Cooperative effects of lattice and spin–orbit coupling on the electronic structure of orthorhombic SrIrO3

Abstract

Orthorhombic SrIrO3 subjected to strain shows tunable transport properties. With underlying symmetry remaining invariant, these properties are associated with IrO6 octahedral tilting. Adopting first-principles methods, the effects of crystal field, spin–orbit coupling (SOC), and Coulomb correlations, on comparable interaction length scales, are discussed. While tilting induces a crystal-field splitting and band narrowing, SOC induces a partial splitting of the bands rendering SrIrO3 a semi-metallic ground state. The SOC enhanced hybridization of Ir–O orbitals serves as an explanation as to why the critical Hubbard correlation strength increases with increasing SOC strength in SrIrO3 to induce an insulating phase.