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Sample records for high temperature superconductor

  1. High temperature superconductor current leads

    DOE Patents [OSTI]

    Hull, John R.; Poeppel, Roger B.

    1995-01-01

    An electrical lead having one end for connection to an apparatus in a cryogenic environment and the other end for connection to an apparatus outside the cryogenic environment. The electrical lead includes a high temperature superconductor wire and an electrically conductive material distributed therein, where the conductive material is present at the one end of the lead at a concentration in the range of from 0 to about 3% by volume, and at the other end of the lead at a concentration of less than about 20% by volume. Various embodiments are shown for groups of high temperature superconductor wires and sheaths.

  2. High temperature superconductor current leads

    DOE Patents [OSTI]

    Hull, J.R.; Poeppel, R.B.

    1995-06-20

    An electrical lead is disclosed having one end for connection to an apparatus in a cryogenic environment and the other end for connection to an apparatus outside the cryogenic environment. The electrical lead includes a high temperature superconductor wire and an electrically conductive material distributed therein, where the conductive material is present at the one end of the lead at a concentration in the range of from 0 to about 3% by volume, and at the other end of the lead at a concentration of less than about 20% by volume. Various embodiments are shown for groups of high temperature superconductor wires and sheaths. 9 figs.

  3. Fabrication of high temperature superconductors

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Dorris, Stephen E.; Ma, Beihai; Li, Meiya

    2003-06-17

    A method of forming a biaxially aligned superconductor on a non-biaxially aligned substrate substantially chemically inert to the biaxially aligned superconductor comprising is disclosed. A non-biaxially aligned substrate chemically inert to the superconductor is provided and a biaxially aligned superconductor material is deposited directly on the non-biaxially aligned substrate. A method forming a plume of superconductor material and contacting the plume and the non-biaxially aligned substrate at an angle greater than 0.degree. and less than 90.degree. to deposit a biaxially aligned superconductor on the non-biaxially aligned substrate is also disclosed. Various superconductors and substrates are illustrated.

  4. High temperature crystalline superconductors from crystallized glasses

    DOE Patents [OSTI]

    Shi, Donglu

    1992-01-01

    A method of preparing a high temperature superconductor from an amorphous phase. The method involves preparing a starting material of a composition of Bi.sub.2 Sr.sub.2 Ca.sub.3 Cu.sub.4 Ox or Bi.sub.2 Sr.sub.2 Ca.sub.4 Cu.sub.5 Ox, forming an amorphous phase of the composition and heat treating the amorphous phase for particular time and temperature ranges to achieve a single phase high temperature superconductor.

  5. Sealed glass coating of high temperature ceramic superconductors

    DOE Patents [OSTI]

    Wu, Weite; Chu, Cha Y.; Goretta, Kenneth C.; Routbort, Jules L.

    1995-01-01

    A method and article of manufacture of a lead oxide based glass coating on a high temperature superconductor. The method includes preparing a dispersion of glass powders in a solution, applying the dispersion to the superconductor, drying the dispersion before applying another coating and heating the glass powder dispersion at temperatures below oxygen diffusion onset and above the glass melting point to form a continuous glass coating on the superconductor to establish compressive stresses which enhance the fracture strength of the superconductor.

  6. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound...

  7. Pseudogap and Superconducting Gap in High-Temperature Superconductors

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

    Pseudogap and Superconducting Gap in High-Temperature Superconductors Two decades after the discovery of first high temperature superconductors, the microscopic mechanism of high-Tc superconductivity remains elusive. In conventional superconductors, it has been well established that electrons form so-called "Cooper pairs" to give rise to superconductivity. The pair binding manifests itself as an energy gap in many spectroscopic measurements. This energy gap, known as superconducting

  8. Sealed glass coating of high temperature ceramic superconductors

    DOE Patents [OSTI]

    Wu, W.; Chu, C.Y.; Goretta, K.C.; Routbort, J.L.

    1995-05-02

    A method and article of manufacture of a lead oxide based glass coating on a high temperature superconductor is disclosed. The method includes preparing a dispersion of glass powders in a solution, applying the dispersion to the superconductor, drying the dispersion before applying another coating and heating the glass powder dispersion at temperatures below oxygen diffusion onset and above the glass melting point to form a continuous glass coating on the superconductor to establish compressive stresses which enhance the fracture strength of the superconductor. 8 figs.

  9. Particle-hole symmetry broken pseudogap in high temperature superconductors

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

    Particle-hole symmetry broken pseudogap in high temperature superconductors High-temperature (Tc) superconductivity is one of the most important topics in condensed matter physics. Despite extensive studies over more than two decades, the microscopic mechanism of high temperature superconductivity still remains elusive due to many unconventional properties that are not well understood. Among them, the most mysterious behavior of high-Tc superconductor is the nature of so called

  10. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Two Phase Transitions Make a High-Temperature Superconductor Print Wednesday, 30 November 2011 00:00 Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally

  11. DOE Science Showcase - Understanding High-Temperature Superconductors |

    Office of Scientific and Technical Information (OSTI)

    OSTI, US Dept of Energy Office of Scientific and Technical Information Understanding High-Temperature Superconductors Credit: DOE Scientists have long worked to understand one of the great mysteries of modern physics - the origin and behavior of high-temperature superconductors (HTS) that are uniquely capable of transmitting electricity with zero loss when chilled to subzero temperatures. For decades there have been competing theories and misunderstandings of how HTS materials actually work

  12. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  13. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  14. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  15. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  16. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  17. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  18. Two Phase Transitions Make a High-Temperature Superconductor

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

    Two Phase Transitions Make a High-Temperature Superconductor Print Superconductivity-conceptually remarkable and practically revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach this state via a single thermal phase transition at a critical temperature (Tc). It was generally believed that such a picture also applied to the copper oxide (cuprate) superconductors-first

  19. Method of manufacturing a high temperature superconductor with improved transport properties

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Siegel, Richard W.; Askew, Thomas R.

    2001-01-01

    A method of preparing a high temperature superconductor. A method of preparing a superconductor includes providing a powdered high temperature superconductor and a nanophase paramagnetic material. These components are combined to form a solid compacted mass with the paramagnetic material disposed on the grain boundaries of the polycrystaline high temperature superconductor.

  20. Design of High Field Solenoids made of High Temperature Superconductors

    SciTech Connect (OSTI)

    Bartalesi, Antonio; /Pisa U.

    2010-12-01

    This thesis starts from the analytical mechanical analysis of a superconducting solenoid, loaded by self generated Lorentz forces. Also, a finite element model is proposed and verified with the analytical results. To study the anisotropic behavior of a coil made by layers of superconductor and insulation, a finite element meso-mechanic model is proposed and designed. The resulting material properties are then used in the main solenoid analysis. In parallel, design work is performed as well: an existing Insert Test Facility (ITF) is adapted and structurally verified to support a coil made of YBa{sub 2}Cu{sub 3}O{sub 7}, a High Temperature Superconductor (HTS). Finally, a technological winding process was proposed and the required tooling is designed.

  1. Method for fabrication of high temperature superconductors

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Ma, Beihai; Miller, Dean

    2009-07-14

    A layered article of manufacture and a method of manufacturing same is disclosed. A substrate has a biaxially textured MgO crystalline layer having the c-axes thereof inclined with respect to the plane of the substrate deposited thereon. A layer of one or more of YSZ or Y.sub.2O.sub.3 and then a layer of CeO.sub.2 is deposited on the MgO. A crystalline superconductor layer with the c-axes thereof normal to the plane of the substrate is deposited on the CeO.sub.2 layer. Deposition of the MgO layer on the substrate is by the inclined substrate deposition method developed at Argonne National Laboratory. Preferably, the MgO has the c-axes thereof inclined with respect to the normal to the substrate in the range of from about 10.degree. to about 40.degree. and YBCO superconductors are used.

  2. Method for fabrication of high temperature superconductors

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Ma, Beihai; Miller, Dean

    2006-03-14

    A layered article of manufacture and a method of manufacturing same is disclosed. A substrate has a biaxially textured MgO crystalline layer having the c-axes thereof inclined with respect to the plane of the substrate deposited thereon. A layer of one or more of YSZ or Y2O3 and then a layer of CeO2 is deposited on the MgO. A crystalline superconductor layer with the c-axes thereof normal to the plane of the substrate is deposited on the CeO2 layer. Deposition of the MgO layer on the substrate is by the inclined substrate deposition method developed at Argonne National Laboratory. Preferably, the MgO has the c-axes thereof inclined with respect to the normal to the substrate in the range of from about 10.degree. to about 40.degree. and YBCO superconductors are used.

  3. Cryocooler applications for high-temperature superconductor magnetic bearings.

    SciTech Connect (OSTI)

    Niemann, R. C.

    1998-05-22

    The efficiency and stability of rotational magnetic suspension systems are enhanced by the use of high-temperature superconductor (HTS) magnetic bearings. Fundamental aspects of the HTS magnetic bearings and rotational magnetic suspension are presented. HTS cooling can be by liquid cryogen bath immersion or by direct conduction, and thus there are various applications and integration issues for cryocoolers. Among the numerous cryocooler aspects to be considered are installation; operating temperature; losses; and vacuum pumping.

  4. Improved Growth of High-Temperature Superconductors with HF Pressure

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

    Control - Energy Innovation Portal Electricity Transmission Electricity Transmission Find More Like This Return to Search Improved Growth of High-Temperature Superconductors with HF Pressure Control Brookhaven National Laboratory Contact BNL About This Technology Publications: PDF Document Publication A new method of HF control for synthesizing YBCO using the BaF2 ex situ process (83 KB) Graphical representation of the removal of hydrogen fluoride gas by the absorber during growth of

  5. Metallic substrates for high temperature superconductors

    DOE Patents [OSTI]

    Truchan, Thomas G.; Miller, Dean J.; Goretta, Kenneth C.; Balachandran, Uthamalingam; Foley, Robert

    2002-01-01

    A biaxially textured face-centered cubic metal article having grain boundaries with misorientation angles greater than about 8.degree. limited to less than about 1%. A laminate article is also disclosed having a metal substrate first rolled to at least about 95% thickness reduction followed by a first annealing at a temperature less than about 375.degree. C. Then a second rolling operation of not greater than about 6% thickness reduction is provided, followed by a second annealing at a temperature greater than about 400.degree. C. A method of forming the metal and laminate articles is also disclosed.

  6. Nearly Perfect Fluidity in a High Temperature Superconductor

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

    Rameau, J. D.; Reber, T. J.; Yang, H. -B.; Akhanjee, S.; Gu, G. D.; Johnson, P. D.; Campbell, S.

    2014-10-13

    Perfect fluids are characterized as having the smallest ratio of shear viscosity to entropy density, η/s, consistent with quantum uncertainty and causality. So far, nearly perfect fluids have only been observed in the quark-gluon plasma and in unitary atomic Fermi gases, exotic systems that are amongst the hottest and coldest objects in the known universe, respectively. We use angle resolved photoemission spectroscopy to measure the temperature dependence of an electronic analog of η/s in an optimally doped cuprate high-temperature superconductor, finding it too is a nearly perfect fluid around, and above, its superconducting transition temperature Tc.

  7. Nearly Perfect Fluidity in a High Temperature Superconductor

    SciTech Connect (OSTI)

    Rameau, J. D.; Reber, T. J.; Yang, H. -B.; Akhanjee, S.; Gu, G. D.; Johnson, P. D.; Campbell, S.

    2014-10-13

    Perfect fluids are characterized as having the smallest ratio of shear viscosity to entropy density, η/s, consistent with quantum uncertainty and causality. So far, nearly perfect fluids have only been observed in the quark-gluon plasma and in unitary atomic Fermi gases, exotic systems that are amongst the hottest and coldest objects in the known universe, respectively. We use angle resolved photoemission spectroscopy to measure the temperature dependence of an electronic analog of η/s in an optimally doped cuprate high-temperature superconductor, finding it too is a nearly perfect fluid around, and above, its superconducting transition temperature Tc.

  8. Preparation of thin film high temperature superconductors

    SciTech Connect (OSTI)

    VenKatesan, X.X.T.; Li, Q.; Findikoglu, A.; Hemmick, D. . Dept. of Physics); Wu, X.D. ); Inam, A.; Chang, C.C.; Ramesh, R.; Hwang, D.M.; Ravi, T.S.; Etemad, S.; Martinez, J.A.; Wilkens, B. )

    1991-03-01

    This paper addresses fundamental issues in preparing high quality high T{sub c} YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} thin films. The techniques of inverted cylindrical magnetron sputtering and pulsed laser deposition are chosen as successful examples to illustrate how the key problems can be solved. The fabrication of YBa{sub 2}Cu{sub 3}O{sub 7{minus}x}/PrBa{sub 2}Cu{sub 3}O{sub 7{minus}x} superlattices where superconductivity in a single unit cell layer of YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} was observed demonstrates the state of the art of thin film deposition of high T{sub c} materials. Systematic variations of the deposition parameters result in changes of superconducting and structural properties of the films that correlate with their microwave and infrared characteristics.

  9. DOE Science Showcase - Understanding High-Temperature Superconductors...

    Office of Scientific and Technical Information (OSTI)

    Read about HTS technology, basic science and progress towards theory in Dr. William ... Superconductors (Hindawi Publishing), Science Open Access Journals (SOAJ) High ...

  10. Microwave characterization of high-temperature superconductors

    SciTech Connect (OSTI)

    Cooke, D.W.; Gray, E.R.; Arendt, P.N.; Beery, J.G.; Bennett, B.L.; Brown, D.R.; Houlton, R.J.; Jahan, M.S.; Klapetzky, A.J.; Maez, M.A.; Raistrick, I.D.; Reeves, G.A.; Rusnak, B.

    1989-01-01

    Thick (10-15 {mu}m) Tl-Ba-Ca-Cu-O films have been deposited onto yttria-stabilized zirconia and Ag substrates by d.c. magnetron sputtering techniques. Direct deposition onto 1'' diameter yttria-stabilized zirconia yields films with typical 22 GHz surface resistance (R{sub s}) values of 5.2 {plus minus} 2 m{Omega} and 52 {plus minus} 2 m{Omega} at 10 K and 77 K, respectively. For comparison, R{sub s} of Cu at this same frequency is 10 m{Omega} at 4 K and 22 m{Omega} at 77 K. Tl-Ba-Ca-Cu-O films have also been deposited onto 1'' diameter Ag substrates using Au/Cu, Cu, and BaF{sub 2} buffer layers. The lowest R{sub s} values were obtained on films with a BaF{sub 2} buffer layer, typical values being 7.8 {plus minus} 2 m{Omega} and 30.6 {plus minus} 2 m{Omega} (measured at 22 GHz) at 10 K and 77 K, respectively. Larger films (1.5'' diameter) with similar R{sub s} values were prepared using this same technique, demonstrating that the fabrication process can be scaled to larger surface areas. These films are promising for radiofrequency cavity applications because they are thick (50-75 times the London penetration depth), have relatively large surface areas, are fabricated on metallic substrates, and have R{sub s} values that are competitive with Cu at 77 K and are lower than Cu at 4 K. Because they are polycrystalline and unoriented, it is anticipated that their R{sub s} values can be lowered by improving the processing technique. High-quality films of YBa{sub 2}Cu{sub 3}O{sub 7} have been electron-beam deposited onto 1'' LaGaO{sub 3} and 1.5'' LaAlO{sub 3} substrates. The 1'' sample is characterized by R{sub s} values of 0.2 {plus minus} 0.1 m{Omega} at 4 K and 18.6 {plus minus} 2 m{Omega} at 77 K. The 4-K value is only 2-4 times higher than Nb. The 1.5'' sample has R{sub s} values (measured at 18 GHz) of 0.93 {plus minus} 2 m{Omega} and 71 {plus minus} 3 m{Omega} at 10 K and 77 K, respectively. 18 refs., 8 figs.

  11. SCALING OF THE SUPERFLUID DENSITY IN HIGH-TEMPERATURE SUPERCONDUCTORS.

    SciTech Connect (OSTI)

    HOMES, C.C.

    2005-10-24

    A scaling relation N{sub c} {approx} 4.4{sigma}{sub dc}T{sub c} has been observed parallel and perpendicular to the copper-oxygen planes in the high-temperature superconductors; N{sub c} is the spectral weight and {sigma}{sub dc} is the dc conductivity just above the critical temperature T{sub c}. In addition, Nb and Pb also fall close to the this scaling line. The application of the Ferrell-Glover-Tinkham sum rule to the BCS optical properties of Nb above and below T{sub c} yields N{sub c} {approx} 8.1{sigma}{sub dc}T{sub c} when the normal-state scattering rate is much greater than the superconducting energy gap (1/{tau} > 2{Delta}, the ''dirty'' limit). This result implies that the high-temperature superconductors may be in the dirty limit. The superconductivity perpendicular to the planes is explained by the Josephson effect, which again yields N{sub c} {approx} 8.1{sigma}{sub dc}T{sub c} in the BCS formalism. The similar forms for the scaling relation in these two directions suggests that in some regime the dirty limit and the Josephson effect may be viewed as equivalent.

  12. Theory of intertwined orders in high temperature superconductors

    SciTech Connect (OSTI)

    Fradkin, Eduardo; Tranquada, John M.; Kivelson, Steven A.

    2015-03-26

    The electronic phase diagrams of many highly correlated systems, and in particular the cuprate high temperature superconductors, are complex, with many different phases appearing with similarsometimes identicalordering temperatures even as material properties, such as a dopant concentration, are varied over wide ranges. This complexity is sometimes referred to as competing orders. However, since the relation is intimate, and can even lead to the existence of new phases of matter such as the putative pair-density-wave, the general relation is better thought of in terms of intertwined orders. We selectively analyze some of the experiments in the cuprates which suggest that essential aspects of the physics are reflected in the intertwining of multiple ordersnot just in the nature of each order by itself. We also summarize and critique several theoretical ideas concerning the origin and implications of this complexity.

