Anisotropic refraction and valley-spin-dependent anomalous Klein tunneling in an 1T′-MoS2-based p-n junction

We investigate the transport properties of electron in an 1T′-MoS2-based p-n junction. The anisotropic refraction of electron is found when the electron beam crosses the p-n junction, which brings the phenomenon of valley splitting without any external fields. Besides, the valley-spin-dependent anomalous Klein tunneling, i.e., the perfect transmission exists at a nonzero incident angle of valley-spin-dependent electron, happens when the vertical electric field is equal to the critical electric field. These two peculiar properties arise from the same reason that the tilted band structure makes the directions of wavevector and velocity different. Our work designs a special valley splitter without any external fields and finds a new type of Klein tunneling.