Distinctive Electronic and Spin Properties Driven by Strong Interlayer Hybridization in the α-Tellurene/GaTe Bilayer

Both theoretical and experimental studies have confirmed that combining two or more two-dimensional (2D) monolayer materials into heterostructures is an efficient way to tailor the physical properties of single 2D materials. In this paper, we design a 2D bilayer α-tellurene/GaTe (Te/GaTe) van der Waals heterostructure (vdWH) with an extremely strong interlayer hybridization, a distinctive electronic, spin and optical properties using first-principles calculations. Our calculated results show that the Te/GaTe vdWH is an intrinsic type-I vdWH with an indirect band gap of 0.65 eV, presenting a unique optical property and a high carrier mobility up to 10³ cm²/V/s. Intriguingly, in the Te/GaTe vdWH, the strong interlayer hybridization together with the broken symmetry drives the significant spin effect, especially the Rashba effect with a Rashba constant of 0.75 eV Å. Meanwhile, the strong hybridization also makes the electronic property and heterostructure type susceptible to strain and an electric field. Our findings provide a novel 2D Te/GaTe semiconductor vdWH that can be used in electronics and spintronics.