Giant vortex states in type I superconductors simulated by Ginzburg-Landau equations

TL;DR

This study uses numerical solutions of Ginzburg-Landau equations to explore giant vortex states in type I superconductors, revealing size dependence on film thickness and the influence of geometry on vortex stabilization.

Contribution

It provides a systematic numerical analysis of vortex structures in type I superconductors, highlighting the effects of film thickness and sample geometry.

Findings

Giant vortices increase in size as film thickness decreases.

Giant vortices appear at intermediate thicknesses without forming a lattice.

Single vortices are stabilized by geometry in the thinnest films.

Abstract

The quantization of magnetic flux in superconductors is usually seen as vortices penetrating the sample. While vortices are unstable in bulk type I superconductors, restricting the superconductor causes a variety of vortex structures to appear. We present a systematic study of giant vortex states in type I superconductors obtained by numerically solving the Ginzburg-Landau equations. The size of the vortices is seen to increase with decreasing film thickness. In type I superconductors, giant vortices appear at intermediate thicknesses but they do not form a well-defined vortex lattice. In the thinnest type I films, singly quantized vortices seem to be stabilized by the geometry of the sample instead of an increase in the effective Ginzburg-Landau parameter.