnets

74

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini1  

E-Print Network [OSTI]

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini1 , Leslie fusion reactors rely on superconducting magnets for efficient and reliable production of these magnetic fields. Future superconducting magnets for fusion

75

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

E-Print Network [OSTI]

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

76

Journal of Superconductivity, Vol. 5, No. 4, 1992 Magnetic Penetration Depth Measurements in  

E-Print Network [OSTI]

of superconductivity is the diamagnetic response of a superconductor below its transition temperature To. The abilityJournal of Superconductivity, Vol. 5, No. 4, 1992 Magnetic Penetration Depth Measurements in Cuprate Superconductors Steven M. AnlageI and Dong-Ho Wut Received 16 April 1992 We examine recent results

Anlage, Steven

77

Superconducting magnet for nuclei orientation  

E-Print Network [OSTI]

SUPERCOMDUCTING MAGNET FOR NUCLEI ORIENTATION A . Thesis Pa-Chung Wang Submitted. to the Graduate Co11ege of the Texas AEON University in partial fulfillment of the requirements for the degree of NASTEB OP SCIENCE Nay 1968 Nagor Sub...)cot: Physlos SUPEECOKDUCTING MAGNET FOE NUCLEI OBIENTATION A Thesis by Fa-Chung Wang Approved as to style and content byi (Chairman of Committee) Head of Department) Berber i ~ . /' (joe-ber) / f ~;: ( Niay 1968 + & 0 & z c. i ACKNOWLEDGENENTS...

Wang, Fa-Chung

1968-01-01T23:59:59.000Z

78

Superconducting Magnet Safety Nuclear Magnetic Resonance (NMR) facilities present unique hazards not found in most  

E-Print Network [OSTI]

Superconducting Magnet Safety Nuclear Magnetic Resonance (NMR) facilities present unique hazards not found in most laboratory environments. The NMR facilities maintain superconducting magnets which have for asphyxiation. Once energized the field of the superconducting magnet of the spectrometer is always present

Maroncelli, Mark

79

Two phase cooling for superconducting magnets  

SciTech Connect (OSTI)

A closed circuit tubular cooling system for superconducting magnets offers advantages of limiting boiloff and containing high pressures during quenches. Proper location of automatic valves to lower pressures and protect the refrigerator in the event of quenches is described. Theoretical arguments and exprimental evidence are given against a previously suggested method to determine He two phase flow regimes. If loss of flow occurs due to some types of refrigeration failure and transfer lines have enough heat leak to warm up, quenches are induced when the flow is restored. Examples are taken from experience with the TPC magnet.

Eberhard, P.H.; Gibson, G.A.; Green, M.A.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Watt, R.D.

1985-08-01T23:59:59.000Z

80

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

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Nb3Sn superconducting magnets for electron cyclotron resonance ion sources  

E-Print Network [OSTI]

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

Ferracin, P.

2011-01-01T23:59:59.000Z

82

Novel Approach to Linear Accelerator Superconducting Magnet System  

SciTech Connect (OSTI)

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

83

High-Temperature Superconducting Composite Conductors  

DOE Patents [OSTI]

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

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

2005-01-18T23:59:59.000Z

84

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

85

Cooling system for superconducting magnet  

DOE Patents [OSTI]

A cooling system is configured to control the flow of a refrigerant by controlling the rate at which the refrigerant is heated, thereby providing an efficient and reliable approach to cooling a load (e.g., magnets, rotors). The cooling system includes a conduit circuit connected to the load and within which a refrigerant circulates; a heat exchanger, connected within the conduit circuit and disposed remotely from the load; a first and a second reservoir, each connected within the conduit, each holding at least a portion of the refrigerant; a heater configured to independently heat the first and second reservoirs. In a first mode, the heater heats the first reservoir, thereby causing the refrigerant to flow from the first reservoir through the load and heat exchanger, via the conduit circuit and into the second reservoir. In a second mode, the heater heats the second reservoir to cause the refrigerant to flow from the second reservoir through the load and heat exchanger via the conduit circuit and into the first reservoir. 3 figs.

Gamble, B.B.; Sidi-Yekhlef, A.

1998-12-15T23:59:59.000Z

86

Superconducting magnetic energy storage for asynchronous electrical systems  

DOE Patents [OSTI]

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

Boenig, H.J.

1984-05-16T23:59:59.000Z

87

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

88

Toroidal constant-tension superconducting magnetic energy storage units  

DOE Patents [OSTI]

A superconducting magnetic energy storage unit is provided in which the magnet is wound in a toroidal fashion such that the magnetic field produced is contained only within the bore of the magnet, and thus producing a very low external field. The superconducting magnet includes a coolant channel disposed through the wire. The bore of the magnet comprises a storage volume in which cryogenic coolant is stored, and this volume supplies the coolant to be delivered to the coolant channel in the magnet. 6 figs.

Herring, J.S.

1992-11-03T23:59:59.000Z

89

Superconducting transition temperature in heterogeneous ferromagnet-superconductor systems  

E-Print Network [OSTI]

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

Pokrovsky, Valery L.; Wei, HD.

2004-01-01T23:59:59.000Z

90

High temperature superconductivity in metallic region near Mott transition  

E-Print Network [OSTI]

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

Tian De Cao

2009-09-11T23:59:59.000Z

91

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

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

92

astromag superconducting magnet: Topics by E-print Network  

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

M N; Verschelde, Henri 2012-01-01 122 Superconducting Magnet for Non-Neutral Plasma Research Alexei V. Dudarev, Victor E. Keilin, Nicolai Ph. Kopeikin, Igor O. Shugaev,...

93

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

94

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

E-Print Network [OSTI]

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

Sayles, Todd Allen

2008-01-01T23:59:59.000Z

95

Support system design for a superconducting MRI magnet  

E-Print Network [OSTI]

Cylindrical cold mass surrounded by an aluminum radiation shield and suspended by two stainless steel rods 2. 2 Ratio of dynamic displacement to static displacement vs. ratio of shock duration to natural period 2. 3 Ratio of dynamic displacement to static... Windmgs Axial Figure 2. 1 Cylindrical cold mass surrounded by an aluminum radiation shield and suspended by two stainless steel rods In a superconducting magnet the magnetic field is dependent on the current in the superconducting wires, the position...

Watts, Louis Chad

1993-01-01T23:59:59.000Z

96

Critical magnetic field of surface superconductivity in lead  

SciTech Connect (OSTI)

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

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

2011-12-15T23:59:59.000Z

97

High performance magnetic bearing systems using high temperature superconductors  

DOE Patents [OSTI]

A magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly.

Abboud, Robert G. (Barrington Hills, IL)

1998-01-01T23:59:59.000Z

98

High performance magnetic bearing systems using high temperature superconductors  

DOE Patents [OSTI]

Disclosed are a magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly. 7 figs.

Abboud, R.G.

1998-05-05T23:59:59.000Z

99

Journal of Superconductivity: Incorporating Novel Magnetism ( C 2005) DOI: 10.1007/s10948-005-0005-2  

E-Print Network [OSTI]

Journal of Superconductivity: Incorporating Novel Magnetism ( C 2005) DOI: 10.1007/s10948) and a 10 °A thick Ge spacer layer. From temperature- dependent magnetization and hysteresis loop; ferromagnetism; MBE. Recently, magnetic semiconductors have at- tracted great attention due to the potential

Medvedeva, Julia E.

100

Superconducting Magnet Technology for Future Hadron Colliders  

E-Print Network [OSTI]

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

Scanlan, R.M.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Using fiberglass volumes for VPI of superconductive magnetic systems’ insulation  

SciTech Connect (OSTI)

The paper describes the method of manufacturing fiberglass molds for vacuum pressure impregnation (VPI) of high-voltage insulation of superconductive magnetic systems (SMS) with epoxidian hot-setting compounds. The basic advantages of using such vacuum volumes are improved quality of insulation impregnation in complex-shaped areas, and considerable cost-saving of preparing VPI of large-sized components due to dispensing with the stage of fabricating a metal impregnating volume. Such fiberglass vacuum molds were used for VPI of high-voltage insulation samples of an ITER reactor’s PF1 poloidal coil. Electric insulation of these samples has successfully undergone a wide range of high-voltage and mechanical tests at room and cryogenic temperatures. Some results of the tests are also given in this paper.

Andreev, I. S.; Bezrukov, A. A.; Pischugin, A. B. [Sredne-Nevskiy Shipyard (SNSZ), 10 Zavodskaya str., c. Pontonniy, Saint-Petersburg (Russian Federation); Bursikov, A. S.; Klimchenko, Y. A.; Marushin, E. L.; Mednikov, A. A.; Rodin, I. Y.; Stepanov, D. B. [The D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), 3 Doroga na Metallostroy, Metallostroy, Saint-Petersburg (Russian Federation)

2014-01-29T23:59:59.000Z

102

Manipulating the magnetic state of a carbon nanotube Josephson junction using the superconducting phase  

E-Print Network [OSTI]

We study the supercurrent of a carbon nanotube quantum dot Josephson junction in a parameter regime in which the Kondo energy and the superconducting gap are of comparable size. For gate voltages in the vicinity of a Kondo ridge the superconducting phase difference can then be used to tune the magnetic state from a singlet to a doublet. Accordingly our measured current phase relation crosses over from 0 to $\\pi$-junction behavior, exhibiting strong anharmonicities. The experimental results are in excellent agreement with our numerically exact finite temperature quantum Monte Carlo simulations and provide insights on the phase-controlled level-crossing transition at zero temperature.

R. Delagrange; D. J. Luitz; R. Weil; A. Kasumov; V. Meden; H. Bouchiat; R. Deblock

2015-01-14T23:59:59.000Z

103

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

E-Print Network [OSTI]

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

Green, M.A.

2010-01-01T23:59:59.000Z

104

Superconducting Magnet for Non-Neutral Plasma Research  

E-Print Network [OSTI]

A superconducting magnet intended for nonneutral electron plasma research has been developed and manufactured. The 260 mm room-temperature horizontal bore magnet consists of a main 3 T coil and of two orthogonal pairs of saddle-shaped steering coils, each capable of producing transverse fields of up to 0.03 T. The axial field is homogeneous in a 100 mm diameter and 600 mm long cylindrical volume within 0.25%, the azimuthal inhomogeneity within the same volume is less than 0.01%. All windings operate in a persistent current mode. The liquid helium evaporation rate is less than 6 l/day. The magnet has operated successfully at the University of California, Berkeley, since the first half of 1995. I. INTRODUCTION Over the last decade, non-neutral plasma studies have proven to be one of the most fruitful areas of research in basic plasma physics [1],[2]. Pure electron, ion, positron, and anti-proton plasmas have been created. Non-neutral plasma research is applicable to several other physi...

Alexei Dudarev Victor; Victor E. Keilin; Nicolai Ph. Kopeikin; Igor O. Shugaev; Er V. Stepanenko; Vadim V. Stepanov

105

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

E-Print Network [OSTI]

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

Metlushko, Vitali

106

Operational experience with superconducting synchrotron magnets  

SciTech Connect (OSTI)

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

Martin, P.S.

1987-03-01T23:59:59.000Z

107

Structural performance of the first SSC (Superconducting Super Collider) Design B dipole magnet  

SciTech Connect (OSTI)

The first Design B Superconducting Super Collider (SSC) dipole magnet has been successfully tested. This magnet was heavily instrumented with temperature and strain gage sensors in order to evaluate its adherence to design constraints and design calculations. The instrumentation and associated data acquisition system allowed monitoring of the magnet during cooldown, warmup, and quench testing. This paper will focus on the results obtained from structural measurements on the suspension system during normal and rapid cooldowns and during quench studies at full magnet current. 4 refs., 9 figs.

Nicol, T.H.

1989-09-01T23:59:59.000Z

108

Superconducting magnetic Wollaston prism for neutron spin encoding  

SciTech Connect (OSTI)

A magnetic Wollaston prism can spatially split a polarized neutron beam into two beams with different neutron spin states, in a manner analogous to an optical Wollaston prism. Such a Wollaston prism can be used to encode the trajectory of neutrons into the Larmor phase associated with their spin degree of freedom. This encoding can be used for neutron phase-contrast radiography and in spin echo scattering angle measurement (SESAME). In this paper, we show that magnetic Wollaston prisms with highly uniform magnetic fields and low Larmor phase aberration can be constructed to preserve neutron polarization using high temperature superconducting (HTS) materials. The Meissner effect of HTS films is used to confine magnetic fields produced electromagnetically by current-carrying HTS tape wound on suitably shaped soft iron pole pieces. The device is cooled to ?30 K by a closed cycle refrigerator, eliminating the need to replenish liquid cryogens and greatly simplifying operation and maintenance. A HTS film ensures that the magnetic field transition within the prism is sharp, well-defined, and planar due to the Meissner effect. The spin transport efficiency across the device was measured to be ?98.5% independent of neutron wavelength and energizing current. The position-dependent Larmor phase of neutron spins was measured at the NIST Center for Neutron Research facility and found to agree well with detailed simulations. The phase varies linearly with horizontal position, as required, and the neutron beam shows little depolarization. Consequently, the device has advantages over existing devices with similar functionality and provides the capability for a large neutron beam (20 mm × 30 mm) and an increase in length scales accessible to SESAME to beyond 10 ?m. With further improvements of the external coupling guide field in the prototype device, a larger neutron beam could be employed.

Li, F., E-mail: fankli@indiana.edu; Parnell, S. R.; Wang, T.; Baxter, D. V. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States)] [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Hamilton, W. A. [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)] [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States); Maranville, B. B. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)] [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Semerad, R. [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany)] [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany); Cremer, J. T. [Adelphi Technology Inc., Redwood City, California 94063 (United States)] [Adelphi Technology Inc., Redwood City, California 94063 (United States); Pynn, R. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States) [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)

2014-05-15T23:59:59.000Z

109

Superconducting coherence length and magnetic penetration depth of a p-wave holographic superconductor  

SciTech Connect (OSTI)

A classical SU(2) Einstein-Yang-Mills theory in (3+1)-dimensional anti-de Sitter spacetime is believed to be dual to a p-wave superconductor in (2+1)-dimensional flat spacetime. In order to calculate the superconducting coherence length {xi} of the holographic superconductor near the superconducting phase transition point, we make a perturbative study of the gravity theory analytically. The superconducting coherence length {xi} is found to be proportional to (1-T/T{sub c}){sup -1/2} near the critical temperature T{sub c}. We also obtain the magnetic penetration depth {lambda}{proportional_to}(T{sub c}-T){sup 1/2} by adding a small external homogeneous magnetic field. The results agree with the Ginzburg-Landau theory.

Zeng Huabi; Fan Zheyong [Department of Physics, Nanjing University, Nanjing 210093 (China); Zong Hongshi [Department of Physics, Nanjing University, Nanjing 210093 (China); Joint Center for Particle, Nuclear Physics and Cosmology, Nanjing 210093 (China)

2010-05-15T23:59:59.000Z

110

Cryogen free superconducting splittable quadrupole magnet for linear accelerators  

SciTech Connect (OSTI)

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

111

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

112

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

113

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

114

Low-temperature magnetic refrigerator  

DOE Patents [OSTI]

The invention relates to magnetic refrigeration and more particularly to low temperature refrigeration between about 4 and about 20 K, with an apparatus and method utilizing a belt of magnetic material passed in and out of a magnetic field with heat exchangers within and outside the field operably disposed to accomplish refrigeration.

Barclay, J.A.

1983-05-26T23:59:59.000Z

115

Rotor assembly including superconducting magnetic coil  

DOE Patents [OSTI]

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

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

2003-01-01T23:59:59.000Z

116

Magnetar superconductivity versus magnetism: neutrino cooling processes  

E-Print Network [OSTI]

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

Sinha, Monika

2015-01-01T23:59:59.000Z

117

Magnetic Flux Dynamics in Horizontally Cooled Superconducting Cavities  

E-Print Network [OSTI]

Previous studies on magnetic flux expulsion as a function of cooling details have been performed for superconducting niobium cavities with the cavity beam axis placed parallel respect to the helium cooling flow, and findings showed that for sufficient cooling thermogradients all magnetic flux could be expelled and very low residual resistance could be achieved. In this paper we investigate the flux trapping and its impact on radio frequency surface resistance when the resonators are positioned perpendicularly to the helium cooling flow, which is representative of how superconducting radio-frequency (SRF) cavities are cooled in an accelerator. We also extend the studies to different directions of applied magnetic field surrounding the resonator. Results show that in the cavity horizontal configuration there is a different impact of the various field components on the final surface resistance, and that several parameters have to be considered to understand flux dynamics. A newly discovered phenomenon of concent...

Martinello, M; Grassellino, A; Crawford, A C; Melnychuk, O; Romanenko, A; Sergatkov, D A

2015-01-01T23:59:59.000Z

118

Magnetic Phases in Three-Flavor Color Superconductivity  

E-Print Network [OSTI]

The best natural candidates for the realization of color superconductivity are quark stars -not yet confirmed by observation- and the extremely dense cores of compact stars, many of which have very large magnetic fields. To reliably predict astrophysical signatures of color superconductivity, a better understanding of the role of the star's magnetic field in the color superconducting phase that realizes in the core is required. This paper is an initial step in that direction. The field scales at which the different magnetic phases of a color superconductor with three quark flavors can be realized are investigated. Coming from weak to strong fields, the system undergoes first a symmetry transmutation from a Color-Flavor-Locked (CFL) phase to a Magnetic-CFL (MCFL) phase, and then a phase transition from the MCFL phase to the Paramagnetic-CFL (PCFL) phase. The low-energy effective theory for the excitations of the diquark condensate in the presence of a magnetic field is derived using a covariant representation ...

Ferrer, E J; Ferrer, Efrain J.; Incera, Vivian de la

2007-01-01T23:59:59.000Z

119

Progress on Superconducting Magnets for the MICE Cooling Channel  

SciTech Connect (OSTI)

The muon ionization cooling experiment (MICE) consists of a target, a beam line, a pion decay channel, the MICE cooling channel. Superconducting magnets are used in the pion decay channel and the MICE cooling channel. This report describes the MICE cooling channel magnets and the progress in the design and fabrication of these magnets. The MICE cooling channel consists of three types of superconducting solenoids; the spectrometer solenoids, the coupling solenoids and the focusing solenoids. The three types of magnets are being fabricated in he United States, China, and the United Kingdom respectively. The spectrometer magnets are used to analyze the muon beam before and after muon cooling. The coupling magnets couple the focusing sections and keep the muon beam contained within the iris of the RF cavities that re used to recover the muon momentum lost during ionization cooling. The focusing magnets focus the muon beam in the center of a liquid hydrogen absorber. The first of the cooling channel magnets will be operational in MICE in the spring of 2010.

Green, Michael A; Virostek, Steve P.; Li, Derun; Zisman, Michael S.; Wang, Li; Pan, Heng; Wu, Hong; Guo, XingLong; Xu, FengYu; Liu, X. K.; Zheng, S. X.; Bradshaw, Thomas; Baynham, Elwyn; Cobb, John; Lau, Wing; Lau, Peter; Yang, Stephanie Q.

2009-09-09T23:59:59.000Z

120

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

E-Print Network [OSTI]

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

Boyer, Edmond

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

A test of a 2 Tesla superconducting transmission line magnet system  

SciTech Connect (OSTI)

Superconducting transmission line magnet test system for an injector accelerator of a staged VLHC proton-proton colliding beam accelerator has been built and operated at Fermilab. The 1.5 m long, twin-aperture, combined function dipole magnet of 2 Tesla field is excited by a single turn 100 kA transmission line superconductor. The 100 kA dc current is generated using dc-dc switching converters powered by a bulk 240 kW supply. A pair of horizontally placed conventional leads facilitates transfer of this current to the magnet transmission line superconductor operating at liquid helium temperature. Fabrication of magnet components and magnet assembly work are described. The magnet test system and its operation are presented, and the performance is summarized.

Piekarz, Henryk; Carcagno, Ruben; Claypool, Brad; Foster, George W.; Hays, Steven L.; Huang, Yuenian; Kashikhin, Vladimir; Malamud, Ernest; Mazur, Peter O.; Nehring,; Oleck, Andrew; Rabehl, Roger; Schlabach, Phil; Sylvester, Cosmore; Velev, Gueorgui; Volk, James; /Fermilab; Wake, Masayoshi; /KEK, Tsukuba

2005-09-01T23:59:59.000Z

122

Possible diminution of impurity pair breaking for triplet pairing superconductivity in two-dimensional or quasi-two-dimensional, weakly localized, nearly magnetic systems  

SciTech Connect (OSTI)

We propose a conjecture according to which, as a consequence of weak localization in two-dimensional, nearly magnetic itinerant paramagnets, the pair-breaking parameter due to normal impurity scattering, in triplet pairing superconductivity, may be reduced at low enough temperature. It might then, in principle, become easier to observe triplet pairing superconductivity in dirty two-dimensional or quasi-two-dimensional metals, than in three-dimensional ones; thus some recently observed puzzling superconductive behaviors should be reexamined.

Beal-Monod, M.T.; Ebisawa, H.; Fukuyama, H.

1984-08-01T23:59:59.000Z

123

High temperature superconducting composite conductor and method for manufacturing the same  

DOE Patents [OSTI]

A high temperature superconducting composite conductor is provided including a high temperature superconducting material surrounded by a noble metal layer, the high temperature superconducting composite conductor characterized as having a fill factor of greater than about 40. Additionally, the conductor can be further characterized as containing multiple cores of high temperature superconducting material surrounded by a noble metal layer, said multiple cores characterized as having substantially uniform geometry in the cross-sectional dimensions. Processes of forming such a high temperature superconducting composite conductor are also provided.

Holesinger, Terry G. (Los Alamos, NM); Bingert, John F. (Jemez Springs, NM)

2002-01-01T23:59:59.000Z

124

Superconducting magnetic energy storage apparatus structural support system  

DOE Patents [OSTI]

A superconducting magnetic energy storage apparatus comprising a cylindrical superconducting coil; a cylindrical coil containment vessel enclosing the coil and adapted to hold a liquid, such as liquefied helium; and a cylindrical vacuum vessel enclosing the coil containment vessel and located in a restraining structure having inner and outer circumferential walls and a floor; the apparatus being provided with horizontal compression members between (1) the coil and the coil containment vessel and (2) between the coil containment vessel and the vacuum vessel, compression bearing members between the vacuum vessel and the restraining structure inner and outer walls, vertical support members (1) between the coil bottom and the coil containment vessel bottom and (2) between the coil containment vessel bottom and the vacuum vessel bottom, and external supports between the vacuum vessel bottom and the restraining structure floor, whereby the loads developed by thermal and magnetic energy changes in the apparatus can be accommodated and the structural integrity of the apparatus be maintained.

Withers, Gregory J. (Bolingbrook, IL); Meier, Stephen W. (Bolingbrook, IL); Walter, Robert J. (Batavia, IL); Child, Michael D. (Naperville, IL); DeGraaf, Douglas W. (Downers Grove, IL)

1992-01-01T23:59:59.000Z

125

Magnetic Phenomena in Holographic Superconductivity with Lifshitz Scaling  

E-Print Network [OSTI]

We investigate the effects of Lifshitz dynamical critical exponent z on a family of minimal D=4+1 holographic superconducting models, with a particular focus on magnetic phenomena. We see that it is possible to have a consistent Ginzburg-Landau approach to holographic superconductivity in a Lifshitz background. By following this phenomenological approach we are able to compute a wide array of physical quantities. We also calculate the Ginzburg-Landau parameter for different condensates, and conclude that in systems with higher dynamical critical exponent, vortex formation is more strongly unfavored energetically and exhibit a stronger Type I behavior. Finally, following the perturbative approach proposed by Maeda, Natsuume and Okamura, we calculate the critical magnetic field of our models for different values of z.

Dector, Aldo

2015-01-01T23:59:59.000Z

126

Colour superconductivity in a strong magnetic field  

E-Print Network [OSTI]

We explore the effects of an applied strong external magnetic field in a three flavour massless colour superconductor. The long-range component of the B field that penetrates the superconductor enhances some quark condensates, leading to a different condensation pattern. The external field also reduces the flavour symmetries in the system, and thus it changes drastically the corresponding low energy physics. Our considerations are relevant for the study of highly magnetized compact stars.

Efrain J. Ferrer; Vivian de la Incera; Cristina Manuel

2005-11-30T23:59:59.000Z

127

Radiation-effects limits on copper in superconducting magnets  

SciTech Connect (OSTI)

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

128

Frustrated phase separation and high temperature superconductivity  

SciTech Connect (OSTI)

A dilute system of neutral holes in an antiferromagnet separates into a hole-rich and a hole-poor phase. The phase separation is frustrated by long-range Coulomb interactions but, provided the dielectric constant is sufficiently large, there remain large-amplitude low-energy fluctuations in the hole density at intermediate length scales. The extensive experimental evidence showing that this behavior giver, a reasonable picture of high temperature superconductors is surveyed. Further, it is shown that the scattering of mobile holes from the local density fluctuations may account for the anomalous normal-state properties of high temperature superconductors and also provide the mechanism of pairing.

Emery, V.J. [Brookhaven National Lab., Upton, NY (United States); Kivelson, S.A. [California Univ., Los Angeles, CA (United States). Dept. of Physics

1992-09-01T23:59:59.000Z

129

Frustrated phase separation and high temperature superconductivity  

SciTech Connect (OSTI)

A dilute system of neutral holes in an antiferromagnet separates into a hole-rich and a hole-poor phase. The phase separation is frustrated by long-range Coulomb interactions but, provided the dielectric constant is sufficiently large, there remain large-amplitude low-energy fluctuations in the hole density at intermediate length scales. The extensive experimental evidence showing that this behavior giver, a reasonable picture of high temperature superconductors is surveyed. Further, it is shown that the scattering of mobile holes from the local density fluctuations may account for the anomalous normal-state properties of high temperature superconductors and also provide the mechanism of pairing.

Emery, V.J. (Brookhaven National Lab., Upton, NY (United States)); Kivelson, S.A. (California Univ., Los Angeles, CA (United States). Dept. of Physics)

1992-01-01T23:59:59.000Z

130

Ab Initio Description of High-Temperature Superconductivity in Dense Molecular Hydrogen P. Cudazzo,1  

E-Print Network [OSTI]

Ab Initio Description of High-Temperature Superconductivity in Dense Molecular Hydrogen P. Cudazzo-principles study of the electron-phonon interaction and the prediction of the superconducting critical temperature superconductivity: mainly, a rich and complex Fermi surface and strongly coupled phonon modes driving the intra

Gross, E.K.U.

131

Superconducting and magnetic properties of a new EuAsFeO0.85F0.15 superconductor  

E-Print Network [OSTI]

Polycrystalline samples of a new superconducting EuAsFeO0.85F0.15 compound with critical temperature Tc=11K were prepared by solid state synthesis. Its electric and magnetic properties have been investigated in magnetic fields from 0.1 to 140000 Oe. Critical magnetic fields Hc1, and Hc2 were measured and hence the magnetic penetration depths and the coherence length have been estimated. The temperature dependence Hc2 (T) exhibits clear hyperbolic - type behavior starting with the lowest fields. The data derived were used to estimate probable high Tc and Hc2 in compounds doped with rare-earths having small atomic radii.

V. M. Dmitriev; I. E. Kostyleva; E. P. Khlybov; A. J. Zaleski; A. V. Terekhov; L. F. Rybaltchenko; E. V. Khristenko; L. A. Ishchenko

2009-01-16T23:59:59.000Z

132

Superconducting pipes and levitating magnets Yan Levin* and Felipe B. Rizzato  

E-Print Network [OSTI]

Superconducting pipes and levitating magnets Yan Levin* and Felipe B. Rizzato Instituto de Física consider the dynamics of a magnet falling coaxially through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside

Levin, Yan

133

Power applications of high-temperature superconductivity: Variable speed motors, current switches, and energy storage for end use  

SciTech Connect (OSTI)

The objective of this project is to conduct joint research and development activities related to certain electric power applications of high-temperature superconductivity (HTS). The new superconductors may allow development of an energy-efficient switch to control current to variable speed motors, superconducting magnetic energy storage (SMES) systems, and other power conversion equipment. Motor types that were considered include induction, permanent magnet, and superconducting ac motors. Because it is impractical to experimentally alter certain key design elements in radial-gap motors, experiments were conducted on an axial field superconducting motor prototype using 4 NbTi magnets. Superconducting magnetic energy storage technology with 0.25--5 kWh stored energy was studied as a viable solution to short duration voltage sag problems on the customer side of the electric meter. The technical performance characteristics of the device wee assembled, along with competing technologies such as active power line conditioners with storage, battery-based uninterruptible power supplies, and supercapacitors, and the market potential for SMES was defined. Four reports were prepared summarizing the results of the project.

Hawsey, R.A. [Oak Ridge National Lab., TN (United States); Banerjee, B.B.; Grant, P.M. [Electric Power Research Inst., Palo Alto, CA (United States)

1996-08-01T23:59:59.000Z

134

New vertical cryostat for the high field superconducting magnet test station at CERN  

SciTech Connect (OSTI)

In the framework of the R and D program for new superconducting magnets for the Large Hadron Collider accelerator upgrades, CERN is building a new vertical test station to test high field superconducting magnets of unprecedented large size. This facility will allow testing of magnets by vertical insertion in a pressurized liquid helium bath, cooled to a controlled temperature between 4.2 K and 1.9 K. The dimensions of the cryostat will allow testing magnets of up to 2.5 m in length with a maximum diameter of 1.5 m and a mass of 15 tons. To allow for a faster insertion and removal of the magnets and reducing the risk of helium leaks, all cryogenics supply lines are foreseen to remain permanently connected to the cryostat. A specifically designed 100 W heat exchanger is integrated in the cryostat helium vessel for a controlled cooling of the magnet from 4.2 K down to 1.9 K in a 3 m{sup 3} helium bath. This paper describes the cryostat and its main functions, focusing on features specifically developed for this project. The status of the construction and the plans for assembly and installation at CERN are also presented.

Vande Craen, A.; Atieh, S.; Bajko, M.; Benda, V.; Rijk, G. de; Favre, G.; Giloux, C.; Minginette, P.; Parma, V.; Perret, P.; Pirotte, O.; Ramos, D.; Viret, P. [CERN European Organization for Nuclear Research, Meyrin 1211, Geneva 23, CH (Switzerland); Hanzelka, P. [Institute of Scientific Instruments of the ASCR, Kralovopolska 147, 612 64 Brno, CZ (Czech Republic)

2014-01-29T23:59:59.000Z

135

Transformer current sensor for superconducting magnetic coils  

DOE Patents [OSTI]

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

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

1985-04-16T23:59:59.000Z

136

A Superconducting Magnet Upgrade of the ATF2 Final Focus  

SciTech Connect (OSTI)

The ATF2 facility at KEK is a proving ground for linear collider technology with a well instrumented extracted beam line and Final Focus (FF). The primary ATF2 goal is to demonstrate the extreme beam demagnification and spot stability needed for a linear collider FF. But the ATF2 FF uses water cooled magnets and the ILC baseline has a superconducting (SC) FF. We plan to upgrade ATF2 and replace some of the warm FF magnets with SC FF magnets. The ATF2 SC magnets, like the ILC FF, will made via direct wind construction. ATF2 coil winding is in progress at BNL and warm magnetic measurements indicate we have achieved good field quality. Studies indicate that having ATF2 FF magnets with larger aperture and better field quality should allow reducing the ATF2 FF beta function for study of focusing regimes relevant to CLIC. The ATF2 magnet cryostat will have laser view ports for directly monitoring cold mass movement. We plan to make stability measurements at BNL and KEK to relate ATF2 FF magnet performance to that of a full length ILC QD0 R&D FF prototype under construction at BNL.

