Possible enhancement of superconductivity by Sb doping in rare earth doped 112 compounds: an ab-initio study

Abstract

ABSTRACT We present electronic structure calculations of rare earth doped Ca1− x R x FeAs2, 112 Fe-based high temperature superconducting materials with special emphasis on Sb doping at the chain As-site. The electronic structures obtained within Density functional Theory based first principles calculations on 112 compounds with Sb doping for different rare earth (Pr, Nd, Sm) co-doping reveal a significant increase in partial density of states of As at the Fermi level. An increase in density of states at the Fermi level indicates increased availability of electrons for Cooper pairing and hence possible enhancement of superconductivity. Our results indicate possible preference of Sm doping over other rare earth elements as far as enhancement of superconductivity via Sb doping at As-chain is concerned.