Mesoscopic Superconducting Disc with Short-Range Columnar Defects

TL;DR

This paper investigates how short-range columnar defects affect the magnetic properties and vortex behavior in mesoscopic superconducting discs, revealing defect-induced vortex arrangements and magnetization features.

Contribution

It provides new insights into vortex dynamics and magnetization changes caused by short-range defects in mesoscopic superconductors.

Findings

Defects facilitate vortex penetration and reduce magnetization.

Weak defects split giant vortex states into multiple vortices.

Strong defects trap vortices, causing magnetization jumps.

Abstract

Short-range columnar defects essentially influence the magnetic properties of a mesoscopic superconducting disc.They help the penetration of vortices into the sample, thereby decrease the sample magnetization and reduce the upper critical field. Even the presence of weak defects split a giant vortex state (usually appearing in a clean disc in the vicinity of the transition to a normal state) into a number of vortices with smaller topological charges. In a disc with a sufficient number of strong enough defects vortices are always placed onto defects. The presence of defects lead to the appearance of additional magnetization jumps related to the redistribution of vortices which are already present on the defects and not to the penetration of new vortices.