Two-Band Calculations on the Superconducting Property of SrPt2As2

Recently, electronic specific heat experiments suggest that SrPt 2 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 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 Fe 3 Si 5 , both the upper critical field and the reduced critical velocity of Cooper pairs increase as the angle increases.