Observation and manipulation of valley polarization in two-dimensional H-Tl2O/CrI3 heterostructure

Abstract We report the two-dimensional (2D) H-Tl2O/CrI3 van der Waals (vdW) heterostructure as a promising valleytronics materials, and investigate the manipulation of valley polarization and valley spin splitting of it by using the first principle calculations. The H-Tl2O/CrI3 heterostructure displays the valley polarization in both the conduction and valence band at two valleys. Especially, the valley polarization can be reached to 14.95 meV at the conduction band. Also, a large valley spin splitting of 0.57 (0.58) eV at the K (K') points are shown in the conduction band. With the manipulation of the interlayer spacing and the in-plane biaxial strain, both the valley polarization and the valley spin splitting for the H-Tl2O/CrI3 heterostructure follow the short-range effects of interfacial orbital hybridization, thus a nearly linear relationship is shown. Our work not only provides the application prospects of the H-Tl2O/CrI3 heterostructure nanodevices, but also gives theoretical effective support for further development of valleytronics.