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Czechoslovak Journal of Physics B

, Volume 36, Issue 4, pp 524–536 | Cite as

Properties of superfine superconducting filaments embedded in normal matrix

  • S. Takács
Article

Abstract

The size-, surface- and proximity-effects are combined for calculating the critical temperature and some unusual electromagnetic properties of superfine superconducting NbTi filaments (i.e. with a diameterds < 0·1 μm) in the neighbourhood of normal metal (Cu). It is shown that the existence of the one-dimensional flux line lattice is responsible for the extremely large values of the critical current densities in low magnetic fields (B < 0·2Bc2,Bc2 — the upper critical magnetic field), for the maximum of the volume pinning force at low magnetic fields (Bm ≈ 0·1Bc2, comparing withBm≈ 0·5Bc2 in usual macroscopic multifilamentary NbTi superconductors), as well as for the peculiar minimum of the magnetization after reversing the magnetic field direction. The possible role of the frozen-in flux lines in creating flux lines of opposite direction is sketched. It is proposed that for practical purposes the superconducting filaments should be coated with electrically insulating material (e.g. cupro-nickel or dielectric) to destroy the electro-magnetic coupling between the filaments and to ensure low ac losses in the composite.

Keywords

Magnetic Field Critical Temperature Practical Purpose Line Lattice Critical Current Density 
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

© Academia, Publishing House of the Czechoslovak Academy of Sciences 1986

Authors and Affiliations

  • S. Takács
    • 1
  1. 1.Electrotechnical Institute, Electro-Physical Research CentreSlovak Acad. Sci.BratislavaCzechoslovakia

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