Parker, Brett; /Brookhaven; Anerella, Michael; /Brookhaven; Escallier, John; /Brookhaven; He, Ping; /Brookhaven; Jain, Animesh; /Brookhaven; Marone, Andrew; /Brookhaven; Wanderer, Peter; /Brookhaven; Wu, Kuo-Chen; /Brookhaven; Bambade, Philip; /Orsay, LAL; Bolzon, Benoit; /Annecy, LAPP; Jeremie, Andrea; /Annecy, LAPP; Coe, Paul; /Oxford U.; Urner, David /Oxford U.; Hauviller, Claude; /CERN; Marin, Eduardo; /CERN; Tomas, Rogelio; /CERN; Zimmermann, Frank; /CERN; Kimura, Nobuhiro; /KEK, Tsukuba; Kubo, Kiyoshi; /KEK, Tsukuba; Kume, Tatsuya /KEK, Tsukuba; Kuroda, Shigeru; /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /SLAC /SLAC /SLAC

2012-07-05T23:59:59.000Z

137

A Superconducting Magnet Upgrade of the ATF2 Final Focus  

SciTech Connect (OSTI)

The ATF2 facility at KEK is a proving ground for linear collider technology with a well instrumented extracted beam line and Final Focus (FF). The primary ATF2 goal is to demonstrate the extreme beam demagnification and spot stability needed for a linear collider FF. But the ATF2 FF uses water cooled magnets and the ILC baseline has a superconducting (SC) FF. We plan to upgrade ATF2 and replace some of the warm FF magnets with SC FF magnets. The ATF2 SC magnets, like the ILC FF, will made via direct wind construction. ATF2 coil winding is in progress at BNL and warm magnetic measurements indicate we have achieved good field quality. Studies indicate that having ATF2 FF magnets with larger aperture and better field quality should allow reducing the ATF2 FF beta function for study of focusing regimes relevant to CLIC. The ATF2 magnet cryostat will have laser view ports for directly monitoring cold mass movement. We plan to make stability measurements at BNL and KEK to relate ATF2 FF magnet performance to that of a full length ILC QD0 R and D FF prototype under construction at BNL.

Parker B.; Anerella M.; Escallier J.; He P.; Jain A.; Marone A.; Wanderer P.; Wu K.C.; Hauviller C.; Marin E.; Tomas R.; Zimmermann F.; Bolzon B.; Jeremie A.; Kimura N.; Kubo K.; Kume T.; Kuroda S.; Okugi T.; Tauchi T.; Terunuma N.; Tomaru T.; Tsuchiya K.; Urakawa J.; Yamamoto A.; Bambabe P.; Coe P.; Urner D.; Seryi A.; Spencer C.; White G.

2010-05-23T23:59:59.000Z

138

Voltage spike detection in high field superconducting accelerator magnets  

SciTech Connect (OSTI)

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

139

Magnetized neutron stars with superconducting cores: Effect of entrainment  

E-Print Network [OSTI]

We construct equilibrium configurations of magnetized, two-fluid neutron stars using an iterative numerical method. We assume that the neutron star has two regions: the core, which is modelled as a two-component fluid consisting of type-II superconducting protons and superfluid neutrons, and the crust, a region composed of normal matter. Taking a new step towards more complete equilibrium models, we include the effect of entrainment, which implies that a magnetic force acts on neutrons, too. We consider purely poloidal field cases and present improvements to an earlier numerical scheme for solving equilibrium equations, by introducing new convergence criteria. We find that entrainment results in qualitative differences in the structure of field lines across the crust-core boundary and along the magnetic axis.

Palapanidis, K; Lander, S K

2015-01-01T23:59:59.000Z

140

Pseudogap The underdoped region of the temperature doping phase diagram from which cuprate superconductivity  

E-Print Network [OSTI]

superconductivity emerges is referred to as the `pseudogap' because evidence exists for partial gapping the masking effects of superconductivity. Quantum Critical Point ­ This identifies the pseudogap in YBa2Cu3O6 is such that it terminates at zero temperature inside the superconducting dome. This indicates that quantum criticality

Weston, Ken

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Superconductive Magnetic Energy Storage (SMES) System Studies for Electrical Utility at Wisconsin  

E-Print Network [OSTI]

SUPERCONDUCTIVE MAGNETIC ENERGY STORAGE (SHES) SYSTEM STUDIES FOR ELECTRICAL UTILITY USAGE AT WISCONSIN R. W. BOOM Y. M. EYSSA M. K. ABDELSALEM X. HUANG Professor Assoc. Scientist Assoc. Scientist Asst. SCientist Applied Superconductivity Center..., University of Wisconsin Madison, Wisconsin ABSTRACT Two-layer low aspect ratio rippled and non rippled solenoids mounted in surface trenches are described for superconductive magnetic energy storage utility applications. Open pool cooling...

Boom, R. W.; Eyssa, Y. M.; Abdelsalem, M. K.; Huang, X.

142

Solid-Cryogen Cooling Technique for Superconducting Magnets of NMR and MRI  

E-Print Network [OSTI]

This paper describes a solid-cryogen cooling technique currently being developed at the M.I.T. Francis Bitter Magnet Laboratory for application to superconducting magnets of NMR and MRI. The technique is particularly ...

Iwasa, Yukikazu

143

Superconducting Transitions in Wire Network under Spatially Modulated Magnetic Field  

E-Print Network [OSTI]

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

Katsumoto, Shingo

144

740 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 12, NO. 1, MARCH 2002 High-Resolution Nuclear Magnetic Resonance  

E-Print Network [OSTI]

740 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 12, NO. 1, MARCH 2002 High research depend on high- field superconducting magnets with outstanding homogeneity and excellent long term, superconducting magnets, TROSY. I. INTRODUCTION IN THE half century since its discovery, nuclear magnetic

Wider, Gerhard

145

Thermodynamic Critical Field and Superconducting Fluctuation of Vortices for High Temperature Cuprate Superconductor: La-214  

SciTech Connect (OSTI)

Thermodynamics has been studied systematically for the high temperature cuprate superconductor La{sub 2-x}Sr{sub x}CuO{sub 4-{delta}}, La-214, in the entire superconductive region from strongly underdoped to strongly overdoped regimes. Magnetization studies with H{parallel}c have been made in order to investigate the changes in free energy of the system as the number of carriers is reduced. Above the superconducting transition temperature, the normal-state magnetization exhibits a two-dimensional Heisenberg antiferromagnetic behavior. Below T{sub c}, magnetization data are thermodynamically reversible over large portions of the H-T plane, so the free energy is well defined in these regions. As the Sr concentration is varied over the wide range from 0.060 (strongly underdoped) to 0.234 (strongly overdoped), the free energy change goes through a maximum at the optimum doped in a manner similar to the T{sub c0} vs. x curve. The density of states, N(0), remains nearly constant in the overdoped and optimum doped regimes, taking a broad maximum around x = 0.188, and then drops abruptly towards zero in the underdoped regime. The La{sub 2-x}Sr{sub x}CuO{sub 4} (La-214) system displays the fluctuating vortex behavior with the characteristic of either 2D or 3D fluctuations as indicated by clearly identifiable crossing points T* close to T{sub c}. The dimensional character of the fluctuations depends on both applied magnetic fields and the density of charge carriers. The dimensional crossover from 2D to 3D occurs in the strongly underdoped regime when the c-axis coherence distance {zeta}{sub c} becomes comparable to the spacing between adjacent CuO{sub 2} layers s at sufficiently high magnetic fields near H{sub c2}.

Yung Moo Huh

2001-05-01T23:59:59.000Z

146

Thermodynamic Critical Field and Superconducting Fluctuation of Vortices for High Temperature Cuprate Superconductor: La-214  

SciTech Connect (OSTI)

Thermodynamics has been studied systematically for the high temperature cuprate superconductor La{sub 2-x}Sr{sub x}CuO{sub 4-{delta}}, La-214, in the entire superconductive region from strongly underdoped to strongly overdoped regimes. Magnetization studies with H {parallel} c have been made in order to investigate the changes in free energy of the system as the number of carriers is reduced. Above the superconducting transition temperature, the normal-state magnetization exhibits a two-dimensional Heisenberg antiferromagnetic behavior. Below T{sub c}, magnetization data are thermodynamically reversible over large portions of the H-T plane, so the free energy is well defined in these regions. As the Sr concentration is varied over the wide range from 0.060 (strongly underdoped) to 0.234 (strongly overdoped), the free energy change goes through a maximum at the optimum doped in a manner similar to the T{sub c0} vs. x curve. The density of states, N(0), remains nearly constant in the overdoped and optimum doped regimes, taking a broad maximum around x = 0.188, and then drops abruptly towards zero in the underdoped regime. The La{sub 2-x}Sr{sub x}CuO{sub 4} (La-214) system displays the fluctuating vortex behavior with the characteristic of either 2D or 3D fluctuations as indicated by clearly identifiable crossing points T* close to T{sub c}. The dimensional character of the fluctuations depends on both applied magnetic fields and the density of charge carriers. The dimensional crossover from 2D to 3D occurs in the strongly underdoped regime when the c-axis coherence distance {xi}{sub c} becomes comparable to the spacing between adjacent CuO{sub 2} layers s at sufficiently high magnetic field near H{sub c2}.

Douglas K. Finnemore

2001-06-25T23:59:59.000Z

147

On the Mechanism of Above Room Temperature Superconductivity and Superfluidity by Relativistic Quantum Mechanics  

E-Print Network [OSTI]

A comprehensive theory of superconductivity (SC) and superfluidity (SF) is presented of new types III and IV at temperatures into millions of degrees involving phase transitions of fermions in heat reservoirs to form general relativistic triple quasi-particles of 3 fermions interacting to boson-fermion pairs. Types 0, I, and II SC/SF are deduced from such triples as: thermally dressed, relativistic fermionic vortices; spin coupled, dressed, fermionic vortical pairs (diamagnetic bosons); and spinrevorbitally coupled, dressed fermionic, vortical pairs (ferromagnetic bosons). All known SC, SF and trends in critical temperatures (Tc) are thereby explained. The recently observed SC/SF in nano-graphene systems is explained. The above room temperature SC/SF is predicted and modeled by transformations of intense thermal boson populations of heat reservoirs to relativistic mass, weight, spin and magnetism for further reasoning over compression to electricity, weak phenomena and strong phenomena for connecting general relativism and quantum mechanics.

Reginald B. Little

2014-03-27T23:59:59.000Z

148

Narrowband high temperature superconducting receiver for low frequency radio waves  

DOE Patents [OSTI]

An underground communicating device has a low-noise SQUID using high temperature superconductor components connected to detect a modulated external magnetic flux for outputting a voltage signal spectrum that is related to the varying magnetic flux. A narrow bandwidth filter may be used to select a portion of the voltage signal spectrum that is relatively free of power line noise to output a relatively low noise output signal when operating in a portion of the electromagnetic spectra where such power line noise exists. A demodulator outputs a communication signal, which may be an FM signal, indicative of a modulation on the modulated external magnetic flux.

Reagor, David W. (Los Alamos, NM)

2001-01-01T23:59:59.000Z

149

Shock-induced synthesis of high temperature superconducting materials  

DOE Patents [OSTI]

It has now been determined that the unique features of the high pressure shock method, especially the shock-induced chemical synthesis technique, are fully applicable to high temperature superconducting materials. Extraordinarily high yields are achievable in accordance with this invention, e.g., generally in the range from about 20% to about 99%, often in the range from about 50% to about 90%, lower and higher yields, of course, also being possible. The method of this invention involves the application of a controlled high pressure shock compression pulse which can be produced in any conventional manner, e.g., by detonation of a high explosive material, the impact of a high speed projectile or the effect of intense pulsed radiation sources such as lasers or electron beams. Examples and a discussion are presented.

Ginley, D.S.; Graham, R.A.; Morosin, B.; Venturini, E.L.

1987-06-18T23:59:59.000Z

150

An anisotropic integral operator in high temperature superconductivity  

E-Print Network [OSTI]

A simplified model in superconductivity theory studied by P. Krotkov and A. Chubukov \\cite{KC1,KC2} led to an integral operator $K$ -- see (1), (2). They guessed that the equation $E_0(a,T)=1$ where $E_0$ is the largest eigenvalue of the operator $K$ has a solution $T(a)=1-\\tau(a)$ with $\\tau (a) \\sim a^{2/5}$ when $a$ goes to 0. $\\tau(a)$ imitates the shift of critical (instability) temperature. We give a rigorous analysis of an anisotropic integral operator $K$ and prove the asymptotic ($*$) -- see Theorem 8 and Proposition 10. Additive Uncertainty Principle (of Landau-Pollack-Slepian [SP], \\cite{LP1,LP2}) plays important role in this analysis.

Boris Mityagin

2008-03-21T23:59:59.000Z

151

Electromagnetically superconducting phase of QCD vacuum induced by strong magnetic field  

SciTech Connect (OSTI)

In this talk we discuss our recent suggestion that the QCD vacuum in a sufficiently strong magnetic field (stronger than 10{sup 16} Tesla) may undergo a spontaneous transition to an electromagnetically superconducting state. The possible superconducting state is anisotropic (the vacuum exhibits superconductivity only along the axis of the uniform magnetic field) and inhomogeneous (in the transverse directions the vacuum structure shares similarity with the Abrikosov lattice of an ordinary type-II superconductor). The electromagnetic superconductivity of the QCD vacuum is suggested to occur due to emergence of specific quark-antiquark condensates which carry quantum numbers of electrically charged rho mesons. A Lorentz-covariant generalization of the London transport equations for the magnetic-field-induced superconductivity is given.

Chernodub, M. N. [CNRS, Laboratoire de Mathematiques et Physique Theorique, Universite Francois-Rabelais Tours, Federation Denis Poisson, Parc de Grandmont, 37200 Tours (France); Department of Physics and Astronomy, University of Gent, Krijgslaan 281, S9, B-9000 Gent (Belgium)

2011-05-23T23:59:59.000Z

152

Superconducting Coherence Length and Magnetic Penetration Depth of a p-wave Holographic Superconductor  

E-Print Network [OSTI]

A classical SU(2) Einstein-Yang-Mills theory in 3+1 dimensional anti-de Sitter spacetime is believed to be dual to a p-wave superconductor in 2+1 dimensional flat spacetime. In order to calculate the superconductiong coherence length $\\xi$ of the holographic superconductor near the superconducting phase transition point, we study the perturbation of the gravity theory analytically. The superconductiong coherence length $\\xi$ is found to be proportional to $(1-T/T_c)^{-1/2}$ near the critical temperature $T_c$. We also obtain the magnetic penetration depth $\\lambda\\propto(T_c-T)^{1/2}$ by adding a small external homogeneous magnetic field. The results agree with the Ginzburg-Landau theory.

Hua-Bi Zeng; Zhe-Yong Fan; Hong-Shi Zong

2010-04-16T23:59:59.000Z

153

Method and apparatus for making superconductive magnet coils  

DOE Patents [OSTI]

A curved, shell-type magnet coil, adapted to be used in a superconducting magnet, is wound by providing a mandrel having a tubular cylindrical mid-portion terminating at both ends in tapered end portions formed with longitudinal slots having flexible fingers therebetween. An elongated electrical conductor is wound around an elongated oval-shaped pole island engaged with the outside of the cylindrical mid-portion, to form a multiplicity of oval-shaped turns engaged with a 180-degree segment of the mandrel. The coil turns have longitudinal portions with curved portions therebetween, engaging the tapered end portions of the mandrel. Upon completion of the winding, tapered expansion members are fully inserted into the tapered end portions, to displace the flexible fingers outwardly into a cylindrical form and to displace the curved portions of the turns into a shape conforming to such cylindrical form while also exerting increased tension upon the turns to minimize draping of the turns and to enhance the mechanical integrity of the coil. A half cylinder clamp may then be employed to clamp the coil, whereupon the coil may be solidified by the use of an epoxy adhesive.

Borden, A.R.

1983-11-07T23:59:59.000Z

154

From constant to non-degenerately vanishing magnetic fields in superconductivity  

E-Print Network [OSTI]

We explore the relationship between two reference functions arising in the analysis of the Ginzburg-Landau functional. The first function describes the distribution of superconductivity in a type II superconductor subjected to a constant magnetic field. The second function describes the distribution of superconductivity in a type II superconductor submitted to a variable magnetic field that vanishes non-degenerately along a smooth curve.

Bernard Helffer; Ayman Kachmar

2015-03-30T23:59:59.000Z

155

Damping and support in high-temperature superconducting levitation systems  

DOE Patents [OSTI]

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

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

2009-12-15T23:59:59.000Z

156

SUPERCONDUCTING PROPERTIES OF ALUMINIUM THIN FILMS AFTER ION IMPLANTATION AT LIQUID HELIUM TEMPERATURES (*)  

E-Print Network [OSTI]

L-271 SUPERCONDUCTING PROPERTIES OF ALUMINIUM THIN FILMS AFTER ION IMPLANTATION AT LIQUID HELIUM concentration near AlH2. It is well-known [1] that the superconducting transition temperature Tc of metals as in the electronic density of states N(O) at the Fermi surface. In the case of weak-coupling superconductors

Boyer, Edmond

157

Fermi-surface reconstruction and the origin of high-temperature superconductivity.  

SciTech Connect (OSTI)

In crystalline lattices, the conduction electrons form waves, known as Bloch states, characterized by a momentum vector k. The defining characteristic of metals is the surface in momentum space that separates occupied from unoccupied states. This 'Fermi' surface may seem like an abstract concept, but it can be measured and its shape can have profound consequences for the thermal, electronic, and magnetic properties of a material. In the presence of an external magnetic field B, electrons in a metal spiral around the field direction, and within a semiclassical momentum-space picture, orbit around the Fermi surface. Physical properties, such as the magnetization, involve a sum over these orbits, with extremal orbits on the Fermi surface, i.e., orbits with minimal or maximal area, dominating the sum [Fig. 1(a)]. Upon quantization, the resulting electron energy spectrum consists of Landau levels separated by the cyclotron energy, which is proportional to the magnetic field. As the magnetic field causes subsequent Landau levels to cross through the Fermi energy, physical quantities, such as the magnetization or resistivity, oscillate in response. It turns out that the period of these oscillations, when plotted as a function of 1/B, is proportional to the area of the extremal orbit in a plane perpendicular to the applied field [Fig. 1(b)]. The power of the quantum oscillation technique is obvious: By changing the field direction, one can map out the Fermi surface, much like a blind man feeling an elephant. The nature and topology of the Fermi surface in high-T{sub c} cuprates has been debated for many years. Soon after the materials were discovered by Bednorz and Mueller, it was realized that superconductivity was obtained by doping carriers into a parent insulating state. This insulating state appears to be due to strong electronic correlations, and is known as a Mott insulator. In the case of cuprates, the electronic interactions force the electrons on the copper ion lattice into a d{sup 9} configuration, with one localized hole in the 3d shell per copper site. Given the localized nature of this state, it was questioned whether a momentum-space picture was an appropriate description of the physics of the cuprates. In fact, this question relates to a long-standing debate in the physics community: Since the parent state is also an antiferromagnet, one can, in principle, map the Mott insulator to a band insulator with magnetic order. In this 'Slater' picture, Mott physics is less relevant than the magnetism itself. It is therefore unclear which of the two, magnetism or Mott physics, is more fundamentally tied to superconductivity in the cuprates. After twenty years of effort, definitive quantum oscillations that could be used to map the Fermi surface were finally observed in a high-temperature cuprate superconductor in 2007. This and subsequent studies reveal a profound rearrangement of the Fermi surface in underdoped cuprates. The cause of the reconstruction, and its implication for the origin of high-temperature superconductivity, is a subject of active debate.

Norman, M. R.; Materials Science Division

2010-01-01T23:59:59.000Z

158

Magnetic and superconducting phase diagrams in ErNi2B2C  

SciTech Connect (OSTI)

We present measurements of the superconducting upper critical field Hc2(T) and the magneticphasediagram of the superconductor ErNi2B2C made with a scanning tunneling microscope (STM). The magnetic field was applied in the basal plane of the tetragonal crystal structure. We have found large gapless regions in the superconductingphasediagram of ErNi2B2C, extending between different magnetic transitions. A close correlation between magnetic transitions and Hc2(T) is found, showing that superconductivity is strongly linked to magnetism.

Galvis, J.A.; Crespo, M.; Guillamon, I.; Suderow, Hermann; Vieira, S.; Garcia Hernandez, M.; Budko, Serguei; Canfield, Paul

2012-03-30T23:59:59.000Z

159

Magnetically dependent superconducting transport in oxide heterostructures with an antiferromagnetic layer  

SciTech Connect (OSTI)

The superconducting current in hybrid superconducting structures Nb/Au/Ca{sub 1-x}Sr{sub x}CuO{sub 2}/YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} with an antiferromagnetic layer is experimentally shown to have a Josephson nature, and the deviation from the sinusoidal dependence of the superconducting current on the phase difference between superconducting electrodes is about 20% of the second harmonic. These heterostructures are found to have sensitivity to an applied magnetic field that is much higher than that of conventional Josephson junctions. The experimental shape of the magnetic-field dependence of the critical current in the heterostructures differs from the usual Fraunhofer shape by oscillation with a significantly smaller period along a magnetic field.

Kislinskii, Y. V.; Konstantinian, K. Y., E-mail: karen@hitech.cplire.ru; Ovsyannikov, G. A.; Komissinskiy, P. V.; Borisenko, I. V.; Shadrin, A. V. [Russian Academy of Sciences, Institute of Radio Engineering and Electronics (Russian Federation)

2008-04-15T23:59:59.000Z

160

Quantitative Modeling of High Temperature Magnetization Dynamics  

SciTech Connect (OSTI)

Final Technical Report Project title: Quantitative Modeling of High Temperature Magnetization Dynamics DOE/Office of Science Program Manager Contact: Dr. James Davenport

Zhang, Shufeng

2009-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Above: Power deposition in the superconducting magnets and the tungsten-carbide + water shield inside them, according to a  

E-Print Network [OSTI]

Above: Power deposition in the superconducting magnets and the tungsten-carbide + water shield FOR A MUON COLLIDER (TUP265, PAC11) The concept for a muon-production system for a muon collider (or neutrino Magnet shield WC beads + water Shield must dissipate 2.4 MW Superconducting magnets tungsten-carbide (WC

McDonald, Kirk

162

Magnetic insulation at finite temperatures  

SciTech Connect (OSTI)

A finite-temperature non-neutral plasma (FTNNP) theory of magnetically insulated (MI) electron flows in crossed-field vacuum devices is developed and applied in planar geometry. It is shown that, in contrast to the single type of MI flow predicted by traditional cold-plasma treatments, the nonlinear FTNNP equations admit five types of steady flow, of which three types are MI flows, including flows in which the electric field and/or the tangential velocity at the cathode may be zero or nonzero. It is also shown that finite-temperature Vlasov-Poisson treatments yield solutions for electron number densities and electrostatic potentials that are a subset of the FTNNP solutions. The algorithms that are used to solve the FTNNP equations numerically are discussed, and the numerical results are presented for several examples of the three types of MI flow. Results include prediction of the existence, boundaries, number density profiles, and other properties of sheaths of electrons in the anode-cathode gap.

Goedecke, G. H.; Davis, Brian T.; Chen, Chiping [Physics Department, New Mexico State University, Las Cruces, New Mexico 88003 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States); Intense Beam Theoretical Research Group, Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States)

2006-08-15T23:59:59.000Z

163

To the Non-Local Theory of the High Temperature Superconductivity  

E-Print Network [OSTI]

The possibility of the non local physics application in the theory of superconductivity is investigated. It is shown that by the superconducting conditions the relay ("estafette") motion of the soliton' system ("attice ion - electron") is realizing by the absence of chemical bonds. From the position of the quantum hydrodynamics the problem of creation of the high temperature superconductors leads to finding of materials which lattices could realize the soliton' motion without destruction. These materials should be created using the technology of quantum dots. Key words: Foundations of the theory of transport processes; The theory of solitons; Generalized hydrodynamic equations; Foundations of quantum mechanics; high temperature superconductivity.

Boris V. Alexeev

2012-01-30T23:59:59.000Z

164

Transition temperatures and vacancies in superconducting Rb{sub 3}C{sub 60}  

SciTech Connect (OSTI)

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

165

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

2014-06-16T23:59:59.000Z

166

Passive Superconducting Flux Conservers for Rotating-Magnetic-Field-Driven Field-Reversed Configurations  

SciTech Connect (OSTI)

The Princeton Field-Reversed Configuration (PFRC) experiment employs an odd-parity rotating magnetic field (RMFo) current drive and plasma heating system to form and sustain high-? plasmas. For radial confinement, an array of coaxial, internal, passive, flux-conserving (FC) rings applies magnetic pressure to the plasma while still allowing radio-frequency RMFo from external coils to reach the plasma. The 3 ms pulse duration of the present experiment is limited by the skin time (?fc) of its room-temperature copper FC rings. To explore plasma phenomena with longer characteristic times, the pulse duration of the next-generation PFRC-2 device will exceed 100 ms, necessitating FC rings with (?fc > 300 ms. In this paper we review the physics of internal, discrete, passive FCs and describe the evolution of the PFRC's FC array. We then detail new experiments that have produced higher performance FC rings that contain embedded high-temperature superconducting (HTS) tapes. Several HTS tape winding configurations have been studied and a wide range of extended skin times, from 0.4 s to over 103 s, has been achieved. The new FC rings must carry up to 3 kA of current to balance the expected PFRC-2 plasma pressure, so the dependence of the HTS-FC critical current on the winding configuration and temperature was also studied. From these experiments, the key HTS-FC design considerations have been identified and HTS-FC rings with the desired performance characteristics have been produced.

E. Oz, C.E. Myers, M.R. Edwards, B. Berlinger, A. Brooks, and S.A. Cohen

2011-01-05T23:59:59.000Z

167

Transport AC loss in high temperature superconducting coils  

E-Print Network [OSTI]

be modelled. Using the original measured properties of the superconducting tape, there is an order of magnitude difference between the experiment and model. The properties of the superconductor can degrade during the winding and cooling processes, and a...

Ainslie, Mark

2012-05-08T23:59:59.000Z

168

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

SciTech Connect (OSTI)

By various theorems one can relate the capital cost of superconducting magnets to the magnetic energy stored within that magnet. This is particularly true for magnet where the cost is dominated by the structure needed to carry the magnetic forces. One can also relate the cost of the magnet to the product of the magnetic induction and the field volume. The relationship used to estimate the cost the magnet is a function of the type of magnet it is. This paper updates the cost functions given in two papers that were published in the early 1990 s. The costs (escalated to 2007 dollars) of large numbers of LTS magnets are plotted against stored energy and magnetic field time field volume. Escalated costs for magnets built since the early 1990 s are added to the plots.

Green, Mike; Green, M.A.; Strauss, B.P.

2007-08-27T23:59:59.000Z

169

The Development of Superconducting Magnets for Use in Particle Accelerators From the Tevatron to the LHC  

E-Print Network [OSTI]

Superconducting magnets have played a key role in advancing the energy reach of proton synchrotrons and enabling them to play a major role in defining the Standard Model. The problems encountered and solved at the Tevatron are described and used as an introduction to the many challenges posed by the use of this technology. The LHC is being prepared to answer the many questions beyond the Standard Model and in itself is at the cutting edge of technology. A description of its magnets and their properties is given to illustrate the advances that have been made in the use of superconducting magnets over the past 30 years.

Tollestrup, Alvin V

2008-01-01T23:59:59.000Z

170

Effective spin-flip scattering in diffusive superconducting proximity systems with magnetic disorder  

E-Print Network [OSTI]

Effective spin-flip scattering in diffusive superconducting proximity systems with magnetic superconductors and normal metals or ferromagnets with magnetic disorder. On the length scales much larger than.45. c, 75.60.Ch, 74.78.Fk I. INTRODUCTION In conventional superconductors S , pairing occurs be- tween

Skvortsov, Mikhail

171

Battery energy storage and superconducting magnetic energy storage for utility applications: A qualitative analysis  

SciTech Connect (OSTI)

This report was prepared at the request of the US Department of Energy`s Office of Energy Management for an objective comparison of the merits of battery energy storage with superconducting magnetic energy storage technology for utility applications. Conclusions are drawn regarding the best match of each technology with these utility application requirements. Staff from the Utility Battery Storage Systems Program and the superconductivity Programs at Sandia National contributed to this effort.

Akhil, A.A.; Butler, P.; Bickel, T.C.

1993-11-01T23:59:59.000Z

172

Using inhomogeneity to raise the superconducting critical temperature in a two-dimensional Y. L. Loh and E. W. Carlson  

E-Print Network [OSTI]

Using inhomogeneity to raise the superconducting critical temperature in a two-dimensional XY model, USA Received 5 February 2007; published 27 April 2007 Superconductors with low superfluid density properties such as superconductivity. That is, does inhomogeneity help or harm superconductivity

Carlson, Erica

173

Anisotropic magnetic and superconducting phase diagrams of RNi[]B[]C (R = Y, Lu, Ho)  

E-Print Network [OSTI]

system include: ~ 30 liter superinsulated helium dewar. ~ 9 Tesla superconducting magnet. ~ Cryostat probe insert assembly. ~ Sample positioning assembly with DC stepping motor control. ~ Sample probe assembly with Delrin sample cups capable... subsections to fully understand the measurement process. Figure 2 shows the cold end of the cryostat with the magnetization/magnetic susceptibility probe inserted. The outer vacuum can (another sapphire tube), not shown, as well as the 9 Tesla...

Dumar, Aaron Christopher

1999-01-01T23:59:59.000Z

174

Magnetism and superconductivity driven by identical 4f states in a heavy-fermion metal  

SciTech Connect (OSTI)

The apparently inimical relationship between magnetism and superconductivity has come under increasing scrutiny in a wide range of material classes, where the free energy landscape conspires to bring them in close proximity to each other. Particularly enigmatic is the case when these phases microscopically interpenetrate, though the manner in which this can be accomplished remains to be fully comprehended. Here, we present combined measurements of elastic neutron scattering, magnetotransport, and heat capacity on a prototypical heavy fermion system, in which antiferromagnetism and superconductivity are observed. Monitoring the response of these states to the presence of the other, as well as to external thermal and magnetic perturbations, points to the possibility that they emerge from different parts of the Fermi surface. Therefore, a single 4f state could be both localized and itinerant, thus accounting for the coexistence of magnetism and superconductivity.

