Confinement effects on intermediate state flux patterns in mesoscopic type-I superconductors

TL;DR

This paper explores how confinement influences intermediate state flux patterns in mesoscopic type-I superconductors, revealing new vortex phases and domain structures affected by sample geometry.

Contribution

It introduces the formation of vortex phases and normal rings in mesoscopic type-I superconductors, expanding understanding of flux structures under confinement.

Findings

Strong confinement induces vortex phases typical of type-II superconductors.

Normal domain rings are stable at equilibrium in mesoscopic samples.

Sample geometry significantly affects flux structure stability and formation.

Abstract

Intermediate state (IS) flux structures in mesoscopic type-I superconductors are investigated within the Ginzburg-Landau theory. In addition to well-established tubular and laminar structures, the strong confinement leads to the formation of (i) a phase of singly quantized vortices, which is typical for type-II superconductors and (ii) a ring of a normal domain at equilibrium. The stability region and the formation process of these IS flux structures are strongly influenced by the geometry of the sample.