Hall conductivity dominated by fluctuations near the superconducting transition in disordered thin films

Abstract

We have studied the Hall effect in superconducting tantalum nitride films. We find a large contribution to the Hall conductivity near the superconducting transition, which we can track to temperatures well above T[subscript c] and magnetic fields well above the upper critical field H[subscript c2](0). This contribution arises from Aslamazov-Larkin superconducting fluctuations, and we find quantitative agreement between our data and recent theoretical analysis based on time-dependent Ginzburg-Landau theory.