English

Superconducting transition in disordered granular superconductors in magnetic fields

Superconductivity 2009-11-11 v5

Abstract

Motivated by a recent argument that the superconducting (SC) transition field of three-dimensional (3D) disordered superconductors with granular structure in a nonzero magnetic field should lie above Hc2(0)H_{c2}(0) in low TT limit, the glass transition (or, in 2D, crossover) curve Hg(T)H_g(T) of disordered quantum Josephson junction arrays is examined by incorporating SC fluctuations. It is found that the glass transition or crossover in the granular materials can be described on the same footing as the vortex-glass (VG) transition in amorphous-like (i.e., nongranular) materials. In most of 3D granular systems, the vanishing of resistivity upon cooling should occur even above Hc2(0)H_{c2}(0), while the corresponding sharp drop of the resistivity in 2D case may appear only below Hc2H_{c2} as a result of an enhanced quantum fluctuation.

Keywords

Cite

@article{arxiv.cond-mat/0510380,
  title  = {Superconducting transition in disordered granular superconductors in magnetic fields},
  author = {Ryusuke Ikeda},
  journal= {arXiv preprint arXiv:cond-mat/0510380},
  year   = {2009}
}

Comments

Accepted for publication in Phys. Rev. B. The content of sec.3 in v.2 was removed from here and presented more extensively in a separate paper (cond-mat/0606522) where the argument of nonsuperconducting vortex-glass in cond-mat/0512432 is shown to be false

R2 v1 2026-07-22T11:24:03.492Z