Flux Pinning Property of Artificially Introduced Nb in Nb-Ti Superconductors

  • T. Matsushita
  • M. Iwakuma
  • K. Funaki
  • K. Yamafuji
  • K. Matsumoto
  • O. Miura
  • Y. Tanaka
Part of the Advances in Cryogenic Engineering Materials book series (ACRE, volume 42)

Abstract

The elementary pinning force of thin Nb layers introduced as artificial pinning centers in Nb-Ti is theoretically investigated in the relatively low field region using the Ginzburg-Landau theory. It is found that the pinning energy comes from the kinetic energy due to the induced superconductivity in the Nb layers by the proximity effect. Hence, these layers act as repulsive pinning centers, while normal layers such as α-Ti do as attractive ones. The elementary pinning force depends sensitively on the coherence length in the Nb layers and is larger for the longer coherence length. This value is predicted to be larger than that of α-Ti layers in commercial Nb-Ti wires even in the case of short coherence length.

Keywords

Critical Current Density Coherence Length Critical Field Proximity Effect Normal Core 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • T. Matsushita
    • 1
  • M. Iwakuma
    • 2
  • K. Funaki
    • 2
  • K. Yamafuji
    • 2
  • K. Matsumoto
    • 3
  • O. Miura
    • 4
  • Y. Tanaka
    • 5
  1. 1.Department of Computer Science and ElectronicsKyushu Institute of TechnologyIizuka 820Japan
  2. 2.Faculty of EngineeringKyushu UniversityHigashi-ku Fukuoka 820Japan
  3. 3.Yokohama R&D LaboratoriesThe Furukawa Electric Co. Ltd.Nishi-ku, Yokohama 220Japan
  4. 4.Chiba R&D LaboratoriesThe Furukawa Electric Co. Ltd.Ichihara 290Japan
  5. 5.Metal Research CenterThe Furukawa Electric Co. Ltd.NikkoJapan

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