Thompson, Joe E [Los Alamos National Laboratory; Nair, S [MAX PLANCK INST.; Stockert, O [MAX PLANCK INST.; Witte, U [INST. FUR FESTKORPERPHYSIK; Nicklas, M [MAX PLANCK INST.; Schedler, R [HELMHOLTZ - ZENTRUM; Bianchi, A [UC, IRVINE; Fisk, Z [UC, IRVINE; Wirth, S [MAX PLANCK INST.; Steglich, K [HELMHOLTZ - ZENTRUM

2009-01-01T23:59:59.000Z

175

Spin Torques in Magnetic and Superconducting Tunnel Junctions  

E-Print Network [OSTI]

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

Hoffman, Silas Eli

2012-01-01T23:59:59.000Z

176

Potential Applications of Microtesla Magnetic Resonance ImagingDetected Using a Superconducting Quantum Interference Device  

SciTech Connect (OSTI)

This dissertation describes magnetic resonance imaging (MRI) of protons performed in a precession field of 132 {micro}T. In order to increase the signal-to-noise ratio (SNR), a pulsed 40-300 mT magnetic field prepolarizes the sample spins and an untuned second-order superconducting gradiometer coupled to a low transition temperature superconducting quantum interference device (SQUID) detects the subsequent 5.6-kHz spin precession. Imaging sequences including multiple echoes and partial Fourier reconstruction are developed. Calculating the SNR of prepolarized SQUID-detected MRI shows that three-dimensional Fourier imaging yields higher SNR than slice-selection imaging. An experimentally demonstrated field-cycling pulse sequence and post-processing algorithm mitigate image artifacts caused by concomitant gradients in low-field MRI. The magnetic field noise of SQUID untuned detection is compared to the noise of SQUID tuned detection, conventional Faraday detection, and the Nyquist noise generated by conducting biological samples. A second-generation microtesla MRI system employing a low-noise SQUID is constructed to increase SNR. A 2.4-m cubic, eddy-current shield with 6-mm thick aluminum walls encloses the experiment to attenuate external noise. The measured noise is 0.75 fT Hz{sup -1/2} referred to the bottom gradiometer loop. Solenoids wound from 30-strand braided wire to decrease Nyquist noise and cooled by either liquid nitrogen or water polarize the spins. Copper wire coils wound on wooden supports produce the imaging magnetic fields and field gradients. Water phantom images with 0.8 x 0.8 x 10 mm{sup 3} resolution have a SNR of 6. Three-dimensional 1.6 x 1.9 x 14 mm{sup 3} images of bell peppers and 3 x 3 x 26 mm{sup 3} in vivo images of the human arm are presented. Since contrast based on the transverse spin relaxation rate (T{sub 1}) is enhanced at low magnetic fields, microtesla MRI could potentially be used for tumor imaging. The measured T{sub 1} of ex vivo normal and cancerous prostate tissue differ significantly at 132 {micro}T. A single-sided MRI system designed for prostate imaging could achieve 3 x 3 x 5 mm{sup 3} resolution in 8 minutes. Existing SQUID-based magnetoencephalography (MEG) systems could be used as microtesla MRI detectors. A commercial 275-channel MEG system could acquire 6-minute brain images with (4 mm){sup 3} resolution and SNR 16.

Myers, Whittier R.

2006-05-18T23:59:59.000Z

177

High Temperature, Permanent Magnet Biased Magnetic Bearings  

E-Print Network [OSTI]

performance, high speed and high temperature applications like space vehicles, jet engines and deep sea equipment. The bearing system had a target design to carry a load equal to 500 lb-f (2225N). Another objective was to design and build a test rig fixture...

Gandhi, Varun R.

2010-07-14T23:59:59.000Z

178

Flux penetration into superconducting Nb3Sn in oblique magnetic fields Diana G. Gheorghe, Mariela Menghini, and Rinke J. Wijngaarden  

E-Print Network [OSTI]

Flux penetration into superconducting Nb3Sn in oblique magnetic fields Diana G. Gheorghe, Mariela; published 14 June 2006 Penetration of magnetic flux into a rectangular platelet of superconducting Nb3Sn-II superconductors. For such an analysis, often the simplest solutions of the critical state problem are used, which

Wijngaarden, Rinke J.

179

Superconducting Magnet for Non-Neutral Plasma Research Alexei V. Dudarev, Victor E. Keilin, Nicolai Ph. Kopeikin, Igor O. Shugaev,  

E-Print Network [OSTI]

Superconducting Magnet for Non-Neutral Plasma Research Alexei V. Dudarev, Victor E. Keilin, Nicolai-7300 Abstract -- A superconducting magnet intended for non- neutral electron plasma research has been developed. Non-neutral plasma research is applicable to several other physics disciplines, such as two

Fajans, Joel

180

High temperature, permanent magnet biased, homopolar magnetic bearing actuator  

E-Print Network [OSTI]

current resistance and improves the system efficiency because the magnetic field of the HTPM can suspend the major portion of the static load on bearing. A high temperature radial magnetic bearing was designed via an iterative search employing 3D finite...

Hossain, Mohammad Ahsan

2006-10-30T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

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

182

ccsd00001219 Superconducting phase diagram of the lled skuterrudite PrOs 4 Sb 12  

E-Print Network [OSTI]

ccsd­00001219 (version 2) : 16 Mar 2004 Superconducting phase diagram of the #12;lled skuterrudite a precise magnetic #12;eld-temperature superconducting phase diagram of PrOs4Sb12 down to 350 mK. We discuss the superconducting phase diagram of PrOs4Sb12 and its possible relation with an unconventional superconducting order

183

Superconductivity  

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

REU participants PAGE 27 Volume 18 No. 1 * Spring 2011 Sweet Success: Ten years of hybrid magnet research PAGE 7 Ten years of hybrid magnet research PAGE 7 TABLE OF CONTENTS 7...

184

Influence of magnet size on magnetically engineered field-induced superconductivity W. Gillijns,1,* M. V. Milosevi,2,3 A. V. Silhanek,1 V. V. Moshchalkov,1, and F. M. Peeters3,  

E-Print Network [OSTI]

Influence of magnet size on magnetically engineered field-induced superconductivity W. Gillijns,1-Institute for Nanoscale Physics and Chemistry, Nanoscale Superconductivity and Magnetism and Pulsed Fields Group, K of Co/Pt magnetic disks with out-of-plane magnetization for different radii of the magnetic disks

Moshchalkov, Victor V.

185

Interplay of superconductivity and magnetism in a t-t'-J approach to high Tc cuprates  

E-Print Network [OSTI]

We review a recently proposed mechanism for superconductivity in hole-doped cuprates exhibiting a strong interplay between pairing and antiferromagnetism. Starting from the t-t'-J model for the CuO planes, we show that this interplay can explain in a unified framework the pseudogap phenomenology of the spectral weight of the hole, the hourglass-like structure of the magnetic excitation, the critical exponent of the superfluid density, the relation between the scale of the magnetic resonance and Tc.

P. A. Marchetti

2014-11-07T23:59:59.000Z

186

Weak-localization, near-magnetism, and triplet-pairing superconductivity in three dimensions  

SciTech Connect (OSTI)

In three-dimensional nearly magnetic Fermi liquids, disorder due to impurity scattering is shown to enhance the paramagnon strength and to weaken the triplet superconductivity pair-breaking parameter (through weak-localization quantum effects). As a result (a) ''heavy fermion'' superconductors are good candidates to exhibit triplet pairing and (b) normal liquid /sup 3/He can be considered as both nearly magnetic and nearly localized.

Beal-Monod, M.T.

1985-02-01T23:59:59.000Z

187

Reverse circling supercurrents along a superconducting ring  

E-Print Network [OSTI]

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

Tian De Cao

2012-01-21T23:59:59.000Z

188

The LLNL HFTF (High-Field Test Facility): A flexible superconducting test facility for fusion magnet development  

SciTech Connect (OSTI)

The High-Field Test Facility (HFTF) is a flexible and, in many ways, unique facility at Lawrence Livermore National Laboratory (LLNL) for providing the test capabilities needed to develop the superconducting magnet systems of the next generation fusion machines. The superconducting coil set in HFTF has been operated successfully at LLNL, but in its original configuration, its utility as a test facility was somewhat restricted and cryogenic losses were intolerable. A new cryostat for the coil set allows the magnet system to remain cold indefinitely so the system is available on short notice to provide high fields (about 11 T) inside a reasonably large test volume (0.3-m diam). The test volume is physically and thermally isolated from the coil volume, allowing test articles to be inserted and removed without disturbing the coil cryogenic volume, which is maintained by an on-line refrigerator. Indeed, with the proper precautions, it is even unnecessary to drop the field in the HFTF during such an operation. The separate test volume also allows reduced temperature operation without the expense and complication of subcooling the entire coil set (about 20-t cold mass). The HFTF has thus become a key facility in the LLNL magnet development program, where the primary goal is to demonstrate the technology for producing fields to 15 T with winding-pack current densities of 40 A.mm/sup -2/ in coils sized for fusion applications. 4 refs., 4 figs., 1 tab.

Miller, J.R.; Chaplin, M.R.; Leber, R.L.; Rosdahl, A.R.

1987-09-17T23:59:59.000Z

189

AB Electronic Tubes and Quasi-Superconductivity at Room Temperature  

E-Print Network [OSTI]

Author offers and researches a new idea - filling tubes by electronic gases. He shows: If the insulating envelope (cover) of the tube is charged positively, the electrons within the tube are not attracted to covering. Tube (as a whole) remains a neutral (uncharged) body. The electron gas in the tube has very low density and very high conductivity, close to superconductivity. If we take the density (pressure) of electron gas as equal to atmospheric pressure, the thickness of insulator film may be very small and the resulting tube is very light. Author shows the offered tubes can be applied to many technical fields. For example: (1) Transfer of energy over very long distance with very small electric losses. (2) Design of cheap high altitude electric lines without masts. (3) Transfer of energy from one continent to another continent through the ionosphere. (4) Transfer of a plasma beam (which can convey thrust and energy) from Earth surface to a space ship. (5) Observation of the sky by telescope without atmospheric hindrances. (6) Dirigibles (air balloons) of the highest lift force. (7) Increasing of gun range severalfold. (8) Transfer of matter. And so on. Key words: AB tubes, electronic tubes, superconductivity, transmission energy.

Alexander Bolonkin

2008-05-02T23:59:59.000Z

190

Comparative Assessment of Direct Drive High Temperature Superconducting Generators in Multi-Megawatt Class Wind Turbines  

SciTech Connect (OSTI)

This paper summarizes the work completed under the CRADA between NREL and American Superconductor (AMSC). The CRADA combined NREL and AMSC resources to benchmark high temperature superconducting direct drive (HTSDD) generator technology by integrating the technologies into a conceptual wind turbine design, and comparing the design to geared drive and permanent magnet direct drive (PMDD) wind turbine configurations. Analysis was accomplished by upgrading the NREL Wind Turbine Design Cost and Scaling Model to represent geared and PMDD turbines at machine ratings up to 10 MW and then comparing cost and mass figures of AMSC's HTSDD wind turbine designs to theoretical geared and PMDD turbine designs at 3.1, 6, and 10 MW sizes. Based on the cost and performance data supplied by AMSC, HTSDD technology has good potential to compete successfully as an alternative technology to PMDD and geared technology turbines in the multi megawatt classes. In addition, data suggests the economics of HTSDD turbines improve with increasing size, although several uncertainties remain for all machines in the 6 to 10 MW class.

Maples, B.; Hand, M.; Musial, W.

2010-10-01T23:59:59.000Z

191

PHYSICAL REVIEW B 83, 104526 (2011) Fe Mossbauer study of magnetic ordering in superconducting K0.80Fe1.76Se2.00 single crystals  

E-Print Network [OSTI]

PHYSICAL REVIEW B 83, 104526 (2011) 57 Fe M¨ossbauer study of magnetic ordering in superconducting 31 March 2011) The magnetic ordering of superconducting single crystals of K0.80Fe1.76Se2.00 has been studied between 10 and 550 K using 57 Fe M¨ossbauer spectroscopy. Despite being superconducting below Tsc

Ryan, Dominic

2011-01-01T23:59:59.000Z

192

Full-power test of a string of magnets comprising a half-cell of the Superconducting Super Collider  

SciTech Connect (OSTI)

In this paper we describe the full-powered operation of a string of industrially-fabricated magnets comprising a half-cell of the Superconducting Super Collider (SSC). The completion of these tests marks the first successful operation of a major SSC subsystem. The five 15-m long dipole magnets in the string had an aperture of 50 mm and the single 5-m long quadrupole aperture was 40 mm. Power and cryogenic connections were made to the string through spool pieces that are prototypes for SSC operations. The string was cooled to cryogenic temperatures in early July, 1992, and power tests were performed at progressively higher currents up to the nominal SSC operating point above 6500 amperes achieved in mid-August. In this paper we report on the electrical and cryogenic performance of the string components and the quench protection system during these initial tests.

Burgett, W.; Christianson, M.; Coombes, R. [and others

1992-10-01T23:59:59.000Z

193

30-MJ superconducting magnetic energy storage for electric-transmission stabilization  

SciTech Connect (OSTI)

The Bonneville Power Administration operates the electric power transmission system that connects the Pacific Northwest and southern California. The HVAC interties develop 0.35 Hz oscillations when the lines are heavily loaded. A 30 MJ (8.4 kWh) Superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter can provide system damping for the oscillation. The unit is scheduled for installation in 1982 and operation in 1982-83. Status of the project is described. The conductor has been fully tested electrically and mechanically and the 5 kA superconducting cable has been produced. The 30 MJ superconducting coil is essentially complete. All major components of the electrical and cryogenic systems except the nonconducting dewar have been completed. The refrigerator and converter are undergoing tests. The system is to be located at the BPA Tacoma Substation and operated by microwave link from Portland, OR.

Turner, R.D.; Rogers, J.D.

1981-01-01T23:59:59.000Z

194

Characterization of High Current RRP(R) Wires as a Function of Magnetic Field, Temperature and Strain  

SciTech Connect (OSTI)

A new instrument for the characterization of superconducting materials as a function of Magnetic Field, Temperature and Strain, was designed, constructed and tested at Lawrence Berkeley National Laboratory (LBNL). A U-shaped bending spring was selected, since that design has proven to enable accurate characterizations of a multitude of superconducting materials for more than a decade. The new device is validated though measurements on very high current Rod Restack Processed (RRP) Internal-Tin (IT) wires, for which we will present initial results, including parameterizations of the superconducting phase boundaries and comparisons with other wire types. Accurate parametrization of modern high magnetic field conductors is important for the analysis of the performance of magnet systems.

Godeke, A.; Mentink, M.G.T.; Dietderich, D. R.; den Ouden, A.

2009-08-16T23:59:59.000Z

195

BNL has always been a leader in the world of superconducting  

E-Print Network [OSTI]

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

196

Color superconductivity in a strong external magnetic field  

E-Print Network [OSTI]

We explore the effects of an applied strong external magnetic field in a three flavor massless color superconductor. The long-range component of the B field that penetrates the superconductor enhances some quark condensates, leading to a different condensation pattern. The external field also reduces the flavor symmetries in the system, and thus it changes drastically the corresponding low energy physics. Our considerations are relevant for the study of highly magnetized compact stars.

Cristina Manuel

2006-07-26T23:59:59.000Z

197

Magnetic field measurement of superconducting dipolemagnets with harmonic coil and Hall probe  

SciTech Connect (OSTI)

Magnetic field measurements and field analyses of 1-m long superconducting dipole magnets fabricated at the National Laboratory for High Energy Physics (KEK) have been carried out using a harmonic coil with the bucking scheme. Conditions of the data acquisition are optimized to achieve the accurate and efficient measurements. Not only in the steady state of the magnet excitation by constant currents, but also on the way the excite current increases until the magnet quenches the field measurements have been tried, and the results are discussed in this paper on the possibility of the {open_quotes}on-the-fly{close_quotes} measurement using a harmonic coil. Some results on the so-called remnant field of the magnets measured with a Hall probe are also described.

Nakai, Hirotaka; Kabe, Atsushi; Terashima, Akio [National Lab. for High Energy Physics, Tsukuba-shi, Ibaraki-ken (Japan)] [and others

1996-12-31T23:59:59.000Z

198

Quantum tunneling, quantum computing, and high temperature superconductivity  

E-Print Network [OSTI]

observed with scanning tunneling microscope (STM) in high temperature superconductors. The integrated tunneling intensities on all predominant sites have been estimated. The results can be used to test the predictions of any tight-binding model calculation...

Wang, Qian

2005-02-17T23:59:59.000Z

199

Electromagnetic Modelling of Superconducting Sensor Designs  

E-Print Network [OSTI]

transition temperature) the superconductive property of the metal disappears, and the metal behaves as a normal resistive material. Another basic feature of superconductors is the Meissner effect: magnetic flux cannot penetrate a metal in its... superconductive state apart from a very small region near the surface, where all the induced current is concentrated. If a magnetic field is applied and then the temperature decreased below Tc, flux is expelled from the bulk; if the superconductor is in the form...

Gerra, Guido

200

Superconducting magnetic control system for manipulation of particulate matter and magnetic probes in medical and industrial applications  

DOE Patents [OSTI]

A system and method of controlling movement of magnetic material with at least first and second high temperature superconductors at spaced locations. A plurality of solenoids are associated with the superconductors to induce a persistent currents in preselected high temperature superconductors establishing a plurality of magnetic fields in response to pulsed currents introduced to one or more of the solenoids. Control mechanism in communication with said solenoids and/or said high temperature superconductors are used to demagnetize selected ones of the high temperature superconductors to reduce the magnetic fields substantially to zero. Magnetic material is moved between magnetic fields by establishing the presence thereof and thereafter reducing magnetic fields substantially to zero and establishing magnetic fields in other superconductors arranged in a predetermined configuration.

Cha, Yung Sheng; Hull, John R.; Askew, Thomas R.

2006-07-11T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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.


201

Temperature relaxation in a magnetized plasma  

SciTech Connect (OSTI)

A magnetic field greatly affects the relaxation phenomena in a plasma when the particles’ thermal gyro-radii are smaller than the Debye length. Its influence on the temperature relaxation (TR) is investigated through consideration of binary collisions between charged particles in the presence of a uniform magnetic field within a perturbation theory. The relaxation times are calculated. It is shown that the electron-electron (e-e) and ion-ion (i-i) TR rates first increase and then decrease as the magnetic field grows, and the doubly logarithmic term contained in the electron-ion (e-i) TR rate results from the exchange between the electron parallel and the ion perpendicular kinetic energies.

Dong, Chao; Ren, Haijun; Cai, Huishan [Department of Modern Physics, University of Science and Technology of China, Anhui Hefei 230026 (China)] [Department of Modern Physics, University of Science and Technology of China, Anhui Hefei 230026 (China); Li, Ding [Department of Modern Physics, University of Science and Technology of China, Anhui Hefei 230026 (China) [Department of Modern Physics, University of Science and Technology of China, Anhui Hefei 230026 (China); Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2013-10-15T23:59:59.000Z

202

Dependence of the magnitude and direction of the persistent current on the magnetic flux in superconducting rings  

SciTech Connect (OSTI)

The obtained periodic magnetic-field dependences I{sub c+}({phi}/{phi}{sub 0}) and I{sub c-}({phi}/{phi}{sub 0}) of the critical current measured in opposite directions on asymmetric superconducting aluminum rings has made it possible to explain previously observed quantum oscillations of dc voltage as a result of alternating current rectification. It was found that a higher rectification efficiency of both single rings and ring systems is caused by hysteresis of the current-voltage characteristics. The asymmetry of current-voltage characteristics providing the rectification effect is due to the relative shifts of the magnetic dependences I{sub c-}({phi}/{phi}{sub 0}) = I{sub c+}({phi}/{phi}{sub 0} + {delta}{phi}) of the critical current measured in opposite directions. This shift means that the position of I{sub c+}({phi}/{phi}{sub 0}) and I{sub c-}({phi}/{phi}{sub 0}) minima does not correspond to n + 0.5 magnetic flux {phi} quanta, which is in direct contradiction to measured Little-Parks resistance oscillations. Despite this contradiction, the amplitude I{sub c,an}({phi}/{phi}{sub 0}) = I{sub c+}({phi}/{phi}{sub 0}) - I{sub c-}({phi}/{phi}{sub 0}) of critical current anisotropy oscillations and its variations with temperature correspond to the expected amplitude of persistent current oscillations and its variations with temperature.

Gurtovoi, V. L.; Dubonos, S. V.; Nikulov, A. V., E-mail: nikulov@ipmt-hpm.ac.ru; Osipov, N. N.; Tulin, V. A. [Russian Academy of Sciences, Institute of Microelectronic Technology and High-Purity Materials (Russian Federation)

2007-12-15T23:59:59.000Z

203

COMMERCIALIZATION DEMONSTRATION OF MID-SIZED SUPERCONDUCTING MAGNETIC ENERGY STORAGE TECHNOLOGY FOR ELECTRIC UTILITYAPPLICATIONS  

SciTech Connect (OSTI)

As an outgrowth of the Technology Reinvestment Program of the 1990’s, an Agreement was formed between BWXT and the DOE to promote the commercialization of Superconducting Magnetic Energy Storage (SMES) technology. Business and marketing studies showed that the performance of electric transmission lines could be improved with this SMES technology by stabilizing the line thereby allowing the reserved stability margin to be used. One main benefit sought was to double the capacity and the amount of energy flow on an existing transmission line by enabling the use of the reserved stability margin, thereby doubling revenue. Also, electrical disturbances, power swings, oscillations, cascading disturbances and brown/black-outs could be mitigated and rendered innocuous; thereby improving power quality and reliability. Additionally, construction of new transmission lines needed for increased capacity could be delayed or perhaps avoided (with significant savings) by enabling the use of the reserved stability margin of the existing lines. Two crucial technical aspects were required; first, a large, powerful, dynamic, economic and reliable superconducting magnet, capable of oscillating power flow was needed; and second, an electrical power interface and control to a transmission line for testing, demonstrating and verifying the benefits and features of the SMES system was needed. A project was formed with the goals of commercializing the technology by demonstrating SMES technology for utility applications and to establish a domestic capability for manufacturing large superconducting magnets for both commercial and defense applications. The magnet had very low AC losses to support the dynamic and oscillating nature of the stabilizing power flow. Moreover, to economically interface to the transmission line, the magnet had the largest operating voltage ever made. The manufacturing of that design was achieved by establishing a factory with newly designed and acquired equipment, tooling, methods and skilled personnel. The final magnet system measured 14 feet in diameter, 10 feet in height, and weighed about 35 tons. The superconducting magnet and design technology was successfully implemented and demonstrated. The project was not successfully concluded however; as the critical planned final demonstration was not achieved. The utilities could not understand or clarify their future business needs and the regulatory requirements, because of the deregulation policies and practices of the country. Much uncertainty existed which prevented utilities from defining business plans, including asset allocation and cost recovery. Despite the technical successes and achievements, the commercial development could not be implemented and achieved. Thus, the demonstration of this enhancement to the utility’s transmission system and to the reliability of the nation’s electrical grid was not achieved. The factory was ultimately discontinued and the technology, equipment and product were placed in storage.

CHARLES M. WEBER

2008-06-24T23:59:59.000Z

204

Proposal for the Award of a Contract for the Supply, Installation and Commissioning of Three Hydraulic Presses for the Assembly and Welding of the LHC Superconducting Dipole Magnets  

E-Print Network [OSTI]

Proposal for the Award of a Contract for the Supply, Installation and Commissioning of Three Hydraulic Presses for the Assembly and Welding of the LHC Superconducting Dipole Magnets

1998-01-01T23:59:59.000Z

205

Proposal for the Award of a Contract for the Supply, Installation and Commissioning of a Hydraulic Press for Collaring the LHC Superconducting Dipole Magnets  

E-Print Network [OSTI]

Proposal for the Award of a Contract for the Supply, Installation and Commissioning of a Hydraulic Press for Collaring the LHC Superconducting Dipole Magnets

1996-01-01T23:59:59.000Z

206

Type II superconductivity and magnetic flux transport in neutrons stars  

E-Print Network [OSTI]

The transition to a type II proton superconductor which is believed to occur in a cooling neutron star is accompanied by changes in the equation of hydrostatic equilibrium and by the formation of proton vortices with quantized magnetic flux. Analysis of the electron Boltzmann equation for this system and of the proton supercurrent distribution formed at the transition leads to the derivation of a simple expression for the transport velocity of magnetic flux in the liquid interior of a neutron star. This shows that flux moves easily as a consequence of the interaction between neutron and proton superfluid vortices during intervals of spin-down or spin-up in binary systems. The differences between the present analysis and those of previous workers are reviewed and an error in the paper of Jones (1991) is corrected.

P. B. Jones

2005-10-13T23:59:59.000Z

207

High-Tc superconductivity originated from strong spin-charge correlation: indication from linear temperature dependence of resistivity  

E-Print Network [OSTI]

Both the highest- and the linear temperature dependence of the resistivity in wide temperature range appear at the optimally doped regions of Cu-based superconductors1,2,3,4,5, and the highest- of Fe-based superconductors6,7 are also associated with the linear temperature dependence of the resistivity in normal states near superconducting states. This means that the high temperature superconductivity and the linear temperature dependence of the resistivity should be dominated by the same mechanism. This letter on theoretic calculation clearly shows that strong spin-charge correlation dominated resistivity behaves the linear temperature dependence, thus high-temperature superconductivity should be induced by strong spin-charge correlation.

Tian De Cao

2009-05-05T23:59:59.000Z

208

Beta Beams for Neutrino Production Heat Deposition from Decaying Ions in Superconducting Magnets  

E-Print Network [OSTI]

This report describes studies of energy deposition in superconducting magnets from secondary ions in the "beta beam" decay ring as described in the base-line scenario of the EURISOL Beta Beam Design Study. The lattice structure proposed in the Design Study has absorber elements inserted between the superconducting magnets to protect the magnet coils. We describe an efficient and small model made to carry out the study. The specially developed options in the beam code "ACCSIM" to track largely off-momentum particles has permitted to extract the necessary information to interface the transport and interaction code "FLUKA" with the aim to calculate the heat deposition in the magnets and the absorbers. The two beta emitters 18Ne10+ and 6He2+ used for neutrino and anti-neutrino production and their daughter ions have been tracked. The absorber system proposed in the Design Study is efficient to intercept the ions decayed in the arc straight sections as foreseen, however, the continuous decay in the dipoles induce ...

Wildner, Elena; Cerutti, F

2008-01-01T23:59:59.000Z

209

Beta Beams for neutrino production: Heat deposition from decaying ions in superconducting magnets  

E-Print Network [OSTI]

This note describes studies of energy deposition in superconducting magnets from secondary ions in the “beta beam” decay ring as described in the base-line scenario of the EURISOL Beta Beam Design Study. The lattice structure proposed in the Design Study has absorber elements inserted between the superconducting magnets to protect the magnet coils. We describe an efficient and small model made to carry out the study. The specially developed options in the beam code “ACCSIM” to track largely off-momentum particles has permitted to extract the necessary information to interface the transport and interaction code “FLUKA” with the aim to calculate the heat deposition in the magnets and the absorbers. The two beta emitters 18Ne10+ and 6He2+ used for neutrino and anti-neutrino production and their daughter ions have been tracked. The absorber system proposed in the Design Study is efficient to intercept the ions decayed in the arc straight sections as foreseen, however, the continuous decay in the dipol...

Wildner, Elena; Cerutti, Francesco

210

Magnetism and superconductivity observed to exist in harmony  

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

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211

A compact bellows-driven diamond anvil cell for high-pressure, low-temperature magnetic measurements  

SciTech Connect (OSTI)

We present the design of an efficient bellows-controlled diamond anvil cell that is optimized for use inside the bores of high-field superconducting magnets in helium-3 cryostats, dilution refrigerators, and commercial physical property measurement systems. Design of this non-magnetic pressure cell focuses on in situ pressure tuning and measurement by means of a helium-filled bellows actuator and fiber-coupled ruby fluorescence spectroscopy, respectively. We demonstrate the utility of this pressure cell with ac susceptibility measurements of superconducting, ferromagnetic, and antiferromagnetic phase transitions to pressures exceeding 8 GPa. This cell provides an opportunity to probe charge and magnetic order continuously and with high resolution in the three-dimensional Magnetic Field–Pressure–Temperature parameter space.

Feng, Yejun [The Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States) [The Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States); Silevitch, D. M.; Rosenbaum, T. F. [The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States)] [The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States)

2014-03-15T23:59:59.000Z

212

Method and apparatus for forming high-critical-temperature superconducting layers on flat and/or elongated substrates  

DOE Patents [OSTI]

An elongated, flexible superconductive wire or strip is fabricated by pulling it through and out of a melt of metal oxide material at a rate conducive to forming a crystalline coating of superconductive metal oxide material on an elongated, flexible substrate wire or strip. A coating of crystalline superconductive material, such as Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8], is annealed to effect conductive contact between adjacent crystalline structures in the coating material, which is then cooled to room temperature. The container for the melt can accommodate continuous passage of the substrate through the melt. Also, a second pass-through container can be used to simultaneously anneal and overcoat the superconductive coating with a hot metallic material, such as silver or silver alloy. A hollow, elongated tube casting method of forming an elongated, flexible superconductive wire includes drawing the melt by differential pressure into a heated tubular substrate. 8 figures.

Ciszek, T.F.

1994-04-19T23:59:59.000Z

213

Superconducting quantum interference device microsusceptometer balanced over a wide bandwidth for nuclear magnetic resonance applications  

SciTech Connect (OSTI)

Superconducting Quantum Interference Device (SQUID) microsusceptometers have been widely used to study magnetic properties of materials at microscale. As intrinsically balanced devices, they could also be exploited for direct SQUID-detection of nuclear magnetic resonance (NMR) from micron sized samples, or for SQUID readout of mechanically detected NMR from submicron sized samples. Here, we demonstrate a double balancing technique that enables achievement of very low residual imbalance of a SQUID microsusceptometer over a wide bandwidth. In particular, we can generate ac magnetic fields within the SQUID loop as large as 1 mT, for frequencies ranging from dc up to a few MHz. As an application, we demonstrate direct detection of NMR from {sup 1}H spins in a glycerol droplet placed directly on top of the 20 ?m SQUID loops.

Vinante, A., E-mail: anvinante@fbk.eu; Falferi, P. [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy); Mezzena, R. [Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento (Italy)

2014-10-15T23:59:59.000Z

214

Superconductive wire  

DOE Patents [OSTI]

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

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

1995-01-01T23:59:59.000Z

215

Testing Beam-Induced Quench Levels of LHC Superconducting Magnets in Run 1  

E-Print Network [OSTI]

In the years 2009-2013 the Large Hadron Collider (LHC) has been operated with the top beam energies of 3.5 TeV and 4 TeV per proton (from 2012) instead of the nominal 7 TeV. The currents in the superconducting magnets were reduced accordingly. To date only seventeen beam-induced quenches have occurred; eight of them during specially designed quench tests, the others during injection. There has not been a single beam- induced quench during normal collider operation with stored beam. The conditions, however, are expected to become much more challenging after the long LHC shutdown. The magnets will be operating at near nominal currents, and in the presence of high energy and high intensity beams with a stored energy of up to 362 MJ per beam. In this paper we summarize our efforts to understand the quench levels of LHC superconducting magnets. We describe beam-loss events and dedicated experiments with beam, as well as the simulation methods used to reproduce the observable signals. The simulated energy depositio...

Auchmann, B; Bednarek, M; Bellodi, G; Bracco, C; Bruce, R; Cerutti, F; Chetvertkova, V; Dehning, B; Granieri, P P; Hofle, W; Holzer, E B; Lechner, A; Del Busto, E Nebot; Priebe, A; Redaelli, S; Salvachua, B; Sapinski, M; Schmidt, R; Shetty, N; Skordis, E; Solfaroli, M; Steckert, J; Valuch, D; Verweij, A; Wenninger, J; Wollmann, D; Zerlauth, M

2015-01-01T23:59:59.000Z

216

Hall B superconducting magnets for the CLAS12 detector at JLAB  

SciTech Connect (OSTI)

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the 12 GeV upgrade is presented.

L. Quettier, V. Burkert, L. Elouadrhiri, D. Kashy, E. Leung, W. Schneider

2011-02-01T23:59:59.000Z

217

Status of Hall B superconducting magnets for the CLAS12 detector at JLab  

SciTech Connect (OSTI)

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the CLAS12 detector is presented.

