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

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.