Spin-Orbit mediated spin relaxation in monolayer MoS2

TL;DR

This paper investigates the mechanisms of spin relaxation in monolayer MoS2, focusing on intra-valley spin-orbit interactions, and finds that out-of-plane spin relaxation is inefficient, resulting in long spin lifetimes.

Contribution

It provides a theoretical analysis of spin relaxation in monolayer MoS2 considering intrinsic and Rashba-like spin-orbit effects, aligning with experimental observations.

Findings

Out-of-plane spin relaxation is inefficient in hole-doped MoS2.

Spin lifetimes exceed nanoseconds, consistent with experiments.

Intrinsic spin splitting stabilizes out-of-plane spin polarization.

Abstract

We study the intra-valley spin-orbit mediated spin relaxation in monolayers of MoS2 within a two bands effective Hamiltonian. The intrinsic spin splitting of the valence band as well as a Rashba-like coupling due to the breaking of the out-of-plane inversion symmetry are considered. We show that, in the hole doped regime, the out-of-plane spin relaxation is not very efficient since the spin splitting of the valence band tends to stabilize the spin polarization in this direction. We obtain spin lifetimes larger than nanoseconds, in agreement with recent valley polarization experiments.