Gapless inhomogeneous superfluid phase with spin-dependent disorder

Abstract

We show that the presence of a spin-dependent random potential in a superconductor or a superfluid atomic gas leads to distinct transitions at which the energy gap and average order parameter vanish, generating an intermediate gapless superfluid phase, in marked contrast to the case of spin-symmetric randomness where no such gapless superfluid phase is seen. By allowing the pairing amplitude to become inhomogeneous, the gapless superconducting phase persists to considerably higher disorder compared with the prediction of Abrikosov-Gorkov. The low-lying excited states are located predominantly in regions where the pairing amplitude vanishes and coexist with the superfluid regions with a finite pairing. Our results are based on inhomogeneous Bogoliubov-de Gennes mean field theory for a two dimensional attractive Hubbard model with spin-dependent disorder.

6 pages, 5 figures

References in corpus (4)

• Strongly interacting bosons in a disordered optical lattice
• Phase Diagram of Commensurate Two-Dimensional Disordered Bose Hubbard Model
• Exotic paired states with anisotropic spin-dependent Fermi surfaces
• Island formation in disordered superconducting thin films at finite magnetic fields

Cited by in corpus (5)

• Fate of disorder-induced inhomogeneities in strongly correlated d-wave superconductors
• Anderson Localization in Degenerate Spin-Orbit Coupled Fermi Gases with Disorder
• Gapless superconductivity and its real-space topology in quasicrystals
• Interaction-Induced Gradients Across a Confined Fermion Lattice
• Influence of structural disorder and Coulomb interactions in the superconductor-insulator transition applied to boron doped diamond