Complex Vortex Configuration in a Disk with a Higher/Lower Critical Temperature Superconducting Geometrical Central Defect

Abstract

The influence of a pentagonal/hexagonal defect at higher/lower critical temperature in a thin superconducting disk on the critical fields and vortex configuration is investigated numerically. The coupled nonlinear Ginzburg–Landau equations are solved self-consistently to calculate and compare quantities such as the magnetization, super-current, free Gibbs energy, Cooper pair density, magnetic induction, and phase of order parameter. For certain magnetic field ranges, we found a coexistence of a giant vortex state, placed in the center of the disk and a complex multi-vortex state, toward the corners of the defect.