  13. Theory of intertwined orders in high temperature superconductors

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

    Fradkin, Eduardo; Tranquada, John M.; Kivelson, Steven A.

    2015-03-26

    The electronic phase diagrams of many highly correlated systems, and in particular the cuprate high temperature superconductors, are complex, with many different phases appearing with similar—sometimes identical—ordering temperatures even as material properties, such as a dopant concentration, are varied over wide ranges. This complexity is sometimes referred to as “competing orders.” However, since the relation is intimate, and can even lead to the existence of new phases of matter such as the putative “pair-density-wave,” the general relation is better thought of in terms of “intertwined orders.” We selectively analyze some of the experiments in the cuprates which suggest that essentialmore » aspects of the physics are reflected in the intertwining of multiple orders—not just in the nature of each order by itself. We also summarize and critique several theoretical ideas concerning the origin and implications of this complexity.« less

  14. Theory of intertwined orders in high temperature superconductors

    SciTech Connect (OSTI)

    Fradkin, Eduardo; Tranquada, John M.; Kivelson, Steven A.

    2015-03-26

    The electronic phase diagrams of many highly correlated systems, and in particular the cuprate high temperature superconductors, are complex, with many different phases appearing with similar—sometimes identical—ordering temperatures even as material properties, such as a dopant concentration, are varied over wide ranges. This complexity is sometimes referred to as “competing orders.” However, since the relation is intimate, and can even lead to the existence of new phases of matter such as the putative “pair-density-wave,” the general relation is better thought of in terms of “intertwined orders.” We selectively analyze some of the experiments in the cuprates which suggest that essential aspects of the physics are reflected in the intertwining of multiple orders—not just in the nature of each order by itself. We also summarize and critique several theoretical ideas concerning the origin and implications of this complexity.

  15. Studies of nonlinear electrodynamics of high-temperature superconductors

    SciTech Connect (OSTI)

    Lam, Quan-Chiu H.

    1991-08-01

    Nonlinear electrodynamics of high-{Tc} superconductors are studied both theoretically and experimentally. For powdered samples, a novel model is presented in which the metallographically observed superconducting grains in the powder are modeled as superconducting current loops of various areas with weak links. Surprising harmonic generation behavior in an arc field, H{sub 1} cos({omega}t), is predicted by the model; the power at high harmonics show sharp dips almost periodic in a superposing dc magnetic field, revealing flux quantization in the prototype loops in the model. Such oscillation of the harmonic power in dc magnetic field P{sub nf}(H{sub dc}), is indeed experimentally observed in powdered YBa{sub 2}Cu{sub 3}O{sub 7}. Other experimental aspects also agree with model predictions. For bulk sintered cylindrical samples, a generalized critical state model is presented. In this model, the nonlinear electrodynamics are due to flux-pinning, somewhat similar to low-temperature type-II superconductors, but with a more generalized critical current densities' dependence on magnetic field -- J{sub c}(H){approximately}H{sub local}{sup -{beta}}, with {beta} being an adjustable parameter. Experiments in ac and dc magnetic fields on a sintered cylindrical rod of YBa{sub 2}Cu{sub 3}O{sub 7} yield unambiguous evidence of independent inter- and intragranular contributions to the complex harmonic permeability {tilde {mu}}{sub n} = {mu}{prime}{sub n} -i{mu}{double prime}{sub n}. Temperature- dependence measurements reveal that, while the intragranular supercurrents disappear at {Tc}{ge}91.2 K, the intergranular supercurrents disappear at T{ge}86.6 K. This result is, to our knowledge, the first clear measurement of the phase-locking temperature of the 3-D matrix formed by YBa{sub 2}Cu{sub 3}O{sub 7} grains, which are in electrical contact with one another through weak links.

  16. Studies of nonlinear electrodynamics of high-temperature superconductors

    SciTech Connect (OSTI)

    Lam, Quan-Chiu H.

    1991-08-01

    Nonlinear electrodynamics of high-{Tc} superconductors are studied both theoretically and experimentally. For powdered samples, a novel model is presented in which the metallographically observed superconducting grains in the powder are modeled as superconducting current loops of various areas with weak links. Surprising harmonic generation behavior in an arc field, H{sub 1} cos({omega}t), is predicted by the model; the power at high harmonics show sharp dips almost periodic in a superposing dc magnetic field, revealing flux quantization in the prototype loops in the model. Such oscillation of the harmonic power in dc magnetic field P{sub nf}(H{sub dc}), is indeed experimentally observed in powdered YBa{sub 2}Cu{sub 3}O{sub 7}. Other experimental aspects also agree with model predictions. For bulk sintered cylindrical samples, a generalized critical state model is presented. In this model, the nonlinear electrodynamics are due to flux-pinning, somewhat similar to low-temperature type-II superconductors, but with a more generalized critical current densities` dependence on magnetic field -- J{sub c}(H){approximately}H{sub local}{sup -{beta}}, with {beta} being an adjustable parameter. Experiments in ac and dc magnetic fields on a sintered cylindrical rod of YBa{sub 2}Cu{sub 3}O{sub 7} yield unambiguous evidence of independent inter- and intragranular contributions to the complex harmonic permeability {tilde {mu}}{sub n} = {mu}{prime}{sub n} -i{mu}{double_prime}{sub n}. Temperature- dependence measurements reveal that, while the intragranular supercurrents disappear at {Tc}{ge}91.2 K, the intergranular supercurrents disappear at T{ge}86.6 K. This result is, to our knowledge, the first clear measurement of the phase-locking temperature of the 3-D matrix formed by YBa{sub 2}Cu{sub 3}O{sub 7} grains, which are in electrical contact with one another through weak links.

  17. Microwave properties of HTS (high temperature superconductor) films

    SciTech Connect (OSTI)

    Cooke, D.W.; Arendt, P.N.; Gray, E.R.; Muenchausen, R.E.; Bennett, B.L.; Foltyn, S.R.; Estler, R.C.; Wu, X.D.; Reeves, G.A.; Elliott, N.E.; Brown, D.R. ); Portis, A.M. ); Taber, R.C. . Labs.); Mogro-Campero, A. . Corporate Research and Development Ce

    1990-01-01

    High-frequency applications of high-temperature superconductors generally fall into two categories: devices that require low values of surface resistance R{sub s} in ambient surface magnetic fields H{sub rf}, and devices that require low R{sub s} in modest fields. Moreover, many applications can be realized with small-surface-area films whereas others require larger areas-radiofrequency (rf) cavities, for example. Regardless of the application, the potential of HTS films is predicated on satisfying one or both of the above-stated requirements. We have measured the surface resistance of small-area (1 cm{sup 2}) and large-area (6.5 cm{sup 2}) YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO) films that have been laser ablated onto LaA{ell}O{sub 3} substrates, large-area (5.1 cm{sup 2}) YBCO films that have been e-beam deposited onto LaA{ell}O{sub 3}, and large-area (11.4 cm{sup 2}) T{ell}-based films that have been magnetron sputtered onto metallic substrates. The best R{sub s} values are obtained from the 1-cm{sup 2} laser-ablated films; they are 40 {mu}{Omega} and 340 {mu}{Omega} at 4 K and 77 K, respectively ({omega}/2{pi} = 10 GHz). Comparable values for Cu are 6 and 13 m{Omega}, respectively. Large-area T{ell}-based films yield typical R{sub s} values of 4 m{Omega} and 14 m{Omega} at 4 K and 77 K, respectively ({omega}/2{pi} = 18 GHz). The dependence of R{sub s} on H{sub rf} for these films indicates that surface fields as large as 55 Oe can be achieved with R{sub s} increasing only by a factor of 10. This field dependence is associated with c-axis texturing.

  18. Method And Apparatus For Evaluatin Of High Temperature Superconductors

    DOE Patents [OSTI]

    Fishman, Ilya M.; Kino, Gordon S.

    1996-11-12

    A technique for evaluation of high-T.sub.c superconducting films and single crystals is based on measurement of temperature dependence of differential optical reflectivity of high-T.sub.c materials. In the claimed method, specific parameters of the superconducting transition such as the critical temperature, anisotropy of the differential optical reflectivity response, and the part of the optical losses related to sample quality are measured. The apparatus for performing this technique includes pump and probe sources, cooling means for sweeping sample temperature across the critical temperature and polarization controller for controlling a state of polarization of a probe light beam.

  19. Single crystal NMR studies of high temperature superconductors

    SciTech Connect (OSTI)

    Pennington, C.H.; Durand, D.J.; Zax, D.B.; Slichter, C.P.; Rice, J.P.; Bukowski, E.D.; Ginsberg, D.M.

    1989-01-01

    The authors report Cu NMR studies in the normal state of a single crystal of the T/sub c/ = 90 K superconductor YBa/sub 2/Cu/sub 3/O/sub 7/minus/delta/. The authors have measured the magnetic shift tensor, the electric field gradient tensor, the nuclear spin-lattice relaxation rate tensor, and the time dependence and functional form of the transverse decay. From these data they obtain information about the charge state and magnetic state of the Cu atoms, and the existence and size of the electronic exchange coupling between spins of adjacent Cu atoms. 18 refs., 3 figs., 2 tabs.

  20. Characterization of high-current, high-temperature superconductor current lead elements

    SciTech Connect (OSTI)

    Niemann, R.C.; Evans, D.J.; Fisher, B.L.; Brockenborough, W.E.; Roberts, P.R.; Rodenbush, A.J.

    1996-08-01

    The refrigeration loads of current leads for superconducting magnets can be significantly reduced by using high-temperature superconductor (HTS) leads. An HTS conductor type that is well suited for this application is a laminated sintered stack of HTS powder-in-tube (PIT) tapes. The superconducting elements are normally characterized by their manufacturer by measuring critical currents at 77 K in self field. Additional characterization, which correlates electrical performance at 77 K and at lower temperatures with applied magnetic fields, provides the current lead designer and conductor element manufacturer with critical information. For HTS conductor elements comprising a laminated and sintered stack of Bi-2223 PIT tapes having an alloyed Ag sheath, this characterization uses variable applied fields and operating temperatures.

  1. New Developments in the Theory of HTSC [High Temperature Superconductors

    DOE R&D Accomplishments [OSTI]

    Abrikosov, A.A.

    1994-09-01

    The superconductor is supposed to consist of alternating layers of two kinds: (1) layers with an attractive electron interaction and an effective mass of usual magnitude, (2) layers without interaction and with a large effective mass. The overlap between the layers is assumed to be small, its energy, t, being much less than {Delta}. It is shown, that such a model explains the most peculiar property found in experiments on electronic Raman light scattering in BSCCO 2212: different threshold values for the Raman satellite measured at two different polarizations of the incident and scattered light. The tunneling conductance G(V)= dJ/dV is analyzed for the same model. In order to fit the qualitative features of experimental data, it is assumed that the tunneling probability to the normal layers is much less, than to the superconducting layers. The conductance is calculated for the case t{much_lt}{Delta}. A brief analysis is given for the case t{approximately}{Delta}, which proves that such an assumption definitely contradicts the experimental data for BSCCO. The possible nature of the electronic states in the normal layers is discussed. In connection with the experimental discovery (angle resolved photoemission spectroscopy, ARPES) of the extended saddle point singularities in the electron spectrum of a variety of HTSC consequences are derived for T{sub c} and {Delta} in a simple model. A large enhancement of superconductivity is possible if the singularity has a sufficient extension and is located close to the Fermi energy. In order to explain the anisotropy of the energy gap, observed in ARPES experiments, on the basis of the "extended saddle point singularities" an assumption is done that the Coulomb interactions are weakly screened, i.e. the Debye screening radius is much larger than the lattice period; this makes the electron interaction long ranged (E-L model).

  2. Process for preparing high-transition-temperature superconductors in the Nb-Al-Ge system

    DOE Patents [OSTI]

    Giorgi, A.L.; Szklarz, E.G.

    1973-01-30

    The patent describes a process for preparing superconducting materials in the Nb-Al-Ge system having transition temperatures in excess of 19K. The process comprises premixing powdered constituents, pressing them into a plug, heating the plug to 1,450-1,800C for 30 minutes to an hour under vacuum or an inert atmosphere, and annealing at moderate temperatures for reasonably long times (approximately 50 hours). High transition-temperature superconductors, including those in the Nb3(Al,Ge) system, prepared in accordance with this process exhibit little degradation in the superconducting transition temperature on being ground to -200 mesh powder. (GRA)

  3. In the OSTI Collections: High-Temperature Superconductors | OSTI, US Dept

    Office of Scientific and Technical Information (OSTI)

    of Energy Office of Scientific and Technical Information High-Temperature Superconductors Technology Basic Science Progress towards theory References Research Organizations and Scientific Societies Reports Available through OSTI's SciTech Connect Patents available through OSTI's DOepatents Additional References One of the lessons of quantum physics is that any set of subatomic particles bound together by mutual attractions have quite distinct states of relative motion determined by how the

  4. Magnetization studies of oxides related to the high temperature cuprate superconductors

    SciTech Connect (OSTI)

    Wang, Z.

    1995-06-19

    The magnetic properties related to the following high temperature superconductors were measured utilizing a Faraday magnetometer: BaCuO{sub 2+x}, La{sub 2} CuO{sub 4}, Sr{sub 2} RhO{sub 4}, Sr{sub 2} VO{sub 4}, and Sr{sub 2} CuO{sub 3}. Neutron diffraction, magnetic susceptibility, and heat capacity measurements are discussed.

  5. Two Phase Transitions Make a High-Temperature Superconductor

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

    does not vanish until a characteristic temperature, T* ("T-star"), is reached. He and Hashimoto et al. have now shown that the pseudogap represents, not a smooth crossover...

  6. High-Tc Superconductor

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

    Donghui Lu, Kyle Shen, and Zhi-Xun Shen Departments of Applied Physics, Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, CA 94305 High-temperature superconductors (HTSC's), following their remarkable discovery in 1986, continue to be at the center stage of modern condensed matter physics. Despite great efforts from both theoretical and experimental sides, the mechanism of HTSC still remains elusive. One of the most peculiar aspects of HTSC's is that their

  7. High transition temperature superconductor/insulator bilayers for the development of ultra-fast electronics

    SciTech Connect (OSTI)

    Sirena, M.; Flix, L. Avils; Instituto Balseiro, Universidad Nacional de Cuyo and CNEA, 8400 Bariloche ; Haberkorn, N.

    2013-07-29

    High transition temperature superconductor (HTc)/SrTiO{sub 3} (STO) bilayers were fabricated by sputtering deposition on (100) STO substrates. Their transport and morphological properties were characterized using conductive atomic force microscopy. The STO barriers present good insulating properties, with long attenuation lengths (? ? 1 nm) which reduce the junction resistance and increase the operating critical current. The samples present roughness values smaller than 1 nm, with an extremely low density of surface defects (?5 10{sup ?5} defects/?m{sup 2}). The high control of the barrier quality over large defect free surfaces is encouraging for the development of microelectronics devices based in HTc Josephson junctions.

  8. Nanoscale interplay of strain and doping in a high-temperature superconductor

    SciTech Connect (OSTI)

    Zeljkovic, Ilija; Gu, Genda; Nieminen, Jouko; Huang, Dennis; Chang, Tay-Rong; He, Yang; Jeng, Horng-Tay; Xu, Zhijun; Wen, Jinsheng; Lin, Hsin; Markiewicz, Robert S.; Bansil, Arun; Hoffman, Jennifer E.

    2014-11-07

    The highest temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable which could be harnessed to enhance the superconducting pairing. Here we report the relationship between local doping and local strain in the cuprate superconductor Bi₂Sr₂CaCu₂O₈₊x. We use scanning tunneling microscopy to discover that the crucial oxygen dopants are periodically distributed, in correlation with local strain. Our picoscale investigation of the intra-unit-cell positions of all oxygen dopants provides essential structural input for a complete microscopic theory.

  9. Nanoscale interplay of strain and doping in a high-temperature superconductor

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

    Zeljkovic, Ilija; Gu, Genda; Nieminen, Jouko; Huang, Dennis; Chang, Tay-Rong; He, Yang; Jeng, Horng-Tay; Xu, Zhijun; Wen, Jinsheng; Lin, Hsin; et al

    2014-11-07

    The highest temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable which could be harnessed to enhance the superconducting pairing. Here we report the relationship between local doping and local strain in the cuprate superconductor Bi₂Sr₂CaCu₂O₈₊x. We use scanning tunneling microscopy to discover that the crucial oxygen dopants are periodically distributed, in correlation with local strain. Our picoscale investigation of the intra-unit-cell positions of all oxygen dopants provides essential structural input for a complete microscopic theory.

  10. Nanoscale interplay of strain and doping in a high-temperature superconductor

    SciTech Connect (OSTI)

    Zeljkovic, Ilija; Gu, Genda; Nieminen, Jouko; Huang, Dennis; Chang, Tay-Rong; He, Yang; Jeng, Horng-Tay; Xu, Zhijun; Wen, Jinsheng; Lin, Hsin; Markiewicz, Robert S.; Bansil, Arun; Hoffman, Jennifer E.

    2014-11-07

    The highest temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable which could be harnessed to enhance the superconducting pairing. Here we report the relationship between local doping and local strain in the cuprate superconductor Bi?Sr?CaCu?O??x. We use scanning tunneling microscopy to discover that the crucial oxygen dopants are periodically distributed, in correlation with local strain. Our picoscale investigation of the intra-unit-cell positions of all oxygen dopants provides essential structural input for a complete microscopic theory.

