Unconventional Charge-to-Spin Conversion in Graphene/ MoTe2 van der Waals Heterostructures

Abstract

Spin-charge interconversion phenomena are important ingredients for the development of post-CMOS spin-based logic and magnetic memory technologies. Device design is often limited, though, by the fact that in most systems conversion occurs only if charge current, spin current, and spin polarization are mutually orthogonal. The authors find that in graphene/MoTe${}_{2}$ van der Waals heterostructures, charge currents injected in any spatial direction contribute to the same particular spin-polarization direction, thanks to a combination of strong spin-orbit proximity effects and broken crystal symmetries. This insight points to efficient spin-current generation and flexible device design.