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.