  11. Resonant Spin Excitation in the High Temperature Superconductor Ba0.6K0.4Fe2As2

    SciTech Connect (OSTI)

    Christianson, Andrew D; Goremychkin, E. A.; Osborn, R.; Rosenkranz, Stephen; Lumsden, Mark D; Malliakas, C.; Todorov, L.; Claus, H.; Chung, D.Y.; Kanatzidis, M.; Bewley, Robert I.; Guidi, T.

    2008-12-18

    A new family of superconductors containing layers of iron arsenide has attracted considerable interest because of their high transition temperatures (T{sub c}), some of which are >50 K, and because of similarities with the high-{sub c} copper oxide superconductors. In both the iron arsenides and the copper oxides, superconductivity arises when an antiferromagnetically ordered phase has been suppressed by chemical doping. A universal feature of the copper oxide superconductors is the existence of a resonant magnetic excitation, localized in both energy and wavevector, within the superconducting phase. This resonance, which has also been observed in several heavy-fermion superconductors is predicted to occur when the sign of the superconducting energy gap takes opposite values on different parts of the Fermi surface, an unusual gap symmetry which implies that the electron pairing interaction is repulsive at short range. Angle-resolved photoelectron spectroscopy shows no evidence of gap anisotropy in the iron arsenides, but such measurements are insensitive to the phase of the gap on separate parts of the Fermi surface. Here we report inelastic neutron scattering observations of a magnetic resonance below T{sub c} in Ba{sub 0.6}K{sub 0.4}Fe{sub 2}As{sub 2}, a phase-sensitive measurement demonstrating that the superconducting energy gap has unconventional symmetry in the iron arsenide superconductors.

  12. Method for preparing high transition temperature Nb/sub 3/Ge superconductors. [Patent application

    DOE Patents [OSTI]

    Newkirk, L.R.; Valencia, F.A.

    1975-06-26

    Bulk coatings of Nb/sub 3/Ge superconductors having transition temperatures in excess of 20/sup 0/K are readily formed by a chemical vapor deposition technique involving the coreduction of NbCl/sub 5/ and GeCl/sub 4/ in the presence of hydrogen. The NbCl/sub 5/ vapor may advantageously be formed quantitatively in the temperature range of about 250 to 260/sup 0/C by the chlorination of Nb metal provided the partial pressure of the product NbCl/sub 5/ vapor is maintained at or below about 0.1 atm.

  13. Method for preparing high transition temperature Nb.sub.3 Ge superconductors

    DOE Patents [OSTI]

    Newkirk, Lawrence R.; Valencia, Flavio A.

    1977-01-01

    Bulk coatings of Nb.sub.3 Ge superconductors having transition temperatures in excess of 20 K are readily formed by a chemical vapor deposition technique involving the coreduction of NbCl.sub.5 and GeCl.sub.4 in the presence of hydrogen. The NbCl.sub.5 vapor may advantageously be formed quantitatively in the temperature range of about 250.degree. to 260.degree. C by the chlorination of Nb metal provided the partial pressure of the product NbCl.sub.5 vapor is maintained at or below about 0.1 atm.

  14. Magnetic frustration in the three-band Anderson lattice model for high-temperature superconductors

    SciTech Connect (OSTI)

    Ihle, D.; Kasner, M. )

    1990-09-01

    The three-band Anderson lattice model for the CuO{sub 2} planes in high-{Tc} superconductors is established. Treating this model by perturbation theory, the effective spin interactions are derived. The antiferromagnetic superexchange integrals are calculated as functions of the direct oxygen transfer and the hole concentration. It is found that frustration in the superexchange occurs, even in the undoped case, which increases with oxygen trnasfer and decreases with hole concentration.

  15. Apex-oxygen-atom tunneling as source of anomalous low-temperature specific heat in high- T sub c superconductors

    SciTech Connect (OSTI)

    Zoli, M. )

    1991-10-01

    A model is proposed in which the quantum tunneling of the apex oxygen atom is coupled to the quasiparticle excitations of the superconducting state. A path-integral formulation allows one to renormalize the coupling constant as a function of temperature. It is shown that such a model can account for the anomalous low-temperature specific heat observed in high-{ital T}{sub {ital c}} YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} superconductors.

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

    SciTech Connect (OSTI)

    Frank Darmann; Robert Lombaerde; Franco Moriconi; Albert Nelson

    2011-10-31

    Zenergy Power has successfully designed, built, tested, and installed in the US electrical grid a saturable reactor Fault Current Limiter. Beginning in 2007, first as SC Power Systems and from 2008 as Zenergy Power, Inc., ZP used DOE matching grant and ARRA funds to help refine the design of the saturated reactor fault current limiter. ZP ultimately perfected the design of the saturated reactor FCL to the point that ZP could reliably design a suitable FCL for most utility applications. Beginning with a very basic FCL design using 1G HTS for a coil housed in a LN2 cryostat for the DC bias magnet, the technology progressed to a commercial system that was offered for sale internationally. Substantial progress was made in two areas. First, the cryogenics cooling system progressed from a sub-cooled liquid nitrogen container housing the HTS coils to cryostats utilizing dry conduction cooling and reaching temperatures down to less than 20 degrees K. Large, round cryostats with “warm bore” diameters of 1.7 meters enabled the design of large tanks to hold the AC components. Second, the design of the AC part of the FCL was refined from a six legged “spider” design to a more compact and lighter design with better fault current limiting capability. Further refinement of the flux path and core shape led to an efficient saturated reactor design requiring less Ampere-turns to saturate the core. In conclusion, the development of the saturable reactor FCL led to a more efficient design not requiring HTS magnets and their associated peripheral equipment, which yielded a more economical product in line with the electric utility industry expectations. The original goal for the DOE funding of the ZP project “Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters” was to stimulate the HTS wire industry with, first 1G, then 2G, HTS wire applications. Over the approximately 5 years of ZP’s product

  17. Method for preparing preferentially oriented, high temperature superconductors using solution reagents

    DOE Patents [OSTI]

    Lee, Dominic F.; Kroeger, Donald M.; Goyal, Amit

    2002-01-01

    A multi-domained bulk REBa.sub.2 CU.sub.3 O.sub.x with low-angle domain boundaries which resemble a quasi-single domained material and a method for producing the same comprising arranging multiple seeds, which can be small single crystals, single domained melt-textured REBa.sub.2 CU.sub.3 O.sub.x pieces, textured substrates comprises of grains with low misorientation angles, or thick film REBa.sub.2 CU.sub.3 O.sub.x deposited on such textured substrate, such seeds being tailored for various REBa.sub.2 CU.sub.3 O.sub.x compounds, in specific pattern and relative seed orientations on a superconductor precursor material which may be placed in contact with a porous substrate so as to reduce the amount of liquid phase in the melt. Because seeds can be arranged in virtually any pattern, high quality REBa.sub.2 CU.sub.3 O.sub.x elements of virtually unlimited size and complex geometry can be fabricated.

  18. Preferentially oriented, High temperature superconductors by seeding and a method for their preparation

    DOE Patents [OSTI]

    Lee, Dominic F.; Kroeger, Donald M.; Goyal, Amit

    2001-01-01

    A multi-domained bulk REBa.sub.2 Cu.sub.3 O.sub.x with low-angle domain boundaries which resembles a quasi-single domained material and a method for producing the same comprising arranging multiple seeds, which can be small single crystals, single domained melt-textured REBa.sub.2 Cu.sub.3 O.sub.x pieces, textured substrates comprised of grains with low misorientation angles, or thick film REBa.sub.2 Cu.sub.3 O.sub.x deposited on such textured substrate, such seeds being tailored for various REBa.sub.2 Cu.sub.3 O.sub.x compounds, in specific pattern and relative seed orientations on a superconductor precursor material which may be placed in contact with a porous substrate so as to reduce the amount of liquid phase in the melt. Because seeds can be arranged in virtually any pattern, high quality REBa.sub.2 Cu.sub.3 O.sub.x elements of virtually unlimited size and complex geometry can be fabricated.

  19. High pressure low temperature studies on 1-2-2 iron-based superconductors using designer diamond cells

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

    Uhoya, Walter O.; Tsoi, Georgiy M.; Vohra, Yogesh K.; Mitchell, Jonathan, E.; Safa-Sefat, Athena; Weir, Samuel

    2013-01-01

    In this study, high pressure low temperature electrical resistance measurements were carried out on a series of 122 iron-based superconductors using a designer diamond anvil cell. These studies were complemented by image plate x-ray diffraction measurements under high pressures and low temperatures at beamline 16-BM-D, HPCAT, Advanced Photon Source. A common feature of the 1-2-2 iron-based materials is the observation of anomalous compressibility effects under pressure and a Tetragonal (T) to Collapsed Tetragonal (CT) phase transition under high pressures. Specific studies on antiferromagnetic spin-density-wave Ba0.5Sr0.5Fe2As2 and Ba(Fe0.9Ru0.1)2As2 samples are presented to 10 K and 41 GPa. The collapsed tetragonal phasemore » was observed at a pressure of 14 GPa in Ba0.5Sr0.5Fe2As2 at ambient temperature. The highest superconducting transition temperature in Ba0.5Sr0.5Fe2As2 was observed to be at 32 K at a pressure of 4.7 GPa. The superconductivity was observed to be suppressed on transformation to the CT phase in 122 materials.« less

  20. Method and apparatus for cooling high temperature superconductors with neon-nitrogen mixtures

    DOE Patents [OSTI]

    Laverman, Royce J.; Lai, Ban-Yen

    1993-01-01

    Apparatus and methods for cooling high temperature superconducting materials (HTSC) to superconductive temperatures within the range of 27.degree. K. to 77.degree. K. using a mixed refrigerant consisting of liquefied neon and nitrogen containing up to about ten mole percent neon by contacting and surrounding the HTSC material with the mixed refrigerant so that free convection or forced flow convection heat transfer can be effected.

  1. Electromagnetic behavior of high-{Tc} superconductors

    SciTech Connect (OSTI)

    Ma, J.G.; Wolff, I.

    1996-05-01

    Using a new proposed model, the electromagnetic behavior of high-temperature superconductors (HTSs) is discussed. It indicates that the real part of the complex conductivity of HTSs is dependent on the driving frequency, and the simulated results agree well with measured data in literature. Nonlinear surface resistances dependence on an external magnetic field are also simulated and compared with experimental results.

  2. Inductively-Charged High-Temperature Superconductors And Methods Of Use

    DOE Patents [OSTI]

    Bromberg, Leslie

    2003-09-16

    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.

  3. Method and apparatus of cryogenic cooling for high temperature superconductor devices

    DOE Patents [OSTI]

    Yuan, Xing; Mine, Susumu

    2005-02-15

    A method and apparatus for providing cryogenic cooling to HTS devices, in particular those that are used in high-voltage electric power applications. The method involves pressurizing liquid cryogen to above one atmospheric pressure to improve its dielectric strength, while sub-cooling the liquid cryogen to below its saturation temperature in order to improve the performance of the HTS components of the device. An apparatus utilizing such a cooling method consists of a vessel that contains a pressurized gaseous cryogen region and a sub-cooled liquid cryogen bath, a liquid cryogen heating coupled with a gaseous cryogen venting scheme to maintain the pressure of the cryogen to a value in a range that corresponds to optimum dielectric strength of the liquid cryogen, and a cooling system that maintains the liquid cryogen at a temperature below its boiling point to improve the performance of HTS materials used in the device.

  4. "Flexible aerogel as a superior thermal insulation for high temperature superconductor cable applications"

    SciTech Connect (OSTI)

    White, Shannon O. [Aspen Aerogel, Inc.; Demko, Jonathan A [ORNL; Tomich, A. [Aspen Aerogel, Inc.

    2010-01-01

    High temperature superconducting (HTS) cables are an advanced technology that can both strengthen and improve the national electrical distribution infrastructure. HTS cables require sufficient cooling to overcome inherent low temperature heat loading. Heat loads are minimized by the use of cryogenic envelopes or cryostats. Cryostats require improvement in efficiency, reliability, and cost reduction to meet the demanding needs of HTS conductors (1G and 2G wires). Aspen Aerogels has developed a compression resistant aerogel thermal insulation package to replace compression sensitive multi-layer insulation (MLI), the incumbent thermal insulation, in flexible cryostats for HTS cables. Oak Ridge National Laboratory tested a prototype aerogel package in a lab-scale pipe apparatus to measure the rate of heat invasion. The lab-scale pipe test results of the aerogel solution will be presented and directly compared to MLI. A compatibility assessment of the aerogel material with HTS system components will also be presented. The aerogel thermal insulation solution presented will meet the demanding needs of HTS cables.

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

    DOE Patents [OSTI]

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

    1994-10-25

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

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

    DOE Patents [OSTI]

    Ginley, David S.; Hietala, Vincent M.; Hohenwarter, Gert K. G.; Martens, Jon S.; Plut, Thomas A.; Tigges, Chris P.; Vawter, Gregory A.; Zipperian, Thomas E.

    1994-10-25

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

  7. High-transition-temperature superconductors in the Nb-Al-Ge system

    DOE Patents [OSTI]

    Giorgi, A.L.; Szklarz, E.G.

    1972-09-26

    The patent describes superconducting materials of the nominal composition Nb(x)Al(y)Ge(l-y), where x is in the range of 1.9 to 2.8 and y is in the range of 0.5 to 0.9, having transition temperatures in the 19 -20K. range which are readily produced by annealing arc-melted compositions, or cold-pressed, heat-treated compositions at moderate temperatures for reasonably long times (about 50 hours).

  8. Highly oxidized superconductors

    DOE Patents [OSTI]

    Morris, D.E.

    1994-09-20

    Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known synthesis in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed. 16 figs.

  9. Highly oxidized superconductors

    DOE Patents [OSTI]

    Morris, Donald E.

    1994-01-01

    Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known syntheses in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed.

  10. Bridging the Gaps of High-Tc Superconductor

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

    Bridging the Gaps of High-Tc Superconductor Since the discovery of high-temperature superconductor by Bednorz and Müller in 1986, this field has become one of the most important research topics in solid state physics. In the past 20 years many unconventional properties have been discovered in this new class of materials. These have challenged our conventional wisdom and driven the development of many novel theories. Among these discoveries, the most mysterious is probably the pseudogap

  11. High-Temperature Superconductivity

    ScienceCinema (OSTI)

    Peter Johnson

    2010-01-08

    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

  12. Ambient-temperature superconductor symetrical metal-dihalide bis-(ethylenedithio)-tetrathiafulvalene compounds

    DOE Patents [OSTI]

    Williams, Jack M.; Wang, Hsien-Hau; Beno, Mark A.

    1987-01-01

    A new class of organic superconductors having the formula (ET).sub.2 MX.sub.2 wherein ET represents bis(ethylenedithio)-tetrathiafulvalene, M is a metal such as Au, Ag, In, Tl, Rb, Pd and the like and X is a halide. The superconductor (ET).sub.2 AuI.sub.2 exhibits a transition temperature of 5 K. which is high for organic superconductors.

  13. Current-carrying element based on second-generation high-temperature superconductor for the magnet system of a fusion neutron source

    SciTech Connect (OSTI)

    Novikov, M. S. Ivanov, D. P. E-mail: denis.ivanov30@mail.ru; Novikov, S. I. Shuvaev, S. A. E-mail: sergey.shuvaev@phystech.edu

    2015-12-15

    Application of current-carrying elements (CCEs) made of second-generation high-temperature superconductor (2G HTS) in magnet systems of a fusion neutron source (FNS) and other fusion devices will allow their magnetic field and thermodynamic stability to be increased substantially in comparison with those of low-temperature superconductor (LTS) magnets. For a toroidal magnet of the FNS, a design of a helical (partially transposed) CCE made of 2G HTS is under development with forced-flow cooling by helium gas, a current of 20–30 kA, an operating temperature of 10–20 K, and a magnetic field on the winding of 12–15 T (prospectively ∼20 T). Short-sized samples of the helical flexible heavy-current CCE are being fabricated and investigated; a pilot-line unit for production of long-sized CCE pieces is under construction. The applied fabrication technique allows the CCE to be produced which combines a high operating current, thermal and mechanical stability, manufacturability, and low losses in the alternating modes. The possibility of fabricating the CCE with the outer dimensions and values of the operating parameter required for the FNS (and with a significant margin) using already available serial 2G HTS tapes is substantiated. The maximum field of toroidal magnets with CCEs made of 2G HTS will be limited only by mechanical properties of the magnet’s casing and structure, while the thermal stability will be approximately two orders of magnitude higher than that of toroidal magnets with LTS-based CCEs. The helical CCE made of 2G HTS is very promising for fusion and hybrid electric power plants, and its design and technologies of production, as well as the prototype coils made of it for the FNS and other tokamaks, are worth developing now.

  14. Electron Correlation in Iron-Based Superconductors

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

    mechanism of superconductivity in the copper-based "high-temperature superconductors." ... for the famous copper-based "high-temperature superconductors," also known as cuprates. ...

  15. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, John R.

    1997-01-01

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

  16. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, J.R.

