Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1572-9605
    Keywords: YBa2Cu3O7−δ ; resistivity ; thermoelectric power
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract Four-probe resistivity (ρ) and thermoelectric power (TEP) measurements were carried out on samples of YBa2Cu3O7−δ up to 950°C, in air and in flowing oxygen at 1 bar. Below 700 K the TEP is small and increases rapidly above it, reaching, at 1200 K, +140μV/K in air and +120μV/K in oxygen. At the changeover temperature (700 K) the slope of logρ vs.T changes abruptly. These results are interpreted in terms of a model of transport of carriers in a narrow band, which is full forδ = 1 and half-filled forδ = 0. Possible origins for such a narrow band are discussed in detail.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of superconductivity 1 (1988), S. 441-450 
    ISSN: 1572-9605
    Keywords: Josephson junction ; logic device ; nonlinear inductance ; DCFP ; inductive logic device
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract Inductive Josephson logic (IJL) is realized by using Josephson junctions as a kind of nonlinear inductance. The operational principle of inductive Josephson logic is studied from a very simple example and generalized to multiple Josephson inductive logic devices. Concepts offorward andbackward are introduced to describe the states of the operations. IJLs operate in terms of current or flux; they are suitable to be used in connection with other flux-control Josephson circuit devices such as DC SQUID or DCFP. Some circuit devices based on the principle of inductive Josephson logic are given as examples of IJL logic functions.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1572-9605
    Keywords: Superconductivity ; research opportunities ; state of the art
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract This report surveys the considerable progress made over the last five years—such as the marketing of superconducting quantum interference devices (SQUIDs), cellular wireless filter systems, and high current leads—and assesses needs and opportunities in the areas of fundamental science, materials development, thin film and device applications, and wire and bulk applications. It examines the challenges facing high-temperature superconductivity: from the need to understand the mechanism of high-temperature superconductivity and the unusual “normal” state to the need for new instrumentation for material characterization. Advances in thin film and bulk materials are reviewed, and obstacles impeding the commercialization of HTS materials are examined.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1572-9605
    Keywords: Single crystal of Bi2Sr2CaCu2O8 ; high-resolution electron microscopy ; low-temperature electron diffraction ; lattice anomaly
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract High-resolution electron microscopy of a Bi2Sr2CaCu2O8 (Bi2212) single crystal prepared by the floating zone method shows that the single crystal is of high quality; there is no intergrowth faulting in the layered structure along the c-axis. Low-temperature selected area diffraction and convergent beam electron diffraction (CBED) studies of this high-quality single crystal show that there is no detectable change for both the point group symmetry of the basic structure and the modulated structure from room temperature to about 15 K. However, a lattice anomaly around 215 K was suggested by measuring the temperature dependence of the ratio between the cross-point distances of the HOLZ lines in high-index CBED patterns. The presence of the lattice anomaly was further confirmed by low-temperature X-ray diffraction.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1572-9605
    Keywords: High-T c superconductors ; order parameter ; Josephson junctions ; Josephson critical current ; pair symmetry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract An intrinsic gap depression at the superconductor–insulator interface due to the very short value of the coherence length in high-T c superconductors [HTS] is considered in the framework of a mixed (s+id)-wave pair symmetry for the order parameter ranging from pure s to pure d-wave. This gap depression acts as the main physical agent causing the relevant reduction of I c (T)R n (T) values with respect to BCS expectations in HTS SIS Josephson junctions. Good agreement with various experimental data is obtained with both pure s-wave and pure d-wave symmetries of the order parameter, but with amounts of gap depression depending on the pair symmetry adopted. Regardless of the pair symmetry considered, these results prove the importance of the surface order-parameter depression in the correct interpretation of the I c (T)R n (T) data in HTS SIS junctions. In the case of a planar YBCO-based junction the use of the de Gennes condition allowed us to tentatively obtain an upper limit for the amount of d-wave present in the gap of YBCO.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1572-9605
    Keywords: Stability ; degradation ; a-axis grain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract Highly a-axis oriented HgBa2CaCu2Ox thin films deposited on LaAlO3 substrates have been exposed to air at room temperature for a period of 400 days. The properties of the exposed sample have been studied by electrical and magnetic measurements, X- ray diffractometry (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDX). No substancial change of superconducting transition temperature or the structure was observed, but c-peaks reappeared after O2 re-annealing at 350°C for 16 h.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1572-9605
    Keywords: Tl- and Hg-superconductors ; oxygen content ; Cu-valence ; hole-doping mechanism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract In superconducting MmA2Qn−lCunOm+2+2n±δ phases the charge of the Qn−lCunO2n infinite-layer block depends in general on the charge of the MmOm±δ charge-reservoir block, which at a certain metal constituent Mm can be tuned by changing the oxygen stoichiometry δ. In the Tl- and Hg- based cuprates, however, determination of the exact oxygen content does not alone define the charge of the MmOm±δ unit, since both Tl and Hg may exhibit mixed-valent states. For a quantitative estimation of the charge balances, both wet chemical redox analyses and bond-valence calculations are utilized. Furthermore, based on the results of the bond-valence calculations, three different routes of hole-doping the CuO2 planes are distinguished, and the actual conductance of these routes is discussed in several different Tl/Hg-m2(n-l)n phases.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1572-9605
    Keywords: Flux dynamics ; vortex phase diagram ; irreversibility line
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract Investigations on flux dynamics of ring-shaped T12Ba2CaCu2O8 superconducting thin films have been carried out by measuring the temperature dependent magnetization M(T) during field-cooling (FC) and zero-field-cooling (ZFC) processes. For a given magnetic field, from the magnetization behavior two distinct temperatures, Tkink and Tirr, can be defined. Below Tkink, a clear hysteretic behavior of M(T) is observed leading to a large irreversible signal ΔM = MFC − MZFC. Above Tkink, this irreversible signal, though being very small, is still non-zero until it eventually vanishes at a higher temperature Tirr. Above Tirr, both curves MFC(T) and MZFC(T) merge together and become temperature independent. We attribute the first region ( T〈 Tkink) to a 3D vortex-glass phase, the second region (Tkink 〈 T 〈 Tirr) to a vortex line liquid state and the third region (Tirr 〈 T 〈 Tc) to a pancake liquid state.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1572-9605
    Keywords: Tl-based thin films ; critical currents ; flux-creep ; weak links
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract Superconducting Tl-Ba-Ca-Cu-O thin film microstrips were prepared on MgO substrates by thallination of the lift-off patterned Ba-Ca-Cu-O precursor films.The highest zero-resistance critical temperare Tco of microstrips was 94 K. From the critical current vs. temperature dependence two various critical current limiting mechanisms were distinguished.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1572-9605
    Keywords: EBSD ; microstructure ; superconductor ; surface resistance ; TBCCO
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract Tl2Ba2Ca2Cu3Ox thin films have been fabricated on (001) LaAlO3 and (001) MgO substrates. Films grown on LaAlO3 have Tc=112K and RS(80K, 10GHz)=0.2mΩ, while films on MgO have Tc=117K and Rs(80K, 10GHz)=0.7mΩ. The grain size and alignment of the films has been investigated using X-ray diffraction, Scanning Electron Microscopy and Electron Backscattered Diffraction. We show evidence for a markedly higher in-plane angular spread for films on MgO and believe that for films grown on this substrate the lowest achievable values of Rs are limited by disorder in the in-plane alignment of the TBCCO film caused by the large lattice mismatch between the materials.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...