Quettier, L; Kashy, D; Elouadrhiri, L; Salpietro, E; Schneider, W; Small, R; Leung, E; Juang, T; McMullin, J; Taylor, C; Xu, L; Wagner, B; Wang, B; Wang, M

2011-12-01T23:59:59.000Z

218

The US market for high-temperature superconducting wire in transmission cable applications  

SciTech Connect (OSTI)

Telephone interviews were conducted with 23 utility engineers concerning the future prospects for high-temperature superconducting (HTS) transmission cables. All have direct responsibility for transmission in their utility, most of them in a management capacity. The engineers represented their utilities as members of the Electric Power Research Institute`s Underground Transmission Task Force (which has since been disbanded). In that capacity, they followed the superconducting transmission cable program and are aware of the cryogenic implications. Nineteen of the 23 engineers stated the market for underground transmission would grow during the next decade. Twelve of those specified an annual growth rate; the average of these responses was 5.6%. Adjusting that figure downward to incorporate the remaining responses, this study assumes an average growth rate of 3.4%. Factors driving the growth rate include the difficulty in securing rights-of-way for overhead lines, new construction techniques that reduce the costs of underground transmission, deregulation, and the possibility that public utility commissions will allow utilities to include overhead costs in their rate base. Utilities have few plans to replace existing cable as preventive maintenance, even though much of the existing cable has exceeded its 40-year lifetime. Ten of the respondents said the availability of a superconducting cable with the same life-cycle costs as a conventional cable and twice the ampacity would induce them to consider retrofits. The respondents said a cable with those characteristics would capture 73% of their cable retrofits.

Forbes, D.

1996-04-01T23:59:59.000Z

219

Cryogenics Vision Workshop for High-Temperature Superconducting Electric Power Systems Proceedings  

SciTech Connect (OSTI)

The US Department of Energy's Superconductivity Program for Electric Systems sponsored the Cryogenics Vision Workshop, which was held on July 27, 1999 in Washington, D.C. This workshop was held in conjunction with the Program's Annual Peer Review meeting. Of the 175 people attending the peer review meeting, 31 were selected in advance to participate in the Cryogenics Vision Workshops discussions. The participants represented cryogenic equipment manufactures, industrial gas manufacturers and distributors, component suppliers, electric power equipment manufacturers (Superconductivity Partnership Initiative participants), electric utilities, federal agencies, national laboratories, and consulting firms. Critical factors were discussed that need to be considered in describing the successful future commercialization of cryogenic systems. Such systems will enable the widespread deployment of high-temperature superconducting (HTS) electric power equipment. Potential research, development, and demonstration (RD and D) activities and partnership opportunities for advancing suitable cryogenic systems were also discussed. The workshop agenda can be found in the following section of this report. Facilitated sessions were held to discuss the following specific focus topics: identifying Critical Factors that need to be included in a Cryogenics Vision for HTS Electric Power Systems (From the HTS equipment end-user perspective) identifying R and D Needs and Partnership Roles (From the cryogenic industry perspective) The findings of the facilitated Cryogenics Vision Workshop were then presented in a plenary session of the Annual Peer Review Meeting. Approximately 120 attendees participated in the afternoon plenary session. This large group heard summary reports from the workshop session leaders and then held a wrap-up session to discuss the findings, cross-cutting themes, and next steps. These summary reports are presented in this document. The ideas and suggestions raised during the Workshop will be used by the DOE Superconductivity Program for Electric Systems in preparing subsequent planning and strategy documents such as a Cryogenic Technology Development Roadmap.

Energetics, Inc.

2000-01-01T23:59:59.000Z

220

Low temperature laser scanning microscopy of a superconducting radio-frequency cavity  

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

An apparatus was developed to obtain, for the first time, 2D maps of the surface resistance of the inner surface of an operating superconducting radio-frequency niobium cavity by a low-temperature laser scanning microscopy technique. This allows identifying non-uniformities of the surface resistance with a spatial resolution of about one order of magnitude better than with earlier methods. A signal-to-noise ratio of about 10 dB was obtained with 240 mW laser power and 1 Hz modulation frequency. The various components of the apparatus, the experimental procedure and results are discussed in details in this contribution.

Ciovati, Gianluigi; Baldwin, Charles; Cheng, Guangfeng; Flood, Roger; Jordan, Kevin; Kneisel, Peter; Morrone, Michael; Nemes, George; Turlington, Larry; Wang, Haipeng; Wilson, Katherine

2012-03-16T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Rheological behavior and cryogenic properties of cyanate ester/epoxy insulation material for fusion superconducting magnet  

SciTech Connect (OSTI)

In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical properties of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.

Wu, Z. X.; Huang, C. J. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR (China); Li, L. F. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, C (China); Li, J. W. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and University of Chinese Academy of Sciences, Beijing 100049, PR (China); Tan, R.; Tu, Y. P. [North China Electric Power University, Beijing 102206, PR (China)

2014-01-27T23:59:59.000Z

222

Equilibrium intermediate-state patterns in a type-I superconducting slab in an arbitrarily oriented applied magnetic field  

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

The equilibrium topology of superconducting and normal domains in flat type-I superconductors is investigated. Important improvements with respect to previous work are that (1) the energy of the external magnetic field, as deformed by the presence of superconducting domains, is calculated in the sameway for three different topologies and (2) calculations are made for arbitrary orientation of the applied field. A phase diagram is presented for the minimum-energy topology as a function of applied field magnitude and angle. For small (large) applied fields, normal (superconducting) tubes are found, while for intermediate fields, parallel domains have a lower energy. The range of field magnitudes for which the superconducting-tubes structure is favored shrinks when the field is more in-plane oriented.

None

2013-09-04T23:59:59.000Z

223

Superconducting vortex pinning with artificially prepared nanostructures  

E-Print Network [OSTI]

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

Rosen, Yaniv Jacob

224

Method for determining hydrogen mobility as a function of temperature in superconducting niobium cavities  

DOE Patents [OSTI]

A method for determining the mobility of hydrogen as a function of temperature in superconducting niobium cavities comprising: 1) heating a cavity under test to remove free hydrogen; 2) introducing hydrogen-3 gas into the cavity; 3) cooling the cavity to allow absorption of hydrogen-3; and 4) measuring the amount of hydrogen-3 by: a) cooling the cavity to about 4.degree. K while flowing a known and regulated amount of inert carrier gas such as argon or helium into the cavity; b) allowing the cavity to warm at a stable rate from 4.degree. K to room temperature as it leaves the chamber; and c) directing the exit gas to an ion chamber radiation detector.

May, Robert (Virginia Beach, VA)

2008-03-11T23:59:59.000Z

225

Experience with operation of a large magnet system in the international fusion superconducting magnet test facility  

SciTech Connect (OSTI)

Superconducting toroidal field systems, including coils and ancillaries, are being developed through international collaboration in the Large Coil Task. Focal point is a test facility in Oak Ridge where six coils will be tested in a toroidal array. Shakedown of the facility and preliminary tests of the first three coils (from Japan, Switzerland, and the US) were accomplished in 1984. Useful data were obtained on performance of the helium refrigerator and distribution system, power supplies, control and data acquisition systems and voltages, currents, strains, and acoustic emission in the coils. Performance was generally gratifying except for the helium system, where improvements are being made.

Fietz, W.A.; Ellis, J.F.; Haubenreich, P.N.; Schwenterly, S.W.; Stamps, R.E.

1985-01-01T23:59:59.000Z

226

New superconducting toroidal magnet system for IAXO, the international AXion observatory  

SciTech Connect (OSTI)

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

227

Statistical factors to qualify the superconducting magnets for the SSC based on warm/cold correlations  

SciTech Connect (OSTI)

All of the SSC production magnets will be measured at room temperature (warm), but only a fraction of these will be measured at liquid helium temperature (cold). The fractional information will then be analyzed to determine warm acceptance criteria for the field quality of the SSC magnets. Regarding predictors of the field quality based on partial information, there are several observations and studies based on the warm/cold correlation. A different facet of the acceptance test is production control, which interprets the warm/cold correlation to adjust the process parameters. For these applications, we are evaluating statistical techniques relying on asymptotic estimators of the systematic errors and random errors, and their respective confidence intervals. The estimators are useful to qualify the population magnets based on a subset of sample magnets. We present the status of our work, including: (i) a recapitulation of analytic formulas, (ii) a justification based on HERA magnet experience, and (iii) a practical interpretation of these estimators.

Kim, K.; Devred, A.; Coles, M.; Tompkins, J.

1993-05-01T23:59:59.000Z

228

Design of a magnetic shielding system for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak  

SciTech Connect (OSTI)

The novel neutron spectrometer TOFED (Time of Flight Enhanced Diagnostics), comprising 90 individual photomultiplier tubes coupled with 85 plastic scintillation detectors through light guides, has been constructed and installed at Experimental Advanced Superconducting Tokamak. A dedicated magnetic shielding system has been constructed for TOFED, and is designed to guarantee the normal operation of photomultiplier tubes in the stray magnetic field leaking from the tokamak device. Experimental measurements and numerical simulations carried out employing the finite element method are combined to optimize the design of the magnetic shielding system. The system allows detectors to work properly in an external magnetic field of 200 G.

Cui, Z. Q.; Chen, Z. J.; Xie, X. F.; Peng, X. Y.; Hu, Z. M.; Du, T. F.; Ge, L. J.; Zhang, X.; Yuan, X.; Fan, T. S.; Chen, J. X.; Li, X. Q., E-mail: lixq2002@pku.edu.cn, E-mail: guohuizhang@pku.edu.cn; Zhang, G. H., E-mail: lixq2002@pku.edu.cn, E-mail: guohuizhang@pku.edu.cn [School of Physics, State Key Lab of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Xia, Z. W. [Southwestern Institute of Physics, Chengdu 610225 (China); Hu, L. Q.; Zhong, G. Q.; Lin, S. Y.; Wan, B. N. [Institute of Plasma Physics, CAS, Hefei 230031 (China)

2014-11-15T23:59:59.000Z

229

Presented at the Applied Superconductivity Conference at Houston, TX, August 4-9, 2002 BNL-Magnet Engineering and Test Results of the  

E-Print Network [OSTI]

Magnet Engineering and Test Results of the High Field Magnet R&D Program at BNL J. Cozzolino, M. Anerella about ten years from now. This paper presents the engineering design of a "react and wind" Nb3Sn magnet. Parker, W. Sampson, R. Soika, and P. Wanderer Abstract--The Superconducting Magnet Division at Brookhaven

Gupta, Ramesh

230

Temperature dependent nucleation and annihilation of individual magnetic vortices.  

SciTech Connect (OSTI)

We studied the temperature dependence of the magnetization reversal in individual submicron permalloy disks with micro-Hall and bend-resistance magnetometry. The nucleation field exhibits a nonmonotonic dependence with positive and negative slopes at low and high temperatures, respectively, while the annihilation field monotonically decreases with increasing temperature, but with distinctly different slopes at low and high temperatures. Our analysis suggests that at low temperatures vortex nucleation and annihilation proceeds via thermal activation over an energy barrier, while at high temperatures they are governed by a temperature dependence of the saturation magnetization.

Mihajlovic, G.; Patrick, M. S.; Pearson, J. E.; Novosad, V.; Bader, S. D.; Field, M.; Sullivan, G. J.; Hoffmann, A.; Teledyne Scientific Co., LLC

2010-03-15T23:59:59.000Z

231

Real-Time Capable Methods to Determine the Magnet Temperature of Permanent Magnet  

E-Print Network [OSTI]

}@lea.upb.de Abstract--The permanent magnet synchronous motor (PMSM) is widely used in highly utilised automotive-based magnet temperature determination methods in PMSM. In this context, the existing publications can field. Keywords--PMSM, permanent magnet temperature, model- based real-time determination, motor control

Paderborn, Universität

232

Low temperature magnetic transitions of single crystal HoBi  

SciTech Connect (OSTI)

We present resistivity, specific heat and magnetization measurements in high quality single crystals of HoBi, with a residual resistivity ratio of 126. We find, from the temperature and field dependence of the magnetization, an antiferromagnetic transition at 5.7 K, which evolves, under magnetic fields, into a series of up to five metamagnetic phases.

Fente, A. [Universidad Autonoma de Madrid; Suderow, H. [Universidad Autonoma de Madrid; Vieira, S. [Universidad Autonoma de Madrid; Nemes, N. M. [Instituto de Ciencia de Materiales de Madrid; Garcia-Hernandez, M. [Instituto de Ciencia de Materiales de Madrid; Budko, Sergei L. [Ames Laboratory; Canfield, Paul C. [Ames Laboratory

2013-09-04T23:59:59.000Z

233

Phase-Boundary of several Multicube Superconducting Circuits in a Magnetic-Field of Arbitrary Magnitude and Direction  

E-Print Network [OSTI]

of this study ?although we did not provide a rigorous proof ?is that the phase boundary T, (H) of an infinite three dim-ensional superconducting network is a continuous fractal hypersurface in four dimensions, i.e., in the space of (T?H?,H, H, ) or (T...?H,a,P). This con- clusion is actually an expected generalization of the well- known result for some time that the phase boundary T, (H) of a two dimens-ional infinite superconducting net- work in a perpendicular magnetic field H is a continuous fractal curve...

YI, YM; Hu, Chia-Ren.

1992-01-01T23:59:59.000Z

234

Thermal Performance of the Supporting System for the Large Hadron Collider (LHC) Superconducting Magnets  

E-Print Network [OSTI]

The LHC collider will be composed of approximately 1700 main ring superconducting magnets cooled to 1.9 K in pressurised superfluid helium and supported within their cryostats on low heat in-leak column-type supports. The precise positioning of the heavy magnets and the stringent thermal budgets imposed by the machine cryogenic system, require a sound thermo-mechanical design of the support system. Each support is composed of a main tubular thin-walled structure in glass-fibre reinforced epoxy resin, with its top part interfaced to the magnet at 1.9 K and its bottom part mounted onto the cryostat vacuum vessel at 293 K. In order to reduce the conduction heat in-leak at 1.9 K, each support mounts two heat intercepts at intermediate locations on the column, both actively cooled by cryogenic lines carrying helium gas at 4.5-10 K and 50-65 K. The need to assess the thermal performance of the supports has lead to setting up a dedicated test set-up for precision heat load measurements on prototype supports. This pa...

Castoldi, M; Parma, Vittorio; Vandoni, Giovanna

1999-01-01T23:59:59.000Z

235

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

236

DESIGN OF SUPERCONDUCTING COMBINED FUNCTION MAGNETS FOR THE 50 GEV PROTON BEAM LINE FOR THE J-PARC NEUTRINO EXPERIMENT.  

SciTech Connect (OSTI)

Superconducting combined function magnets will be utilized for the 50GeV-750kW proton beam line for the J-PARC neutrino experiment and an R and D program has been launched at KEK. The magnet is designed to provide a combined function with a dipole field of 2.59 T and a quadrupole field of 18.7 T/m in a coil aperture of 173.4 mm. A single layer coil is proposed to reduce the fabrication cost and the coil arrangement in the 2-D cross-section results in left-right asymmetry. This paper reports the design study of the magnet.

WANDERER,P.; ET AL.

2003-06-15T23:59:59.000Z

237

Effect of temperature on phonon contribution to Green function of high-temperature superconducting cuprates  

SciTech Connect (OSTI)

The phonon contribution to the nodal electron Green function in cuprates is considered. It is shown that the temperature dependence of the real part of the self-energy component of the Green function for cuprates with a hole doping level close to optimal is described by the electron-phonon interaction in the framework of the extended Eliashberg model.

Korneeva, L. A., E-mail: korneeva_mila@mail.ru; Mazur, E. A. [National Research Nuclear University MEPhI (Russian Federation)

2012-08-15T23:59:59.000Z

238

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

E-Print Network [OSTI]

107 Figure IV.3: Electrical resistance R vs. temperature TRoom-temperature electrical resistance vs. applied load andanvil cell (DAC) electrical resistivity vs. temperature for

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

239

Contribution of ion beam analysis methods to the development of 2nd generation high temperature superconducting (HTS) wires  

SciTech Connect (OSTI)

One of the crucial steps in the second generation high temperature superconducting wire program was development of the buffer layer architecture. The architecture designed at the Superconductivity Technology Center at Los Alamos National Laboratory consists of several oxide layers wherein each layer plays a specific role, namely: nucleation layer, diffusion barrier, biaxially textured template, and an intermediate layer with a good match to the lattice parameter of superconducting Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} (YBCO) compound. This report demonstrates how a wide range of ion beam analysis techniques (SIMS, RBS, channeling, PIXE, PIGE, NRA, ERD) was employed for analysis of each buffer layer and the YBCO films. These results assisted in understanding of a variety of physical processes occurring during the buffet layer fabrication and helped to optimize the buffer layer architecture as a whole.

Usov, Igor O [Los Alamos National Laboratory; Arendt, Paul N [Los Alamos National Laboratory; Stan, Liliana [Los Alamos National Laboratory; Holesinger, Terry G [Los Alamos National Laboratory; Foltyn, Steven R [Los Alamos National Laboratory; Depaula, Raymond F [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

240

Control of magnetic, nonmagnetic, and superconducting states in annealed Ca(Fe1?xCox)2As2  

SciTech Connect (OSTI)

We have grown single-crystal samples of Co substituted CaFe2As2 using an FeAs flux and systematically studied the effects of annealing/quenching temperature on the physical properties of these samples. Whereas the as-grown samples (quenched from 960 ?C) all enter the collapsed tetragonal phase upon cooling, annealing/quenching temperatures between 350 and 800 ?C can be used to tune the system to low-temperature antiferromagnetic/orthorhomic or superconducting states as well. The progression of the transition temperature versus annealing/quenching temperature (T-Tanneal) phase diagrams with increasing Co concentration shows that, by substituting Co, the antiferromagnetic/orthorhombic and the collapsed tetragonal phase lines are separated and bulk superconductivity is revealed. We established a 3D phase diagram with Co concentration and annealing/quenching temperature as two independent control parameters. At ambient pressure, for modest x and Tanneal values, the Ca(Fe1?xCox)2As2 system offers ready access to the salient low-temperature states associated with Fe-based superconductors: antiferromagnetic/orthorhombic, superconducting, and nonmagnetic/collapsed tetragonal.

Ran, Sheng; Budko, Serguei L.; Straszheim, Warren E.; Soh, Jing-Han; Kim, Min Gyu; Kreyssig, Andreas; Goldman, Alan I.; Canfield, Paul C.

2012-06-22T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Control of magnetic, nonmagnetic, and superconducting states in annealed Ca(Fe1–xCox)?As?  

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

We have grown single-crystal samples of Co substituted CaFe?As? using an FeAs flux and systematically studied the effects of annealing/quenching temperature on the physical properties of these samples. Whereas the as-grown samples (quenched from 960°C) all enter the collapsed tetragonal phase upon cooling, annealing/quenching temperatures between 350 and 800°C can be used to tune the system to low-temperature antiferromagnetic/orthorhomic or superconducting states as well. The progression of the transition temperature versus annealing/quenching temperature (T-Tanneal) phase diagrams with increasing Co concentration shows that, by substituting Co, the antiferromagnetic/orthorhombic and the collapsed tetragonal phase lines are separated and bulk superconductivity is revealed. We established a 3D phase diagram with Co concentration and annealing/quenching temperature as two independent control parameters. At ambient pressure, for modest x and Tanneal values, the Ca(Fe??xCox)?As? system offers ready access to the salient low-temperature states associated with Fe-based superconductors: antiferromagnetic/orthorhombic, superconducting, and nonmagnetic/collapsed tetragonal.

Ran, S.; Bud'ko, S. L.; Straszheim, W. E.; Soh, J.; Kim, M. G.; Kreyssig, A.; Goldman, A. I.; Canfield, P. C.

2012-06-01T23:59:59.000Z

242

MODELING OF EDDY CURRENT LOSS AND TEMPERATURE OF THE MAGNETS  

E-Print Network [OSTI]

the performance of the machine. This paper presents the modeling and analysis of eddy current loss in surfaceMODELING OF EDDY CURRENT LOSS AND TEMPERATURE OF THE MAGNETS IN PERMANENT MAGNET MACHINES ¤ XIAOFENG DING Electrical Engineering Department, Northwestern Polytechnical University, 127 Youyi Xilu #352

Mi, Chunting "Chris"

243

Stability and quench protection of high-temperature superconductors  

E-Print Network [OSTI]

In the design and operation of a superconducting magnet, stability and protection are two key issues that determine the magnet's reliability and safe operation. Although the high-temperature superconductor (HTS) is considered ...

Ang, Ing Chea

2006-01-01T23:59:59.000Z

244

Engineering Division Superconducting  

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

& Engineering Division Superconducting Magnet Technology for Fusion and Large Scale Applications Joseph V. Minervini Massachusetts Institute of Technology Plasma Science and Fusion...

245

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

E-Print Network [OSTI]

1.3 Magnetism . . . . .1.3.3 Itinerant Magnetism . . . . . . . . . . .3.3 Magnetism . . . . . . . . . . . . . . . . . . . . . 3.4

Sayles, Todd Allen

2008-01-01T23:59:59.000Z

246

Configuration and temperature dependence of magnetic damping in spin valves  

SciTech Connect (OSTI)

Using vector-analyzer ferromagnetic resonance, we have studied the microwave susceptibility of a Py/Co/Cu/Co/MnIr spin valve over a large temperature range (5-450 K) and as a function of the magnetic configuration. An effective magnetization and Gilbert damping constant of 1.1 T and 0.021, respectively, are found for the permalloy free layer, with no discernible variation in temperature observed for either quantities. In contrast, the pinned layer magnetization is reduced by heating, and the exchange bias collapses near a temperature of 450 K. The ferromagnetic resonance linewidth of the free layer increases by 500 MHz when the layer magnetizations are aligned in antiparallel, which is attributed to a configuration-dependent contribution to the damping from spin pumping effects.

Joyeux, X.; Devolder, T.; Kim, Joo-Von; Gomez de la Torre, Y.; Eimer, S.; Chappert, C. [Institut d'Electronique Fondamentale, University Paris-Sud, 91405 Orsay (France); UMR8622, CNRS, University Paris-Sud, 91405 Orsay (France)

2011-09-15T23:59:59.000Z

247

Investigating the relationship between the superconducting and pseudogap states of the high-temperature superconductor Bi-2201 using scanning tunneling microscopy  

E-Print Network [OSTI]

There is considerable controversy regarding the nature of the relationship between the superconducting and pseudogap states of high-temperature superconductors. Although there exist a large number of theories regarding ...

Boyer, Michael Christopher

2008-01-01T23:59:59.000Z

248

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

E-Print Network [OSTI]

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

Dizon, Jonathan Reyes

2009-04-28T23:59:59.000Z

249

Superconducting microfabricated ion traps  

E-Print Network [OSTI]

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

Wang, Shannon Xuanyue

250

Realization of a superconducting atom chip  

E-Print Network [OSTI]

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

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

2006-10-09T23:59:59.000Z

251

Above: On-axis field profiles of resistive, superconducting and all magnets, and bore-tube radius r = 7.5 (B/20T)- cm.  

E-Print Network [OSTI]

MAGNET SYSTEM FOR A MUON COLLIDER AND NEUTRINO FACTORY (TUPS053, IPAC11) The concept for a muon-production filled with tungsten-carbide pellets (~ 60% by volume, cooled by water) attenuate the radiation issuing.4 MW Superconducting magnets tungsten-carbide (WC) beads + water tungsten-carbide beads + water proton

McDonald, Kirk

252

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

SciTech Connect (OSTI)

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

253

Methods to detect faulty splices in the superconducting magnet system of the LHC  

SciTech Connect (OSTI)

The incident of 19 September 2008 at the LHC was caused by a faulty inter-magnet splice of about 200 n{Omega} resistance. Cryogenic and electrical techniques have been developed to detect other abnormal splices, either between or inside the magnets. The existing quench protection system can be used to detect internal splices with R > 20 n{Omega}. Since this system does not cover the bus between magnets, the cryogenic system is used to measure the rate of temperature rise due to ohmic heating. Accuracy of a few mK/h, corresponding to a few Watts, has been achieved, allowing detection of excess resistance, if it is more than 40 n{Omega} in a cryogenic subsector (two optical cells). Follow-up electrical measurements are made in regions identified by the cryogenic system. These techniques have detected two abnormal internal magnet splices of 100 n{Omega} and 50 n{Omega} respectively. In 2009, this ad hoc system will be replaced with a permanent one to monitor all splices at the n{Omega} level.

Bailey, R.; Bellesia, B.; Lasheras, N.Catalan; Dahlerup-Petersen, K.; Denz, R.; Robles, C.; Koratzinos, M.; Pojer, M.; Ponce, L.; Saban, R.; Schmidt, R.; /CERN /Fermilab /Moscow, INR /Cracow, INP

2009-05-01T23:59:59.000Z

254

Superconducting vortex pinning with artificially prepared nanostructures  

E-Print Network [OSTI]

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

Rosen, Yaniv Jacob

255

Magnetically polarized Ir dopant atoms in superconducting Ba(Fe1?xIrx)2As2  

SciTech Connect (OSTI)

We investigate the magnetic polarization of the Ir 5d dopant states in the pnictide superconductor Ba(Fe1?xIrx)2As2 with x=0.027(2) using Ir L3 edge x-ray resonant magnetic scattering (XRMS). Despite the fact that doping partially suppresses the antiferromagnetic transition, we find that magnetic order survives around the Ir dopant sites. The Ir states are magnetically polarized with commensurate stripe-like antiferromagnetic order and long correlations lengths, ?mag>2800 and >850 Å, in the ab plane and along the c axis, respectively, driven by their interaction with the Fe spins. This Ir magnetic order persists up to the Néel transition of the majority Fe spins at TN=74(2) K. At 5 K we find that magnetic order coexists microscopically with superconductivity in Ba(Fe1?xIrx)2As2. The energy dependence of the XRMS through the Ir L3 edge shows a non-Lorentzian line shape, which we explain in terms of interference between Ir resonant scattering and Fe nonresonant magnetic scattering.

Dean, M.P.M.; Kim, M.G.; Kreyssig, A.; Kim, J.W.; Liu, X.; Ryan, P.J.; Thaler, A.; Budko, S.L.; Strassheim, W.; Canfield, P.C.; Hill, J.P.; Goldman, A.I.

2012-04-25T23:59:59.000Z

256

Study on effect of annealing conditions on structural, magnetic and superconducting properties of MgB{sub 2} bulk samples  

SciTech Connect (OSTI)

Effect of annealing conditions on structural, magnetic and superconducting properties of Magnesium Diboride (MgB{sub 2}) bulk superconductor samples prepared by solid state route method are compared. The samples are made by taking Magnesium and Boron powders in stoichiometric ratio, grounded well and pelletized at pressure of about 10Tonnes. These pellets are annealed in both Argon and vacuum environment separately up to 800°c for two hours. Both the samples show clear superconducting transition at Tc ? 38 k. This is further conformed by AC/DC magnetization (M-T), Resistivity [? (T, H)] measurements under magnetic field up to 14 Tesla as well. Rietveld refinement of X-ray diffraction of both samples conformed the MgB{sub 2} phase formation with P6/mmm space group symmetry. Scanning Electron Microscopy images of the surface revile more agglomeration of grains in case of Argon annealed samples. This result in more critical current density (J{sub c}) of Argon annealed samples than vacuum annealed one calculated from Bean's critical state model. This high Jc is explained in terms of more inter grain connectivity for Argon annealed sample than vacuum annealed sample.

Phaneendra, Konduru, E-mail: phaneendra-50@yahoo.com; Asokan, K., E-mail: phaneendra-50@yahoo.com; Kanjilal, D. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, Vasanth Kung, New Delhi-110067 (India); Awana, V. P. S. [Quantum Phenomena and Applications, National Physical Laboratory, K S Krishnan Marg, New Delhi-110012 (India); Sastry, S. Sreehari [Dept. of Physics, Acharya Nagarjuna University, Guntur-522510 (India)

2014-04-24T23:59:59.000Z

257

Preparation of high temperature superconducting coated wires by dipping and post annealing  

SciTech Connect (OSTI)

This patent describes a process for coating a film on a wire substrate, it comprises: melting a superconducting metal oxide mixture in a crucible to form a melt; coating the substrate with a diffusion barrier; dipping the coated wire substrate into the melt; cooling the coated wire substrate at a rate sufficiently slow to avoid thermal shock and hot cracking; and post-annealing the cooled, coated wire substrate to relieve thermal stresses in the coating, whereupon the superconducting metal-oxide mixture forms a perovskite coating upon the wire substrate.

Provenzano, V.; Singh, A.K.; Imam, M.A.; Tritt, T.M.

1992-04-14T23:59:59.000Z

258

Increased superconducting transition temperature of a niobium thin-film proximity-coupled to gold nanoparticles using linking organic molecules  

E-Print Network [OSTI]

The superconducting critical temperature, TC, of thin Nb films is significantly modified when gold nanoparticles (NPs) are chemically linked to the Nb film, with a consistent enhancement when using 3 nm long disilane linker molecules. The TC increases by up to 10% for certain linker length and NPs size. No change is observed when the nanoparticles are physisorbed with non-linking molecules. Electron tunneling spectra acquired on the linked NPs below TC typically exhibit zero-bias peaks. We attribute these results to a pairing mechanism coupling electrons in the Nb and the NPs, mediated by the organic linkers.

Eran Katzir; Shira Yochelis; Felix Zeides; Nadav Katz; Yoav Kalcheim; Oded Millo; Gregory Leitus; Yuri Myasodeyov; Boris Ya. Shapiro; Ron Naaman; Yossi Paltiel

2011-11-02T23:59:59.000Z

259

Simulations of magnetic hysteresis loops at high temperatures  

SciTech Connect (OSTI)

The kinetic Monte-Carlo algorithm as well as standard micromagnetics are used to simulate MH loops of high anisotropy magnetic recording media at both short and long time scales over a wide range of temperatures relevant to heat-assisted magnetic recording. Microscopic parameters, common to both methods, were determined by fitting to experimental data on single-layer FePt-based media that uses the Magneto-Optic Kerr effect with a slow sweep rate of 700?Oe/s. Saturation moment, uniaxial anisotropy, and exchange constants are given an intrinsic temperature dependence based on published atomistic simulations of FePt grains with an effective Curie temperature of 680?K. Our results show good agreement between micromagnetics and kinetic Monte Carlo results over a wide range of sweep rates. Loops at the slow experimental sweep rates are found to become more square-shaped, with an increasing slope, as temperature increases from 300?K. These effects also occur at higher sweep rates, typical of recording speeds, but are much less pronounced. These results demonstrate the need for accurate determination of intrinsic thermal properties of future recording media as input to micromagnetic models as well as the sensitivity of the switching behavior of thin magnetic films to applied field sweep rates at higher temperatures.

