Spin–orbit coupling induced spin polarized valley states in SrRuO3/BiIrO3 heterostructures

Abstract

The electronic properties of SrRuO₃/BiIrO₃ superlattices are investigated by first-principles calculations with spin–orbit coupling. The results show that the strength of hybridization near the Fermi level is dependent on the distance between the closest transition metal Ru and Ir atoms. We find that both spin and valley polarizations in bilayered BiIrO₃ are achieved in Bi-terminated models. Furthermore, different stacking patterns can modulate the magnitude and sign of valley polarization and switch the p- or n-type doping of bilayered BiIrO₃. Meanwhile, a spin-down polarized valley polarization of 79.5 meV can be induced in bilayered SrRuO₃. The different thicknesses calculated demonstrate that the valley in the SrRuO₃/BiIrO₃ model is limited to the bilayered structure. The tunable valley and spin polarizations in SrRuO₃/BiIrO₃ superlattices would enrich the diversity and boost the development of high-performance spintronic and valleytronic devices.