    1997-02-04

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

  17. Organic Superconductors

    SciTech Connect (OSTI)

    Charles Mielke

    2009-02-27

    Intense magnetic fields are an essential tool for understanding layered superconductors. Fundamental electronic properties of organic superconductors are revealed in intense (60 tesla) magnetic fields. Properties such as the topology of the Fermi surface and the nature of the superconducting order parameter are revealed. With modest maximum critical temperatures~13K the charge transfer salt organic superconductors prove to be incredibly valuable materials as their electronically clean nature and layered (highly anisotropic) structures yield insights to the high temperature superconductors. Observation of de Haas-van Alphen and Shubnikov-de Haas quantum oscillatory phenomena, magnetic field induced superconductivity and re-entrant superconductivity are some of the physical phenomena observed in the charge transfer organic superconductors. In this talk, I will discuss the nature of organic superconductors and give an overview of the generation of intense magnetic fields; from the 60 tesla millisecond duration to the extreme 1000 tesla microsecond pulsed magnetic fields.

  18. Superconductor Requirements and Characterization for High Field Accelerator Magnets

    SciTech Connect (OSTI)

    Barzi, E.; Zlobin, A. V.

    2015-05-01

    The 2014 Particle Physics Project Prioritization Panel (P5) strategic plan for U.S. High Energy Physics (HEP) endorses a continued world leadership role in superconducting magnet technology for future Energy Frontier Programs. This includes 10 to 15 T Nb3Sn accelerator magnets for LHC upgrades and a future 100 TeV scale pp collider, and as ultimate goal that of developing magnet technologies above 20 T based on both High Temperature Superconductors (HTS) and Low Temperature Superconductors (LTS) for accelerator magnets. To achieve these objectives, a sound conductor development and characterization program is needed and is herein described. This program is intended to be conducted in close collaboration with U.S. and International labs, Universities and Industry.

  19. High-resolution dichroic imaging of magnetic flux distributions in superconductors with scanning x-ray microscopy

    SciTech Connect (OSTI)

    Ruoß, S. Stahl, C.; Weigand, M.; Schütz, G.; Albrecht, J.

    2015-01-12

    The penetration of magnetic flux into high-temperature superconductors has been observed using a high-resolution technique based on x-ray magnetic circular dichroism. Superconductors coated with thin soft-magnetic layers are observed in a scanning x-ray microscope under the influence of external magnetic fields. Resulting electric currents in the superconductor create an inhomogeneous magnetic field distribution above the superconductor and lead to a local reorientation of the ferromagnetic layer. Measuring the local magnetization of the ferromagnet by x-ray absorption microscopy with circular-polarized radiation allows the analysis of the magnetic flux distribution in the superconductor with a spatial resolution on the nanoscale.

  20. Bearing design for flywheel energy storage using high-TC superconductors

    DOE Patents [OSTI]

    Hull, John R.; Mulcahy, Thomas M.

    2000-01-01

    A high temperature superconductor material bearing system (38) This system (38) includes a rotor (50) having a ring permanent magnet (60), a plurality of permanent magnets (16, 20 and 70) for interacting to generate levitation forces for the system (38). This group of magnets are a push/pull bearing (75). A high temperature superconductor structure (30) interacts with the ting permanent magnet (60) to provide stabilizing forces for the system (38).

  1. Novel magnets and superconductors studied by high precision magnetic...

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

    Novel magnets and superconductors studied by high precision magnetic susceptometer under pressure An Inductor-capacitor circuit (LC circuit) is a simple, text-book level electric...

  2. Electromagnetics in high-{Tc} superconductors

    SciTech Connect (OSTI)

    Ma, J.G.; Wolff, I.

    1996-04-01

    The behavior of electromagnetic fields in high-{Tc} superconductors (HTS`s) is studied in order to examine their effects in classical electromagnetic boundary value problems. It is shown that an HTS can not be simply treated as a low loss conductor and boundary conditions of HTS`s can not be considered as perfect conducting boundaries like conventional treatments. The electromagnetics of HTS are investigated in terms of complex conductivity, surface impedance with applied magnetic fields, and computational electrodynamics using the new proposed model in Ref. 1.

  3. Dependence of the critical temperature of high-temperature cuprate superconductors on hoppings and spin correlations between CuO{sub 2} planes

    SciTech Connect (OSTI)

    Makarov, I. A., E-mail: macplay@mail.ru; Ovchinnikov, S. G.; Shneider, E. I. [Russian Academy of Sciences, Kirensky Institute of Physics, Siberian Branch (Russian Federation)

    2012-02-15

    The influence of interlayer hoppings on the superconducting transition temperature (T{sub c}) in bilayer cuprates has been studied. The parameter of hopping between layers is expressed as t{sub Up-Tack }(k) = t{sub Up-Tack }(cos(k{sub x}) - cos(k{sub y})){sup 2} and treated as a small perturbation for the states of two CuO{sub 2} planes described by the t-t Prime -t Double-Prime -J* model. In the generalized mean field approximation for d{sub x}{sup 2} - y{sup 2} symmetry of the superconducting gap, neither the interlayer hopping or exchange interaction, nor the pair hopping between CuO{sub 2} layers provides an additional mechanism of Cooper pair formation or an increase in T{sub c}. In the concentration dependence of T{sub c}, the bilayer splitting of the upper Hubbard band of quasi-holes is manifested as two peaks with temperatures slightly lower than the maximum T{sub c} for a single-layer cuprate. Interlayer antiferromagnetic spin correlations suppress bilayer splitting.

  4. Seeing Stripes: Competition and Complexity in High-Temperature...

    Office of Scientific and Technical Information (OSTI)

    Seeing Stripes: Competition and Complexity in High-Temperature Superconductors Citation Details In-Document Search Title: Seeing Stripes: Competition and Complexity in...

  5. Synthesis of highly phase pure BSCCO superconductors

    DOE Patents [OSTI]

    Dorris, Stephen E.; Poeppel, Roger B.; Prorok, Barton C.; Lanagan, Michael T.; Maroni, Victor A.

    1995-01-01

    An article and method of manufacture of (Bi, Pb)-Sr-Ca-Cu-O superconductor. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor.

  6. Synthesis of highly phase pure BSCCO superconductors

    DOE Patents [OSTI]

    Dorris, S.E.; Poeppel, R.B.; Prorok, B.C.; Lanagan, M.T.; Maroni, V.A.

    1995-11-21

    An article and method of manufacture (Bi, Pb)-Sr-Ca-Cu-O superconductor are disclosed. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor. 5 figs.

  7. Bounding the Pseudogap in Cuprate High-TC Superconductors (Technical...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Bounding the Pseudogap in Cuprate High-TC Superconductors Authors: McDonald, Ross David 1 ; Shehter, Arkady 1 ; Balakirev, Fedor F. ...

  8. Melt-spin processing of high {Tc} oxide superconductors

    SciTech Connect (OSTI)

    Folkerts, T.J.; Wu, Hengning; Yoo, S.I.; Merkle, B.D.; Arrasmith, S.R.; Dennis, K.W.; Kramer, M.J.; McCallum, R.W.

    1993-10-01

    Containerless techniques offer distinct advantages for the melt processing of oxide superconductors. The majority of these materials form liquids which are highly reactive with standard crucible materials such as Al{sub 2}O{sub 3} and Pt, resulting in non-negligible contamination. We have developed a containerless melt-spin processing technique where in 50--400 {mu}m particles of REBa{sub 2}Cu{sub 3}O{sub 7-x} high temperature oxide superconductors are melted in free fall through a vertical tube furnace and quenched onto a copper wheel. Previously this method has been successful in producing glasses of NdBa{sub 2}Cu{sub 3}O{sub 7-x} and GdBa{sub 2}Cu{sub 3}O{sub 7-x}. In this report we discuss the results for both stoichiometric and non-stoichiometric YBa{sub 2}Cu{sub 3}O{sub 7-x} (Y123). Thermal, microstructural, and superconducting characterization of both the as-quenched and the annealed materials will be presented.

  9. Strength and flexibility of bulk high-{Tc} superconductors

    SciTech Connect (OSTI)

    Goretta, K.C.; Jiang, M.; Kupperman, D.S.; Lanagan, M.T.; Singh, J.P.; Vasanthamohan, N.; Hinks, D.G.; Mitchell, J.F.; Richardson, J.W. Jr.

    1996-08-01

    Strength, fracture toughness, and elastic modulus data have been gathered for bulk high-temperature superconductors, commercial 99.9% Ag, and a 1.2 at.% Mg/Ag alloy. These data have been used to calculate fracture strains for bulk conductors. The calculations indicate that the superconducting cores of clad tapes should begin to fracture at strains below 0.2%. In addition, residual strains in Ag-clad (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} tapes have been measured by neutron diffraction. An explanation is offered for why many tapes appear to be able to tolerate large strains before exhibiting a reduction in current transport.

  10. Superconductors

    DOE Patents [OSTI]

    Newkirk, Lawrence R.; Valencia, Flavio A.

    1977-02-01

    The structural quality of niobium germanide as a high-transition-temperature superconducting material is substantially improved by the presence of about 5 at. % oxygen. Niobium germanide having this oxygen content may readily be prepared as a bulk coating bonded to a metallic substrate by chemical vapor deposition techniques.

  11. Electronic Structure of LaOFeP - a Different Type of High Temperature

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

    Superconductor Electronic Structure of LaOFeP - a Different Type of High Temperature Superconductor The recent discovery of superconductivity in iron-based layered compounds has created renewed interest in high temperature superconductivity. With a superconducting transition temperature as high as 55 K, this discovery not only ended the monopoly of copper oxides in the family of high temperature superconductors, but also provides a new direction to understand the essential ingredients for

  12. Enhanced Superconducting Gaps in Trilayer High-Temperature Bi...

    Office of Scientific and Technical Information (OSTI)

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

  13. Neutron scattering studies of spin-phonon hybridization and superconducting spin gaps in the high temperature superconductor La2-x(Sr;Ba)xCuO4

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

    Wagman, J. J.; Carlo, Jeremy P.; Gaudet, J.; Van Gastel, G. J.; Abernathy, Douglas L.; Stone, Matthew B.; Granroth, Garrett E.; Kolesnikov, Alexander I.; Savici, Andrei T.; Kim, Young -June; et al

    2016-03-14

    We present time-of-flight neutron-scattering measurements on single crystals of La2-xBaxCuO4 (LBCO) with 0 ≤ x ≤ 0.095 and La2-xSrxCuO4 (LSCO) with x = 0.08 and 0.11. This range of dopings spans much of the phase diagram relevant to high temperature cuprate superconductivity, ranging from insulating, three dimensional commensurate long range antiferromagnetic order for x ≤ 0.02 to two dimensional (2D) incommensurate antiferromagnetism co-existing with superconductivity for x ≥ 0.05. Previous work on lightly doped LBCO with x = 0.035 showed a clear resonant enhancement of the inelastic scattering coincident with the low energy crossings of the highly dispersive spin excitationsmore » and quasi-2D optic phonons. The present work extends these measurements across the phase diagram and shows this enhancement to be a common feature to this family of layered quantum magnets. Furthermore we show that the low temperature, low energy magnetic spectral weight is substantially larger for samples with non-superconducting ground states relative to any of the samples with superconducting ground states. Lastly spin gaps, suppression of low energy magnetic spectral weight, are observed in both superconducting LBCO and LSCO samples, consistent with previous observations for superconducting LSCO« less

  14. Crystal Growth And Characterization of the Model High-Temperature Superconductor HgBa{sub 2}CuO{sub 4+{delta}}

    SciTech Connect (OSTI)

    Zhao, Xudong; Yu, Guichuan; Cho, Yong-Chan; Chabot-Couture, Guillaume; Barisic, Neven; Bourges, Philippe; Kaneko, Nobuhisa; Li, Yuan; Lu, Li; Motoyama, Eugene M.; Vajk, Owen P.; Greven, Martin; /Stanford U., Appl. Phys. Dept. /SLAC, SSRL /Jilin U. /Stanford U., Phys. Dept. /Saclay /NIST, Wash., D.C.

    2007-03-16

    Since the discovery of high-transition-temperature (T{sub c}) superconductivity in La{sub 2-x}Ba{sub x}CuO{sub 4} in 1986, the study of the lamellar copper oxides has remained at the forefront of condensed matter physics. Apart from their unusually high values of T{sub c}, these materials also exhibit a variety of complex phenomena and phases. This rich behavior is a consequence of the lamellar crystal structures, formed of copper-oxygen sheets separated by charge reservoir layers, and of the strong electron-electron correlations in the copper-oxygen sheets. After two decades of intensive research, which has stimulated many valuable new insights into correlated electron systems in general, there remains a lack of consensus regarding the correct theory for high-T{sub c} superconductivity. The ultimate technological goal of room-temperature superconductivity might only be attained after the development of a deeper understanding of the mercury-based compounds HgBa{sub 2}Ca{sub n-1}Cu{sub n}OI{sub 2n+2+{delta}}, which currently exhibit the highest T{sub c}values. One very important issue in this regard is the role of electronic versus chemical and structural inhomogeneities in these materials, and the associated need to separate material-specific properties from those that are essential to superconductivity. Unfortunately, there has been remarkably little scientific work on the mercury-based compounds because sizable crystals have not been available; quantitative measurements of any kind would be invaluable benchmarks for testing the theories of high-T{sub c} superconductivity. The compounds HgBa{sub 2}Ca{sub n-1}Cu{sub n}OI{sub 2n+2+{delta}} can be viewed as model systems not only because of their record high-T{sub c} values, but also because of their high-symmetry crystal structures. Of particular interest is the simplest member of this materials family, HgBa{sub 2}CuO{sub 4+{delta}} (Hg1201), which possesses only one copper-oxygen sheet per unit cell (n = 1), as

  15. High Temperature Superconductors: From Delivery to Applications (Presentation from 2011 Ernest Orlando Lawrence Award-winner, Dr. Amit Goyal, and including introduction by Energy Secretary, Dr. Steven Chu)

    ScienceCinema (OSTI)

    Goyal, Amit (Oak Ridge National Laboratory)

    2012-06-28

    Dr. Amit Goyal, a high temperature superconductivity (HTS) researcher at Oak Ridge National Laboratory, was named a 2011 winner of the Department of Energy's Ernest Orlando Lawrence Award honoring U.S. scientists and engineers for exceptional contributions in research and development supporting DOE and its mission. Winner of the award in the inaugural category of Energy Science and Innovation, Dr. Goyal was cited for his work in 'pioneering research and transformative contributions to the field of applied high temperature superconductivity, including fundamental materials science advances and technical innovations enabling large-scale applications of these novel materials.' Following his basic research in grain-to-grain supercurrent transport, Dr. Goyal focused his energy in transitioning this fundamental understanding into cutting-edge technologies. Under OE sponsorship, Dr. Goyal co-invented the Rolling Assisted Bi-Axially Textured Substrate technology (RABiTS) that is used as a substrate for second generation HTS wires. OE support also led to the invention of Structural Single Crystal Faceted Fiber Substrate (SSIFFS) and the 3-D Self Assembly of Nanodot Columns. These inventions and associated R&D resulted in 7 R&D 100 Awards including the 2010 R&D Magazine's Innovator of the Year Award, 3 Federal Laboratory Consortium Excellence in Technology Transfer National Awards, a DOE Energy100 Award and many others. As a world authority on HTS materials, Dr. Goyal has presented OE-sponsored results in more than 150 invited talks, co-authored more than 350 papers and is a fellow of 7 professional societies.

  16. Response of High-Tc Superconductor Metamaterials to High Intensity THz

    Office of Scientific and Technical Information (OSTI)

    Radiation (Conference) | SciTech Connect Response of High-Tc Superconductor Metamaterials to High Intensity THz Radiation Citation Details In-Document Search Title: Response of High-Tc Superconductor Metamaterials to High Intensity THz Radiation Authors: Grady, Nathaniel [1] ; Perkins Jr., Bradford G. [2] ; Hwang, Harold Y. [2] ; Brandt, Nate [2] ; Torchinsky, Darius [2] ; Singh, Ranjan [1] ; Yan, Li [3] ; Jia, Quanxi [1] ; Trugman, Stuart A. [1] ; Taylor, Antoinette J. [1] ; Nelson, Keith

  17. High temperature interfacial superconductivity

    DOE Patents [OSTI]

    Bozovic, Ivan; Logvenov, Gennady; Gozar, Adrian Mihai

    2012-06-19

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

  18. Low-field diamagnetic response of granular superconductors at finite temperatures

    SciTech Connect (OSTI)

    Auletta, C.; Raiconi, G. ); De Luca, R.; Pace, S. )

    1994-05-01

    We study the low-field diamagnetic response of granular superconductors at finite temperatures by means of a simple two-dimensional Josephson-junction array. The temperature effects are taken into account by inserting white-noise current sources in parallel to the resistively shunted junction circuit models of the Josephson junctions of the network. By this analysis we argue that a simplified one-dimensional description of the equivalent circuit, proposed by the authors for cylindrical granular superconductors, is still valid even in the presence of thermally activated flux jumps. A flux-creep picture for intergranular flux motion follows.

  19. Ambient-pressure organic superconductor

    DOE Patents [OSTI]

    Williams, Jack M.; Wang, Hsien-Hau; Beno, Mark A.

    1986-01-01

    A new class of organic superconductors having the formula (ET).sub.2 MX.sub.2 wherein ET represents bis(ethylenedithio)-tetrathiafulvalene, M is a metal such as Au, Ag, In, Tl, Rb, Pd and the like and X is a halide. The superconductor (ET).sub.2 AuI.sub.2 exhibits a transition temperature of 5 K which is high for organic superconductors.