Plumer, M. L.; Whitehead, J. P.; Fal, T. J. [Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador A1B 3X7 (Canada); Ek, J. van [Western Digital Corporation, San Jose, California 94588 (United States); Mercer, J. I. [Department of Computer Science, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador A1B 3X7 (Canada)

2014-09-28T23:59:59.000Z

260

Influence of the inductor shape, and the magnetization processes on a trapped magnetic flux in a superconducting  

E-Print Network [OSTI]

, the maximum value of remnant magnetic induction in a permanent magnet is about 1.5 Tesla for Nd where we have enough space (e.g. magnetic coupling, and axial motors applications) and the need

Boyer, Edmond

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Superconductive imaging surface magnetometer  

DOE Patents [OSTI]

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

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

1991-01-01T23:59:59.000Z

262

Shrink Tube Insulation Apparatus for Rebco Superconducting Tapes for Use in High Field Magnets  

E-Print Network [OSTI]

An increasing number of applications require the use of high temperature superconductors (HTS) such as (RE=Rare Earth) Ba2Cu3O7-x (REBCO) coated conductors [1]. HTS conductors show particularly great potential for high field magnets applications [1] due to their high upper critical fields [2], But several groups have shown that REBCO coated conductors are prone to delamination failure [3] [4] [5]. Under relatively low transverse stress the HTS film separates from the substrate and the conductor degrades [6]. This is problematic due to high transverse stresses that occur in fully epoxy impregnated solenoids wound with this conductor. Application of thin walled heat shrink tubing introduces a weak plane around the conductor, preventing delamination degradation [7]. However, manual application of the shrink tubing is impractical, requiring three operators limited to insulating 100 m lengths or less of REBCO conductor. The high risk of damage to the conductor, also associated with this process, shows the need for...

Whittington, Andrew

263

Fusion Engineering and Design 7579 (2005) 2932 First integrated test of the superconducting magnet systems  

E-Print Network [OSTI]

Fusion Engineering and Design 75­79 (2005) 29­32 First integrated test of the superconducting of Applied Physics and Applied Mathematics Room 210 S.W., Mudd Building, New York, NY 10027, USA Available at the center of a 5 m diameter, 3 m tall vacuum chamber. The Floating coil (F-coil) is designed for a maximum

264

Superconductivity: the Gift that Keeps on Giving  

E-Print Network [OSTI]

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

Goldberg, Bennett

265

Selected room temperature magnetic parameters as a function of mineralogy, concentration and grain size  

E-Print Network [OSTI]

Selected room temperature magnetic parameters as a function of mineralogy, concentration and grain literature. The aim was to propose the most effective methods for assessing mineralogy, concentration and domain state within environmental magnetic studies. Establishing the magnetic mineralogy is essential

Utrecht, Universiteit

266

Cryostat design and analysis of the superconducting magnets for Jefferson Lab's 11-GEV/C super high momentum spectrometer  

SciTech Connect (OSTI)

This paper describes the mechanical design and analysis of the cryostats for the two cos(2theta) quadrupoles and the cos(theta) dipole. All the magnets are currently being bid for commercial fabrication. The results of finite element analysis for the magnet cryostat helium vessels and outer vacuum chambers which investigate the mechanical integrity under maximum allowable internal working pressure, maximum allowable external working pressure, and cryogenic temperature are discussed. The allowable stress criterion is determined based on the allowable stress philosophy of the ASME codes. The computed cryogenic heat load of the magnets is compared with the allowable cryogenic consumption budget. The presented cool-down time of the magnets was studied under the conditions of a limited supply rate and a controlled temperature differential of 50 K in the magnets.

P. Brindza, E. Sun, S. Lassiter, M. Fowler

2010-04-01T23:59:59.000Z

267

Temperature dependence of the magnetic excitations in Gd  

SciTech Connect (OSTI)

Magnetic excitation spectra were measured for Gd in the and directions over the temperature range from 9 to 320/sup 0/K (T/sub c/ = 292.7/sup 0/K). Spin-wave-like modes are observed at T greater than or equal to T/sub c/. The critical wavevector for the appearance of these modes is proportional to the inverse correlation length.

Cable, J.W.; Nicklow, R.M.; Wakabayashi, N.

1985-08-01T23:59:59.000Z

268

Computation of the Field in an Axial Gap, Trapped-Flux Type Superconducting Electric Machine  

E-Print Network [OSTI]

Abstract—The Bulk Superconductivity Group at the University of Cambridge is currently investigating the use of high temper- ature superconductors in wire and bulk form to increase the electrical and magnetic loading of an axial gap, trapped flux... electric machines are an importantapplication of superconducting materials in both bulk and wire forms. Bulk high temperature superconductors, in partic- ular, are capable of trapping magnetic fields greater than 17 T below 30 K [1], [2], as well as up to 3...

Shen, Zejun; Ainslie, Mark D.; Campbell, Archie M.; Cardwell, David A.

2014-11-04T23:59:59.000Z

269

Superconductivity in iron compounds G. R. Stewart  

E-Print Network [OSTI]

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

Wu, Zhigang

270

Superconducting microfabricated ion traps  

E-Print Network [OSTI]

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

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

2010-12-14T23:59:59.000Z

271

SUPERCONDUCTING DEVICES  

E-Print Network [OSTI]

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

Clarke, John

2014-01-01T23:59:59.000Z

272

Competition between singlet and triplet superconductivity  

E-Print Network [OSTI]

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

Tian De Cao; Tie Bang Wang

2009-10-04T23:59:59.000Z

273

DESIGN OF A 10-T SUPERCONDUCTING DIPOLE MAGNET USING NIOBIUM-TIN CONDUCTOR  

E-Print Network [OSTI]

DIPOLE HAGNET USING NIOBIUM-TIN CONOOCTOR' C. Taylor, R.DIPOLE MAGNET USING NIOBIUM-TIN CONDUCTOR C. Taylor, R.slid tooling for the niobium- tin magnet .sre on halld, and

Taylor, C.

2011-01-01T23:59:59.000Z

274

Inductively-Charged High-Temperature Superconductors And Methods Of Use  

DOE Patents [OSTI]

The invention provides methods of charging superconducting materials and, in particular, methods of charging high-temperature superconducting materials. The methods generally involve cooling a superconducting material to a temperature below its critical temperature. Then, an external magnetic field is applied to charge the material at a nearly constant temperature. The external magnetic field first drives the superconducting material to a critical state and then penetrates into the material. When in the critical state, the superconducting material loses all the pinning ability and therefore is in the flux-flow regime. In some embodiments, a first magnetic field may be used to drive the superconducting material to the critical state and then a second magnetic field may be used to penetrate the superconducting material. When the external field or combination of external fields are removed, the magnetic field that has penetrated into the material remains trapped. The charged superconducting material may be used as solenoidal magnets, dipole magnets, or other higher order multipole magnets in many applications.

Bromberg, Leslie (Sharon, MA)

2003-09-16T23:59:59.000Z

275

First- and second-order transitions for a superconducting cylinder in a magnetic field obtained from a self-consistent solution of the Ginzburg-Landau equations  

SciTech Connect (OSTI)

Based on self-consistent solution of nonlinear GL equations, the phase boundary is found, which divides the regions of first- and second-order phase transitions to normal state of a superconducting cylinder of radius R, placed in magnetic field and remaining in the state of fixed vorticity m. This boundary is a complicated function of the parameters (m,R,{kappa}) ({kappa} is the GL parameter), which does not coincide with the simple phase boundary {kappa}=1/{radical}2, dividing the regions of first- and second-order phase transitions in infinite (open) superconducting systems.

Zharkov, G. F.

2001-06-01T23:59:59.000Z

276

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

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

277

Magnetic susceptibility of (Bi{sub 2-x}Sb{sub x})Te{sub 3} (0 < x < 1) alloys in the temperature range 2 to 50 K  

SciTech Connect (OSTI)

The superconducting quantum interferometer device with Josephson junctions (SQUID magnetometer) is used to study the temperature dependences of the magnetic susceptibility of (Bi{sub 2-x}Sb{sub x})Te{sub 3} (0 < x < 1) alloy crystals in the temperature range 2 to 50 K, at the magnetic field vector H orientations H perpendiular C{sub 3} and H Up-Tack C{sub 3} with respect to the crystal trigonal axis C{sub 3}. It is found that the magnetic susceptibility of the ion core of the samples under study is {chi}{sup G} = -0.35 Multiplication-Sign 10{sup -6} cm{sup 3}/g, the contribution of lattice defects to magnetic susceptibility can be disregarded, and the contribution of free carriers is of a diamagnetic nature in the entire studied temperature range. It is shown that the contribution of free carriers to the resulting magnetic susceptibility and its anisotropy can be described within the Pauli and Landau-Peierls approach. In calculating the magnetic susceptibility, taking into account the constant concentration of free carriers in the state of pronounced degeneracy, it is found that the temperature dependence of the anisotropic effective masses varies with crystal chemical composition. This is possibly associated with the complex structure of the valence band and its variation as the Sb{sub 2}Te{sub 3} content in the alloy increases.

Stepanov, N. P., E-mail: np-stepanov@mail.ru [Chernishevsky Zabaikalsky State Humanitarian Pedagogical University (Russian Federation); Nalivkin, V. U. [Chita State University (Russian Federation); Potapov, G. A. [Chernishevsky Zabaikalsky State Humanitarian Pedagogical University (Russian Federation)

2012-01-15T23:59:59.000Z

278

Low-temperature magnetization of (Ga,Mn) As semiconductors  

E-Print Network [OSTI]

of the Zeeman Hamil- tonian gS#3;BBS?z+gj#3;BBj?z, and from Eq. #1;1#2;: m ? mMF #14; mQF = ? #3;B j S + j #1;gS ? gj#2; . #1;5#2; When j=1/2 and gS=gj =2 the quantum fluctuation correc- tion to the magnetization vanishes even though the mean- field...Low-temperature magnetization of (Ga,Mn)As semiconductors T. Jungwirth,1,2 J. Ma?ek,3 K. Y. Wang,2 K. W. Edmonds,2 M. Sawicki,4 M. Polini,5 Jairo Sinova,6 A. H. MacDonald,7 R. P. Campion,2,8 L. X. Zhao,2,8 N. R. S. Farley,2,8 T. K. Johal,8 G. van...

Jungwirth, T.; Masek, J.; Wang, KY; Edmonds, KW; Sawicki, M.; Polini, M.; Sinova, Jairo; MacDonald, AH; Campion, RP; Zhao, LX; Farley, NRS; Johal, TK; van der Laan, G.; Foxon, CT; Gallagher, BL.

2006-01-01T23:59:59.000Z

279

High temperature superconductive materials and devices at microwave frequencies. (Latest citations from the INSPEC: Information Services for the Physics and Engineering Communities database). Published Search  

SciTech Connect (OSTI)

The bibliography contains citations concerning studies of microwave properties and characteristics of high temperature superconductive (HTSC) materials and devices. Citations discuss microwave absorption, surface resistance, surface impedance, energy loss, and characteristics of HTSC thin films. HTSC materials for the design and production of microwave resonators, filters, switches, and waveguides are decribed. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1992-12-01T23:59:59.000Z

280

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

E-Print Network [OSTI]

5.11: Zero ?eld electrical resistivity vs temperature ?(T )technique. The electrical resistivity ? vs temperature T5.3: The zero-?eld electrical resistivity ? vs temperature T

Sayles, Todd Allen

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Model for local para-Cooperons possibly relevant for high-temperature superconductors  

SciTech Connect (OSTI)

We examine the superconductivity analog of the local paramagnon concept in itinerant magnetism. This local-pairing model involves critical temperatures which are /ital not/ exponential, in contrast with the usual BCS ones. Interesting consequences are expected, in particular concerning the possibility of reaching high superconducting temperatures.

Beal-Monod, M. T.

1989-06-01T23:59:59.000Z

282

Final Report: MATERIALS, STRANDS, AND CABLES FOR SUPERCONDUCTING ACCELERATOR MAGNETS [Grant Number DE-SC0010312  

SciTech Connect (OSTI)

Our program consisted of the two components: Strand Research and Cable Research, with a focus on Nb3Sn, Bi2212, and YBCO for accelerator magnet applications. We demonstrated a method to refine the grains in Nb3Sn by a factor of two, reaching 45 nm grain sizes, and layer Jcs of 6 kA/mm2 at 12 T. W also measured conductor magnetization for field quality. This has been done both with Nb3Sn conductor, as well as Bi:2212 strand. Work in support of quench studies of YBCO coils was also performed. Cable loss studies in Nb3Sn focused on connecting and comparing persistent magnetization and coupling magnetization for considering their relative impact on HEP machines. In the area of HTS cables, we have investigated both the quench in multistrand YBCO CORC cables, as well as the magnetization of these cables for use in high field magnets. In addition, we examined the magnetic and thermal properties of large (50 T) solenoids.

Sumption, Mike; Collings, E.

2014-10-29T23:59:59.000Z

283

Kamacite blocking temperatures and applications to lunar magnetism Ian Garrick-Bethell a,  

E-Print Network [OSTI]

Kamacite blocking temperatures and applications to lunar magnetism Ian Garrick-Bethell a magnetism iron paleomagnetism The long-term stability of remanent magnetization is a requirement for paleomagnetic studies. Here we present calculations that predict the magnetic relaxation times of single domain

Weiss, Benjamin P.

284

Primary Beam Steering Due to Field Leakage from Superconducting SHMS Magnets  

E-Print Network [OSTI]

Simulations of the magnetic fields from the Super High Momentum Spectrometer in Hall C at Thomas Jefferson National Accelerator Facility show significant field leakage into the region of the primary beam line between the target and the beam dump. Without mitigation, these remnant fields will steer the unscattered beam enough to limit beam operations at small scattering angles. Presented here are magnetic field simulations of the spectrometer magnets and a solution using optimal placement of a minimal amount of shielding iron around the beam line.

Michael H. Moore; Buddhini P. Waidyawansa; Silviu Covrig; Roger Carlini; Jay Benesch

2014-08-26T23:59:59.000Z

285

Primary beam steering due to field leakage from superconducting SHMS magnets  

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

Simulations of the magnetic fields from the Super High Momentum Spectrometer in Hall C at Thomas Jefferson National Accelerator Facility show significant field leakage into the region of the primary beam line between the target and the beam dump. Without mitigation, these remnant fields will steer the unscattered beam enough to limit beam operations at small scattering angles. Presented here are magnetic field simulations of the spectrometer magnets and a solution using optimal placement of a minimal amount of shielding iron around the beam line.

Moore, M.H.; Waidyawansa, B.P.; Covrig, S.; Carlini, R.; Benesch, J.

2014-11-01T23:59:59.000Z

286

Mixed-mu superconducting bearings  

DOE Patents [OSTI]

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

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

1998-01-01T23:59:59.000Z

287

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

288

Development of an alternating integrator for magnetic measurements for experimental advanced superconducting tokamak  

SciTech Connect (OSTI)

A high-performance integrator is one of the key electronic devices for reliably controlling plasma in the experimental advanced superconducting tokamak for long pulse operation. We once designed an integrator system of real-time drift compensation, which has a low integration drift. However, it is not feasible for really continuous operations due to capacitive leakage error and nonlinearity error. To solve the above-mentioned problems, this paper presents a new alternating integrator. In the new integrator, the integrator system of real-time drift compensation is adopted as one integral cell while two such integral cells work alternately. To achieve the alternate function, a Field Programmable Gate Array built in the digitizer is utilized. The performance test shows that the developed integrator with the integration time constant of 20 ms has a low integration drift (<15 mV) for 1000?s.

Liu, D. M., E-mail: dmliu@live.cn; Zhao, W. Z.; He, Y. G.; Chen, B. [School of Electrical Engineering and Automation, Hefei University of Technology, Hefei 230009 (China); Wan, B. N.; Shen, B.; Huang, J.; Liu, H. Q. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

2014-11-15T23:59:59.000Z

289

Low-temperature magnetic characterization of optimum and etch-damaged in-plane magnetic tunnel junctions  

SciTech Connect (OSTI)

We describe low-temperature characterization of magnetic tunnel junctions (MTJs) patterned by reactive ion etching for spin-transfer-torque magnetic random access memory. Magnetotransport measurements of typical MTJs show increasing tunneling magnetoresistance (TMR) and larger coercive fields as temperature is decreased down to 10 K. However, MTJs selected from the high-resistance population of an MTJ array exhibit stable intermediate magnetic states when measured at low temperature and show TMR roll-off below 100 K. These non-ideal low-temperature behaviors arise from edge damage during the etch process and can have negative impacts on thermal stability of the MTJs.

Kan, Jimmy J.; Gottwald, Matthias; Fullerton, Eric E. [Center for Magnetic Recording Research, University of California, San Diego, La Jolla, California 92093 (United States)] [Center for Magnetic Recording Research, University of California, San Diego, La Jolla, California 92093 (United States); Lee, Kangho; Kang, Seung H. [Advanced Technology, Qualcomm, Inc., San Diego, California 92121 (United States)] [Advanced Technology, Qualcomm, Inc., San Diego, California 92121 (United States)

2013-09-21T23:59:59.000Z

290

Experimental evaluation of vertically versus horizontally split yokes for SSC (Superconducting Super Collider) dipole magnets  

SciTech Connect (OSTI)

The yoke in SSC dipole magnets provides mechanical support to the collared coil as well as serving as a magnetic element. The yoke and skin are used to increase the coil prestress and reduce collar deflections under excitation. Yokes split on the vertical or horizontal mid-plane offer different advantages in meeting these objectives. To evaluate the relative merits of the two configuration a 1.8 m model dipole was assembled and tested first with horizontally split and then with vertically split yoke laminations. The magnet was extensively instrumented to measure azimuthal and axial stresses in the coil and the cold mass skin resulting from cooldown and excitation. Mechanical behavior of this magnet with each configuration is compared with that of other long and short models and with calculations. 13 refs., 5 figs.

Strait, J.; Coulter, K.; Jaffery, T.; Kerby, J.; Koska, W.; Lamm, M.J.

1990-05-03T23:59:59.000Z

291

Magnetic field dependence of the proximity induced triplet superconductivity at ferromagnet/superconductor interfaces  

E-Print Network [OSTI]

Long-ranged superconductor proximity effects recently found in superconductor-ferromagnetic (S-F) systems are generally attributed to the formation of triplet-pairing correlations due to various forms of magnetic inhomogeneities at the S-F interface...

Kalcheim, Yoav; Felner, Israel; Millo, Oded; Kirzhner, Tal; Koren, Gad; Di Bernardo, Angelo; Egilmez, Mehmet; Blamire, Mark G.; Robinson, Jason W. A.

2014-05-21T23:59:59.000Z

292

The Magnificent Seven: Magnetic fields and surface temperature distributions  

E-Print Network [OSTI]

Presently seven nearby radio-quiet isolated neutron stars discovered in ROSAT data and characterized by thermal X-ray spectra are known. They exhibit very similar properties and despite intensive searches their number remained constant since 2001 which led to their name ``The Magnificent Seven''. Five of the stars exhibit pulsations in their X-ray flux with periods in the range of 3.4 s to 11.4 s. XMM-Newton observations revealed broad absorption lines in the X-ray spectra which are interpreted as cyclotron resonance absorption lines by protons or heavy ions and / or atomic transitions shifted to X-ray energies by strong magnetic fields of the order of 10^13 G. New XMM-Newton observations indicate more complex X-ray spectra with multiple absorption lines. Pulse-phase spectroscopy of the best studied pulsars RX J0720.4-3125 and RBS 1223 reveals variations in derived emission temperature and absorption line depth with pulse phase. Moreover, RX J0720.4-3125 shows long-term spectral changes which are interpreted as due to free precession of the neutron star. Modeling of the pulse profiles of RX J0720.4-3125 and RBS 1223 provides information about the surface temperature distribution of the neutron stars indicating hot polar caps which have different temperatures, different sizes and are probably not located in antipodal positions.

F. Haberl

2006-09-04T23:59:59.000Z

293

Magnetization curves for thin films of layered type-II superconductors, Kolmogorov-Arnold-Moser theory, and the devil's staircase  

SciTech Connect (OSTI)

Magnetization curves for a thin-layered superconducting film in parallel magnetic field have been shown to become devil's staircases provided the superconducting layers are perpendicular to the film plane. The transition from an incomplete to a complete devil's staircase with decreasing temperature is predicted. A chain of vortices is described by the generalized Frenkel-Kontorova model.

Burkov, S.E. (Laboratory of Atomic and Solid State Physics, Clark Hall, Cornell University, Ithaca, New York (USA) Landau Institute for Theoretical Physics, Moscow (U.S.S.R))

1991-08-01T23:59:59.000Z

294

Weak magnetic field effects on chiral critical temperature in a nonlocal Nambu--Jona-Lasinio model  

E-Print Network [OSTI]

In this article we study the nonlocal Nambu--Jona-Lasinio model with a Gaussian regulator in the chiral limit. Finite temperature effects and the presence of a homogeneous magnetic field are considered. The magnetic evolution of the critical temperature for chiral symmetry restoration is then obtained. Here we restrict ourselves to the case of low magnetic field values, being this a complementary discussion to the exisiting analysis in nonlocal models in the strong magnetic field regime.

M. Loewe; F. Marquez; C. Villavicencio; R. Zamora

2014-10-27T23:59:59.000Z

295

Color-Superconducting Gap in the Presence of a Magnetic Field  

E-Print Network [OSTI]

We explore the effects of an external magnetic field in the structure and magnitude of the diquark condensate in a three massless quark flavor color superconductor. It is shown that the long-range component $\\widetilde{B}$ of the external magnetic field that penetrates the color-flavor locked (CFL) phase modifies its gap structure, producing a new phase of lower symmetry. Our analysis is performed within an NJL effective field theory with four-fermion interactions, inspired by one-gluon exchange. Using Ritus' method, we compute the quark propagators in the presence of a background magnetic field, and derive the gap equations for arbitrary values of the field. An analytical solution is found for strong magnetic fields. A main outcome of our study is that the $\\widetilde{B}$ field tends to strengthen the gaps that get contributions from pairs of $\\widetilde{Q}$-charged quarks. These gaps are enhanced through the field-dependent density of states of the $\\widetilde{Q}$-charged quarks on the Fermi surface. Our considerations are relevant for the study of highly magnetized compact stars.

Efrain J. Ferrer; Vivian de la Incera; Cristina Manuel

2006-05-17T23:59:59.000Z

296

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

297

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

298

Superconducting radiofrequency window assembly  

DOE Patents [OSTI]

The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly has a superconducting metal-ceramic design. The srf window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.

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

1997-03-11T23:59:59.000Z

299

Superconductive radiofrequency window assembly  

DOE Patents [OSTI]

The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The SRF window assembly has a superconducting metal-ceramic design. The SRF window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the SRF window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.

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

1998-05-19T23:59:59.000Z

300

Studies of time dependence of fields in TEVATRON superconducting dipole magnets  

SciTech Connect (OSTI)

The time variation in the magnetic field of a model Tevatron dipole magnet at constant excitation current has been studied. Variations in symmetry allowed harmonic components over long time ranges show a log t behavior indicative of ''flux creep.'' Both short time range and long time range behavior depend in a detailed way on the excitation history. Similar effects are seen in the remnant fields present in full-scale Tevatron dipoles following current ramping. Both magnitudes and time dependences are observed to depend on details for the ramps, such as ramp rate, flattop duration, and number of ramps. In a few magnets, variations are also seen in symmetry unallowed harmonics. 9 refs., 10 figs.

Hanft, R.W.; Brown, B.C.; Herrup, D.A.; Lamm, M.J.; McInturff, A.D.; Syphers, M.J.

1988-08-22T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Superconductivity and Physical Properties of CaPd2Ge2 Single Crystals  

SciTech Connect (OSTI)

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

302

Evolution of magnetic and superconducting fluctuations with doping of high-T{sub c} superconductors : an electronic Raman scattering study.  

SciTech Connect (OSTI)

For YBa{sub 2}Cu{sub 3}O{sub 6+{delta}} and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 3{+-}{delta}} superconductors, electronic Raman scattering from high- and low-energy excitations has been studied in relation to the hole doping level, temperature, and energy of the incident photons. For underdoped superconductors, it is concluded that short range antiferromagnetic (AF) correlations persist with hole doping and doped single holes are incoherent in the AF environment. Above the superconducting (SC) transition temperature T{sub c} the system exhibits a sharp Raman resonance of B{sub 1g} symmetry and about 75 meV energy and a pseudogap for electron-hole excitations below 75 meV, a manifestation of a partially coherent state forming from doped incoherent quasi-particles. The occupancy of the coherent state increases with cooling until phase ordering at T{sub c} produces a global SC state.

Blumberg, G.

1998-01-14T23:59:59.000Z

303

Superconductivity, Superfluidity and Holography  

E-Print Network [OSTI]

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

Alberto Salvio

2013-01-16T23:59:59.000Z

304

Superconducting Transition-Temperature and Other Properties of Thin Metallic-Films  

E-Print Network [OSTI]

-coupling supercondUctors, the transi- tion. temperature 7, of a thin film is larger than the bulk T, . A calculation by Kirzhnits and Maksi- mov suggested that surface phonons may be re- sponsible for this enhancement. An experiment involving deposition of noble...

Allen, Roland E.

1975-01-01T23:59:59.000Z

305

Proposal for the Award of Two Contracts for the Supply of High Temperature SuperconductingTape for the LHC  

E-Print Network [OSTI]

This document concerns the award of two contracts for the supply of high temperature superconducting (HTS) BSCCO 2223 Ag-Au tape, of two different types, for the LHC. Following a call for tenders (IT-3143/AT/LHC) sent on 5 March 2003 to four firms in two Member States and one firm in the US, CERN received one tender from a firm in a Member State and one tender from the firm in the United States. The Finance Committee is invited to agree to the negotiation of contracts with: - VACUUMSCHMELZE (DE), for the supply of 17 km of HTS BSCCO 2223 Ag-Au tape with Ic > 66 A at 77 K for a total amount of 807 833 euros (1 201 900 Swiss francs), not subject to revision, with an option for the supply of up to additional 17 km of HTS BSCCO 2223 Ag-Au tape, for a total amount of up to 807 833 euros (1 201 900 Swiss francs), not subject to revision, bringing the total amount to a maximum of 1 615 666 euros (2 403 800 Swiss francs), not subject to revision. The rate of exchange used is that stipulated in the tender.

2003-01-01T23:59:59.000Z

306

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

307

SUPERCONDUCTING DEVICES  

E-Print Network [OSTI]

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

Clarke, John

2014-01-01T23:59:59.000Z

308

MICROSTRUCTURE OF SUPERCONDUCTING MGB(2).  

SciTech Connect (OSTI)

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

309

Performing temperature feedback controlled tissue photo-coagulation using magnetic resonance thermometry  

E-Print Network [OSTI]

controlled photo-coagulation using magnetic resonance imaging as the non-invasive means of temperature feedback. The desired coagulation depth was controlled at a constant temperature of 40 degrees for different amounts of time and the actual coagulation...

Sampath, Smita

1999-01-01T23:59:59.000Z

310

Temperature Difference Leads to Magnetism | Physical Review Focus Previous Story / Volume 28 archive  

E-Print Network [OSTI]

Temperature Difference Leads to Magnetism | Physical Review Focus Previous Story / Volume 28 Leads to Magnetism J. Wu/Univ. of California, Berkeley Heat field. Heating the right edge of an n a magnetic field pointing out of the screen, according to computer simulations. Computer simulations suggest

Wu, Junqiao

311

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

312

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers  

DOE Patents [OSTI]

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced. 7 figures.

Fan, N.Q.; Clarke, J.

1993-10-19T23:59:59.000Z

313

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers  

DOE Patents [OSTI]

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced.

Fan, Non Q. (San Diego, CA); Clarke, John (Berkeley, CA)

1993-01-01T23:59:59.000Z

314

Anisotropic magnetoresistance of single-crystal HoNi2B2C and the interplay of magnetic and superconducting order  

E-Print Network [OSTI]

The in-plane resistivity and magnetization measurements as a function of the magnitude and direction of the magnetic field and the temperature are reported for single-crystal samples of the HoNi2B2C magnetic superconductor. Features corresponding...

Rathnayaka, KDD; Naugle, Donald G.; Cho, BK; Canfield, PC.

1996-01-01T23:59:59.000Z

315

Superconducting Materials and Conductors : Fabrication and Limiting Parameters  

E-Print Network [OSTI]

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

Bottura, L

2013-01-01T23:59:59.000Z

316

Abstract--Temperature, current density and magnetic field distributions in YBCO bulk superconductor during a pulsed-field  

E-Print Network [OSTI]

-- bulk YBaCuO, stored magnetic energy, thermal coupling, magnetization, modelling. I. INTRODUCTION HE as cryo-permanent magnets [1], [2]. To magnetize the HTS, pulsed field magnetization (PFM) process1 Abstract-- Temperature, current density and magnetic field distributions in YBCO bulk

Paris-Sud XI, Université de

317

Low temperature and magnetic field behaviour of the (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy  

SciTech Connect (OSTI)

Measurements of the temperature (T) dependence of the magnetic susceptibility (?) and electrical resistance (R) on an antiferromagnetic (AFM) (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy are reported in order to probe the existence of quantum critical behaviour (QCB) utilizing static magnetic fields (H) as a tuning parameter. The results indicate that an increase in H suppresses T{sub N} in such a way that it varies exponentially with increasing H. R(T) measurements show evidence of possible superconducting (SC) behaviour below 1?K at H?=?0?T. These results therefore indicate the coexistence of the AFM and SC phases in the (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy.

Jacobs, B. S., E-mail: sjacobs@uj.ac.za; Sheppard, C. J.; Prinsloo, A. R. E. [Department of Physics, University of Johannesburg, P.O. Box 524, Auckland Park 2006 (South Africa); Lodya, L. [Sasol Technology, Research and Development, 1 Klasie Havenga Road, Sasolburg 1947 (South Africa)

2014-05-07T23:59:59.000Z

318

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

319

Bifurcation to vortex solutions in superconducting lms  

E-Print Network [OSTI]

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

Chapman, Jon

320

Thermal conduction of SSC (Superconducting Super Collider) wire  

SciTech Connect (OSTI)

A method suitable for measuring the thermal conductivity of good thermal conductors at low temperatures was implemented. It successfully served its purpose: to detect the effect of doping with manganese the interfilament part of the copper matrix of the superconducting wire used in the magnets of the Superconducting Super Collider. It uses two heaters and one thermometer per sample reducing the accuracy requirement on the thermometers, automatically compensating for zero offsets and reducing the number of critical thermal contacts. Commercially available strain gauges are used as heaters. 3 refs., 2 figs.

Kuchnir, M.; Tague, J.L.

1989-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Regeneration tests of a room temperature magnetic refrigerator and heat pump  

E-Print Network [OSTI]

A magnetic heat pump apparatus consisting of a solid magnetic refrigerant, gadolinium, and a liquid regenerator column of ethanol and water has been tested. Utilizing a 7T field, it produced a maximum temperature span of 80 K, and in separate tests, a lowest temperature of 241 K and a highest temperature of 328 K. Thermocouples, placed at intervals along the regenerator tube, permitted measurement of the temperature distribution in the regenerator fluid. No attempt was made to extract refrigeration from the device, but analysis of the temperature distributions shows that 34 watts of refrigeration was produced.

Brown, G V

2014-01-01T23:59:59.000Z

322

Near fifty percent sodium substituted lanthanum manganites—A potential magnetic refrigerant for room temperature applications  

SciTech Connect (OSTI)

Nearly half of lanthanum sites in lanthanum manganites were substituted with monovalent ion-sodium and the compound possessed distorted orthorhombic structure. Ferromagnetic ordering at 300?K and the magnetic isotherms at different temperature ranges were analyzed for estimating magnetic entropy variation. Magnetic entropy change of 1.5?J·kg{sup ?1}·K{sup ?1} was observed near 300?K. An appreciable magnetocaloric effect was also observed for a wide range of temperatures near 300?K for small magnetic field variation. Heat capacity was measured for temperatures lower than 300?K and the adiabatic temperature change increases with increase in temperature with a maximum of 0.62?K at 280?K.

