Two-Band Calculations on the Superconducting Property of SrPt $$_{2}\mathrm{As}_{2}$$ 2 As 2

Abstract

Recently, electronic specific heat experiments suggest that SrPt\(_{2}\mathrm{As}_{2}\) has two superconducting energy gaps. We have therefore investigated the temperature and angular dependence of the upper critical field and the critical velocity of Cooper pairs for superconductor SrPt\(_{2}\mathrm{As}_{2}\) based on the two-band Ginzburg–Landau theory. The theoretical result for the temperature dependence of the upper critical field fits the experimental data very well over a broad temperature range. Contrary to the two-band superconductor Lu\(_{2}\mathrm{Fe}_{3}\mathrm{Si}_{5}\), both the upper critical field and the reduced critical velocity of Cooper pairs increase as the angle increases.