Closed Abrikosov Vortices in a Superconducting Cylinder

TL;DR

This paper introduces a new class of self-consistent, ring-shaped Abrikosov vortex solutions in type-II superconductors, revealing their formation, stability, and the conditions under which they occur, including a novel link to the fine-structure constant.

Contribution

It presents the first theoretical description of toroidal Abrikosov vortices with localized supercurrents and magnetic fields, expanding understanding of vortex structures in superconductors.

Findings

Existence of self-consistent toroidal vortex solutions

Vortex contraction leads to Cooper pair destruction

Thermodynamic excitation condition involves the fine-structure constant

Abstract

The new type of solutions of the London equation for type-II superconductors is obtained to describe the ring-shaped (toroidal) Abrikosov vortices. The specific feature of these solutions is the self-consistent localization of both the supercurrent and the magnetic field, enabling one to construct compact magnetic structures inside a superconductor. The torus vortex contraction caused by the vortex instability leads to the destruction of the Cooper pairing and the formation of a normal electron stream in the vicinity of the torus axis. The thermodynamic condition for the excitation of a small closed vortex by a bunch of charged particles contains the fine-structure constant as a determining parameter.