Linear magnetotransport in monolayer MoS$_2$

TL;DR

This paper develops a momentum balance model to analyze magnetotransport in monolayer MoS₂ under strong magnetic and weak electric fields, revealing oscillations, resonances, and effects of impurities and phonons across different conditions.

Contribution

It introduces a comprehensive theoretical framework for magnetotransport in monolayer MoS₂, accounting for impurity scattering, phonon interactions, and substrate effects, with predictions matching experimental phenomena.

Findings

Shubnikov de Haas oscillations with beating patterns observed at low temperature.

Magnetoresistivity can nearly vanish in certain magnetic field ranges due to intervalley disorders.

Magnetophonon resonances emerge at high temperature, influenced by phonon modes and substrate effects.

Abstract

A momentum balance equation is developed to investigate the magnetotransport properties in monolayer molybdenum disulphide when a strong perpendicular magnetic field and a weak in-plane electric field are applied simultaneously. At low temperature, in the presence of intravalley impurity scattering Shubnikov de Haas oscillation shows up accompanying by a beating pattern arising from large spin splitting and its period may halve due to high-order oscillating term at large magnetic field for samples with ultrahigh mobility. In the case of intervalley disorders, there exists a magnetic-field range where the magnetoresistivity almost vanishes. For low-mobility layer, a phase-inversion of oscillating peaks is acquired in accordance with recent experiment. At high temperature when Shubnikov de Haas oscillation is suppressed, the magnetophonon resonances induced by both optical phonons (mainly due to homopolar and Fr\"ohlich modes) and acoustic phonons (mainly due to intravalley transverse and longitudinal acoustic modes) emerge for suspended system with high mobility. For the single layer on a substrate, another resonance due to surface optical phonons may occur, resulting in a complex behavior of the total magnetoresistance. The beating pattern of magnetophonon resonance due to optical phonons can also be observed. However, for nonsuspended layer with low mobility, the magnetoresistance oscillation almost disappears and the resistivity increases with field monotonously.