Magneto-Transport in MoS2: Phase Coherence, Spin Orbit Scattering and the Hall Factor

TL;DR

This study investigates the electronic transport properties of n-type MoS2 2D crystals, including phase coherence, spin orbit scattering, and Hall factor, revealing potential for spintronics and electronic applications.

Contribution

First measurement of spin orbit scattering length in MoS2 using weak localization without optical techniques, and detailed characterization of Hall mobility and Hall factor across temperatures.

Findings

Phase coherence length ~50 nm at 400 mK

Spin orbit scattering length estimated at 430 nm

Hall mobility of 311 cm²/Vs at 1 K, decreasing with temperature

Abstract

We have characterized phase coherence length, spin orbit scattering length, and the Hall factor in n-type MoS2 2D crystals via weak localization measurements and Hall-effect measurements. Weak localization measurements reveal a phase coherence length of ~50 nm at T = 400 mK for a few-layer MoS2 film, decreasing as T^-1/2 with increased temperatures. Weak localization measurements also allow us, for the first time without optical techniques, to estimate the spin orbit scattering length to be 430 nm, pointing to the potential of MoS2 for spintronics applications. Via Hall-effect measurements, we observe a low temperature Hall mobility of 311 cm2/Vs at T = 1 K which decreases as a power law with a characteristic exponent {\gamma}=1.5 from 10 K to 60 K. At room temperature, we observe Hall mobility of 24 cm2/Vs. By determining the Hall factor for MoS2 to be 1.35 at T = 1 K and 2.4 at room temperature, we observe drift mobility of 420 cm2/Vs and 56 cm2/Vs at T = 1 K and room temperature, respectively.