Macroscopic Aharonov--Bohm Effect in Type-I Superconductors

TL;DR

This paper demonstrates a macroscopic Aharonov--Bohm effect in type-I superconductors, where magnetic flux significantly alters the critical current, causing large resistance changes and switching between normal and superconducting states.

Contribution

It reveals a macroscopic Aharonov--Bohm effect in type-I superconductors, showing flux-induced critical current modulation and resistance switching.

Findings

Magnetic flux can change the second critical current by up to 50%.

Half a flux quantum can switch the cylinder from normal to superconducting.

The effect manifests as large resistance changes in the superconductor.

Abstract

In type-I superconducting cylinders bulk superconductivity is destroyed above the first critical current. Below the second critical current the `type-I mixed state' displays fluctuation superconductivity which contributes to the total current. A magnetic flux on the axis of the cylinder can change the second critical current by as much as 50 percent so that half a flux quantum can switch the cylinder from normal conduction to superconductivity: the Aharonov--Bohm effect manifests itself in macroscopically large resistance changes of the cylinder.