  20. Method for preparing high temperature superconductor

    DOE Patents [OSTI]

    Balachandran, Uthamalingam (Hinsdale, IL); Chudzik, Michael P. (Beacon, NY)

    2002-01-01

    A method of depositing a biaxially textured metal oxide on a substrate defining a plane in which metal oxide atoms are vaporized from a source to form a plume of metal oxide atoms. Atoms in the plume disposed at a selected angle in a predetermined range of angles to the plane of the substrate are allowed to contact the substrate while preventing atoms outside a selected angle from reaching the substrate. The preferred range of angles is 40.degree.-70.degree. and the preferred angle is 60.degree..+-.5.degree.. A moving substrate is disclosed.

  1. Dense high temperature ceramic oxide superconductors

    DOE Patents [OSTI]

    Landingham, R.L.

    1993-10-12

    Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

  2. Dense high temperature ceramic oxide superconductors

    DOE Patents [OSTI]

    Landingham, Richard L.

    1993-01-01

    Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

  3. Enhanced Superconducting Gaps in Trilayer High-Temperature Bi (2) Sr (2) Ca

    Office of Scientific and Technical Information (OSTI)

    (2) Cu (3) O (10+delta) Cuprate Superconductor (Journal Article) | SciTech Connect Enhanced Superconducting Gaps in Trilayer High-Temperature Bi (2) Sr (2) Ca (2) Cu (3) O (10+delta) Cuprate Superconductor Citation Details In-Document Search Title: Enhanced Superconducting Gaps in Trilayer High-Temperature Bi (2) Sr (2) Ca (2) Cu (3) O (10+delta) Cuprate Superconductor Authors: Ideta, S ; Takashima, K. ; Hashimoto, M. ; Yoshida, T. ; Fujimori, A. ; Anzai, H. ; Fujita, T. ; Nakashima, Y. ;

  4. Surface texturing of superconductors by controlled oxygen pressure

    DOE Patents [OSTI]

    Chen, N.; Goretta, K.C.; Dorris, S.E.

    1999-01-05

    A method of manufacture of a textured layer of a high temperature superconductor on a substrate is disclosed. The method involves providing an untextured high temperature superconductor material having a characteristic ambient pressure peritectic melting point, heating the superconductor to a temperature below the peritectic temperature, establishing a reduced pO{sub 2} atmosphere below ambient pressure causing reduction of the peritectic melting point to a reduced temperature which causes melting from an exposed surface of the superconductor and raising pressure of the reduced pO{sub 2} atmosphere to cause solidification of the molten superconductor in a textured surface layer. 8 figs.

  5. Surface texturing of superconductors by controlled oxygen pressure

    DOE Patents [OSTI]

    Chen, Nan; Goretta, Kenneth C.; Dorris, Stephen E.

    1999-01-01

    A method of manufacture of a textured layer of a high temperature superconductor on a substrate. The method involves providing an untextured high temperature superconductor material having a characteristic ambient pressure peritectic melting point, heating the superconductor to a temperature below the peritectic temperature, establishing a reduced pO.sub.2 atmosphere below ambient pressure causing reduction of the peritectic melting point to a reduced temperature which causes melting from an exposed surface of the superconductor and raising pressure of the reduced pO.sub.2 atmosphere to cause solidification of the molten superconductor in a textured surface layer.

  6. Giant flux creep through the surface barriers and the irreversibility line in high-{Tc} superconductors

    SciTech Connect (OSTI)

    Burlachkov, L.; Geshkenbein, V.B. ||; Koshelev, A.E. |; Larkin, A.I. |; Vinokur, V.M.

    1994-05-01

    Magnetic flux relaxation over the surface barrier in high temperature superconductors are investigated Vortex dynamics controlled by the penetration both of pancake vortices and vortex lines are discussed. The penetration field H{sub p} for pancakes decay is exponentially with temperature. The size of the magnetization loop is determined by the decay of H{sub p} during the process of relaxation, but its shape remains unchanged. The irreversibility line associated with the pancake penetration is given by H{sub irr} {proportional_to} exp(- 2T/T{sub o}), and may lie both above and below the melting line.

  7. Universal Charge Order in the High-Tc Superconductors | Stanford

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

    Synchrotron Radiation Lightsource Universal Charge Order in the High-Tc Superconductors Wednesday, May 4, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Eduardo H. da Silva Neto - UBC Eduardo H. da Silva Neto was born in Recife, Brazil. He obtained his B.A. in Physics and Mathematics (2008) from Amherst College, and his Ph. D. (2013) in Physics from Princeton University. Since 2013 he has been a Max-Planck-UBC postdoctoral research fellow at the Quantum Matter Institute at

  8. High field superconductor development and understanding project, Final Report

    SciTech Connect (OSTI)

    Larbalestier, David C.; Lee, Peter J.

    2009-07-15

    Over 25 years the Applied Superconductivity Center at the University of Wisconsin-Madison provided a vital technical resource to the High Energy Physics community covering development in superconducting strand for HEP accelerator magnet development. In particular the work of the group has been to develop the next generation of high field superconductors for high field application. Grad students Mike Naus, Chad Fischer, Arno Godeke and Matt Jewell improved our understanding of the microstructure and microchemistry of Nb3Sn and their impact on the physical and mechanical properties. The success of this work has led to the continued funding of this work at the ASC after it moved to the NHMFL and also to direct funding from BNL for some aspects of Nb3Sn cable evaluation.

  9. Universal Charge Order in the High-Tc Superconductors | Stanford...

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

    such as heavy-fermion materials and copper-oxide based superconductors, by the use ... (BCS) theory of superconductivity are obtained in some copper-oxide (cuprate) materials. ...

  10. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  11. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  12. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  13. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  14. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  15. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  16. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Print In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One

  17. Engineered flux-pinning centers in BSCCO TBCCO and YBCO superconductors

    DOE Patents [OSTI]

    Goretta, Kenneth C.; Lanagan, Michael T.; Miller, Dean J.; Sengupta, Suvankar; Parker, John C.; Hu, Jieguang; Balachandran, Uthamalingam; Siegel, Richard W.; Shi, Donglu

    1999-01-01

    A method of preparing a high temperature superconductor. A method of preparing a superconductor includes providing a powdered high temperature superconductor and a nanophase material. These components are combined to form a solid compacted mass with the material disposed in the polycrystalline high temperature superconductor. This combined mixture is rapidly heated, forming a dispersion of nanophase size particles without a eutectic reaction. These nanophase particles can have a flat plate or columnar type morphology.

  18. Engineered flux-pinning centers in BSCCO TBCCO and YBCO superconductors

    DOE Patents [OSTI]

    Goretta, K.C.; Lanagan, M.T.; Miller, D.J.; Sengupta, S.; Parker, J.C.; Hu, J.; Balachandran, U.; Siegel, R.W.; Shi, D.

    1999-07-27

    A method of preparing a high temperature superconductor is disclosed. A method of preparing a superconductor includes providing a powdered high temperature superconductor and a nanophase material. These components are combined to form a solid compacted mass with the material disposed in the polycrystalline high temperature superconductor. This combined mixture is rapidly heated, forming a dispersion of nanophase size particles without a eutectic reaction. These nanophase particles can have a flat plate or columnar type morphology. 4 figs.

  19. Evidence for a new excitation at the interface between a high-Tc superconductor and a topological insulator

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

    Zareapour, Parisa; Hayat, Alex; Zhao, Shu Yang F.; Kreshchuk, Michael; Lee, Yong Kiat; Reijnders, Anjan A.; Jain, Achint; Xu, Zhijun; Liu, T. S.; Gu, G. D.; et al

    2014-12-09

    In this research, high-temperature superconductors exhibit a wide variety of novel excitations. If contacted with a topological insulator, the lifting of spin rotation symmetry in the surface states can lead to the emergence of unconventional superconductivity and novel particles. In pursuit of this possibility, we fabricated high critical-temperature (Tc ~ 85 K) superconductor/topological insulator (Bi₂Sr₂CaCu₂O₈₊δ/Bi₂Te₂Se) junctions. Below 75 K, a zero-bias conductance peak (ZBCP) emerges in the differential conductance spectra of this junction. The magnitude of the ZBCP is suppressed at the same rate for magnetic fields applied parallel or perpendicular to the junction. Furthermore, it can still be observedmore » and does not split up to at least 8.5 T. The temperature and magnetic field dependence of the excitation we observe appears to fall outside the known paradigms for a ZBCP.« less

  20. Phonon characteristics of high {Tc} superconductors from neutron Doppler broadening measurements

    SciTech Connect (OSTI)

    Trela, W.J.; Kwei, G.H.; Lynn, J.E.; Meggers, K.

    1994-12-01

    Statistical information on the phonon frequency spectrum of materials can be measured by neutron transmission techniques if they contain nuclei with low energy resonances, narrow enough to be Doppler-broadened, in their neutron cross sections. The authors have carried out some measurements using this technique for materials of the lanthanum barium cuprate class, La{sub 2{minus}x}Ba{sub x}CuO{sub 4}. Two samples with slightly different concentrations of oxygen, one being superconductive, the other not, were examined. Pure lanthanum cuprate was also measured. Lanthanum, barium and copper all have relatively low energy narrow resonances. Thus it should be possible to detect differences in the phonons carried by different kinds of atom in the lattice. Neutron cross section measurements have been made with high energy resolution and statistical precision on the 59m flight path of LANSCE, the pulsed spallation neutron source at Los Alamos National Laboratory. Measurements on all three materials were made over a range of temperatures from 15K to 300K, with small steps through the critical temperature region near 27K. No significant changes in the mean phonon energy of the lanthanum atoms were observed near the critical temperature of the super-conducting material. It appears however that the mean phonon energy of lanthanum in the superconductor is considerably higher than that in the non-superconductors. The samples used in this series of experiments were too thin in barium and copper to determine anything significant about their phonon spectra.

  1. High-temperature superconducting current leads

    SciTech Connect (OSTI)

    Niemann, R.C.

    1995-03-01

    Use of high-temperature superconductors (HTSs) for current leads to deliver power to devices at liquid helium temperature can reduce refrigeration requirements to values significantly below those achievable with conventional leads. HTS leads are now near commercial realization. Argonne National Laboratory (ANL) has developed a sinter-forge process to fabricate current leads from bismuth-based superconductors. The current-carrying capacity of these leads is five times better than that of HTS leads made by a conventional fabrication process. ANL along with Superconductivity, Inc., has developed a 1500 ampere current lead for an existing superconducting magnetic energy storage (SMES) device. With Babcock & Wilcox Company, Argonne is creating 16-kiloampere leads for use in a 0.5 MWh SMES. In a third project Argonne performed characterization testing of a existing, proprietary conduction-cooled lead being developed by Zer Res Corp.

  2. Probing high-energy spin fluctuations in iron pnictide superconductors...

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

    spin fluctuations in iron pnictide superconductors and the metal-insulator transition in rare-earth nickelates by soft X-ray RIXS Wednesday, November 18, 2015 - 3:00pm...

  3. High critical currents in heavily doped (Gd,Y)Ba2Cu3Ox superconductor tapes

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

    Selvamanickam, V.; Gharahcheshmeh, M. Heydari; Xu, A.; Galstyan, E.; Delgado, L.; Cantoni, C.

    2015-01-20

    REBa2Cu3Ox superconductor tapes with moderate levels of dopants have been optimized for high critical current density in low magnetic fields at 77 K, but they do not exhibit exemplary performance in conditions of interest for practical applications, i.e., temperatures less than 50 K and fields of 2–30 T. Heavy doping of REBCO tapes has been avoided by researchers thus far due to deterioration in properties. Here, we report achievement of critical current densities (Jc) above 20 MA/cm2 at 30 K, 3 T in heavily doped (25 mol. % Zr-added) (Gd,Y)Ba2Cu3Ox superconductor tapes, which is more than three times higher thanmore » the Jc typically obtained in moderately doped tapes. Pinning force levels above 1000 GN/m3 have also been attained at 20 K. A composition map of lift factor in Jc (ratio of Jc at 30 K, 3 T to the Jc at 77 K, 0 T) has been developed which reveals the optimum film composition to obtain lift factors above six, which is thrice the typical value. A highly c-axis aligned BaZrO3 (BZO) nanocolumn defect density of nearly 7 × 1011 cm–2 as well as 2–3nm sized particles rich in Cu and Zr have been found in the high Jc films.« less

  4. High-efficiency solid-state lighting and superconductor research receives

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

    funding High-efficiency solid-state lighting and superconductor High-efficiency solid-state lighting and superconductor research receives funding Each project will be funded for up to three years. August 28, 2009 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National

  5. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor 3D Charge Order Found in Superconductor Print Wednesday, 08 June 2016 00:00 Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction

  6. High temperature interface superconductivity

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

    Gozar, A.; Bozovic, I.

    2016-01-20

    High-Tc superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-Tc Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both ‘passive’ hetero-structures as well as surface-induced effects by external gating are discussed. Here, wemore » conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.« less

  7. High temperature furnace

    DOE Patents [OSTI]

    Borkowski, Casimer J.

    1976-08-03

    A high temperature furnace for use above 2000.degree.C is provided that features fast initial heating and low power consumption at the operating temperature. The cathode is initially heated by joule heating followed by electron emission heating at the operating temperature. The cathode is designed for routine large temperature excursions without being subjected to high thermal stresses. A further characteristic of the device is the elimination of any ceramic components from the high temperature zone of the furnace.

  8. High temperature sensor

    DOE Patents [OSTI]

    Tokarz, Richard D.

    1982-01-01

    A high temperature sensor includes a pair of electrical conductors separated by a mass of electrical insulating material. The insulating material has a measurable resistivity within the sensor that changes in relation to the temperature of the insulating material within a high temperature range (1,000 to 2,000 K.). When required, the sensor can be encased within a ceramic protective coating.

  9. Generation of charge imbalance in a superconductor by a temperature gradient

    SciTech Connect (OSTI)

    Entin-Wohlman, O.; Orbach, R.

    1980-11-01

    The charge-imbalance voltage in a superconductor carrying a current in the presence of a temperature gradient is calculated from the Boltzmann equation in the clean limit. We demonstrate why the Green's-function approach in the dirty limit, first performed by Schmid and Schoem, generates the same Boltzmann-like equation for the distribution function. In addition, the charge-imbalance voltage in the absence of an impressed current is calculated. It is shown to depend on del/sup 2/T+(delT)/sup 2//T, and not solely on (delT)/sup 2/. The calculations are limited to the temperature regime near T/sub c/, such that ..delta..<

  10. Electron Correlation in Iron-Based Superconductors

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

    of the deepest mysteries in modern physics-the mechanism of superconductivity in the copper-based "high-temperature superconductors." One clue lies in whether the electrons in...

  11. High temperature refrigerator

    DOE Patents [OSTI]

    Steyert, Jr., William A.

    1978-01-01

    A high temperature magnetic refrigerator which uses a Stirling-like cycle in which rotating magnetic working material is heated in zero field and adiabatically magnetized, cooled in high field, then adiabatically demagnetized. During this cycle said working material is in heat exchange with a pumped fluid which absorbs heat from a low temperature heat source and deposits heat in a high temperature reservoir. The magnetic refrigeration cycle operates at an efficiency 70% of Carnot.

  12. (Neutron scattering studies of the high-temperature superconducting materials)

    SciTech Connect (OSTI)

    Mook, H.A. Jr.

    1991-01-04

    The traveler was given beam time at the ILL to continue neutron scattering work on high-temperature superconductivity. The unique facilities at the ILL for both high-energy and low-energy neutron instrumentation made the experiments possible. The measurements consisted of two basic types. The first of these is the study of the nature of spin fluctuations in high-{Tc} materials. This work is fundamental to the mechanism that is responsible for the high-transition temperatures. The second consisted of experiments on the flux lattice in high-temperature superconductors. The flux lattice has interesting physics in its own right and is important in understanding the current-carrying capability of superconductors.

  13. High temperature measuring device

    DOE Patents [OSTI]

    Tokarz, Richard D.

    1983-01-01

    A temperature measuring device for very high design temperatures (to 2,000.degree. C.). The device comprises a homogenous base structure preferably in the form of a sphere or cylinder. The base structure contains a large number of individual walled cells. The base structure has a decreasing coefficient of elasticity within the temperature range being monitored. A predetermined quantity of inert gas is confined within each cell. The cells are dimensionally stable at the normal working temperature of the device. Increases in gaseous pressure within the cells will permanently deform the cell walls at temperatures within the high temperature range to be measured. Such deformation can be correlated to temperature by calibrating similarly constructed devices under known time and temperature conditions.

  14. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, R.G.

    1998-05-05

    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.

  15. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, Robert G.

    1998-01-01

    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.

  16. High-temperature sensor

    DOE Patents [OSTI]

    Not Available

    1981-01-29

    A high temperature sensor is described which includes a pair of electrical conductors separated by a mass of electrical insulating material. The insulating material has a measurable resistivity within the sensor that changes in relation to the temperature of the insulating material within a high temperature range (1000 to 2000/sup 0/K). When required, the sensor can be encased within a ceramic protective coating.

  17. Evidence for a new excitation at the interface between a high-Tc superconductor and a topological insulator

    SciTech Connect (OSTI)

    Zareapour, Parisa; Xu, Zhijun; Hayat, Alex; Zhao, Shu Yang F.; Kreshchuk, Michael; Lee, Yong Kiat; Reijnders, Anjan A.; Jain, Achint; Liu, T. S.; Gu, G. D.; Jia, Shuang; Cava, Robert J.; Burch, Kenneth S.

    2014-12-09

    High-temperature superconductors exhibit a wide variety of novel excitations. If contacted with a topological insulator, the lifting of spin rotation symmetry in the surface states can lead to the emergence of unconventional superconductivity and novel particles. In pursuit of this possibility, we fabricated high critical-temperature (Tc ~ 85 K) superconductor/topological insulator (Bi?Sr?CaCu?O???/Bi?Te?Se) junctions. Below 75 K, a zero-bias conductance peak (ZBCP) emerges in the differential conductance spectra of this junction. The magnitude of the ZBCP is suppressed at the same rate for magnetic fields applied parallel or perpendicular to the junction. Furthermore, it can still be observed and does not split up to at least 8.5 T. The temperature and magnetic field dependence of the excitation we observe appears to fall outside the known paradigms for a ZBCP.

