Flux-Induced Vortex in Mesoscopic Superconducting Loops

TL;DR

This paper predicts a novel flux-induced quantum vortex in asymmetric mesoscopic superconducting loops, differing from traditional vortices, with potential experimental verification methods.

Contribution

It introduces the concept of a flux-induced vortex in asymmetric superconducting loops, expanding understanding of vortex behavior in mesoscopic systems.

Findings

Vortices can form along lines where the order parameter vanishes in asymmetric samples.

The vortex position depends on the magnetic flux and symmetry of the sample.

Proposed experimental methods to detect these flux-induced vortices.

Abstract

We predict the existence of a quantum vortex for an unusual situation. We study the order parameter in doubly connected superconducting samples embedded in a uniform magnetic field. For samples with perfect cylindrical symmetry, the order parameter has been known for long and no vortices are present in the linear regime. However, if the sample is not symmetric, there exist ranges of the field for which the order parameter vanishes along a line, parallel to the field. In many respects, the behavior of this line is qualitatively different from that of the vortices encountered in type II superconductivity. For samples with mirror symmetry, this flux-induced vortex appears at the thin side for small fluxes and at the opposite side for large fluxes. We propose direct and indirect experimental methods which could test our predictions.