Optically induced spin Hall current in monolayer Janus NbSSe: a first-principles study

Monolayer Janus transition-metal dichalcogenides possess Ising- and Rashba-type spin-orbit-couplings (SOC), leading to intriguing spin splitting effects at K and K', and around Γ points across the wide energy range. Using first-principles calculations, we unveil these SOC characteristics in metallic Janus NbSSe and demonstrate its potential for optically controlled spin current generation. On the basis of the symmetry of the system, we show that different linear polarized light can selectively drive spin currents of distinct spin components. Our findings establish NbSSe as a promising candidate for next-generation optospintronic technologies, which is offering a pathway toward the development of polarization-tunable spin-current sources.