  18. Evidence for a new excitation at the interface between a high-Tc superconductor and a topological insulator

    SciTech Connect (OSTI)

    Zareapour, Parisa; Hayat, Alex; Zhao, Shu Yang F.; Kreshchuk, Michael; Lee, Yong Kiat; Reijnders, Anjan A.; Jain, Achint; Xu, Zhijun; Liu, T. S.; Gu, G. D.; Jia, Shuang; Cava, Robert J.; Burch, Kenneth S.

    2014-12-09

    In this research, high-temperature superconductors exhibit a wide variety of novel excitations. If contacted with a topological insulator, the lifting of spin rotation symmetry in the surface states can lead to the emergence of unconventional superconductivity and novel particles. In pursuit of this possibility, we fabricated high critical-temperature (Tc ~ 85 K) superconductor/topological insulator (Bi?Sr?CaCu?O???/Bi?Te?Se) junctions. Below 75 K, a zero-bias conductance peak (ZBCP) emerges in the differential conductance spectra of this junction. The magnitude of the ZBCP is suppressed at the same rate for magnetic fields applied parallel or perpendicular to the junction. Furthermore, it can still be observed and does not split up to at least 8.5 T. The temperature and magnetic field dependence of the excitation we observe appears to fall outside the known paradigms for a ZBCP.

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

    SciTech Connect (OSTI)

    Kim, Hyunsoo

    2013-05-15

    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.

  20. High temperature pressure gauge

    DOE Patents [OSTI]

    Echtler, J. Paul; Scandrol, Roy O.

    1981-01-01

    A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.

  1. Superconductor cable

    DOE Patents [OSTI]

    Allais, Arnaud; Schmidt, Frank; Marzahn, Erik

    2010-05-04

    A superconductor cable is described, having a superconductive flexible cable core (1) , which is laid in a cryostat (2, 3, 4), in which the cable core (1) runs in the cryostat (2, 3, 4) in the form of a wave or helix at room temperature.

  2. High Temperature ESP Monitoring

    SciTech Connect (OSTI)

    Jack Booker; Brindesh Dhruva

    2011-06-20

    The objective of the High Temperature ESP Monitoring project was to develop a downhole monitoring system to be used in wells with bottom hole well temperatures up to 300C for measuring motor temperature, formation pressure, and formation temperature. These measurements are used to monitor the health of the ESP motor, to track the downhole operating conditions, and to optimize the pump operation. A 220 C based High Temperature ESP Monitoring system was commercially released for sale with Schlumberger ESP motors April of 2011 and a 250 C system with will be commercially released at the end of Q2 2011. The measurement system is now fully qualified, except for the sensor, at 300 C.

  3. High temperature probe

    DOE Patents [OSTI]

    Swan, Raymond A.

    1994-01-01

    A high temperature probe for sampling, for example, smokestack fumes, and is able to withstand temperatures of 3000.degree. F. The probe is constructed so as to prevent leakage via the seal by placing the seal inside the water jacket whereby the seal is not exposed to high temperature, which destroys the seal. The sample inlet of the probe is also provided with cooling fins about the area of the seal to provide additional cooling to prevent the seal from being destroyed. Also, a heated jacket is provided for maintaining the temperature of the gas being tested as it passes through the probe. The probe includes pressure sensing means for determining the flow velocity of an efficient being sampled. In addition, thermocouples are located in various places on the probe to monitor the temperature of the gas passing there through.

  4. Method and apparatus for measuring gravitational acceleration utilizing a high temperature superconducting bearing

    DOE Patents [OSTI]

    Hull, John R.

    2000-01-01

    Gravitational acceleration is measured in all spatial dimensions with improved sensitivity by utilizing a high temperature superconducting (HTS) gravimeter. The HTS gravimeter is comprised of a permanent magnet suspended in a spaced relationship from a high temperature superconductor, and a cantilever having a mass at its free end is connected to the permanent magnet at its fixed end. The permanent magnet and superconductor combine to form a bearing platform with extremely low frictional losses, and the rotational displacement of the mass is measured to determine gravitational acceleration. Employing a high temperature superconductor component has the significant advantage of having an operating temperature at or below 77K, whereby cooling may be accomplished with liquid nitrogen.

  5. HIGH TEMPERATURE THERMOCOUPLE

    DOE Patents [OSTI]

    Eshayu, A.M.

    1963-02-12

    This invention contemplates a high temperature thermocouple for use in an inert or a reducing atmosphere. The thermocouple limbs are made of rhenium and graphite and these limbs are connected at their hot ends in compressed removable contact. The rhenium and graphite are of high purity and are substantially stable and free from diffusion into each other even without shielding. Also, the graphite may be thick enough to support the thermocouple in a gas stream. (AEC)

  6. High temperature thermometric phosphors

    DOE Patents [OSTI]

    Allison, Stephen W.; Cates, Michael R.; Boatner, Lynn A.; Gillies, George T.

    1999-03-23

    A high temperature phosphor consists essentially of a material having the general formula LuPO.sub.4 :Dy.sub.(x),Eu.sub.y) wherein: 0.1 wt %.ltoreq.x.ltoreq.20 wt % and 0.1 wt %.ltoreq.y.ltoreq.20 wt %. The high temperature phosphor is in contact with an article whose temperature is to be determined. The article having the phosphor in contact with it is placed in the environment for which the temperature of the article is to be determined. The phosphor is excited by a laser causing the phosphor to fluoresce. The emission from the phosphor is optically focused into a beam-splitting mirror which separates the emission into two separate emissions, the emission caused by the dysprosium dopant and the emission caused by the europium dopent. The separated emissions are optically filtered and the intensities of the emission are detected and measured. The ratio of the intensity of each emission is determined and the temperature of the article is calculated from the ratio of the intensities of the separate emissions.

  7. High temperature thermometric phosphors

    DOE Patents [OSTI]

    Allison, S.W.; Cates, M.R.; Boatner, L.A.; Gillies, G.T.

    1999-03-23

    A high temperature phosphor consists essentially of a material having the general formula LuPO{sub 4}:Dy{sub x},Eu{sub y} wherein: 0.1 wt % {<=} x {<=} 20 wt % and 0.1 wt % {<=} y {<=} 20 wt %. The high temperature phosphor is in contact with an article whose temperature is to be determined. The article having the phosphor in contact with it is placed in the environment for which the temperature of the article is to be determined. The phosphor is excited by a laser causing the phosphor to fluoresce. The emission from the phosphor is optically focused into a beam-splitting mirror which separates the emission into two separate emissions, the emission caused by the dysprosium dopant and the emission caused by the europium dopant. The separated emissions are optically filtered and the intensities of the emission are detected and measured. The ratio of the intensity of each emission is determined and the temperature of the article is calculated from the ratio of the intensities of the separate emissions. 2 figs.

  8. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor Print Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction (RSXD), a technique sensitive to both structure and electronic state at

  9. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor Print Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction (RSXD), a technique sensitive to both structure and electronic state at

  10. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor Print Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction (RSXD), a technique sensitive to both structure and electronic state at

  11. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor Print Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction (RSXD), a technique sensitive to both structure and electronic state at

  12. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor Print Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction (RSXD), a technique sensitive to both structure and electronic state at

  13. 3D Charge Order Found in Superconductor

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

    3D Charge Order Found in Superconductor Print Despite 30 years of intense study, the explanation behind the zero-resistance current displayed by high-temperature superconductors (HTSCs) is still shrouded in complexity. HTSCs tend to be heterogeneous materials with multiple phases, and disentangling their various electronic behaviors for analysis can be difficult. At the ALS, researchers used resonant soft x-ray diffraction (RSXD), a technique sensitive to both structure and electronic state at

  14. High temperature detonator

    DOE Patents [OSTI]

    Johnson, James O. (Los Alamos, NM); Dinegar, Robert H. (Los Alamos, NM)

    1988-01-01

    A detonator assembly is provided which is usable at high temperatures about 300.degree. C. A detonator body is provided with an internal volume defining an anvil surface. A first acceptor explosive is disposed on the anvil surface. A donor assembly having an ignition element, an explosive material, and a flying plate, are placed in the body effective to accelerate the flying plate to impact the first acceptor explosive on the anvil for detonating the first acceptor explosive. A second acceptor explosive is eccentrically located in detonation relationship with the first acceptor explosive to thereafter effect detonation of a main charge.

  15. Two Phase Transitions Make a High-Temperature Superconductor

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

    Note that various candidate orders for the pseudogap considered in this work give a qualitative agreement with the experiment in varying degrees. Research conducted by: R.-H....

  16. New advances in the modeling of high-temperature superconductors

    SciTech Connect (OSTI)

    Freitag, L.; Plassmann, P.; Jones, M.

    1994-03-01

    In this paper, we present a new discrete formulation that maintains discrete invariance and is suitable for use on nonorthogonal meshes. This formulation, unlike its predecessors, allows us to easily use adaptive mesh refinement to concentrate grid points where error contributions are large (near vortex centers). In this way we reduce the total number of grid points required to accurately capture vortex configurations and allow the possibility of solving problems previously considered intractable. To solve these large problems, we require the memory capabilities and computational power of state-of-the-art parallel computers. To use these machines, we have developed scalable libraries for adaptive mesh refinement and partitioning on two-dimensional triangular grids. This general-purpose software uses bisection of the longest side to refine triangles in which error contributions are large. These adaptive meshes are both unstructured and dynamic, and we present a new geometric partitioning, algorithm that strives to minimize communication cost by ensuring good partition aspect ratios. We present computational results showing the efficiency of these adaptive techniques for a superconductivity application.

  17. Two Phase Transitions Make a High-Temperature Superconductor

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

    the probe could permit a strong conclusion on the pseudogap phase transition, the small size of the overall signal previously measured in an yttrium-based cuprate was in strong...

  18. Two Phase Transitions Make a High-Temperature Superconductor

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

    and the small Kerr signal observed in different materials. Here, in this work, three research groups from Berkeley and Stanford report convincing data on the subject using a...

  19. Two Phase Transitions Make a High-Temperature Superconductor

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

    experiments on the pseudogap had rarely been performed; data recently obtained on a bismuth-based cuprate showed that the pseudogap opens rather abruptly below T* and evolves in...

  20. Two Phase Transitions Make a High-Temperature Superconductor

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

    revolutionary-is a quantum phenomenon in which bound electron pairs flow through a material in perfect synchrony, without friction. Conventional superconducting materials reach...

  1. Theory of intertwined orders in high temperature superconductors...

    Office of Scientific and Technical Information (OSTI)

    GrantContract Number: SC00112704 Type: Accepted Manuscript Journal Name: Reviews of Modern Physics Additional Journal Information: Journal Volume: 87; Journal Issue: 2; Journal...

  2. Advanced Conductor Development with High Temperature Superconductors and Carbon Nanotubes

    SciTech Connect (OSTI)

    Holesinger, Terry George

    2015-11-17

    This is a report that describes advanced conductor research performed by LANL in preparation for the Colloquia at the University of New Mexico.

  3. In the OSTI Collections: High-Temperature Superconductors | OSTI...

    Office of Scientific and Technical Information (OSTI)

    requires that their energy and momentum change by appropriate discrete finite amounts. ... can accelerate its electrons so they absorb energy from the field and flow among the ions. ...

  4. Fine uniform filament superconductors

    DOE Patents [OSTI]

    Riley, Jr., Gilbert N.; Li, Qi; Roberts, Peter R.; Antaya, Peter D.; Seuntjens, Jeffrey M.; Hancock, Steven; DeMoranville, Kenneth L.; Christopherson, Craig J.; Garrant, Jennifer H.; Craven, Christopher A.

    2002-01-01

    A multifilamentary superconductor composite having a high fill factor is formed from a plurality of stacked monofilament precursor elements, each of which includes a low density superconductor precursor monofilament. The precursor elements all have substantially the same dimensions and characteristics, and are stacked in a rectilinear configuration and consolidated to provide a multifilamentary precursor composite. The composite is thereafter thermomechanically processed to provide a superconductor composite in which each monofilament is less than about 50 microns thick.

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

    DOE Patents [OSTI]

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

    1981-01-14

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

  6. Improved ambient-pressure organic superconductor. [Bis(ethylenedithio)TTF-MX/sub 2/

    DOE Patents [OSTI]

    Williams, J.M.; Wang, Hsien-Hau; Beno, M.A.

    1985-05-29

    Disclosed is a new class of organic superconductors having the formula (ET)/sub 2/MX/sub 2/ wherein ET represents bis(ethylenedithio)-tetrathiafulvalene, M is a metal such as Au, Ag, In, Tl, Rb, Pd and the like and X is a halide. The superconductor (ET)/sub 2/AuI/sub 2/ exhibits a transition temperature of 5/sup 0/K which is high for organic superconductors.

  7. High temperature lubricating process

    DOE Patents [OSTI]

    Taylor, R.W.; Shell, T.E.

    1979-10-04

    It has been difficult to provide adequate lubrication for load bearing, engine components when such engines are operating in excess of about 475/sup 0/C. The present invention is a process for providing a solid lubricant on a load bearing, solid surface, such as in an engine being operated at temperatures in excess of about 475/sup 0/C. The process comprises contacting and maintaining the following steps: a gas phase is provided which includes at least one component reactable in a temperature dependent reaction to form a solid lubricant; the gas phase is contacted with the load bearing surface; the load bearing surface is maintained at a temperature which causes reaction of the gas phase component and the formation of the solid lubricant; and the solid lubricant is formed directly on the load bearing surface. The method is particularly suitable for use with ceramic engines.

  8. High temperature lubricating process

    DOE Patents [OSTI]

    Taylor, Robert W.; Shell, Thomas E.

    1982-01-01

    It has been difficult to provide adaquate lubrication for load bearing, engine components when such engines are operating in excess of about 475.degree. C. The present invention is a process for providing a solid lubricant on a load bearing, solid surface (14), such as in an engine (10) being operated at temperatures in excess of about 475.degree. C. The process comprises contacting and maintaining steps. A gas phase (42) is provided which includes at least one component reactable in a temperature dependent reaction to form a solid lubricant. The gas phase is contacted with the load bearing surface. The load bearing surface is maintained at a temperature which causes reaction of the gas phase component and the formation of the solid lubricant. The solid lubricant is formed directly on the load bearing surface. The method is particularly suitable for use with ceramic engines.

  9. High Temperature Fuel Cell Performance High Temperature Fuel Cell

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

    Performance of of Sulfonated Sulfonated Poly(phenylene Poly(phenylene) Proton) Proton Conducting Conducting Polymers | Department of Energy Cell Performance High Temperature Fuel Cell Performance of of Sulfonated Sulfonated Poly(phenylene Poly(phenylene) Proton) Proton Conducting Conducting Polymers High Temperature Fuel Cell Performance High Temperature Fuel Cell Performance of of Sulfonated Sulfonated Poly(phenylene Poly(phenylene) Proton) Proton Conducting Conducting Polymers Presentation

  10. Narrowband high temperature superconducting receiver for low frequency radio waves

    DOE Patents [OSTI]

    Reagor, David W.

    2001-01-01

    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.

  11. Maglev vehicles and superconductor technology: Integration of high-speed ground transportation into the air travel system

    SciTech Connect (OSTI)

    Johnson, L.R.; Rote, D.M.; Hull, J.R.; Coffey, H.T.; Daley, J.G.; Giese, R.F.

    1989-04-01

    This study was undertaken to (1) evaluate the potential contribution of high-temperature superconductors (HTSCs) to the technical and economic feasibility of magnetically levitated (maglev) vehicles, (2) determine the status of maglev transportation research in the United States and abroad, (3) identify the likelihood of a significant transportation market for high-speed maglev vehicles, and (4) provide a preliminary assessment of the potential energy and economic benefits of maglev systems. HTSCs should be considered as an enhancing, rather than an enabling, development for maglev transportation because they should improve reliability and reduce energy and maintenance costs. Superconducting maglev transportation technologies were developed in the United States in the late 1960s and early 1970s. Federal support was withdrawn in 1975, but major maglev transportation programs were continued in Japan and West Germany, where full-scale prototypes now carry passengers at speeds of 250 mi/h in demonstration runs. Maglev systems are generally viewed as very-high-speed train systems, but this study shows that the potential market for maglev technology as a train system, e.g., from one downtown to another, is limited. Rather, aircraft and maglev vehicles should be seen as complementing rather than competing transportation systems. If maglev systems were integrated into major hub airport operations, they could become economical in many relatively high-density US corridors. Air traffic congestion and associated noise and pollutant emissions around airports would also be reduced. 68 refs., 26 figs., 16 tabs.

  12. High-temperature-measuring device

    DOE Patents [OSTI]

    Not Available

    1981-01-27

    A temperature measuring device for very high design temperatures (to 2000/sup 0/C) is described. The device comprises a homogenous base structure preferably in the form of a sphere or cylinder. The base structure contains a large number of individual walled cells. The base structure has a decreasing coefficient of elasticity within the temperature range being monitored. A predetermined quantity of inert gas is confined within each cell. The cells are dimensonally stable at the normal working temperature of the device. Increases in gaseous pressure within the cells will permanently deform the cell walls at temperatures within the high temperature range to be measured. Such deformation can be correlated to temperature by calibrating similarly constructed devices under known time and temperature conditions.

