One-Dimensional Spin Channel in Two-Dimensional Transition Metal Dichalcogenide Heterostructures

We show that it is possible to obtain one-dimensional (1D) spin channels at the lateral heterojunction of 2D transition metal dichalcogenides by a current flow without the necessity of any external magnetic field. This originates from the native spin orbit coupling of 2D materials in conjunction with the electric field that develops due to conduction band-offset at the junction. Nonetheless, we show that the underlying physics is very different from the well-known spin Hall effect. We find that the degree of spin polarization could be as high as 0.1% for conduction band transport and 0.75% for valence band transport at room temperature in a lateral heterostructure of typical 2D semiconductors such as MoS
₂
/WSe
₂
. We also find that the spin polarization increases with longitudinal (transport) effective mass due to increased momentum of the flowing electrons. Such 1D spin channels might allow probing of spin dynamics in confined phase spaces in addition to potentially contributing to spintronics applications.