Intermediate State in Type I superconducting sphere: pinning and size effect

TL;DR

This paper uses simulations based on Ginzburg-Landau equations to study how sphere size and pinning centers influence the intermediate state in Type I superconductors, revealing transformations and turbulence phenomena.

Contribution

It provides new insights into the effects of size and pinning centers on the intermediate state in Type I superconducting spheres through detailed simulations.

Findings

Small clean spheres exhibit one-domain states.

Large spheres develop multi-domain structures.

Dirty spheres show turbulence in the intermediate state.

Abstract

Simulations, based on the time dependent Ginzburg-Landau equations, show that the magnetization and spatial structure of the intermediate state strongly affected both by the radius of the sphere and by pinning center concentration. The intermediate states undergoes transformation from one-domain state in small clean sphere to multi-domain structure in big spheres. In spheres where part of the superconducting material replaced by the 0.5% randomly distributed normal phase (dirty case) the intermediate state demonstrates a well pronounced turbulence behavior.