English

BCS-BEC crossover in a random external potential

Superconductivity 2009-11-13 v2

Abstract

We investigate the ground state properties of a disordered superfluid Fermi gas across the BCS-BEC (Bose Einstein condensate) crossover. We show that, for weak disorder, both the depletion of the condensate fraction of pairs and the normal fluid density exhibit a nonmonotonic behavior as a function of the interaction parameter 1/kFa1/k_Fa, reaching their minimum value near unitarity. We find that, moving away from the weak coupling BCS regime, Anderson's theorem ceases to apply and the superfluid order parameter is more and more affected by the random potential.

Keywords

Cite

@article{arxiv.0709.2621,
  title  = {BCS-BEC crossover in a random external potential},
  author = {G. Orso},
  journal= {arXiv preprint arXiv:0709.2621},
  year   = {2009}
}

Comments

Revised version, one reference added, Phys. Rev. Lett. in press

R2 v1 2026-06-21T09:18:17.605Z