THE THIRD CRITICAL FIELD (HC3) OF SINGLE-CRYSTALLINE K0.73Fe1.68Se2 BY GINZBURG-LANDAU APPROACH

Abstract

In this paper, two-band Ginzburg-Landau (GL) equations for magnetic superconductors were solved analytically to determine the temperature dependence of surface critical magnetic field (Hc3). By variation method analytically from 1st GL equations and modified to the Changjan & Udomsamuthirun’s temperature dependence model. We found that, our model could find a good agreement with the experimental data of single-crystalline K0.73Fe1.68Se2 superconductors vicinity the critical temperature scenery and the ratio Hc3/Hc2 (where Hc2 is the upper critical field of single-crystalline K0.73Fe1.68Se2) indicated powerful temperature dependence.