Sethulakshmi, N.; Anantharaman, M. R., E-mail: mraiyer@yahoo.com [Department of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala (India); Al-Omari, I. A. [Department of Physics, Sultan Qaboos University, PC 123 Muscat, Sultanate of Oman (Oman); Suresh, K. G. [Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India)

2014-03-03T23:59:59.000Z

323

Introduction to Color Superconductivity  

E-Print Network [OSTI]

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

G. Nardulli

2006-10-23T23:59:59.000Z

324

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

325

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

326

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

327

Thermal and electrical stabilities of solid nitrogen (SN2) cooled YBCO coated conductors for HTS magnet applications  

E-Print Network [OSTI]

Recently, a cooling system using a solid cryogen such as solid nitrogen (SN2), was introduced for high temperature superconducting (HTS) magnet applications. In order to apply the SN2 cooling system successfully to HTS ...

Song, J. B.

328

Unifying the strain and temperature scaling laws for the pinning force density in superconducting niobium-tin multifilamentary wires  

E-Print Network [OSTI]

niobium-tin multifilamentary wires Najib Cheggoura) and Damian P. Hampshire Superconductivity Group critical current density (Jc) tolerance to strain , performed on a bronze processed niobium-tin . 2 The power m was found to be about 1 for niobium-tin (Nb3Sn) although the power n in the Fietz

Hampshire, Damian

329

Structural and magnetic properties and superconductivity in Ba(Fe{sub 1-x}TM{sub x}){sub 2}As{sub 2}  

SciTech Connect (OSTI)

We studied the effects on structural and magnetic phase transitions and the emergence of superconductivity in transition metal substituted BaFe{sub 2}As{sub 2}. We grew four series of Ba(Fe{sub 1-x}TM{sub x}){sub 2}As{sub 2} (TM=Ru, Mn, Co+Cr and Co+Mn) and characterized them by crystallographic, magnetic and transport measurements. We also subjected Ba(Fe{sub 1-x}Cr{sub x}){sub 2}As{sub 2} and Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} to heat treatment to explore what changes might be induced.

Thaler, Alexander

2012-07-23T23:59:59.000Z

330

The positive ion temperature effect in magnetized electronegative plasma sheath with two species of positive ions  

SciTech Connect (OSTI)

The properties of a magnetized multi-component (two species of positive ions, negative ions and electrons) plasma sheath with finite positive ion temperature are studied. By using three fluid hydrodynamic model and some dimensionless variables, the ion (both lighter and heavier positive ions, and negative ions) densities, the ion (only for positive ions) velocities, and electric potential inside the sheath are investigated. In addition, the absence and presence of magnetic field and the orientation of magnetic field are considered. It is noticed that, with increase of positive ion temperature, the lighter positive ion density peaks increase only at the sheath edge and shift towards the sheath edge for both absence and presence of magnetic field. For heavier positive ions, in the absence of magnetic field, the density peaks increase at the sheath edge. But in the presence of magnetic field, the density fluctuations increase at the sheath edge. For both the cases, the density peaks shift towards the sheath edge.

Shaw, A. K. [Centre of Plasma Physics, Institute for Plasma Research, Sonapur-782 402, Guwahati, Assam (India); Institute for Plasma Research, Bhat, Gandhinagar-382 428, Gujarat (India); Kar, S. [Institute for Plasma Research, Bhat, Gandhinagar-382 428, Gujarat (India); Goswami, K. S. [Centre of Plasma Physics, Institute for Plasma Research, Sonapur-782 402, Guwahati, Assam (India)

2012-10-15T23:59:59.000Z

331

Physica E 40 (2007) 1224 Electron coherence at low temperatures: The role of magnetic impurities  

E-Print Network [OSTI]

of the ground state of an electron gas at zero temperature is one of the major challenges in condensed matter the saturation of tf in these samples, cognizant of the role of magnetic scattering. For the cleanest samples

332

Spontaneous Emission Near Superconducting Bodies  

E-Print Network [OSTI]

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

Bo-Sture K. Skagerstam; Per Kristian Rekdal

2007-06-07T23:59:59.000Z

333

Optimization of operating temperature in cryocooled HTS magnets for compactness and efficiency  

E-Print Network [OSTI]

superconductor (HTS) magnets is presented, aiming simultaneously at small size and low energy consumption. The magnet systems considered here are refrigerated by a closed-cycle cryocooler, and liquid cryogens may. The excessive energy consumption or the degraded overall efficiency caused by a low temperature operation could

Chang, Ho-Myung

334

Superconducting materials for large scale applications  

SciTech Connect (OSTI)

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

335

Potential impact of high temperature superconductors on maglev transportation  

SciTech Connect (OSTI)

This report describes the potential impact that high-temperature superconductors (HTSs) may have on transportation by magnetically levitated vehicles. It is not intended as a planning document, but rather as an overview of potential HTS applications to magnetic-levitation (maglev) transportation. The present maglev program in the United States is summarized, and the present status of development of HTSs is described. Areas identified for possible impact on maglev technology are (1) liquid-nitrogen-cooled levitation magnets, (2) magnetic-field shielding of the passenger compartment, (3) superconducting magnetic energy storage for wayside power, (4) superconducting bearings for flywheel energy storage for wayside power, (5) downleads to continuously powered liquid-helium-cooled levitation magnets, and (6) liquid-hydrogen-cooled levitation magnets and linear motor propulsion windings. Major technical issues that remain to be resolved for the use of HTSs in maglev applications include thermal magnetic stability, mechanical properties, and critical current density at liquid-nitrogen temperatures.

Hull, J.R.

1992-02-01T23:59:59.000Z

336

Compact magnetic energy storage module  

DOE Patents [OSTI]

A superconducting compact magnetic energy storage module in which a plurality of superconducting toroids, each having a toroidally wound superconducting winding inside a poloidally wound superconducting winding, are stacked so that the flow of electricity in each toroidally wound superconducting winding is in a direction opposite from the direction of electrical flow in other contiguous superconducting toroids. This allows for minimal magnetic pollution outside of the module.

Prueitt, Melvin L. (Los Alamos, NM)

1994-01-01T23:59:59.000Z

337

Compact magnetic energy storage module  

DOE Patents [OSTI]

A superconducting compact magnetic energy storage module in which a plurality of superconducting toroids, each having a toroidally wound superconducting winding inside a poloidally wound superconducting winding, are stacked so that the flow of electricity in each toroidally wound superconducting winding is in a direction opposite from the direction of electrical flow in other contiguous superconducting toroids. This allows for minimal magnetic pollution outside of the module. 4 figures.

Prueitt, M.L.

1994-12-20T23:59:59.000Z

338

Evaluation of permanent magnets for high temperature operations  

E-Print Network [OSTI]

250 276 300 25 60 0 Temperature ( C) Fig. B. Tractive Force per unit Volume of Ni Cylinder vs. Temperature for barium ferrite. 'I. 2 1. 'I 'I. O O. e 0. 6 0. 7 Unannaallad ~ m g 0. 4 0. 6 OA 0. 3 0. 2 0. 1 0. 0 Cooling A noalls 24... 425 4% 0 75 '100125150175200225250275 0 Temperature ( C) 0 20 a 30 + 10 x 40 v SO Fig. lla. Tractive Force per unit Volume of Ni Cylinder vs. Temperature for Alnico 8, annealled from 0 to 50 hours in 10 hour steps. M E u m m 0 &i 'o 0 8 u...

Van Hees, Elizabeth

2012-06-07T23:59:59.000Z

339

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

to MW/40 MWI-IR Battery Energy Storage Facility", proc. 23rdcompressed air, and battery energy storage are all only 65

Hassenzahl, W.

2011-01-01T23:59:59.000Z

340

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

describes the general technology of SMES, and explains theIn each of these technologies, except SMES, the electricalva lue of SMES compared to other technologies l5 . The

Hassenzahl, W.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

angle for the SCR firing circuit. This in turn controls theare controlled by a firing circuit. (We describe here theVoltage pulses from the firing circuits cause the SCRs to

Hassenzahl, W.

2011-01-01T23:59:59.000Z

342

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

Encrgy Storage Plant" , EPRI Report EM-3457, April 1984. [4521st century. REFERENCES The EPRI Regional Systems preparedby J. J. Mulvaney, EPRI Report EPRI P-19S0SR, (1981). [2J O.

Hassenzahl, W.

2011-01-01T23:59:59.000Z

343

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

hydro, compressed air, and battery energy storage are allenergy storage sys tem s suc h as pumped hydro and compressed air.

Hassenzahl, W.

2011-01-01T23:59:59.000Z

344

Research Interests: Application of nanotechnology to create novel permanent magnets (spring magnets)  

E-Print Network [OSTI]

; Superconductivity; Synchrotron-Radiation Instrumentation; Magnetism; (Neutron Scattering; Lattice Dynamics; Low

Kemner, Ken

345

Temperature measurement of axisymmetric flames under the influence of magnetic field using Talbot interferometry  

SciTech Connect (OSTI)

Combustion process control is related with ecological improvement and the problem of energy efficiency; hence it has a wide interest at both economical and scientific levels. Application of a magnetic field is one of the most promising methods of combustion control. The presence of magnetic field induces the changes in flame behavior. The effect of uniform magnetic field developed by permanent magnet is studied by Talbot interferometry using circular gratings. Experimental results show a small decrease in flame temperature and increase in flame dimensions.

Agarwal, Shilpi, E-mail: sipi.agarwal@gmail.com, E-mail: manojklakra@gmail.com, E-mail: cshakher@iddc.iitd.ac.in; Kumar, Manoj, E-mail: sipi.agarwal@gmail.com, E-mail: manojklakra@gmail.com, E-mail: cshakher@iddc.iitd.ac.in; Shakher, Chandra, E-mail: sipi.agarwal@gmail.com, E-mail: manojklakra@gmail.com, E-mail: cshakher@iddc.iitd.ac.in [Instrument Design Development Centre, Indian Institute of Technology Delhi, HauzKhas, New Delhi - 110016 (India)

2014-10-15T23:59:59.000Z

346

Reinforced fluropolymer nanocomposites with high-temperature superconducting Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y}  

SciTech Connect (OSTI)

Bismuth Strontium Calcium Copper Oxide (Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y})/Polyvinylidene fluoride (PVDF) nanocomposite was prepared and their thermal properties were analyzed. The composite consists of the polyvinylidene fluoride (PVDF) as an insulating polymer matrix, and homogenously distributed Bismuth strontium calcium copperoxide (2212) nanoparticles. SEM data shows flaky grains of the superconductor coated and linked by polymer. Differential scanning calorimetry (DSC) results indicated that the melting point was not affected significantly by the addition of BSCCO. However, the addition of superconducting ceramic resulted in an extra melting peak at a lower temperature (145°C). Thermogravimetric analysis of the samples shows that the onset decomposition temperature of the PVDF matrix was decreased by the addition of SC filler.

Jayasree, T. K., E-mail: drjayasreetk@gmail.com [Laboratory for Molecular Photonics and Electronic (Lamp), Department of Physics, National Institute of Technology, Calicut, Kerala, India - 673601 and Department of Physics, Sree Ayyappa College, Eramallikkara, Chengannur, Kerala-689109 (India)

2014-10-15T23:59:59.000Z

347

Thin superconducting films: sputtering, characterizations, and applications. January 1975-December 1987 (citations from the INSPEC: Information Services for the Physics and Engineering Communities data base). Report for January 1975-December 1987  

SciTech Connect (OSTI)

This bibliography contains citations concerning the theories, production, characterizations, and applications of thin superconducting films. Sputtering techniques for fabricating thin superconducting films from transition metals, rare earth compounds, aluminum group metals, and germanium group metals are discussed. Their electrical, magnetic, and thermal properties are also examined. Topics include critical characteristics, transition temperatures, superconductive tunnelling and junctions, electrical impedances and energy gaps, persistent currents, and size effects. Thin superconducting film applications include optical detection, optical switching, Josephson junctions, microwave devices, and surface acoustic devices. (Contains 302 citations fully indexed and including a title list.)

Not Available

1988-01-01T23:59:59.000Z

348

High temperature magnetic properties of SmCo5/-Fe(Co) bulk nanocomposite magnets  

E-Print Network [OSTI]

-compaction route. Up to 30% of the Fe soft magnetic phase has been added to the composites with grain size (!150 C) are needed for applica- tions in advanced power systems, including electric vehicles and wind mill turbines.1,2 Nd2Fe14B-based magnets are the material of choice in systems where weight or size

Liu, J. Ping

349

A superconducting-nanowire 3-terminal electronic device  

E-Print Network [OSTI]

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

Adam N. McCaughan; Karl K. Berggren

2014-03-25T23:59:59.000Z

350

Reduced electron temperature in a magnetized inductively-coupled plasma with internal coil  

SciTech Connect (OSTI)

The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanent magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.

Arancibia Monreal, J.; Chabert, P. [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France)] [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France); Godyak, V. [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States) [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States); Michigan Institute for Plasma Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2013-10-15T23:59:59.000Z

351

Spontaneous Fluctuations of a Temperature Filament in a Magnetized Plasma  

E-Print Network [OSTI]

, and G. J. Morales Department of Physics and Astronomy, University of California, Los Angeles, California because temperature laments can arise in a wide class of plasma environments, e.g., solar corona 3G generated in the Large Plasma Device LAPD at the University of California, Los Angeles. For the purposes

California at Los Angles, University of

352

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

353

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

354

Application of simultaneous active and reactive power modulation of superconducting magnetic energy storage unit to damp turbine-generator subsynchronous oscillations  

SciTech Connect (OSTI)

An active and reactive power (P-Q) simultaneous control scheme which is based on a superconducting magnetic energy storage (SMES) unit is designed to damp out the subsynchronous resonant (SSR) oscillations of a turbine-generator unit. In order to suppress unstable torsional mode oscillations, a proportional-integral-derivative (PID) controller is employed to modulate the active and reactive power input/output of the SMES unit according to speed deviation of the generator shaft. The gains of the proposed PID controller are determined by pole assignment approach based on modal control theory. Eigenvalue analysis of the studied system shows that the PID controller is quite effective over a wide range of operating conditions. Dynamic simulations using the nonlinear system model are also performed to demonstrate the damping effect of the proposed control scheme under disturbance conditions.

Wu, Chijui; Lee, Yuangshung (National Taiwan Inst. of Tech., Taipie (Taiwan, Province of China))

1993-03-01T23:59:59.000Z

355

Superconducting radiofrequency window assembly  

DOE Patents [OSTI]

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

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

1997-01-01T23:59:59.000Z

356

Superconductive radiofrequency window assembly  

DOE Patents [OSTI]

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

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

1998-01-01T23:59:59.000Z

357

Universal superconducting and magnetic properties of the (CaxLa12x)(Ba1.752xLa0.25x)Cu3Oy system: a mSR investigation  

E-Print Network [OSTI]

Universal superconducting and magnetic properties of the (CaxLa12x)(Ba1.752xLa0.25þx)Cu3Oy system 2002; accepted 30 September 2002 by Y.J. Uemura Abstract The (CaxLa12x)(Ba1.752xLa0.25þx) Cu3Oy system or detrimental to superconductivity? We address these questions by investigating the (Cax La12x)(Ba1.752xLa0.25þx

Keren, Amit

358

Low temperature magnetic properties of magnesium substituted YbMnO{sub 3}  

SciTech Connect (OSTI)

Structural and magnetic properties of polycrystalline Yb{sub 1?x}Mg{sub x}MnO{sub 3} (x = 0, 0.05 and 0.10) hexagonal compounds prepared by solid state method, have been studied. The structural analyses of the samples were carried out by Rietveld analysis of neutron diffraction data. With increasing Mg content, we find that the lattice parameter a decreases and c increases whereas the overall Mn-O bond length decreases. Magnetization measured as a function of magnetic field at 2.5 K exhibits hysteresis, which is attributed to ferromagnetic like ordering of Yb{sup 3+} sublattice. Temperature dependence of ac magnetic susceptibility, ?{sub ac}(T), shows no signature of spin-glass behavior. ?”(T) exhibits a sudden increase at low temperatures which is due to ordering of Yb{sup 3+} sublattice.

Sattibabu, Bhumireddi, E-mail: bsb.satti@gmail.com; Bhatnagar, Anil K., E-mail: bsb.satti@gmail.com; Mohan, Dasari, E-mail: bsb.satti@gmail.com; Das, Dibakar, E-mail: bsb.satti@gmail.com; Sundararaman, Mahadevan, E-mail: bsb.satti@gmail.com [School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad-500046 (India); Siruguri, Vasudeva; Rayaprol, Sudhindra [UGC-DAE Consortium for Scientific Research, Mumbai Centre, R-5 Shed, Bhabha Atomic Research Centre, Mumbai-400085 (India)

2014-04-24T23:59:59.000Z

359

Superconducting inductive displacement detection of a microcantilever  

SciTech Connect (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??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.

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

2014-07-21T23:59:59.000Z

360

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

Note: This page contains sample records for the topic "temperature superconducting magnetic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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361

Detection of pico-Tesla magnetic fields using magneto-electric sensors at room temperature  

SciTech Connect (OSTI)

The measurement of low-frequency (10{sup -2}-10{sup 3} Hz) minute magnetic field variations (10{sup -12} Tesla) at room temperature in a passive mode of operation would be critically enabling for deployable neurological signal interfacing and magnetic anomaly detection applications. However, there is presently no magnetic field sensor capable of meeting all of these requirements. Here, we present new bimorph and push-pull magneto-electric laminate composites, which incorporate a charge compensation mechanism (or bridge) that dramatically enhances noise rejection, enabling achievement of such requirements.

Zhai Junyi; Xing Zengping; Dong Shuxiang; Li Jiefang; Viehland, D. [Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

2006-02-06T23:59:59.000Z

362

JOURNAL DE PHYSIQUE CoZZoque C8, suppZ6ment au n08, Tome 41, aoiit 1980, page C8-745 LOW TEMPERATURE THERMAL PROPERTIES OF AMORPHOUS SUPERCONDUCTING ZrCu  

E-Print Network [OSTI]

TEMPERATURE THERMAL PROPERTIES OF AMORPHOUS SUPERCONDUCTING ZrCu H.v. ~Ehneysen,M. Platte, W. Sander, H- applications - from two major points: (1) the investigation of superconductinq properties yields information the superconductinp transition temperatufe Tc, the condensation of electronic quasiparticles permits access

Paris-Sud XI, Université de

363

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

364

Superconductive tunnel junction integrated circuit  

SciTech Connect (OSTI)

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

365

Achievement of a record electron temperature for a magnetic mirror device  

E-Print Network [OSTI]

We demonstrate plasma discharges with extremely high temperature of bulk electrons at the large axially symmetric magnetic mirror device GDT (Budker Institute, Novosibirsk). According to Thomson scattering measurements, the on-axis electron temperature averaged over several sequential shots is 660 $\\pm$ 50 eV with peak values exceeding 900 eV in few shots. This corresponds to at least threefold increase as compared to previous experiments both at the GDT and at other comparable machines, thus demonstrating the maximum quasi-stationary (~1 ms) electron temperature achieved in open traps. The breakthrough is made possible with application of sophisticated electron cyclotron resonance heating in addition to standard heating by neutral beams. The reported increase of the electron temperature along with previous experiments, which demonstrated high-density plasma confinement with $\\beta\\approx$ 60%, provide a firm basis for extrapolating to fusion relevant applications of open magnetic systems.

Bagryansky, P A; Lizunov, A A; Maximov, V V; Prikhodko, V V; Shalashov, A G; Soldatkina, E I; Solomakhin, A L; Yakovlev, D V

2014-01-01T23:59:59.000Z

366

Superconducting structure  

DOE Patents [OSTI]

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

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

2003-04-01T23:59:59.000Z

367

Superconducting Structure  

DOE Patents [OSTI]

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

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

2005-09-13T23:59:59.000Z

368

Active magnetic regenerator  

DOE Patents [OSTI]

An apparatus and method for refrigeration are disclosed which provides efficient refrigeration over temperature ranges in excess of 20/sup 0/C and which requires no maintenance and is, therefore, usable on an unmanned satellite. The apparatus comprises a superconducting magnet which may be solenoidal. A piston comprising a substance such as a rare earth substance which is maintained near its Curie temperature reciprocates through the bore of the solenoidal magnet. A magnetic drive rod is connected to the piston and appropriate heat sinks are connected thereto. The piston is driven by a suitable mechanical drive such as an electric motor and cam. In practicing the invention, the body of the piston is magnetized and demagnetized as it moves through the magnetic field of the solenoid to approximate any of the following cycles or a condition thereof as well as, potentially, other cycles: Brayton, Carnot, Ericsson, and Stirling. Advantages of the present invention include: that refrigeration can be accomplished over at least a 20/sup 0/C scale at superconducting temperatures as well as at more conventional temperatures; very high efficiency, high reliability, and small size. (LCL)

Barclay, J.A.; Steyert, W.A.

1981-01-27T23:59:59.000Z

369

26 Tesla DC Magnet for Neutron Scattering  

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

Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially-manufactured superconducting magnets and limited to 17 T. A few pulsed magnet systems have been...

370

Theory of spin-fluctuation induced superconductivity in iron-based superconductors  

SciTech Connect (OSTI)

In this dissertation we focus on the investigation of the pairing mechanism in the recently discovered high-temperature superconductor, iron pnictides. Due to the proximity to magnetic instability of the system, we considered short-range spin fluctuations as the major mediating source to induce superconductivity. Our calculation supports the magnetic fluctuations as a strong candidate that drives Cooper-pair formation in this material. We find the corresponding order parameter to be of the so-called ss-wave type and show its evolution with temperature as well as the capability of supporting high transition temperature up to several tens of Kelvin. On the other hand, our itinerant model calculation shows pronounced spin correlation at the observed antiferromagnetic ordering wave vector, indicating the underlying electronic structure in favor of antiferromagnetic state. Therefore, the electronic degrees of freedom could participate both in the magnetic and in the superconducting properties. Our work shows that the interplay between magnetism and superconductivity plays an important role to the understanding of the rich physics in this material. The magnetic-excitation spectrum carries important information on the nature of magnetism and the characteristics of superconductivity. We analyze the spin excitation spectrum in the normal and superconducting states of iron pnictides in the magnetic scenario. As a consequence of the sign-reversed gap structure obtained in the above, a spin resonance mode appears below the superconducting transition temperature. The calculated resonance energy, scaled with the gap magnitude and the magnetic correlation length, agrees well with the inelastic neutron scattering (INS) measurements. More interestingly, we find a common feature of those short-range spin fluctuations that are capable of inducing a fully gapped ss state is the momentum anisotropy with elongated span along the direction transverse to the antiferromagnetic momentum transfer. This calculated intrinsic anisotropy exists both in the normal and in the superconducting state, which naturally explains the elliptically shaped magnetic responses observed in INS experiments. Our detailed calculation further shows that the magnetic resonance mode exhibits an upward dispersion-relation pattern but anisotropic along the transverse and longitudinal directions. We also perform a qualitative analysis on the relationship between the anisotropic momentum structure of the magnetic fluctuations and the stability of superconducting phase by intraorbital but interband pair scattering to show the consistency of the magnetic mechanism for superconductivity. As discussed for cuprates, an important identification of the mediating boson is from the fermionic spectrum. We study the spectral function in the normal and superconducting state. Not only do we extract the gap magnitude on the electron- and hole-pockets to show the momentum structure of the gap, but also find a peak-dip-hump feature in the electron spectrum, which reflects the feedback from the spin excitations on fermions. This serves as an interpretation of the kink structure observed in ARPES measurements.

Zhang, Junhua

2011-08-15T23:59:59.000Z

371

Stability and Quench Protection for HTS Superconducting Magnets: Cooperative Research and Development Final Report, CRADA number CRD-05-00160  

SciTech Connect (OSTI)

NREL will perform deposition and testing of various dielectrics on high-temperature superconductors.

Ginley, D. S.

2010-07-01T23:59:59.000Z

372

Design of A Conduction-cooled 4T Superconducting Racetrack for Multi-field Coupling Measurement System  

E-Print Network [OSTI]

A conduction-cooled superconducting magnet producing a transverse field of 4 Tesla has been designed for the new generation multi-field coupling measurement system, which was used to study the mechanical behavior of superconducting samples at cryogenic temperature and intense magnetic fields. Considering experimental costs and coordinating with system of strain measurements by contactless signals (nonlinear CCD optics system), the racetrack type for the coil winding was chosen in our design, and a compact cryostat with a two-stage GM cryocooler was designed and manufactured for the superconducting magnet. The magnet was composed of a pair of flat racetrack coils wound by NbTi/Cu superconducting composite wires, a copper and stainless steel combinational form and two Bi2Sr2CaCu2Oy superconducting current leads. All the coils were connected in series and can be powered with a single power supply. The maximum central magnetic field is 4 T. In order to support the high stress and uniform thermal distribution in t...

Chen, Yuquan; Wu, Wei; Guan, Mingzhi; Wu, Beimin; Mei, Enming; Xin, Canjie

2015-01-01T23:59:59.000Z

373

Inelastic neutron scattering study of a nonmagnetic collapsed tetragonal phase of CaFe2As2: Evidence of the impact of spin fluctuations on superconductivity in the iron-arsenide compounds.  

SciTech Connect (OSTI)

The relationship between antiferromagnetic spin fluctuations and superconductivity has become a central topic of research in studies of superconductivity in the iron pnictides. We present unambiguous evidence of the absence of magnetic fluctuations in the non-superconducting collapsed tetragonal phase of CaFe2As2 via inelas- tic neutron scattering time-of-flight data, which is consistent with the view that spin fluctuations are a necessary ingredient for unconventional superconductivity in the iron pnictides. We demonstrate that the collapsed tetrag- onal phase of CaFe2As2 is non-magnetic, and discuss this result in light of recent reports of high-temperature superconductivity in the collapsed tetragonal phase of closely related compounds.

Soh, Jing Han [ORNL] [ORNL; Tucker, G. S. [Ames Laboratory and Iowa State University] [Ames Laboratory and Iowa State University; Pratt, Daniel K [ORNL] [ORNL; Abernathy, Douglas L [ORNL] [ORNL; Stone, Matthew B [ORNL] [ORNL; Ran, S. [Ames Laboratory and Iowa State University] [Ames Laboratory and Iowa State University; Budko, S L [Ames Laboratory and Iowa State University] [Ames Laboratory and Iowa State University; Canfield, P. C. [Ames Laboratory] [Ames Laboratory; Kreyssig, A. [Ames Laboratory and Iowa State University] [Ames Laboratory and Iowa State University; McQueeney, R. J. [Ames Laboratory] [Ames Laboratory; Goldman, A. I. [Ames Laboratory and Iowa State University] [Ames Laboratory and Iowa State University

2013-01-01T23:59:59.000Z

374

Helical superconducting black holes  

E-Print Network [OSTI]

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

Aristomenis Donos; Jerome P. Gauntlett

2012-05-17T23:59:59.000Z

375

Method for preparing high cure temperature rare earth iron compound magnetic material  

DOE Patents [OSTI]

Insertion of light elements such as H,C, or N in the R.sub.2 Fe.sub.17 (R=rare earth metal) series has been found to modify the magnetic properties of these compounds, which thus become prospective candidates for high performance permanent magnets. The most spectacular changes are increases of the Curie temperature, T.sub.c, of the magnetization, M.sub.s, and of coercivity, H.sub.c, upon interstitial insertion. A preliminary product having a component R--Fe--C,N phase is produced by a chemical route. Rare earth metal and iron amides are synthesized followed by pyrolysis and sintering in an inert or reduced atmosphere, as a result of which, the R--Fe--C,N phases are formed. Fabrication of sintered rare earth iron nitride and carbonitride bulk magnet is impossible via conventional process due to the limitation of nitridation method.

Huang, Yuhong (West Hills, CA); Wei, Qiang (West Hills, CA); Zheng, Haixing (Oak Park, CA)

2002-01-01T23:59:59.000Z

376

Superconducting phase qubits  

E-Print Network [OSTI]

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

Martinis, John M.

2009-01-01T23:59:59.000Z

377

Superconducting phase qubits  

E-Print Network [OSTI]

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

Martinis, John M.

2009-01-01T23:59:59.000Z

378

The Progress on Low-Cost, High-Quality, High-Temperature Superconducting Tapes Deposited by the Combustion Chemical Vapor Deposition Process  

SciTech Connect (OSTI)

The innovative Combustion Chemical Vapor Deposition (CCVD) process is a non-vacuum technique that is being investigated to enable next generation products in several application areas including high-temperature superconductors (HTS). In combination with the Rolling Assisted Biaxially Textured Substrate (RABiTS) technology, the CCVD process has significant promise to provide low-cost, high-quality lengths of YBCO coated conductor. Over 100 meter lengths of both Ni and Ni-W (3 at. Wt.%) substrates with a surface roughness of 12-18 nm were produced. The CCVD technology has been used to deposit both buffer layer coatings as well as YBCO superconducting layers. Buffer layer architecture of strontium titanate (SrTiO{sub 3}) and ceria (CeO{sub 2}) have been deposited by CCVD on textured nickel substrates and optimized to appropriate thicknesses and microstructures to provide templates for growing PLD YBCO with a J{sub c} of 1.1 MA/cm{sup 2} at 77 K and self-field. The CCVD buffer layers have been scaled to meter plus lengths with good epitaxial uniformity along the length. A short sample cut from one of the lengths enabled high critical current density PLD YBCO. Films of CCVD YBCO superconductors have been grown on single crystal substrates with critical current densities over 1 MA/cm{sup 2}. In addition, superconducting YBCO films with an I{sub c} of 60 A/cm-width (J{sub c} = 1.5 MA/cm{sup 2}) were grown on ORNL RABiTS (CeO{sub 2}/YSZ/Y{sub 2}O{sub 3}/Ni/Ni-3W) using CCVD process.

Shoup, S.S.; White, M.K.; Krebs, S.L.; Darnell, N.; King, A.C.; Mattox, D.S.; Campbell, I.H.; Marken, K.R.; Hong, S.; Czabaj, B.; Paranthaman, M.; Christen, H.M.; Zhai, H.-Y. Specht, E.

2008-06-24T23:59:59.000Z

379

Study of the effects of high temperatures during quenches on the performance of a small Nb(3)Sn racetrack magnet  

SciTech Connect (OSTI)

Several high field Nb{sub 3}Sn magnets of different design are under development for future particle accelerators. The high levels of stored energy in these magnets and the high current densities in the conductor can cause high peak temperatures during a quench. The thermal gradients generated in the epoxy-impregnated magnet coils during the fast temperature rise can result in high thermo-mechanical stresses. Considering the sensitivity of Nb{sub 3}Sn to strain and epoxy cracks, it is important to define a maximum acceptable temperature in the coils during a quench which does not cause degradation of the magnet performance. A program was launched at Fermilab to study the effects of thermo-mechanical stress in Nb{sub 3}Sn coils, supported by experiments and by analysis. In collaboration with LBNL, a sub-scaled magnet was built and instrumented to measure the effect of the thermo-mechanical shock during magnet quenches. The magnet consisted of two racetrack coils, assembled in a common coil configuration with a small gap in between. During the test, the magnet reached the maximum field of {approx} 11 T at the short sample current of 9100 A. Temperature excursions up to 400 K did not diminish the magnet quench performance; only after temperature excursions over 430 K, the magnet showed detraining effects, which reduced occasionally the quench current of about 6%. Signs of irreversible degradation (reducing the maximum current of about 3%) appeared only after temperature excursions over 550 K.

Linda Imbasciati et al.

