Superconducting properties of the In-substituted topological crystalline insulator, SnTe

We report detailed investigations of the properties of a superconductor obtained by substituting In at the Sn site in the topological crystalline insulator (TCI), SnTe. Transport, magnetization and heat capacity measurements have been performed on crystals of Sn$_{0.6}$In$_{0.4}$Te, which is shown to be a bulk superconductor with $T_c^{\rm{onset}}$ at $\sim4.70(5)$~K and $T_c^{\rm{zero}}$ at $\sim3.50(5)$~K. The upper and lower critical fields are estimated to be $\mu_0H_{c2}(0)=1.42(3)$~T and $\mu_0H_{c1}(0)=0.90(3)$~mT respectively, while $\kappa=56.4(8)$ indicates this material is a strongly type II superconductor