# Highly tunable nonlinear Hall effects induced by spin-orbit couplings in strained polar transition-metal dichalcogenides

## TL;DR

This paper demonstrates that strained polar transition-metal dichalcogenides exhibit strong, tunable nonlinear Hall effects driven by Berry-curvature dipoles associated with spin, offering potential for energy-harvesting devices.

## Contribution

It reveals that spin-induced Berry-curvature dipoles in strained polar TMDs produce significant nonlinear Hall effects that can be electrically and mechanically tuned.

## Key findings

- Strong nonlinear Hall signals in electron-doped polar TMDs under uniaxial strain.
- The nonlinear Hall current magnitude and sign are tunable by electric gating and strain.
- Potential application in electrically switchable energy-harvesting rectifiers.

## Abstract

Recently, signatures of nonlinear Hall effects induced by Berry-curvature dipoles have been found in atomically thin 1T'/Td-WTe$_2$. In this work, we show that in strained polar transition-metal dichalcogenides(TMDs) with 2H-structures, Berry-curvature dipoles created by spin degrees of freedom lead to strong nonlinear Hall effects. Under an easily accessible uniaxial strain of order 0.2%, strong nonlinear Hall signals, characterized by a Berry-curvature dipole on the order of 1{\AA}, arise in electron-doped polar TMDs such as MoSSe, and this is easily detectable experimentally. Moreover, the magnitude and sign of the nonlinear Hall current can be easily tuned by electric gating and strain. These properties can be used to distinguish nonlinear Hall effects from classical mechanisms such as ratchet effects. Importantly, our system provides a potential scheme for building electrically switchable energy-harvesting rectifiers.