Quantum transport and observation of Dyakonov-Perel spin-orbit scattering in monolayer MoS$_2$

TL;DR

This paper reports the experimental observation of a crossover from weak localization to weak anti-localization in monolayer MoS2, revealing spin relaxation via the Dyakonov-Perel mechanism and its dependence on momentum relaxation.

Contribution

It provides the first experimental evidence of Dyakonov-Perel spin-orbit scattering in monolayer MoS2 and links spin lifetime to quantum transport behavior.

Findings

Observation of weak localization to anti-localization crossover

Spin lifetime inversely proportional to momentum relaxation time

Evidence of Dyakonov-Perel spin relaxation mechanism

Abstract

Monolayers of group 6 transition metal dichalcogenides are promising candidates for future spin-, valley-, and charge-based applications. Quantum transport in these materials reflects a complex interplay between real spin and pseudo-spin (valley) relaxation processes, which leads to either positive or negative quantum correction to the classical conductivity. Here we report experimental observation of a crossover from weak localization to weak anti-localization in highly n-doped monolayer MoS2. We show that the crossover can be explained by a single parameter associated with electron spin lifetime of the system. We find that the spin lifetime is inversely proportional to momentum relaxation time, indicating that spin relaxation occurs via Dyakonov-Perel mechanism.