  13. Development of YBCO Superconductor for Electric Systems: Cooperative

    Office of Scientific and Technical Information (OSTI)

    Research and Development Final Report, CRADA Number CRD-04-150 (Technical Report) | SciTech Connect Development of YBCO Superconductor for Electric Systems: Cooperative Research and Development Final Report, CRADA Number CRD-04-150 Citation Details In-Document Search Title: Development of YBCO Superconductor for Electric Systems: Cooperative Research and Development Final Report, CRADA Number CRD-04-150 The proposed project will be collaborative in exploration of high temperature

  14. Manufacturing High Temperature Systems

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

    Manufacturing and Scale Up Challenges Joseph Hartvigsen Ceramatec, Inc. National Renewable Energy Laboratory Golden, CO February 28, 2014 Antipode Assertions * Electric power generation is not the limitation - To misquote Jay Leno "Use all you want, we'll make more" - http://atomicinsights.com/2013/02/use-all-the-electricity-you-want-well-make-more.html * High electric costs come from working the demand curve from below rather than above * "Grid Storage" is a misleading

  15. High Temperature Thermoelectric Materials Characterization for...

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

    the High Temperature Materials Laboratory (HTML) User Program High Temperature ... the High Temperature Materials Laboratory (HTML) User Program 2009 DOE Hydrogen Program ...

  16. Ultra High Temperature | Open Energy Information

    Open Energy Info (EERE)

    Ultra High Temperature Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Sanyal Temperature Classification: Ultra High Temperature Dictionary.png Ultra High...

  17. Synthesis of highly phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor

    DOE Patents [OSTI]

    Dorris, Stephen E.; Poeppel, Roger B.; Prorok, Barton C.; Lanagan, Michael T.; Maroni, Victor A.

    1994-01-01

    An article and method of manufacture of (Bi,Pb)-Sr-Ca-Cu-O superconductor. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi,Pb)-Sr-Ca-Cu-O superconductor.

  18. Synthesis of highly phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor

    DOE Patents [OSTI]

    Dorris, S.E.; Poeppel, R.B.; Prorok, B.C.; Lanagan, M.T.; Maroni, V.A.

    1994-10-11

    An article and method of manufacture of (Bi,Pb)-Sr-Ca-Cu-O superconductor are disclosed. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi,Pb)-Sr-Ca-Cu-O superconductor. 5 figs.

  19. Aluminum-stabilized NB3SN superconductor

    DOE Patents [OSTI]

    Scanlan, Ronald M.

    1988-01-01

    An aluminum-stabilized Nb.sub.3 Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb.sub.3 Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials.

  20. High temperature turbine engine structure

    DOE Patents [OSTI]

    Boyd, Gary L.

    1990-01-01

    A high temperature turbine engine includes a hybrid ceramic/metallic rotor member having ceramic/metal joint structure. The disclosed joint is able to endure higher temperatures than previously possible, and aids in controlling heat transfer in the rotor member.

  1. High temperature structural insulating material

    DOE Patents [OSTI]

    Chen, Wayne Y.

    1987-01-01

    A high temperature structural insulating material useful as a liner for cylinders of high temperature engines through the favorable combination of high service temperature (above about 800.degree. C.), low thermal conductivity (below about 0.2 W/m.degree. C.), and high compressive strength (above about 250 psi). The insulating material is produced by selecting hollow ceramic beads with a softening temperature above about 800.degree. C., a diameter within the range of 20-200 .mu.m, and a wall thickness in the range of about 2-4 .mu.m; compacting the beads and a compatible silicate binder composition under pressure and sintering conditions to provide the desired structural form with the structure having a closed-cell, compact array of bonded beads.

  2. High temperature structural insulating material

    DOE Patents [OSTI]

    Chen, W.Y.

    1984-07-27

    A high temperature structural insulating material useful as a liner for cylinders of high temperature engines through the favorable combination of high service temperature (above about 800/sup 0/C), low thermal conductivity (below about 0.2 W/m/sup 0/C), and high compressive strength (above about 250 psi). The insulating material is produced by selecting hollow ceramic beads with a softening temperature above about 800/sup 0/C, a diameter within the range of 20-200 ..mu..m, and a wall thickness in the range of about 2 to 4 ..mu..m; compacting the beads and a compatible silicate binder composition under pressure and sintering conditions to provide the desired structural form with the structure having a closed-cell, compact array of bonded beads.

  3. High temperature current mirror amplifier

    DOE Patents [OSTI]

    Patterson, III, Raymond B.

    1984-05-22

    A high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is provided with a biasing means and current means on the input leg.

  4. Magnetic coherence in cuprate superconductors (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Subject: 36 MATERIALS SCIENCE; HIGH-TC SUPERCONDUCTORS; LANTHANUM OXIDES; STRONTIUM OXIDES; COPPER OXIDES; COHERENCE LENGTH; NEUTRON DIFFRACTION; MAGNETIZATION; MAGNETIC ...

  5. Encapsulation of High Temperature Thermoelectric Modules | Department...

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

    Encapsulation of High Temperature Thermoelectric Modules Encapsulation of High Temperature Thermoelectric Modules Presents concept for hermetic encapsulation of TE modules ...

  6. Microstabilized superconductor

    DOE Patents [OSTI]

    Bergmann, W.H.

    1971-08-17

    A microstabilized superconductor comprises a superconducting material of the hard Type II series sized in cross sectional area less than 1000 times the coherence length of the material.

  7. Microstabilized Superconductor

    DOE Patents [OSTI]

    Bergmann, W. H.

    1971-08-17

    A microstabilized superconductor comprises a superconducting material of the hard Type II series sized in cross sectional area less than 1000 times the coherence length of the material.

  8. NMR characterization of sulphur substitution effects in the KxFe2-ySe2-zSz high-Tc superconductor

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

    Torchetti, D. A.; Imai, T.; Lei, H. C.; Petrovic, C.

    2012-04-17

    We present a⁷⁷ Se NMR study of the effect of S substitution in the high-Tc superconductor KxFe2-ySe2-zSz in a temperature range up to 250 K. We examine two S concentrations, with z=0.8 (Tc~ 26 K) and z=1.6 (nonsuperconducting). The samples containing sulphur exhibit broader NMR line shapes than the KxFe₂Se₂ sample due to local disorder in the Se environment. Our Knight shift ⁷⁷K data indicate that in all samples, uniform spin susceptibility decreases with temperature, and that the magnitude of the Knight shift itself decreases with increased S concentration. In addition, S substitution progressively suppresses low-frequency spin fluctuations. None ofmore » the samples exhibit an enhancement of low-frequency antiferromagnetic spin fluctuations near Tc in 1/T₁T, as seen in FeSe.« less

  9. High temperature lightweight foamed cements

    DOE Patents [OSTI]

    Sugama, Toshifumi.

    1989-10-03

    Cement slurries are disclosed which are suitable for use in geothermal wells since they can withstand high temperatures and high pressures. The formulation consists of cement, silica flour, water, a retarder, a foaming agent, a foam stabilizer, and a reinforcing agent. A process for producing these cements is also disclosed. 3 figs.

  10. High temperature lightweight foamed cements

    DOE Patents [OSTI]

    Sugama, Toshifumi

    1989-01-01

    Cement slurries are disclosed which are suitable for use in geothermal wells since they can withstand high temperatures and high pressures. The formulation consists of cement, silica flour, water, a retarder, a foaming agent, a foam stabilizer, and a reinforcing agent. A process for producing these cements is also disclosed.

  11. High temperature electronic gain device

    DOE Patents [OSTI]

    McCormick, J. Byron; Depp, Steven W.; Hamilton, Douglas J.; Kerwin, William J.

    1979-01-01

    An integrated thermionic device suitable for use in high temperature, high radiation environments. Cathode and control electrodes are deposited on a first substrate facing an anode on a second substrate. The substrates are sealed to a refractory wall and evacuated to form an integrated triode vacuum tube.

  12. Temperature controlled high voltage regulator

    DOE Patents [OSTI]

    Chiaro, Jr., Peter J.; Schulze, Gerald K.

    2004-04-20

    A temperature controlled high voltage regulator for automatically adjusting the high voltage applied to a radiation detector is described. The regulator is a solid state device that is independent of the attached radiation detector, enabling the regulator to be used by various models of radiation detectors, such as gas flow proportional radiation detectors.

  13. Apex oxygen and critical temperature in copper oxide superconductors: Universal correlation with the stability of local singlets

    SciTech Connect (OSTI)

    Ohta, Y.; Tohyama, T.; Maekawa, S. )

    1991-02-01

    Electronic-energy-level structures of the layered Cu oxide compounds are drawn within the ionic model. Correlations between the level separations obtained and the superconducting critical temperature {ital T}{sub {ital c}} are examined for all families of the Cu oxide superconductors. It is proposed that the position of the energy level of the apex oxygen atoms is of primary importance for the electronic states of the CuO{sub 2} plane and governs the optimum {ital T}{sub {ital c}}'s of all families of hole-carrier suprconductors. The pressure effect of {ital T}{sub {ital c}} is discussed within this framework. Based on cluster-model calculations, where the covalency neglected in the ionic model is fully taken into account, we argue that the role of the apex oxygen atoms is to prescribe the stability of local singlet states made of two holes in the Cu 3{ital d}{sub {ital x}}{sup 2}{minus}{ital y}{sup 2} and O 2{ital p}{sub {sigma}} orbitals of the CuO{sub 2} plane, and thereby to control the maximum {ital T}{sub {ital c}} of each family.

  14. High temperature current mirror amplifier

    DOE Patents [OSTI]

    Patterson, R.B. III.

    1984-05-22

    Disclosed is a high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is provided with a biasing means and current means on the input leg. 2 figs.

  15. High temperature turbine engine structure

    DOE Patents [OSTI]

    Boyd, Gary L.

    1991-01-01

    A high temperature turbine engine includes a rotor portion having axially stacked adjacent ceramic rotor parts. A ceramic/ceramic joint structure transmits torque between the rotor parts while maintaining coaxial alignment and axially spaced mutually parallel relation thereof despite thermal and centrifugal cycling.

  16. Splicing of Superconductor Materials - Energy Innovation Portal

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

    Advanced Materials Advanced Materials Find More Like This Return to Search Splicing of Superconductor Materials Brookhaven National Laboratory Contact BNL About This Technology Technology Marketing Summary Low resistance splices are needed to join high temperature superconducting (HTS) materials in order to fabricate large-scale magnets for example, for accelerator, energy storage and medical applications. If the splice resistance is too high, the thermal, mechanical and electrical properties

  17. Low Cost, High Temperature, High Ripple Current DC Bus Capacitors...

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

    Low Cost, High Temperature, High Ripple Current DC Bus Capacitors Low Cost, High Temperature, High Ripple Current DC Bus Capacitors 2010 DOE Vehicle Technologies and Hydrogen...

  18. High-pressure, high-temperature plastic deformation of sintered...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: High-pressure, high-temperature plastic deformation of sintered diamonds Citation Details In-Document Search Title: High-pressure, high-temperature plastic ...

  19. High temperature two component explosive

    DOE Patents [OSTI]

    Mars, James E.; Poole, Donald R.; Schmidt, Eckart W.; Wang, Charles

    1981-01-01

    A two component, high temperature, thermally stable explosive composition comprises a liquid or low melting oxidizer and a liquid or low melting organic fuel. The oxidizer and fuel in admixture are incapable of substantial spontaneous exothermic reaction at temperatures on the order of 475.degree. K. At temperatures on the order of 475.degree. K., the oxidizer and fuel in admixture have an activation energy of at least about 40 kcal/mol. As a result of the high activation energy, the preferred explosive compositions are nondetonable as solids at ambient temperature, and become detonable only when heated beyond the melting point. Preferable oxidizers are selected from alkali or alkaline earth metal nitrates, nitrites, perchlorates, and/or mixtures thereof. Preferred fuels are organic compounds having polar hydrophilic groups. The most preferred fuels are guanidinium nitrate, acetamide and mixtures of the two. Most preferred oxidizers are eutectic mixtures of lithium nitrate, potassium nitrate and sodium nitrate, of sodium nitrite, sodium nitrate and potassium nitrate, and of potassium nitrate, calcium nitrate and sodium nitrate.

  20. High Temperature Heat Exchanger Project

    SciTech Connect (OSTI)

    Anthony E. Hechanova, Ph.D.

    2008-09-30

    The UNLV Research Foundation assembled a research consortium for high temperature heat exchanger design and materials compatibility and performance comprised of university and private industry partners under the auspices of the US DOE-NE Nuclear Hydrogen Initiative in October 2003. The objectives of the consortium were to conduct investigations of candidate materials for high temperature heat exchanger componets in hydrogen production processes and design and perform prototypical testing of heat exchangers. The initial research of the consortium focused on the intermediate heat exchanger (located between the nuclear reactor and hydrogen production plan) and the components for the hydrogen iodine decomposition process and sulfuric acid decomposition process. These heat exchanger components were deemed the most challenging from a materials performance and compatibility perspective

  1. High pressure and high temperature apparatus

    DOE Patents [OSTI]

    Voronov, Oleg A.

    2005-09-13

    A design for high pressure/high temperature apparatus and reaction cell to achieve .about.30 GPa pressure in .about.1 cm volume and .about.100 GPa pressure in .about.1 mm volumes and 20-5000.degree. C. temperatures in a static regime. The device includes profiled anvils (28) action on a reaction cell (14, 16) containing the material (26) to be processed. The reaction cell includes a heater (18) surrounded by insulating layers and screens. Surrounding the anvils are cylindrical inserts and supporting rings (30-48) whose hardness increases towards the reaction cell. These volumes may be increased considerably if applications require it, making use of presses that have larger loading force capability, larger frames and using larger anvils.

  2. HIGH TEMPERATURE MICROSCOPE AND FURNACE

    DOE Patents [OSTI]

    Olson, D.M.

    1961-01-31

    A high-temperature microscope is offered. It has a reflecting optic situated above a molten specimen in a furnace and reflecting the image of the same downward through an inert optic member in the floor of the furnace, a plurality of spaced reflecting plane mirrors defining a reflecting path around the furnace, a standard microscope supported in the path of and forming the end terminus of the light path.

  3. High temperature turbine engine structure

    DOE Patents [OSTI]

    Carruthers, William D.; Boyd, Gary L.

    1992-01-01

    A high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic spacer assembly maintains the close running clearance of the shroud portion and rotor member despite differential thermal movements between the shroud portion and metallic housing portion.

  4. High temperature turbine engine structure

    DOE Patents [OSTI]

    Carruthers, William D.; Boyd, Gary L.

    1993-01-01

    A high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic spacer assembly maintains the close running clearance of the shroud portion and rotor member despite differential thermal movements between the shroud portion and metallic housing portion.

  5. High temperature turbine engine structure

    DOE Patents [OSTI]

    Carruthers, William D.; Boyd, Gary L.

    1994-01-01

    A high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic spacer assembly maintains the close running clearance of the shroud portion and rotor member despite differential thermal movements between the shroud portion and metallic housing portion.

  6. Nanostructured High Temperature Bulk Thermoelectric Energy Conversion...

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

    High Temperature Bulk Thermoelectric Energy Conversion for Efficient Waste Heat Recovery Nanostructured High Temperature Bulk Thermoelectric Energy Conversion for Efficient Waste ...

  7. High-Temperature Thermoelectric Materials Characterization for...

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

    High-Temperature Thermoelectric Materials Characterization for Automotive Waste Heat Recovery: Success Stories from the High Temperature Materials Laboratory (HTML) User Program...

  8. Improved Martensitic Steel for High Temperature Applications...

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

    Improved Martensitic Steel for High Temperature Applications A stainless steel composition and heat treatment process for a high-temperature, titanium alloyed 9 Cr-1 molybdenum ...

  9. High-Temperature Superconductivity Cable Demonstration Projects...

    Energy Savers [EERE]

    High-Temperature Superconductivity Cable Demonstration Projects High-Temperature Superconductivity Cable Demonstration Projects A National Effort to Introduce New Technology into ...

  10. Superconductor Composite

    DOE Patents [OSTI]

    Dorris, Stephen E.; Burlone, Dominick A.; Morgan; Carol W.

    1999-02-02

    A superconducting conductor fabricated from a plurality of wires, e.g., fine silver wires, coated with a superconducting powder. A process of applying superconducting powders to such wires, to the resulting coated wires and superconductors produced therefrom.

  11. High thermoelectric figure of merit in nanocrystalline polyaniline at low temperatures

    SciTech Connect (OSTI)

    Nath, Chandrani; Kumar, Ashok E-mail: okram@csr.res.in; Kuo, Yung-Kang; Okram, Gunadhor Singh E-mail: okram@csr.res.in

    2014-09-29

    Thermoelectric coolers with figure of merit (ZT) close to unity at low temperatures are the need of the hour with new advances in high temperature superconductors, superconducting microelectronic circuits, quantum computers, and photonics. Here, we demonstrate that the conducting polymer polyaniline (Pani) doped with camphor sulfonic acid synthesized in semi-crystalline nanostructures, possesses a giant Seebeck effect at low temperatures. The resulting enormously large Seebeck coefficient (up to 0.6 V/K) combined with an intrinsically low electrical conductivity and thermal conductivity give rise to a ZT = 0.77 at 45 K and ZT = 2.17 at 17 K.

  12. High-Temperature-High-Volume Lifting for Enhanced Geothermal...

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

    More Documents & Publications High-Temperature-High-Volume Lifting for Enhanced Geothermal Systems High-Temperature Motor Windings for Downhole Pumps Used in Geothermal Energy ...

