Microscopic free energy functional of superconductive amplitude and phase: Superfluid density in disordered superconductors

Abstract

Recent experiments on disordered superconductors find that the superfluid density $n_s(T)$ decreases dramatically and characteristically with disorder, differently from what is expected for a mean order parameter field or BCS, amplitude only, picture for the superconductor. We describe here a new microscopic free energy functional which explicitly describes its dependence on both the amplitude and phase of superconducting order, in a gauge invariant manner. We use this here in an approximation of noninteracting phase fluctuations (Gaussian or harmonic approximation) to obtain $n_s(T)$ in the presence of (static) disorder. We compare our results successfully with experiment.

4 figures; published version; change of the title

References in corpus (1)

• Phase fluctuations in a strongly disordered s-wave superconductor close to the metal-insulator transition

Cited by in corpus (4)

• Superfluid Density in Conventional Superconductors: From Clean to Strongly Disordered
• Universal scaling relations in electron-phonon superconductors
• Dependence of the critical temperature and disorder in holographic superconductors on superfluid density
• Inhomogeneous phase stiffness in two-dimensional $s$-wave disordered superconductors