English

Disorder induced non-Fermi liquid near a metal-superconductor quantum phase transition

Superconductivity 2007-05-23 v1 Disordered Systems and Neural Networks

Abstract

We study the flux-driven superconductor-metal transition in ultrasmall cylinders observed experimentally by Liu {\em et.al.}(Science 294, 2332 (2001)). Where Tc0T_c\to 0, there is a quantum critical point, and a large fluctuation conductivity is observed in the proximate metallic phase over a wide range of TT and flux . However, we find that the predicted (Gaussian) fluctuation conductivity in the neighborhood of the quantum critical point is 4 orders of magnitude smaller than observed experimentally. We argue that the breakdown of Anderson's theorem at any non-integer flux leads to a broad fluctuation region reflecting the existence of ``rare regions'' with local superconducting order. We calculate the leading order correction to the conductivity within a simple model of statistically induced Josephson coupled local ordered regions that rationalizes the existing data.

Keywords

Cite

@article{arxiv.cond-mat/0505688,
  title  = {Disorder induced non-Fermi liquid near a metal-superconductor quantum phase transition},
  author = {Oskar Vafek and M. R. Beasley and Steven A. Kivelson},
  journal= {arXiv preprint arXiv:cond-mat/0505688},
  year   = {2007}
}

Comments

4 pages; 1 figure