Superconductivity in Rh17S15 and Pd 17Se15: A comparative study

Abstract

The presence of strongly correlated superconductivity in Rh 17S15 has been recently established. In this work we estimate normal and superconducting parameters of a single crystal of Rh 17S15 and compare them with those of a polycrystalline sample of Pd17Se15 which is reported here for the first time to be a superconductor below 2.2 K. The presence of superconductivity in two iso-structural (space group Pm3m) compounds provides an opportunity to understand the strongly correlated superconductivity in Rh17S 15. We see that large unit volume of Pd17Se15 and the large separation of Pd-Pd atoms in its structure as compared those in a pure Pd metal lead to the absence of strong correlations in this compound. Finally Pd17Se15 can be characterized as an intermediate type-II superconductor as opposed to the strongly correlated superconductivity in Rh17S15. © 2011 The Physical Society of Japan.