  13. CONFINEMENT OF HIGH TEMPERATURE PLASMA

    DOE Patents [OSTI]

    Koenig, H.R.

    1963-05-01

    The confinement of a high temperature plasma in a stellarator in which the magnetic confinement has tended to shift the plasma from the center of the curved, U-shaped end loops is described. Magnetic means are provided for counteracting this tendency of the plasma to be shifted away from the center of the end loops, and in one embodiment this magnetic means is a longitudinally extending magnetic field such as is provided by two sets of parallel conductors bent to follow the U-shaped curvature of the end loops and energized oppositely on the inside and outside of this curvature. (AEC)

  14. High temperature sealed electrochemical cell

    DOE Patents [OSTI]

    Valentin Chung, Brice Hoani; Burke, Paul J.; Sadoway, Donald R.

    2015-10-06

    A cell for high temperature electrochemical reactions is provided. The cell includes a container, at least a portion of the container acting as a first electrode. An extension tube has a first end and a second end, the extension tube coupled to the container at the second end forming a conduit from the container to said first end. A second electrode is positioned in the container and extends out of the container via the conduit. A seal is positioned proximate the first end of the extension tube, for sealing the cell.

  15. Detection of surface impurity phases in high T.sub.C superconductors using thermally stimulated luminescence

    DOE Patents [OSTI]

    Cooke, D. Wayne; Jahan, Muhammad S.

    1989-01-01

    Detection of surface impurity phases in high-temperature superconducting materials. Thermally stimulated luminescence has been found to occur in insulating impurity phases which commonly exist in high-temperature superconducting materials. The present invention is sensitive to impurity phases occurring at a level of less than 1% with a probe depth of about 1 .mu.m which is the region of interest for many superconductivity applications. Spectroscopic and spatial resolution of the emitted light from a sample permits identification and location of the impurity species. Absence of luminescence, and thus of insulating phases, can be correlated with low values of rf surface resistance.

  16. Materials Characterization Capabilities at the High Temperature...

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

    Temperature Materials Laboratory (HTML) User Program Materials Characterization Capabilities at the High Temperature Materials Laboratory and HTML User Program Success Stories ...

  17. Faraday imaging at high temperatures

    DOE Patents [OSTI]

    Hackel, Lloyd A.; Reichert, Patrick

    1997-01-01

    A Faraday filter rejects background light from self-luminous thermal objects, but transmits laser light at the passband wavelength, thus providing an ultra-narrow optical bandpass filter. The filter preserves images so a camera looking through a Faraday filter at a hot target illuminated by a laser will not see the thermal radiation but will see the laser radiation. Faraday filters are useful for monitoring or inspecting the uranium separator chamber in an atomic vapor laser isotope separation process. Other uses include viewing welds, furnaces, plasma jets, combustion chambers, and other high temperature objects. These filters are can be produced at many discrete wavelengths. A Faraday filter consists of a pair of crossed polarizers on either side of a heated vapor cell mounted inside a solenoid.

  18. Faraday imaging at high temperatures

    DOE Patents [OSTI]

    Hackel, L.A.; Reichert, P.

    1997-03-18

    A Faraday filter rejects background light from self-luminous thermal objects, but transmits laser light at the passband wavelength, thus providing an ultra-narrow optical bandpass filter. The filter preserves images so a camera looking through a Faraday filter at a hot target illuminated by a laser will not see the thermal radiation but will see the laser radiation. Faraday filters are useful for monitoring or inspecting the uranium separator chamber in an atomic vapor laser isotope separation process. Other uses include viewing welds, furnaces, plasma jets, combustion chambers, and other high temperature objects. These filters are can be produced at many discrete wavelengths. A Faraday filter consists of a pair of crossed polarizers on either side of a heated vapor cell mounted inside a solenoid. 3 figs.

  19. System and method for quench and over-current protection of superconductor

    DOE Patents [OSTI]

    Huang, Xianrui; Laskaris, Evangelos Trifon; Sivasubramaniam, Kiruba Haran; Bray, James William; Ryan, David Thomas; Fogarty, James Michael; Steinbach, Albert Eugene

    2005-05-31

    A system and method for protecting a superconductor. The system may comprise a current sensor operable to detect a current flowing through the superconductor. The system may comprise a coolant temperature sensor operable to detect the temperature of a cryogenic coolant used to cool the superconductor to a superconductive state. The control circuit is operable to estimate the superconductor temperature based on the current flow and the coolant temperature. The system may also be operable to compare the estimated superconductor temperature to at least one threshold temperature and to initiate a corrective action when the superconductor temperature exceeds the at least one threshold temperature.

  20. High temperature control rod assembly

    SciTech Connect (OSTI)

    Vollman, Russell E.

    1991-01-01

    A high temperature nuclear control rod assembly comprises a plurality of substantially cylindrical segments flexibly joined together in succession by ball joints. The segments are made of a high temperature graphite or carbon-carbon composite. The segment includes a hollow cylindrical sleeve which has an opening for receiving neutron-absorbing material in the form of pellets or compacted rings. The sleeve has a threaded sleeve bore and outer threaded surface. A cylindrical support post has a threaded shaft at one end which is threadably engaged with the sleeve bore to rigidly couple the support post to the sleeve. The other end of the post is formed with a ball portion. A hollow cylindrical collar has an inner threaded surface engageable with the outer threaded surface of the sleeve to rigidly couple the collar to the sleeve. the collar also has a socket portion which cooperates with the ball portion to flexibly connect segments together to form a ball and socket-type joint. In another embodiment, the segment comprises a support member which has a threaded shaft portion and a ball surface portion. The threaded shaft portion is engageable with an inner threaded surface of a ring for rigidly coupling the support member to the ring. The ring in turn has an outer surface at one end which is threadably engageably with a hollow cylindrical sleeve. The other end of the sleeve is formed with a socket portion for engagement with a ball portion of the support member. In yet another embodiment, a secondary rod is slidably inserted in a hollow channel through the center of the segment to provide additional strength. A method for controlling a nuclear reactor utilizing the control rod assembly is also included.

  1. High-temperature Pump Monitoring - High-temperature ESP Monitoring...

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

    DOE 2010 Geothermal Technologies Program Peer Review hightemp018dhruva.pdf (188.95 KB) More Documents & Publications Development of Tools for Measuring Temperature, Flow, ...

  2. Method for preparing superconductors

    DOE Patents [OSTI]

    Dahlgren, Shelley D.

    1976-01-01

    A superconductor having an equiaxed fine grain beta-tungsten crystalline structure found to have improved high field critical current densities is prepared by sputter-depositing superconductive material onto a substrate cooled to below 200.degree. C. and heat-treating the deposited material.

  3. Electron Correlation in Iron-Based Superconductors

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

    Electron Correlation in Iron-Based Superconductors Electron Correlation in Iron-Based Superconductors Print Wednesday, 24 February 2010 00:00 In 2008, the discovery of iron-based superconductors stimulated a worldwide burst of activity, leading to about two preprints per day ever since. With a maximum superconducting transition temperature (so far) of 55 K, it is natural to wonder if studying the new materials will help uncover one of the deepest mysteries in modern physics-the mechanism of

  4. Thermal disconnect for high-temperature batteries

    DOE Patents [OSTI]

    Jungst, Rudolph George; Armijo, James Rudolph; Frear, Darrel Richard

    2000-01-01

    A new type of high temperature thermal disconnect has been developed to protect electrical and mechanical equipment from damage caused by operation at extreme temperatures. These thermal disconnects allow continuous operation at temperatures ranging from 250.degree. C. to 450.degree. C., while rapidly terminating operation at temperatures 50.degree. C. to 150.degree. C. higher than the continuous operating temperature.

  5. High-Pressure and High-Temperature Powder Diffraction (Journal...

    Office of Scientific and Technical Information (OSTI)

    High-Pressure and High-Temperature Powder Diffraction Citation Details In-Document Search Title: High-Pressure and High-Temperature Powder Diffraction Authors: Fei, Yingwei ; Wang, ...

  6. High Temperature, High Pressure Devices for Zonal Isolation in Geothermal

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

    Wells | Department of Energy High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells fabian_ctd_ zonal_isolation_peer2013.pdf (809.57 KB) More Documents & Publications High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells track 3: enhanced geothermal systems (EGS) | geothermal 2015

  7. Aluminum-stabilized Nb[sub 3]Sn superconductor

    DOE Patents [OSTI]

    Scanlan, R.M.

    1988-05-10

    Disclosed are an aluminum-stabilized Nb[sub 3]Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb[sub 3]Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials. 4 figs.

  8. Aluminum-stabilized Nb/sub 3/Sn superconductor

    DOE Patents [OSTI]

    Scanlan, R.M.

    1984-02-10

    This patent discloses an aluminum-stabilized Nb/sub 3/Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb/sub 3/Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials.

  9. High-temperature thermocouples and related methods

    DOE Patents [OSTI]

    Rempe, Joy L.; Knudson, Darrell L.; Condie, Keith G.; Wilkins, S. Curt

    2011-01-18

    A high-temperature thermocouple and methods for fabricating a thermocouple capable of long-term operation in high-temperature, hostile environments without significant signal degradation or shortened thermocouple lifetime due to heat induced brittleness.

  10. High Temperature Superconducting Underground Cable

    SciTech Connect (OSTI)

    Farrell, Roger, A.

    2010-02-28

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

  11. Materials Characterization Capabilities at the High Temperature...

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

    Lightweighting Materials Materials Characterization Capabilities at the High Temperature Materials Laboratory: Focus Lightweighting Materials 2011 DOE Hydrogen and Fuel Cells ...

  12. Materials Characterization Capabilities at the High Temperature...

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

    More Documents & Publications Materials Characterization Capabilities at the High Temperature Materials Laboratory and HTML User Program Success Stories Materials Characterization ...

  13. High Temperature Superconductivity Partners | Department of Energy

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

    High Temperature Superconductivity Partners Map showing DOE's partnersstakeholders in the ... More Documents & Publications DOE Superconductivity Program Stakeholders DOE Provides up ...

  14. Compensated electron and hole pickets in an underdoped high Tc superconductor

    SciTech Connect (OSTI)

    Harrison, Neil; Altarawneh, Moaz M; Mielke, Charles H; Sebastian, Suchitra E; Goddard, P A; Liang, Ruixing; Bonn, D A; Hardy, W N; Andersen, O K; Lonzarich, G G

    2010-01-01

    Important to the question of high temperature superconductivity is whether bound fermionic pairs with zero or finite momentum - exhibiting bosonic physics - are involved. Here we use angle-dependent magnetic quantum oscillation measurements in underdoped YBa{sub 2}Cu{sub 3}O{sub 6+x} to reveal two significantly differently corrugated small sections of Fermi surface, identifying them as comprising opposite carriers located at different locations of the Brillouin zone. The surprising finding that these disproportionately heavy small pockets are equal in size indicates they are prone to a finite momentum excitonic insulator instability. We discuss the possibility that reducing the doping drives YBa{sub 2}Cu{sub 3}O{sub 6+x} closer to an instability of this nature, its ultimate realization occuring at the metal-insulator quantum critical point, accompanied by a potential enhancement of superconducting transition temperatures.

  15. Measurement of thermodynamic temperature of high temperature fixed points

    SciTech Connect (OSTI)

    Gavrilov, V. R.; Khlevnoy, B. B.; Otryaskin, D. A.; Grigorieva, I. A.; Samoylov, M. L.; Sapritsky, V. I.

    2013-09-11

    The paper is devoted to VNIIOFI's measurements of thermodynamic temperature of the high temperature fixed points Co-C, Pt-C and Re-C within the scope of the international project coordinated by the Consultative Committee for Thermometry working group 5 'Radiation Thermometry'. The melting temperatures of the fixed points were measured by a radiance mode radiation thermometer calibrated against a filter radiometer with known irradiance spectral responsivity via a high temperature black body. This paper describes the facility used for the measurements, the results and estimated uncertainties.

  16. New MIT design revives interest in high-field approach to fusion

    SciTech Connect (OSTI)

    Kramer, David

    2015-10-15

    Tokamaks made with high-temperature superconductors may offer a less expensive, more compact route to fusion power, if their coils can withstand the tremendous forces.

  17. Radiation detector using a bulk high T[sub c] superconductor

    DOE Patents [OSTI]

    Artuso, J.F.; Franks, L.A.; Hull, K.L.; Symko, O.G.

    1993-12-07

    A radiation detector is provided, wherein a bulk high T[sub c] superconducting sample is placed in a magnetic field and maintained at a superconducting temperature. Photons of incident radiation will cause localized heating in superconducting loops of the sample destroying trapped flux and redistributing the fluxons, and reducing the critical current of the loops. Subsequent cooling of the sample in the magnetic field will cause trapped flux redistributed Abrikosov fluxons and trapped Josephson fluxons. The destruction and trapping of the fluxons causes changes in the magnetization of the sample inducing currents in opposite directions in a pickup coil which is coupled by an input coil to an rf SQUID. 4 figures.

  18. Superconductor cable

    DOE Patents [OSTI]

    Smith, Jr., Darrell F.; Lake, Bill L.; Ballinger, Ronald G.

    1988-01-01

    A superconducting cable comprising an in-situ-formed type II superconductor, e.g. Nb.sub.3 Sn, in association with a stabilizing conductor both in heat transfer relationship with at least one passage adapted to carry liquified gaseous refrigerant. The conductor and said at least one passage are enclosed by a sheath comprising an alloy consisting essentially of about 49% nickel, about 4% chromium, about 3% niobium, about 1.4% titanium, about 1% aluminum, balance essentially iron.

  19. Deep Trek High Temperature Electronics Project

    SciTech Connect (OSTI)

    Bruce Ohme

    2007-07-31

    This report summarizes technical progress achieved during the cooperative research agreement between Honeywell and U.S. Department of Energy to develop high-temperature electronics. Objects of this development included Silicon-on-Insulator (SOI) wafer process development for high temperature, supporting design tools and libraries, and high temperature integrated circuit component development including FPGA, EEPROM, high-resolution A-to-D converter, and a precision amplifier.

  20. High Temperature ESP Monitoring | Department of Energy

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

    The purpose of the High Temperature ESP Monitoring project is to develop a down-hole monitoring system to be used in wells with bottom hole temperature up to 300 C for measuring ...

  1. Preparation of superconductor precursor powders

    DOE Patents [OSTI]

    Bhattacharya, Raghunath

    1998-01-01

    A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

  2. Simultaneous constraint and phase conversion processing of oxide superconductors

    DOE Patents [OSTI]

    Li, Qi; Thompson, Elliott D.; Riley, Jr., Gilbert N.; Hellstrom, Eric E.; Larbalestier, David C.; DeMoranville, Kenneth L.; Parrell, Jeffrey A.; Reeves, Jodi L.

    2003-04-29

    A method of making an oxide superconductor article includes subjecting an oxide superconductor precursor to a texturing operation to orient grains of the oxide superconductor precursor to obtain a highly textured precursor; and converting the textured oxide superconducting precursor into an oxide superconductor, while simultaneously applying a force to the precursor which at least matches the expansion force experienced by the precursor during phase conversion to the oxide superconductor. The density and the degree of texture of the oxide superconductor precursor are retained during phase conversion. The constraining force may be applied isostatically.

  3. Manufacturing Barriers to High Temperature PEM Commercialization |

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

    Department of Energy Barriers to High Temperature PEM Commercialization Manufacturing Barriers to High Temperature PEM Commercialization Presented at the NREL Hydrogen and Fuel Cell Manufacturing R&D Workshop in Washington, DC, August 11-12, 2011. Manufacturing Barriers to High Temperature PEM Commercialization (785.02 KB) More Documents & Publications PBI-Phosphoric Acid Based Membrane Electrode Assemblies: Status Update MCFC and PAFC R&D Workshop Summary Report 2012 Pathways to

  4. Electrolysis - High Temperature - Hydrogen - Energy Innovation Portal

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

    Electrolysis - High Temperature - Hydrogen Idaho National Laboratory Contact INL About This Technology Technology Marketing Summary INL has developed a high-temperature process the utilizes solid oxide fuel cells that are operated in the electrolytic mode. The first process includes combining a high-temperature heat source (e.g. nuclear reactor) with a hydrogen production facility by taking a stream of water and heating it and then splitting the water into hydrogen and oxygen product streams. A

  5. High-temperature brazed ceramic joints

    DOE Patents [OSTI]

    Jarvinen, Philip O.

    1986-01-01

    High-temperature joints formed from metallized ceramics are disclosed wherein the metal coatings on the ceramics are vacuum sputtered thereon.

  6. Materials Characterization Capabilities at the High Temperature...

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

    Laboratory and HTML User Program Success Stories Materials Characterization Capabilities at the High Temperature Materials Laboratory and HTML User Program Success Stories 2012 DOE ...

  7. Materials Characterization Capabilities at the High Temperature...

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

    Materials Laboratory and HTML User Program Success Stories Materials Characterization Capabilities at the High Temperature Materials Laboratory and HTML User Program Success ...

  8. Quantitative Modeling of High Temperature Magnetization Dynamics

    SciTech Connect (OSTI)

    Zhang, Shufeng

    2009-03-01

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

  9. Materials Characterization Capabilities at the High Temperature...

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

    -- Washington D.C. PDF icon lm028laracurzio2010o.pdf More Documents & Publications Materials Characterization Capabilities at the High Temperature Materials Laboratory and...

  10. High-temperature superconductivity: A conventional conundrum...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: High-temperature superconductivity: A conventional conundrum Citation ... OSTI Identifier: 1245373 Report Number(s): BNL--111729-2016-JA Journal ID: ISSN 1745-2473; ...