Vortex state in a superconducting mesoscopic irregular octagon

Abstract

Our study sample is a superconducting bi-dimensional octagon with different boundary conditions immersed in a magnetic external field [Formula: see text]. The boundary conditions are simulated by considering different values of the de Gennes extrapolation length [Formula: see text] on different surfaces of the sample. Our investigation was carried out by solving the time-dependent Ginzburg–Landau equations. We analyzed the superconducting electron density and the magnetization curves as functions of [Formula: see text] and temperature [Formula: see text] in field-cooling and in zero-field-cooling processes for different values of [Formula: see text] and size of the sample. We found a strong dependence of the critical fields on [Formula: see text] and size of the sample.

Matricials methods applied to the solution of the Ginzburg-Landau equations

“…The TDGL equations are based on the Gibbs free energy expansion as a function of even powers of the order parameter ψ(r, t), wich indicates the local density of the superconducting electrons, with which via the application of the functional derivative with respect to ψ * and to the vector potential A, being the magnetic induction B = ∇ × A, the time-dependent Ginzburg-Landau equations TDGL are obtained, thus described in their dimensionless form for a two-dimensional system (Equation (1) and Equation ( 2)) [6][7][8][9].…”

“…The study of multi-band systems, topological superconductivity, system extensions in the presence of external currents, 1.5 type superconductivity, Skirmions and solitons responsible for non-monotonic interaction between vortices, semi-Meissner effect, responsible for fractional vorticity, are some of the topics of study that have been of great interest in the scientific community in recent years [1][2][3][4][5][6][7][8][9][10][11]. These systems have been studied with great success, using the Ginzburg-Landau model.…”