Rashba states localized to InSe layer in InSe/GaTe(InTe) heterostructure

Abstract

The zero potential gradient in 2D III-VI chalcogenides NX (N = Ga, In; X = S, Se, Te) monolayers hinders the Rashba spin splitting (RSS), which limits their application in spintronics. Here, we construct InSe/GaTe and InSe/InTe van der Waals (vdW) heterostructures and investigate their Rashba SOC effect on the basis of first-principles calculations. The occurrence of internal electric field in the heterostructures induces spin splitting conduction band minimum (CBM). Rashba characteristic of the spin splitting can be confirmed through the band structures and spin textures. The projected energy bands suggest that the RSS state in both heterostructures mainly roots in InSe layers. Furthermore, in-plane strain, vertical strain, and the external electric field are all proved to be effective methods to regulate the RSS. When an in-plane strain of 6% is exerted, the Rashba coefficient can become as high as 1.33 eV Å and 1.26 eV Å for InSe/GaTe and InSe/InTe, respectively. The occurrence of controllable RSS at CBM makes the both heterostructures become potential candidate materials for spintronic devices.