2004-03-23T23:59:59.000Z

380

Superconductivity in SrNi2P2 single crystals  

SciTech Connect (OSTI)

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

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Longitudinal Proximity Effects in Superconducting Transition-Edge Sensors  

SciTech Connect (OSTI)

We have found experimentally that the critical current of a square thin-film superconducting transition-edge sensor (TES) depends exponentially upon the side length L and the square root of the temperature T, a behavior that has a natural theoretical explanation in terms of longitudinal proximity effects if the TES is regarded as a weak link between superconducting leads. As a consequence, the effective transition temperature T{sub c} of the TES is current dependent and at fixed current scales as 1/L{sup 2}. We have also found that the critical current can show clear Fraunhofer-like oscillations in an applied magnetic field, similar to those found in Josephson junctions. We have observed the longitudinal proximity effect in these devices over extraordinarily long lengths up to 290 {micro}m, 1450 times the mean-free path.

Sadleir, John E.; Smith, Stephen J.; Bandler, Simon R.; Chervenak, James A.; Clem, John R.

2010-01-29T23:59:59.000Z

382

Fabrication and Characterization of Nano-Sized Magnetic Structures and Their Flux-Pinning Effects on Superconducting Thin Films  

E-Print Network [OSTI]

Energy Dissipation due to Vortex Motion .................................. 7 Vortex Pinning in the Ferromagnet-Superconductor Hybrid (FSH) . 9 II FABRICATION OF EMBEDDED FERROMAGNET..., as the external magnetic field increases above the lower critical field and below an upper critical field ??2 (?), the magnetic flux partially penetrates the sample in the form of tubes, or vortices (Fig.4). This state is said to be a vortex state or mixed...

Lee, Han Gil

2011-02-22T23:59:59.000Z

383

ac superconducting power: Topics by E-print Network  

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

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

384

Study on the energy criterion of cuprate superconductivity  

E-Print Network [OSTI]

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

Gu Jiapu

2010-02-09T23:59:59.000Z

385

2840 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 21, NO. 3, JUNE 2011 Angular, Temperature, and Strain Dependencies of  

E-Print Network [OSTI]

. It is valuable for many applications such as power cables, transformers, motors, generators and high field temperature supercon- ducting (HTS) tape is the anisotropy which plays a critical Manuscript received August

Hampshire, Damian

386

Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially-manufactured superconducting magnets and limited to 17 T. A  

E-Print Network [OSTI]

Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially, this was the first designed specifically for neutron scattering and the first to include resistive suitable for neutron scattering, diffraction and spectroscopy experiments with the neutron beam passing

Weston, Ken

387

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

SciTech Connect (OSTI)

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

388

Performance of silicon PIN photodiodes at low temperatures and in high magnetic fields  

E-Print Network [OSTI]

The performance of a Si PIN diode (type Hamamatsu S3590-06) as an energy sen- sitive detector operating at cryogenic temperatures (~10 K) and in magnetic fields up to 11 T was investigated, using a 207Bi conversion electron source. It was found that the detector still performs well under these conditions, with small changes in the response function being observed in high magnetic fields, e.g. a 30% to 50% decrease in energy resolution. A GEANT4 Monte Carlo simulation showed that the observed effects are mainly due to the modified trajectories of the electrons due to the influence of the magnetic field, which changes the scattering conditions, rather than to intrinsic changes of the performance of the detector itself.

F. Wauters; I. S. Kraev; M. Tandecki; E. Traykov; S. Van Gorp; D. Zakoucky; N. Severijns

2008-12-31T23:59:59.000Z

389

IEEE TRANSACTIONSON APPLIED SUPERCONDUCTIVITY,VOL. I I, NO. I, MARCH 2001 I223 Magnetic Flux Controlled Josephson Array  

E-Print Network [OSTI]

-dimensional parallel arrays of Josephson junctions have the ability to perform as oscillators tunable hy magnetic flux, Josephsonjunction 1. INTRODUCTION RRAYS of parallel Josephson junctions can operate as Atunable oscillators [I Josephson junction in the array is inodcled using the RCSJ model. The junctions are resistively shunted

Orlando, Terry P.

390

Evidence for entanglement at high temperatures in an engineered molecular magnet  

SciTech Connect (OSTI)

The molecular compound [Fe-2(mu(2)-oxo)(C3H4N2)(6)(C2O4)(2)] was designed and synthesized for the first time and its structure was determined using single-crystal X-ray diffraction. The magnetic susceptibility of this compound was measured from 2 to 300 K. The analysis of the susceptibility data using protocols developed for other spin singlet ground-state systems indicates that the quantum entanglement would remain at temperatures up to 732 K, significantly above the highest entanglement temperature reported to date. The large gap between the ground state and the first-excited state (282 K) suggests that the spin system may be somewhat immune to decohering mechanisms. Our measurements strongly suggest that molecular magnets are promising candidate platforms for quantum information processing.

Reis, Mario S [Universidade Federal Fluminense, Brasil; Soriano, Stephane [Universidade Federal Fluminense, Brasil; Moreira Dos Santos, Antonio F [ORNL; Sales, Brian C [ORNL; Soares-Pinto, D O [Centro Brasileiro de Pesquisas Fisicas (CBPF); Brandao, Paula [University of Aveiro, Portugal

2012-01-01T23:59:59.000Z

391

Evidence for entanglement at high temperatures in an engineered molecular magnet  

E-Print Network [OSTI]

The molecular compound [Fe$_{2}$($\\mu_{2}$-oxo)(C$_{3}$H$_{4}$N$_{2}$)$_{6}$(C$_{2}$O$_{4}$)$_{2}$] was designed and synthesized for the first time and its structure was determined using single-crystal X-ray diffraction. The magnetic susceptibility of this compound was measured from 2 to 300 K. The analysis of the susceptibility data using protocols developed for other spin singlet ground-state systems indicates that the quantum entanglement would remain at temperatures up to 732 K, significantly above the highest entanglement temperature reported to date. The large gap between the ground state and the first-excited state (282 K) suggests that the spin system may be somewhat immune to decohering mechanisms. Our measurements strongly suggest that molecular magnets are promising candidate platforms for quantum information processing.

M. S. Reis; S. Soriano; A. M. dos Santos; B. C. Sales; D. O. Soares-Pinto; P. Brandao

2012-12-07T23:59:59.000Z

392

Numerical investigation of the ion temperature effect in magnetized plasma sheath with two species of positive ions  

SciTech Connect (OSTI)

The effect of ion temperature, magnitude of magnetic field and its orientation on a magnetized plasma sheath consisting of electrons and two species of positive ions are investigated. Using three-fluid hydrodynamic model and some dimensionless variables, the dimensionless equations are obtained and solved numerically. It is found that with the increase of the ion temperature and magnetic field strength there is a significant change in ion densities and energies in the sheath. It is also noticed that increase of magnetic field angle enhances the ion density near the sheath edge for a constant ion temperature. With increase in ion temperature and magnetic field angle, the lighter ion density near the sheath edge enhances and reverses for the heavier ion species.

Shaw, A. K.; Goswami, K. S.; Saikia, B. J. [Centre of Plasma Physics-Institute for Plasma Research, Sonapur-782 402, Guwahati, Kamrup (M) (India); Kar, S. [Institute for Plasma Research, Bhat, Gandhinagar-382 428, Gujarat (India)

2012-01-15T23:59:59.000Z

393

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

E-Print Network [OSTI]

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

Chang, Ho-Myung

394

Coherent growth of superconducting TiN thin films by plasma enhanced molecular beam epitaxy  

SciTech Connect (OSTI)

We have investigated the formation of titanium nitride (TiN) thin films on (001) MgO substrates by molecular beam epitaxy and radio frequency acitvated nitrogen plasma. Although cubic TiN is stabile over a wide temperature range, superconducting TiN films are exclusively obtained when the substrate temperature exceeds 710 Degree-Sign C. TiN films grown at 720 Degree-Sign C show a high residual resistivity ratio of approximately 11 and the superconducting transition temperature (T{sub c}) is well above 5 K. Superconductivity has been confirmed also by magnetiztion measurements. In addition, we determined the upper critical magnetic field ({mu}{sub 0}H{sub c2}) as well as the corresponding coherence length ({xi}{sub GL}) by transport measurements under high magnetic fields. High-resolution transmission electron microscopy data revealed full in plane coherency to the substrate as well as a low defect density in the film, in agreement with a mean-free path length Script-Small-L Almost-Equal-To 106 nm, which is estimated from the residual resistivity value. The observations of reflection high energy electron diffraction intensity oscillations during the growth, distinct Laue fringes around the main Bragg peaks, and higher order diffraction spots in the reciprocal space map suggest the full controlability of the thickness of high quality superconducting TiN thin films.

Krockenberger, Yoshiharu; Karimoto, Shin-ichi; Yamamoto, Hideki; Semba, Kouich [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan)

2012-10-15T23:59:59.000Z

395

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

396

JOURNAL DE PHYSIQUE Colloque C4, supplment au n 4, Tome 40, avril 1979, page C4-138 Superconducting critical field and low temperature heat capacity of ameri-  

E-Print Network [OSTI]

to a sapphire platform that was ther- mally weakly-tied to a 1.38 K liquid helium bath. The heat capacity-138 Superconducting critical field and low temperature heat capacity of ameri- cium (*) J. L. Smith, G. R. Stewart, C on the superconductor americium yield an electronic heat capacity coefficient of y = 2 ±2 mJ/mole · K2 and a critical

Paris-Sud XI, Université de

397

Ten questions and answers about superconductivity  

E-Print Network [OSTI]

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

Tian De Cao

2012-11-13T23:59:59.000Z

398

Investigation of magnetic properties of Fe{sub 3}O{sub 4} nanoparticles using temperature dependent magnetic hyperthermia in ferrofluids  

SciTech Connect (OSTI)

Rate of heat generated by magnetic nanoparticles in a ferrofluid is affected by their magnetic properties, temperature, and viscosity of the carrier liquid. We have investigated temperature dependent magnetic hyperthermia in ferrofluids, consisting of dextran coated superparamagnetic Fe{sub 3}O{sub 4} nanoparticles, subjected to external magnetic fields of various frequencies (188–375 kHz) and amplitudes (140–235 Oe). Transmission electron microscopy measurements show that the nanoparticles are polydispersed with a mean diameter of 13.8?±?3.1?nm. The fitting of experimental dc magnetization data to a standard Langevin function incorporating particle size distribution yields a mean diameter of 10.6?±?1.2?nm, and a reduced saturation magnetization (?65?emu/g) compared to the bulk value of Fe{sub 3}O{sub 4} (?95?emu/g). This is due to the presence of a finite surface layer (?1?nm thickness) of non-aligned spins surrounding the ferromagnetically aligned Fe{sub 3}O{sub 4} core. We found the specific absorption rate, measured as power absorbed per gram of iron oxide nanoparticles, decreases monotonically with increasing temperature for all values of magnetic field and frequency. Using the size distribution of magnetic nanoparticles estimated from the magnetization measurements, we have fitted the specific absorption rate versus temperature data using a linear response theory and relaxation dissipation mechanisms to determine the value of magnetic anisotropy constant (28?±?2?kJ/m{sup 3}) of Fe{sub 3}O{sub 4} nanoparticles.

Nemala, H.; Thakur, J. S.; Lawes, G.; Naik, R., E-mail: rnaik@wayne.edu [Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48202 (United States); Naik, V. M. [Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, Michigan 48128 (United States); Vaishnava, P. P. [Department of Physics, Kettering University, Flint, Michigan 48504 (United States)

2014-07-21T23:59:59.000Z

399

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

400

Ris-R-1578(EN) Design of MgB2 superconducting dipole  

E-Print Network [OSTI]

Risø-R-1578(EN) Design of MgB2 superconducting dipole magnet for particle beam transport-C. Grivel1 and N.H. Andersen1 Title: Design of MgB2 superconducting dipole magnet for particle beam. 2000 char.): A comprehensive analysis of the innovation potential of superconductivity at Risø

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Steady state heat transfer experimental studies of LHC superconducting cables operating in cryogenic environment of superfluid helium  

E-Print Network [OSTI]

The heat management is a basic and fundamental aspect of the superconducting magnets used in the CERN Large Hadron Collider. Indeed, the coil temperature must be kept below the critical value, despite the heat which can be generated or deposited in the magnet during the normal operations. Therefore, this thesis work aims at determining the heating power which can be extracted from the superconducting cables of the LHC, specially through their electrical insulation which represents the main thermal barrier. An experimental measurement campaign in superfluid helium bath was performed on several samples reproducting the main LHC magnets. The heating power was generated in the sample by Joule heating and the temperature increase was measured by means of Cernox bare chip and thermocouples. An innovative instrumentation technique which also includes the in-situ calibration of the thermocouples was developed. A thorough uncertainty analysis on the overall measurement chain concluded the experimental setup. The prese...

Santandrea, Dario; Tuccillo, Raffaele; Granieri, Pier Paolo.

402

Research on ambient temperature passive magnetic bearings at the Lawrence Livermore National Laboratory  

SciTech Connect (OSTI)

Research performed at the Lawrence Livermore National Laboratory on the equilibrium and stability of a new class of ambient-temperature passive bearing systems is described. The basic concepts involved are: (1) Stability of the rotating system is only achieved in the rotating state. That is, disengaging mechanical systems are used to insure stable levitation at rest (when Earnshaw`s theorem applies). (2) Stable levitation by passive magnetic elements can be achieved if the vector sum of the force derivatives of the several elements of the system is net negative (i.e. restoring) for axial, transverse, and tilt-type perturbations from equilibrium. To satisfy the requirements of (2) using only permanent magnet elements we have employed periodic ``Halbach arrays.`` These interact with passive inductive loaded circuits and act as stabilizers, with the primary forces arising from axially symmetric permanent-magnet elements. Stabilizers and other elements needed to create compact passive magnetic bearing systems have been constructed. Novel passive means for stabilizing classes of rotor-dynamic instabilities in such systems have also been investigated.

Post, R.F.; Ryitov, D.D.` Smith, J.R.; Tung, L.S.

1997-04-01T23:59:59.000Z

403

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

E-Print Network [OSTI]

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

Boyer, Edmond

404

The millimeter-wave properties of superconducting microstrip lines  

E-Print Network [OSTI]

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

405

Superconducting Wires Enabled by Nanodots wins Nano50TM Award  

E-Print Network [OSTI]

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

406

Superconducting Properties MgB 2 from First Principles  

E-Print Network [OSTI]

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

Gross, E.K.U.

407

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

408

Electrostatic wave structures in a magnetized superthermal plasma with two-temperature electrons  

SciTech Connect (OSTI)

The linear and nonlinear excitation of arbitrary amplitude ion-acoustic (IA) solitary waves in a magnetized plasma comprising two-temperature electrons and cold ions are studied. The oblique propagation properties of two possible modes (in the linear regime) are investigated. It is found that the electron superthermality reduces the phase velocities of both modes, whereas obliqueness leads to an increase in the separation between two modes. In the nonlinear regime, an energy-like equation describes the evolution of IA solitary waves in the present model. The combined effects of the electron superthermality, magnitude of magnetic field, obliqueness and electron population are incorporated in the study of the existence domain of solitary waves and the soliton characteristics. It is shown that the small values of the hot electron population shift the permitted interval of Mach number to the lower values. Both compressive and rarefactive solitary structures are found to exist in the presence of two temperature electrons. The present investigation contributes to the physics of electrostatic wave structures in Saturn's magnetosphere in which two temperature electrons with kappa distribution exist.

Shahmansouri, M. [Department of Physics, Faculty of Science, Arak University, Arak 38156- 8 8349 (Iran, Islamic Republic of)] [Department of Physics, Faculty of Science, Arak University, Arak 38156- 8 8349 (Iran, Islamic Republic of); Alinejad, H. [Department of Physics, Faculty of Basic Science, Babol University of Technology, Babol 47148-71167 (Iran, Islamic Republic of)] [Department of Physics, Faculty of Basic Science, Babol University of Technology, Babol 47148-71167 (Iran, Islamic Republic of)

2013-08-15T23:59:59.000Z

409

Superconducting dark energy  

E-Print Network [OSTI]

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

Shi-Dong Liang; Tiberiu Harko

2015-04-10T23:59:59.000Z

410

Sensitivity of ultracold atoms to quantized flux in a superconducting ring  

E-Print Network [OSTI]

We report on the magnetic trapping of an ultracold ensemble of $^{87}$Rb atoms close to a superconducting ring prepared in different states of quantized magnetic flux. The niobium ring of 10 $\\mu$m radius is prepared in a flux state $n \\Phi_0$, with $\\Phi_0 = h / 2e$ the flux quantum and $n$ varies between $\\pm 5$. An atomic cloud of 250 nK temperature is positioned with a harmonic magnetic trapping potential at $\\sim 18 \\mu$m distance below the ring. The inhomogeneous magnetic field of the supercurrent in the ring contributes to the magnetic trapping potential of the cloud. The induced deformation of the magnetic trap impacts the shape of the cloud, the number of trapped atoms as well as the center-of-mass oscillation frequency of Bose-Einstein condensates. When the field applied during cooldown of the chip is varied, the change of these properties shows discrete steps that quantitatively match flux quantization.

Weiss, P; Bernon, S; Bothner, D; Sárkány, L; Zimmermann, C; Kleiner, R; Koelle, D; Fortágh, J; Hattermann, H

2015-01-01T23:59:59.000Z

411

Magnetic properties of two-phase superconductors  

E-Print Network [OSTI]

We have recently proposed a theoretical model for superconductors endowed with two distinct superconducting phases, described by two scalar order parameters which condensate at different critical temperatures. On analyzing the magnetic behavior of such systems, we have found some observable differences with respect to the case of ordinary Ginzburg-Landau superconductors. In particular, at low temperature the London penetration length is strongly reduced and the Ginzburg-Landau parameter k becomes a function of temperature. By contrast, in the temperature region between the two phase transitions k is constant and the system is a type-I or a type-II superconductor depending on the ratio between the critical temperatures.

E. Di Grezia; S. Esposito; G. Salesi

2007-09-17T23:59:59.000Z

412

Toward a Holographic Model of Superconducting Fermions  

E-Print Network [OSTI]

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

Andy O'Bannon

2008-11-02T23:59:59.000Z

413

IEFIT - An Interactive Approach to High Temperature Fusion Plasma Magnetic Equilibrium Fitting  

SciTech Connect (OSTI)

An interactive IDL based wrapper, IEFIT, has been created for the magnetic equilibrium reconstruction code EFIT written in FORTRAN. It allows high temperature fusion physicists to rapidly optimize a plasma equilibrium reconstruction by eliminating the unnecessarily repeated initialization in the conventional approach along with the immediate display of the fitting results of each input variation. It uses a new IDL based graphics package, GaPlotObj, developed in cooperation with Fanning Software Consulting, that provides a unified interface with great flexibility in presenting and analyzing scientific data. The overall interactivity reduces the process to minutes from the usual hours.

Peng, Q.; Schachter, J.; Schissel, D.P.; Lao, L.L.

1999-06-01T23:59:59.000Z

414

Magnetic Resonance Flow Velocity and Temperature Mapping of a Shape Memory Polymer Foam Device  

SciTech Connect (OSTI)

Interventional medical devices based on thermally responsive shape memory polymer (SMP) are under development to treat stroke victims. The goals of these catheter-delivered devices include re-establishing blood flow in occluded arteries and preventing aneurysm rupture. Because these devices alter the hemodynamics and dissipate thermal energy during the therapeutic procedure, a first step in the device development process is to investigate fluid velocity and temperature changes following device deployment. A laser-heated SMP foam device was deployed in a simplified in vitro vascular model. Magnetic resonance imaging (MRI) techniques were used to assess the fluid dynamics and thermal changes associated with device deployment. Spatial maps of the steady-state fluid velocity and temperature change inside and outside the laser-heated SMP foam device were acquired. Though non-physiological conditions were used in this initial study, the utility of MRI in the development of a thermally-activated SMP foam device has been demonstrated.

Small IV, W; Gjersing, E; Herberg, J L; Wilson, T S; Maitland, D J

2008-10-29T23:59:59.000Z

415

A 31?T split-pair pulsed magnet for single crystal x-ray diffraction at low temperature  

SciTech Connect (OSTI)

We have developed a pulsed magnet system with panoramic access for synchrotron x-ray diffraction in magnetic fields up to 31?T and at low temperature down to 1.5?K. The apparatus consists of a split-pair magnet, a liquid nitrogen bath to cool the pulsed coil, and a helium cryostat allowing sample temperatures from 1.5 up to 250?K. Using a 1.15?MJ mobile generator, magnetic field pulses of 60?ms length were generated in the magnet, with a rise time of 16.5?ms and a repetition rate of 2 pulses/h at 31?T. The setup was validated for single crystal diffraction on the ESRF beamline ID06.

Duc, F.; Frings, P.; Nardone, M.; Billette, J.; Zitouni, A.; Delescluse, P.; Béard, J.; Nicolin, J. P.; Rikken, G. L. J. A. [Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 143, avenue de Rangueil, F-31400 Toulouse (France); Fabrèges, X. [Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 143, avenue de Rangueil, F-31400 Toulouse (France); Laboratoire Léon Brillouin, UMR12 CEA-CNRS Bât 563 CEA Saclay, 91191 Gif sur Yvette Cedex (France); Roth, T. [European Synchrotron Radiation Facility, Boîte Postale 220, F-38043 Grenoble Cedex (France); European XFEL GmbH, Albert-Einstein-Ring 19, D-22761 Hamburg (Germany); Detlefs, C.; Lesourd, M.; Zhang, L. [European Synchrotron Radiation Facility, Boîte Postale 220, F-38043 Grenoble Cedex (France)

2014-05-15T23:59:59.000Z

416

Ginzburg-Landau Approach to Holographic Superconductivity  

E-Print Network [OSTI]

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

Aldo Dector

2014-12-01T23:59:59.000Z

417

Oxygen-assisted room-temperature deposition of CoPt3 films with perpendicular magnetic anisotropy  

E-Print Network [OSTI]

Oxygen-assisted room-temperature deposition of CoPt3 films with perpendicular magnetic anisotropy B Jolla, California 92093 Received 23 July 2002; accepted 30 September 2002 Trace amounts of oxygen CoPt3 grown by vapor deposition at or slightly above room temperature. Oxygen is known to act

Hellman, Frances

418

Effects of lithium additions on processing of Bi-Sr-Ca-Cu-O superconducting tapes  

SciTech Connect (OSTI)

Lithium additions to the high-temperature superconductor Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (2212) increased superconducting transition temperatures and improved resistance to effects of magnetic fields. In addition, these additions lowered the melting point of 2212 and increased reaction kinetics. Ag-clad tapes fabricated from 2212 with and without Li exhibited profound differences. For heating to temperatures less than or equal to 840{degrees}C, grain growth and sintering were much more substantial in the tapes containing Li.

Goretta, K.C.; Li, Y.F.; Poeppel, R.B. [Argonne National Lab., IL (United States); Wu, S.; Guo, J. [Illinois Univ., Urbana, IL (United States). Dept. of Nuclear Engineering; Schwartz, J. [Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Laboratory

1994-01-01T23:59:59.000Z

419

Molybdenum-rhenium superconducting suspended nanostructures  

SciTech Connect (OSTI)

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

420

Zakharov-Kuznetsov equation in a magnetized plasma with two temperature superthermal electrons  

SciTech Connect (OSTI)

A nonlinear Zakharov-Kuznetsov (ZK) equation for ion-acoustic solitary waves (IASWs) in a magnetized plasmas containing kappa distributed cold and hot electrons is derived by using reductive perturbation method. From the solution of ZK equation, the characteristics of IASWs have been studied under the influence of various plasma parameters. Existence domain of physical parameters is determined. It has been observed that the present plasma system supports the existence of both positive as well as negative potential solitons. The combined effects of cold to hot electron temperature ratio (?), density ratio of cold electrons to ions (f), superthermality of cold and hot electrons (?{sub c},?{sub h}), strength of magnetic field (via ?{sub i}), and obliqueness (?) significantly influence the profile of IASWs. The physical parameters play a great role to modify the width and amplitude of the solitary structures. The stability analysis is also presented in this investigation and parametric range is determined to check the presence of stable and unstable solitons. The findings of this study are important to the physics of electrostatic wave structures in the Saturn's magnetosphere where two temperature electrons with kappa distribution exist.

Saini, N. S., E-mail: nssaini@yahoo.com; Chahal, B. S., E-mail: chahal-bs@rediffmail.com [Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India); Bains, A. S., E-mail: bainsphysics@yahoo.co.in [Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, School of Space Science and Physics, Shandong University at Weihai, 264209 Weihai (China); Bedi, C., E-mail: bedi-chanchal@yahoo.co.in [Department of Physics, Lyallpur Khalsa College, Jalandhar 144001 (India)

2014-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

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

SciTech Connect (OSTI)

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

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

2014-01-13T23:59:59.000Z

422

Superconducting Topological Insulators  

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

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

423

(Final Draft) Superconducting  

E-Print Network [OSTI]

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

424

aerobic room temperature: Topics by E-print Network  

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

superconducting quantum interference device SQUID-temperature RT sample scanning superconduct- ing quantum interference device SQUID microscopy SSM is a very Weiss, Benjamin P....

425

Flavor Superconductivity & Superfluidity  

E-Print Network [OSTI]

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

Matthias Kaminski

2010-02-25T23:59:59.000Z

426

High Temperature Superconducting Thick Films  

DOE Patents [OSTI]

An article including a substrate, a layer of an inert oxide material upon the surface of the substrate, (generally the inert oxide material layer has a smooth surface, i.e., a RMS roughness of less than about 2 nm), a layer of an amorphous oxide or oxynitride material upon the inert oxide material layer, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the amorphous oxide material layer is provided together with additional layers such as at least one layer of a buffer material upon the oriented cubic oxide material layer or a HTS top-layer of YBCO directly upon the oriented cubic oxide material layer. With a HTS top-layer of YBCO upon at least one layer of a buffer material in such an article, Jc's of 1.4×106 A/cm2 have been demonstrated with projected Ic's of 210 Amperes across a sample 1 cm wide.

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

2005-08-23T23:59:59.000Z

427

Processes yielding high superconducting temperatures  

SciTech Connect (OSTI)

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

428

Low temperature London penetration depth and superfluid density in Fe-based superconductors  

SciTech Connect (OSTI)

The superconducting gap symmetry of the Fe-based superconductors was studied by measurements and analysis of London penetration depth and super uid density. Tunnel diode resonator technique for these measurements was implemented in a dilution refrigerator allowing for the temperatures down to 50 mK. For the analysis of the super uid density, we used both experimental studies of Al-coated samples and original thermodynamic approach based on Rutgers relation. In three systems studied, we found that the superconducting gap at the optimal doping is best described in multi-gap full gap scenario. By performing experiments on samples with arti#12;cially introduced disorder with heavy ion irradiation, we show that evolution of the superconducting transition temperature and of the super uid density are consistent with full-gap sign changing s#6; superconducting state. The superconducting gap develops strong modulation both in the under-doped and the over-doped regimes. In the terminal hole-doped KFe{sub 2}As{sub 2}, both temperature dependence of the super uid density and its evolution with increase of the scattering rate are consistent with symmetry imposed vertical line nodes in the superconducting gap. By comparative studies of hole-doped (Ba,K)Fe{sub 2}As{sub 2} and electron-doped Ca10-3-8, we show that the superconducting gap modulation in the under-doped regime is intrinsic and is not induced by the coexisting static magnetic order.

Kim, Hyunsoo [Ames Laboratory] [Ames Laboratory

2013-05-15T23:59:59.000Z

429

Role of pressure in understanding the anomalous superconductivity in europium (molybdenum)/sub 6/(sulfur)/sub 8/ and (TMTSF)/sub 2/FSO/sub 3/  

SciTech Connect (OSTI)

Both the Chevrel phase compound EuMo/sub 6/S/sub 8/ and the organic material, (TMTSF)/sub 2/FSO/sub 3/ are superconducting only under moderate pressure. In both instances the absence of superconductivity at ambient pressure is directly attributed to a low temperature structural distortion that introduces a gap over all or part of the Fermi surface. The role of pressure is to suppress the transition and thus allow the electrons to condense into the superconducting state. In EuMo/sub 6/S/sub 8/, details of the pressure dependence of both the structural and superconducting transition have been explained on the basis of a competition between a charge density wave-type state and superconductivity. In the case of (TMTSF)/sub 2/FSO/sub 3/ an anion ordering giving rise to a metal-insulator transition is responsible for suppressing superconductivity. The critical magnetic fields of EuMo/sub 6/S/sub 8/ are extremely anomalous and are related to the magnetism of the Eu as well as the structure of the compound.

Wolf, S.A.; Huang, C.Y.; Lacoe, R.C.; Chaikin, P.M.; Fuller, W.W.; Luo, H.L.; Wudl, F.

1983-01-01T23:59:59.000Z

430

High-Temperature Elasticity, Cation Disorder and Magnetic Transition in Magnesioferrite  

SciTech Connect (OSTI)

The elastic moduli of magnesioferrite spinel, MgFe2O4, and their temperature dependence have been determined for the first time by ultrasonic measurements on a polycrystalline specimen. The measurements were carried out at 300 MPa and to 700 C in a gas-medium high-pressure apparatus. On heating, both the elastic bulk (K S) and shear (G) moduli decrease linearly to 350 C. By combining with extant thermal-expansion data, the values for the room-temperature K S and G, and their temperature derivatives are as follows: K 0 = 176.3(7) GPa, G 0 = 80.1(2) GPa, ({partial_derivative}K S/{partial_derivative}T) P = -0.032(3) GPa K-1 and ({partial_derivative}G/{partial_derivative}T) P = -0.012(1) GPa K-1. Between 350 and 400 C, there are abrupt increases of 1.4% in both of the elastic moduli; these closely coincide with the magnetic Curie transition that was observed by thermal analyses at about 360 C.

Antao,S.; Jackson, I.; Li, B.; Kung, J.; Chen, J.; Hassan, I.; Liebermann, R.; Parise, J.

2007-01-01T23:59:59.000Z

431

Design development for the 50mm Superconducting Super Collider dipole cryostat  

SciTech Connect (OSTI)

The cryostat of a Superconducting Super Collider (SSC) dipole magnet consists of all magnet components except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations, and must be manufacturable at low cost. The major components of the cryostat are the vacuum vessel, thermal shields, multilayer insulation system, cryogenic piping, interconnections, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course their expected operating life. This paper describes the design of the current 50mm SSC collider dipole cryostat and includes discussions on the structural and thermal considerations involved in the development of each of the major systems. Where appropriate, comparisons will be made with the 40mm cryostat. 7 refs., 5 figs., 4 tabs.

Nicol, T.H.

1991-03-01T23:59:59.000Z

432

Diamond Magnetometry of Superconducting Thin Films  

E-Print Network [OSTI]

In recent years diamond magnetometers based on the nitrogen-vacancy (NV) center have been of considerable interest for magnetometry applications at the nanoscale. An interesting application which is well suited for NV centers is the study of nanoscale magnetic phenomena in superconducting materials. We employ the magnetic sensitivity of NV centers in diamond to interrogate the magnetic properties of a thin-layer yttrium barium copper oxide (YBCO) superconductor. Using fluorescence-microscopy methods and samples integrated with an NV sensor on a microchip, we measure the temperature of phase transition in the layer to be 70.0(2) K, and the penetration field of vortices to be 46(4) G. We observe the pinning of the vortices in the layer at 65 K, and estimate their density after cooling the sample in a ~ 10 G field to be 0.45(1) \\mu m^{-2}. These measurements are done with a 10 nm thick NV layer, so that high spatial resolution may be enabled in the future. Based on these results, we anticipate that this magnetometer could be useful for imaging the structure and dynamics of vortices. As an outlook, we present a fabrication method for a superconductor chip designed for this purpose.

