Charge-to-spin conversion in twisted <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>graphene</mml:mi><mml:mo>/</mml:mo><mml:msub><mml:mi>WSe</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> heterostructures
Seungjun Lee, D. J. P. de Sousa, Young‐Kyun Kwon, Fernando de Juan, Zhendong Chi, Fèlix Casanova, Tony Low
Abstract
We investigate the twist-angle dependence of spin-orbit coupling proximity effects and charge-to-spin conversion (CSC) in $\mathrm{graphene}/{\text{WSe}}_{2}$ heterostructures from first principles. The CSC is shown to strongly depend on the twist angle, with standard Rashba-Edelstein and disorder-free spin Hall efficiencies optimized near ${30}^{\ensuremath{\circ}}$ twisting. Symmetry breaking due to twisting also gives rise to an unconventional Rashba-Edelstein effect, with electrically generated nonequilibrium spin densities possessing spins collinear to the applied electric field. Our work provides a perspective on the electrical generation of spins in van der Waals heterostructures.