Little-Parks Oscillations in a Single Ring in the vicinity of the Superconductor-Insulator Transition

TL;DR

This study observes persistent Little-Parks oscillations in a disordered superconducting ring across the superconductor-insulator transition, indicating Cooper pair transport even in the insulating phase.

Contribution

It provides experimental evidence of quantum oscillations in a disordered superconductor near the transition, extending understanding of superconductivity in mesoscopic systems.

Findings

Oscillations with a consistent period are observed.

Oscillations persist beyond the superconducting phase into the insulating phase.

Period matches charge transport by Cooper pairs.

Abstract

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.