A. Waxman; H. Schlussel; D. Groswasser; V. M. Acosta; L. -S. Bouchard; D. Budker; R. Folman

2014-02-05T23:59:59.000Z

433

Superconductivity for Electric Systems  

E-Print Network [OSTI]

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

434

Superconductivity for Electric Systems  

E-Print Network [OSTI]

Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period January 1, 2007 to March 31, 2007 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For: Department of Energy Office of Electricity Delivery

435

Superconductivity for Electric Systems  

E-Print Network [OSTI]

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

436

Nuclear spin conversion of water inside fullerene cages detected by low-temperature nuclear magnetic resonance  

SciTech Connect (OSTI)

The water-endofullerene H{sub 2}O@C{sub 60} provides a unique chemical system in which freely rotating water molecules are confined inside homogeneous and symmetrical carbon cages. The spin conversion between the ortho and para species of the endohedral H{sub 2}O was studied in the solid phase by low-temperature nuclear magnetic resonance. The experimental data are consistent with a second-order kinetics, indicating a bimolecular spin conversion process. Numerical simulations suggest the simultaneous presence of a spin diffusion process allowing neighbouring ortho and para molecules to exchange their angular momenta. Cross-polarization experiments found no evidence that the spin conversion of the endohedral H{sub 2}O molecules is catalysed by {sup 13}C nuclei present in the cages.

Mamone, Salvatore, E-mail: s.mamone@soton.ac.uk; Concistrè, Maria; Carignani, Elisa; Meier, Benno; Krachmalnicoff, Andrea; Johannessen, Ole G.; Denning, Mark; Carravetta, Marina; Whitby, Richard J.; Levitt, Malcolm H., E-mail: mhl@soton.ac.uk [School of Chemistry, University of Southampton, Southampton SO17 1BJ (United Kingdom); Lei, Xuegong; Li, Yongjun [Department of Chemistry, Columbia University, New York, New York 10027 (United States)] [Department of Chemistry, Columbia University, New York, New York 10027 (United States); Goh, Kelvin; Horsewill, Anthony J. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)] [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2014-05-21T23:59:59.000Z

437

Experimental evidence of the increased transport due to the wall bounded magnetic drift in low temperature plasma  

SciTech Connect (OSTI)

This paper presents experimental results on plasma transport across the magnetic field (B) in magnetized low-temperature plasma sources. Due to the presence of chamber walls, this transport can be complex even in a non-turbulent regime. In particular, in configurations without cylindrical symmetry, the magnetic drifts tend to be bounded by the chamber walls, thereby inducing plasma asymmetry and reducing magnetic confinement. In this work, we measure electron and ion current densities at metal chamber walls bounding a rectangular magnetic filter and demonstrate that these current densities are asymmetrically nonuniform. We also provide an experimental confirmation of model predictions of increased cross-field electron transport in such filter configuration, scaling as 1/B rather than the classical 1/B{sup 2} scaling.

Gaboriau, F., E-mail: gaboriau@laplace.univ-tlse.fr; Baude, R. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d’énergie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); Hagelaar, G. J. M. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d’énergie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062, Toulouse (France)

2014-05-26T23:59:59.000Z

438

Anomalous Dynamical Line Shapes in a Quantum Magnet at Finite Temperature  

SciTech Connect (OSTI)

The effect of thermal fluctuations on the dynamics of a gapped quantum magnet is studied using inelastic neutron scattering on copper nitrate, a model material for the spin-1/2, one-dimensional (1D) bond alternating Heisenberg chain. A large, highly deuterated, single-crystal sample of copper nitrate is produced using a solution growth method and measurements are made using the high-resolution backscattering spectrometer OSIRIS at the ISIS Facility. Theoretical calculations and numerical analysis are combined to interpret the physical origin of the thermal effects observed in the magnetic spectra. The primary observations are (1) a thermally induced central peak due to intraband scattering, which is similar to Villain scattering familiar from soliton systems in 1D, and (2) the one-magnon quasiparticle pole is seen to develop with temperature into an asymmetric continuum of scattering. We relate this asymmetric line broadening to a thermal strongly correlated state caused by hard-core constraints and quasiparticle interactions. These findings are a counter example to recent assertions of the universality of line broadening in 1D systems and are applicable to a broad range of quantum systems.

Tennant D. A.; James A.; Lake, B.; Essler, F.H.L.; Notbohm, S.; Mikeska, H.-J.; Fielden, J.; Kogerler,, P.; Canfield, P.C.; Telling, M.T.F.

2012-01-04T23:59:59.000Z

439

Superconductivity for electric power systems: Program overview  

SciTech Connect (OSTI)

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

440

Effective theory of color superconductivity  

E-Print Network [OSTI]

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

Deog Ki Hong

2007-07-17T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Quantum network of superconducting qubits through opto-mechanical interface  

E-Print Network [OSTI]

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

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

2015-01-08T23:59:59.000Z

442

Eighth International Magnetic Measurement Workshop (IMMW-8) presentations  

SciTech Connect (OSTI)

This report contains viewgraphs on magnetic field measurements conducted at the superconducting super collider and other accelerators.

NONE

1993-09-01T23:59:59.000Z

443

Ceramic wire and coil made of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} high-temperature superconductor with a critical current density up to 75 A {center_dot}cm{sup {minus}2} at 77 K  

SciTech Connect (OSTI)

Processing parameters are refined and a route is found for fabricating wires, coils, and other lengthy electrotechnical elements form high-temperature superconducting ceramic YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}. The superconducting transition temperature of around 90 K and a critical current density in the terrestrial magnetic field of 35-75 A {center_dot} cm{sup {minus}2} at 77 K characterize the performance of the wire.

Basalaeva, T.S.; Ordan`yan, S.S.; Polonskii, Y.A. [St. Petersburg State Technical Univ. (Russian Federation)] [and others

1995-03-20T23:59:59.000Z

444

A unified theory of superconductivity  

E-Print Network [OSTI]

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

Xiuqing Huang

2008-09-22T23:59:59.000Z

445

Design of a horizontal test cryostat for superconducting RF cavities for the FREIA facility at Uppsala University  

SciTech Connect (OSTI)

Uppsala University is constructing a large scale facility, called FREIA (Facility for Research Instrumentation and Accelerator Development). FREIA includes a helium liquefier and an accelerator test facility and has the capacity to test superconducting radio-frequency (RF) cavities with the same RF system and RF power level as in an accelerator. A central element of FREIA is a horizontal test cryostat connected in closed loop to a helium liquefier. This cryostat can house two fully equipped (tuners, piezo, power coupler, helium tank) superconducting cavities to perform full RF high power tests and operate at temperatures between 1.8 K and 4.2 K. The cryostat is designed to accommodate a large array of superconducting cavities and magnets, among which the European Spallation Source (ESS) type spoke and high-? elliptical cavities as well as TESLA/ILC type elliptical cavities. The present status of the project and the design of the cryostat are reported.

Chevalier, N. R.; Thermeau, J.-P.; Bujard, P.; Junquera, T. [Accelerators and Cryogenic Systems (ACS), 86 rue de Paris, 91400 Orsay (France); Hermansson, L.; Kern, R. Santiago; Ruber, R. [Uppsala University, Department of Physics and Astronomy, 75120 Uppsala (Sweden)

2014-01-29T23:59:59.000Z

446

Magnetic order close to superconductivity in the iron-based layered LaO12xFxFeAs systems  

E-Print Network [OSTI]

that is suppressed by doping with electrons to induce superconductivity9 , there has been no direct evidence of SDW-axis spectrometer at the High Flux Isotope Reactor, Oak Ridge National Laboratory. Figure 1a shows the high, inset). This suggests that a structural phase transition has occurred. For comparison, we note

Chandra, Premi

447

Submicrometer superconducting YBa sub 2 Cu sub 3 O sub 6+x particles made by a low-temperature synthetic route  

SciTech Connect (OSTI)

Evidence suggests that superconducting, orthorhombic YBa{sub 2}Cu{sub 3}O{sub 6+x} (x{ge}0.5) is always produced by oxidation of the oxygen-deficient, tetragonal form (x{le}0.5) of this phase (commonly referred to as 123). A synthetic route whereby solution-derived, carbon-free precursors are decomposed at 650{degrees} to 700{degrees}C in inert atmosphere to yield tetragonal 123 is now available. Appropriate precursors include hydrated oxides derived from the hydrolysis of organometallic solutions and aqueous solution-derived hyponitrites. Subsequent oxidation of the tetragonal phase at 400{degrees}C results in submicrometer particles of orthorhombic 123. Superconductivity ({Tc} onset {approx}87 K) has been confirmed in these materials by both Meissner effect and specific-heat measurements.

Horowitz, H.S.; McLain, S.J.; Sleight, A.W.; Druliner, J.D.; Gai, P.L.; VanKavelaar, M.J. (E.I. du Pont de Nemours and Company, Wilmington, DE (USA)); Wagner, J.L.; Biggs, B.D.; Poon, S.J. (Univ. of Virginia, Charlottesville (USA))

1989-01-06T23:59:59.000Z

448

Synthesis of Superconducting MgB2 Wire, Tapes and Films - Energy...  

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

Marketing SummaryAn innovative process for the fabrication of superconducting MgB2 (magnesium diboride) wire suitable for magnets or electrical power transmission. In addition,...

449

Distinguishing S-plus-minus and S-plus-plus electron pairing symmetries by neutron spin resonances in superconducting Sodium-Iron-Cobalt-Arsenic (transitional temperature = 18 Kelvin)  

SciTech Connect (OSTI)

A determination of the superconducting (SC) electron pairing symmetry forms the basis for establishing a microscopic mechansim for superconductivity. For iron pnictide superconductors, the s{sup {+-}}-pairing symmetry theory predicts the presence of a sharp neutron spin resonance at an energy below the sum of hole and electron SC gap energies (E {le} 2{Delta}). Although the resonances have been observed for various iron pnictide superconductors, they are broad in energy and can also be interpreted as arising from the s{sup ++}-pairing symmetry with E {ge} 2{Delta}. Here we use inelastic neutron scattering to reveal a sharp resonance at E = 7 meV in the SC NaFe{sub 0.935}Co{sub 0.045}As (T{sub c} = 18 K). By comparing our experiments with calculated spin-excitations spectra within the s{sup {+-}} and s{sup ++}-pairing symmetries, we conclude that the resonance in NaFe{sub 0.935}Co{sub 0.045}As is consistent with the s{sup {+-}}-pairing symmetry, thus eliminating s{sup ++}-pairing symmetry as a candidate for superconductivity.

Das, Tanmoy [Los Alamos National Laboratory; Balatsky, Alexander V. [Los Alamos National Laboratory; Zhang, Chenglin [University of Tennessee, Knoxville, Tennessee; Li, Haifeng [Institut fur Festkorperforschung, Julich, Germany; Su, Yiki [The University of Tennessee, Knoxville, Tennessee; Nethertom, Tucker [The University of Tennessee, Knoxville, Tennessee; Redding, Caleb [The University of Tennessee, Knoxville, Tennessee; Carr, Scott [The University of Tennessee, Knoxville, Tennessee; Schneidewind, Astrid [Forschungsneutronenquelle Heinz, Garching, Germany; Faulhaber, Enrico [Gemeinsame Forschergruppe HZB, Berlin, Germany; Li, Shiliang [Institute of Physics, Chinese Academy of Sciences, Beijing, China; Yao, Daoxin [Sun Yat-Sen University, Guangzhou, China; Bruckel, Thomas [Institut fur Festkorperforschung, Julich, Germany; Dai, Pengchen [Institute of Physics, Chinese Academy of Sciences, Beijing, China; Sobolev, Oleg [Forschungsneutronenquelle Heinz, Garching, Germany

2012-06-05T23:59:59.000Z

450

Nano-superconducting quantum interference devices with suspended junctions  

SciTech Connect (OSTI)

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

451

A new boson-fermion model of superconductivity  

E-Print Network [OSTI]

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

Tian De Cao

2012-10-09T23:59:59.000Z

452

hal-00258511,version1-22Feb2008 FFLO state in thin superconducting films  

E-Print Network [OSTI]

hal-00258511,version1-22Feb2008 FFLO state in thin superconducting films A. Buzdin1 , Y. Matsuda2 in thin superconducting films in the parallel magnetic field. For the tetragonal crystal symmetry superconducting state the critical field should be isotropic. The mag- netic field pins also the direction

Paris-Sud XI, Université de

453

IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING (IN SUBMISSION) 1 Blind Source Separation for the Superconducting  

E-Print Network [OSTI]

for the Superconducting Imaging-Surface Magnetoencephalography System Keeran Maharajh, Sung Chan Jun, Barak A. Pearlmutter compared to those from its surroundings. A system based on SQUIDs (Superconducting Quantum Interference a superconducting lead (Pb) surface which shields the sensors from external magnetic fields. Since the signals

Pearlmutter, Barak

454

Low-temperature magnetization in Ni-rich gamma-Ni100-x-yFexVy alloys  

E-Print Network [OSTI]

Detailed studies of the temperature dependence of the spontaneous magnetization have been made in eight different compositions of gamma-Ni100-x-yFexVy (4 less than or equal to x less than or equal to 17; 2 less than or equal to y less than or equal...

Chakraborty, S.; Mukherjee, GD; Rathnayaka, KDD; Naugle, Donald G.; Majumdar, AK.

2000-01-01T23:59:59.000Z

455

Superconducting dark energy  

E-Print Network [OSTI]

Based on the analogy with superconductor physics we consider a scalar-vector-tensor gravitational model, in which the dark energy action is described by a gauge invariant electromagnetic type functional. By assuming that the ground state of the dark energy is in a form of a condensate with the U(1) symmetry spontaneously broken, the gauge invariant electromagnetic dark energy can be described in terms of the combination of a vector and of a scalar field (corresponding to the Goldstone boson), respectively. The gravitational field equations are obtained by also assuming the possibility of a non-minimal coupling between the cosmological mass current and the superconducting dark energy. The cosmological implications of the dark energy model are investigated for a Friedmann-Robertson-Walker homogeneous and isotropic geometry for two particular choices of the electromagnetic type potential, corresponding to a pure electric type field, and to a pure magnetic field, respectively. The time evolution of the scale fact...

Liang, Shi-Dong

2015-01-01T23:59:59.000Z

456

The Calculated and Measured Resistance for Splices between Conductors in a MICE Superconducting Coil  

SciTech Connect (OSTI)

The resistance of superconducting joints within MICE coils is an important issue particularly for the coupling coils. The MICE tracker solenoids have only two superconducting joints in the three spectrometer set (end coil 1, the center coil and end coil 2). The AFC magnets may have only a single joint within the coil. The coupling coils may have as many as fifteen joints within the coil, due to relatively short piece lengths of the superconductor. LBNL and ICST looked at three types of coil joints. They are: (1) cold fusion butt joints, (2) side-by-side lap joints, and (3) up-down lap joints. A theoretical calculation of the joint resistance was done at LBNL and checked by ICST. After looking at the theoretical resistance of the three types of joints, it was decided that the cold welded butt joint was not an attractive alternative for joints within a MICE superconducting magnet coil. Side-by-side and up-down lap joints were fabricated at ICST using two types of soft solder between the conductors. These conductor joints were tested at LBNL at liquid helium temperatures over a range of magnetic fields. The joint resistance was compared with the theoretical calculations. Measurements of splice strength were also made at 300 K and 77 K.

Green, Michael A.; Dietderich, Dan; Higley, Hugh; Pan, Heng; Tam, Darren; Trillaud, Federic; Wang, Li; Wu, Hong; Xu, Feng Yu

2009-03-19T23:59:59.000Z

457

Flux pinning characteristics in cylindrical ingot niobium used in superconducting radio frequency cavity fabrication  

SciTech Connect (OSTI)

We present the results of from DC magnetization and penetration depth measurements of cylindrical bulk large-grain (LG) and fine-grain (FG) niobium samples used for the fabrication of superconducting radio frequency (SRF) cavities. The surface treatment consisted of electropolishing and low temperature baking as they are typically applied to SRF cavities. The magnetization data were fitted using a modified critical state model. The critical current density Jc and pinning force Fp are calculated from the magnetization data and their temperature dependence and field dependence are presented. The LG samples have lower critical current density and pinning force density compared to FG samples which implies a lower flux trapping efficiency. This effect may explain the lower values of residual resistance often observed in LG cavities than FG cavities.

Dhavale Ashavai, Pashupati Dhakal, Anatolii A Polyanskii, Gianluigi Ciovati

2012-04-01T23:59:59.000Z

458

Fabrication of Chemically Doped, High Upper Critical Field Magnesium Diboride Superconducting Wires  

SciTech Connect (OSTI)

Controlled chemical doping of magnesium diboride (MgB2) has been shown to substantially improve its superconducting properties to the levels required for high field magnets, but the doping is difficult to accomplish through the usual route of solid state reaction and diffusion. Further, superconducting cables of MgB2 are difficult to fabricate because of the friable nature of the material. In this Phase I STTR project, doped and undoped boron fibers were made by chemical vapor deposition (CVD). Several >100m long batches of doped and undoped fiber were made by CVD codeposition of boron plus dopants. Bundles of these fibers infiltrated with liquid magnesium and subsequently converted to MgB2 to form Mg-MgB2 metal matrix composites. In a parallel path, doped boron nano-sized powder was produced by a plasma synthesis technique, reacted with magnesium to produce doped MgB2 superconducting ceramic bodies. The doped powder was also fabricated into superconducting wires several meters long. The doped boron fibers and powders made in this program were fabricated into fiber-metal composites and powder-metal composites by a liquid metal infiltration technique. The kinetics of the reaction between boron fiber and magnesium metal was investigated in fiber-metal composites. It was found that the presence of dopants had significantly slowed the reaction between magnesium and boron. The superconducting properties were measured for MgB2 fibers and MgB2 powders made by liquid metal infiltration. Properties of MgB2 products (Jc, Hc2) from Phase I are among the highest reported to date for MgB2 bulk superconductors. Chemically doped MgB2 superconducting magnets can perform at least as well as NbTi and NbSn3 in high magnetic fields and still offer an improvement over the latter two in terms of operating temperature. These characteristics make doped MgB2 an effective material for high magnetic field applications, such as magnetic confined fusion, and medical MRI devices. Developing fusion as an energy source will dramatically reduce energy costs, global warming, and radioactive waste. Cheaper and more efficient medical MRI devices could lower examination costs, find potential health problems earlier, and thus also benefit society as a whole. Other potential commercial applications for this material are devices for the generation and storage of electrical power, thus lowering the cost of delivered electricity.

Marzik, James, V.

2005-10-13T23:59:59.000Z

459

Type-I superconductivity and neutron star precession  

E-Print Network [OSTI]

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

Armen Sedrakian

2005-03-30T23:59:59.000Z

460

Brookhaven-Built Magnet Will Catch Subatomic Debris  

ScienceCinema (OSTI)

Peter Wanderer, head of Brookhaven's Superconducting Magnet Division, describes the magnet that's being built for the Facility for Rare Isotope Beams at Michigan State University

Peter Wanderer

2013-07-22T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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.


461

Optimal Magnetic Shield Design with Second–Order Cone ...  

E-Print Network [OSTI]

motors. Each car is equipped with several super-conducting magnet units .... [A3] Ferromagnetic material has saturated magnetic flux density Bs (unit: Tesla =.

2002-10-31T23:59:59.000Z

462

Inelastic Neutron Scattering Study of a Nonmagnetic Collapsed Tetragonal Phase in Nonsuperconducting CaFe2As2: Evidence of the Impact of Spin Fluctuations on Superconductivity in the Iron-Arsenide Compounds  

SciTech Connect (OSTI)

The relationship between antiferromagnetic spin fluctuations and superconductivity has become a central topic of research in studies of superconductivity in the iron pnictides. We present unambiguous evidence of the absence of magnetic fluctuations in the nonsuperconducting collapsed tetragonal phase of CaFe2As2 via inelastic neutron scattering time-of-flight data, which is consistent with the view that spin fluctuations are a necessary ingredient for unconventional superconductivity in the iron pnictides. We demonstrate that the collapsed tetragonal phase of CaFe2As2 is nonmagnetic, and discuss this result in light of recent reports of high-temperature superconductivity in the collapsed tetragonal phase of closely related compounds.

Soh, Jing-Han [Ames Laboratory; Tucker, Ggregory S. [Ames Laboratory; Pratt, Daniel K. [Ames Laboratory; Abernathy, D. L. [Oak Ridge National Laboratory; Stone, M. B. [Oak Ridge National Laboratory; Ran, Sheng [Ames Laboratory; Budko, Sergey L. [Ames Laboratory; Canfield, Paul C. [Ames Laboratory; Kreyssig, Andreas [Ames Laboratory; McQueeney, Robert J. [Ames Laboratory; Goldman, Alan I. [Ames Laboratory

2013-11-27T23:59:59.000Z

463

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... May 1970) In order to estimate the influence of both surface and interface effects on phonon frequencies and superconducting transition temperatures in layered structures, we have calculated the vibrational modes of structures composed...

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

1970-01-01T23:59:59.000Z

464

anisotropic superconducting transition: Topics by E-print Network  

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

j and the magnetic field H in Bi2Sr2CaCu2O8 x ceramics. We provided in high-Tc superconduct- ing granular ceramics remain an intriguing subject of inten- sive investigations...

465

Temperature and magnetic field dependent optical spectral weight in the cation-deficient colossal-magnetoresistance material La0.936Mn0.982O3  

E-Print Network [OSTI]

with the general arguments, a broad peak has been observed in 1 various Mn-based CMR materials by several groupsTemperature and magnetic field dependent optical spectral weight in the cation-deficient colossal on single-crystal samples as a function of temperature and at zero and 0.5 T magnetic fields

Homes, Christopher C.

466

Nuclear magnetic ordering in Ca(OH)2. III. Experimental determination of the critical temperature  

E-Print Network [OSTI]

1479 Nuclear magnetic ordering in Ca(OH)2. III. Experimental determination of the critical(OH)2 is presented. The ordered phase is reached via dynamic nuclear polarization followed to the effective magnetic field are used to determine the magnetic phase of the nuclear spin system. From

Paris-Sud XI, Université de

467

Design considerations of a power supply system for fast cycling superconducting accelerator magnets of 2 Tesla b-field generated by a conductor of 100 kA current  

SciTech Connect (OSTI)

Recently proposed fast cycling accelerators for proton drivers (SF-SPS, CERN and SF-MR, SF-BOOSTER, FNAL) neutrino sources require development of new magnet technology. In support of this magnet development a power supply system will need to be developed that can support the high current and high rate of power swing required by the fast cycling (1 sec rise and fall in the SF-MR, 5Hz in Booster). This paper will outline a design concept for a +/- 2000 V and 100,000 A fast ramping power supply system. This power supply design is in support of a 6.44 km magnet system at 0.020 H and 330 m 5 Hz, 0.00534 H superconducting loads. The design description will include the layout and plan for extending the present FNAL Main Injector style ramping power supply to the higher currents needed for this operation. This will also include the design for a harmonic filter and power factor corrector that will be needed to control the large power swings caused by the fast cycle time. A conceptual design for the current regulation system and control will also be outlined. The power circuit design will include the bridge, filter and transformer plan based on existing designs.

Hays, Steve; Piekarz, Henryk; Pfeffer, Howie; Claypool, Brad; /Fermilab

2007-06-01T23:59:59.000Z

468

Role of oxygen vacancies in magnetic properties of LaAlO{sub 3}/SrTiO{sub 3} interface  

SciTech Connect (OSTI)

The interface of two band-insulators SrTiO{sub 3} and LaAlO{sub 3} exhibits a highly conducting two-dimensional electron gas which shows low-temperature superconductivity, ferromagnetism and many other novel properties. Several studies reveal that the oxygen vacancies at the interface have strong influence on the electronic and magnetic properties of the interface electrons. Here, we develop an insight into the effects of oxygen vacancies on the magnetic properties of the system; the oxygen vacancies help in establishing ferromagnetism which competes with superconductivity at low temperatures. Simulated Monte-Carlo annealing suggests an ordering of the oxygen vacant sites and sheds light on the experimental observation of the quenching of magnetic moment on annealing. A possible explanation for the coexistence of superconductivity and ferromagnetism is also discussed.

Mohanta, N., E-mail: nmohanta@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, West Bengal-721302 (India); Taraphder, A. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, West Bengal-721302, India and Centre for Theoretical Studies, Indian Institute of Technology Kharagpur, West Bengal-721302 (India)

2014-04-24T23:59:59.000Z

469

Superconducting RF Cryomodule Demagnetization  

E-Print Network [OSTI]

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

Crawford, Anthony C

2015-01-01T23:59:59.000Z

470

advanced high-temperature reactor: Topics by E-print Network  

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

of different instabilities that lead to many competing orders. In high-temperature superconduct- ors, besides the superconducting phase, many competing or- ders, such as...

471

activated self-propagating high-temperature: Topics by E-print...  

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

of different instabilities that lead to many competing orders. In high-temperature superconduct- ors, besides the superconducting phase, many competing or- ders, such as...

472

anomalous high-temperature stability: Topics by E-print Network  

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

of different instabilities that lead to many competing orders. In high-temperature superconduct- ors, besides the superconducting phase, many competing or- ders, such as...

473

Basic principle of superconductivity  

E-Print Network [OSTI]

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

Tian De Cao

2009-11-10T23:59:59.000Z

474

Inelastic neutron scattering studies of magnetic fluctuations in the tetragonal and collapsed tetragonal phases of CaFe2As2.  

E-Print Network [OSTI]

??The relationship between magnetism and superconductivity has become a central topic of research in studies of superconductivity in the iron pnictides. This thesis presents inelastic… (more)

Soh, Jing Han

2013-01-01T23:59:59.000Z

475

Instrument for in-situ orientation of superconducting thin-film resonators used for electron-spin resonance experiments  

E-Print Network [OSTI]

When used in Electron-Spin Resonance (ESR) measurements, superconducting thin-film resonators must be precisely oriented relative to the external magnetic field in order to prevent the trapping of magnetic flux and the associated degradation of resonator performance. We present a compact design solution for this problem that allows in-situ control of the orientation of the resonator at cryogenic temperatures. Tests of the apparatus show that when proper alignment is achieved, there is almost no hysteresis in the field dependence of the resonant frequency.

Mowry, Andrew; Kuabsek, James; Friedman, Jonathan R

2015-01-01T23:59:59.000Z

476

Proximity-induced superconductivity in crystalline Cu and Co nanowires and nanogranular Co structures  

SciTech Connect (OSTI)

We report an experimental study of proximity effect-induced superconductivity in crystalline Cu and Co nanowires and a nanogranular Co nanowire structure in contact with a superconducting W-based floating electrode (inducer). For electrical resistance measurements up to three pairs of Pt-based voltage leads were attached at different distances beside the inner inducer electrode, thus allowing us to probe the proximity effect over a length of 2–12??m. Up to 30% resistance drops with respect to the normal-state value have been observed for the crystalline Co and Cu nanowires when sweeping the temperature below T{sub c} of the inducer (5.2?K). By contrast, relative R(T) drops were found to be an order of magnitude smaller for the nanogranular Co nanowire structure. Our analysis of the resistance data shows that the superconducting proximity length in crystalline Cu and Co is about 1??m at 2.4?K, attesting to a long-range proximity effect in the Co nanowire. Moreover, this long-range proximity effect is insusceptible to magnetic fields up to 11?T, which is indicative of spin-triplet pairing. At the same time, proximity-induced superconductivity in the nanogranular Co nanowire is strongly suppressed due to the dominating Cooper pair scattering caused by its intrinsic microstructure.

Kompaniiets, M., E-mail: Kompaniiets@physik.uni-frankfurt.de; Begun, E.; Porrati, F.; Huth, M. [Physikalisches Institut, Goethe University, 60438 Frankfurt am Main (Germany); Dobrovolskiy, O. V. [Physikalisches Institut, Goethe University, 60438 Frankfurt am Main (Germany); Physics Department, V. Karazin National University, 61077 Kharkiv (Ukraine); Neetzel, C.; Ensinger, W. [Department of Materials Science, TU Darmstadt, 64287 Darmstadt (Germany)

2014-08-21T23:59:59.000Z

477

Superconducting Cable Termination  

DOE Patents [OSTI]

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

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

2005-08-30T23:59:59.000Z

478

Improved Magnetic Fusion Energy Economics via Massive Resistive Electromagnets  

SciTech Connect (OSTI)

Abandoning superconductors for magnetic fusion reactors and instead using resistive magnet designs based on cheap copper or aluminum conductor material operating at "room temperature" (300 K) can reduce the capital cost per unit fusion power and simplify plant operations. By increasing unit size well beyond that of present magnetic fusion energy conceptual designs using superconducting electromagnets, the recirculating power fraction needed to operate resistive electromagnets can be made as close to zero as needed for economy without requiring superconductors. Other advantages of larger fusion plant size, such as very long inductively driven pulses, may also help reduce the cost per unit fusion power.

Woolley, R.D.

1998-08-19T23:59:59.000Z

479

Protective link for superconducting coil  

DOE Patents [OSTI]

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

Umans, Stephen D. (Belmont, MA)

2009-12-08T23:59:59.000Z

480

Mechanical and electromagnetic transverse load effects on superconducting niobium-tin performance  

E-Print Network [OSTI]

Cable-in-Conduit Conductor is the typical geometry for the conductor employed in superconducting magnets for fusion applications. Once energized, the magnets produce an enormous electromagnetic force and very large transverse ...

Chiesa, Luisa

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature superconducting magnetic" 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

Temperature-induced martensite in magnetic shape memory Fe{sub 2}MnGa observed by photoemission electron microscopy  

SciTech Connect (OSTI)

The magnetic domain structure in single crystals of a Heusler shape memory compound near the composition Fe{sub 2}MnGa was observed during phase transition by photoelectron emission microscopy at Beamline 11.0.1.1 of the Advanced Light Source. The behavior is comparable with recent observations of an adaptive martensite phase in prototype Ni{sub 2}MnGa, although the pinning in the recent work is an epitaxial interface and in this work the e#11;ective pinning plane is a boundary between martensitic variants that transform in a self-accommodating way from the single crystal austenite phase present at high temperatures. Temperature dependent observations of the twinning structure give information as to the coupling behavior between the magnetism and the structural evolution.

Jenkins, Catherine; Scholl, Andreas; Kainuma, R.; Elmers, Hans-Joachim; Omori, Toshihiro

2012-01-18T23:59:59.000Z

482

Crossovers between superconducting symmetry classes  

E-Print Network [OSTI]

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

V. A. Koziy; M. A. Skvortsov

2011-06-20T23:59:59.000Z

483

Superconductivity at 34 K in the K/Ba/Bi/O system  

SciTech Connect (OSTI)

The critical temperature for superconductivity in the (Ba, K)BiO{sub 3} system has been increased to 34 K. With each such increase of T{sub c} in a system containing no copper it becomes increasingly likely that the mechanisms for superconductivity in the Bi-based and the Cu-based oxide superconductors are very closely related to each other. Since the (Ba, K)BiO{sub 3} superconductors possess the cubic perovskite structure, the mechanism for high T{sub c} would then not related directly to the two-dimensional character of the copper oxide superconductors or to the magnetism in such systems. 12 refs., 1 fig.

Jones, N.L.; Parise, J.B.; Flippen, R.B.; Sleight, A.W. (E.I. DuPont de Nemours and Co., Wilmington, DE (USA))

1989-02-01T23:59:59.000Z

484

Onset of surface superconductivity  

SciTech Connect (OSTI)

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 restriction