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We present results of measurements obtained from a mesoscopic ring of a highly disordered superconductor. Superimposed on a smooth magnetoresistance background we find periodic oscillations with a period that is independent of the strength of the magnetic field. The period of the oscillations is consistent with charge transport by Cooper pairs. The oscillations persist unabated for more than 90 periods, through the transition to the insulating phase, up to our highest field of 12 T. [ABSTRACT FROM AUTHOR]

Near the superconducting phase transition, fluctuations significantly modify the electronic transport properties. Here we study the fluctuation corrections to the Hall conductivity in disordered films, extending previous derivations to a broader range of temperatures and magnetic fields, including the vicinity of the magnetic field induced quantum critical point. In the process, we found a new contribution to the Hall conductivity that was not considered before. Recently, our theory has been used to fit measurements of the Hall resistance in amorphous TaN films. [ABSTRACT FROM AUTHOR]

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 Tc and magnetic fields well above the upper critical field Hc2(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. [ABSTRACT FROM AUTHOR]