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arXiv · 1712.02942

Spin-orbit coupling induced valley Hall effects in transition-metal dichalcogenides

Benjamin T. Zhou·Katsuhisa Taguchi·Yuki Kawaguchi·Yukio Tanaka·K. T. Law
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Abstract

In transition-metal dichalcogenides, electrons in the K-valleys can experience both Ising and Rashba spin-orbit couplings. In this work, we show that the coexistence of Ising and Rashba spin-orbit couplings leads to a special type of valley Hall effect, which we call spin-orbit coupling induced valley Hall effect. Importantly, near the conduction band edge, the valley-dependent Berry curvatures generated by spin-orbit couplings are highly tunable by external gates and dominate over the intrinsic Berry curvatures originating from orbital degrees of freedom under accessible experimental conditions. We show that the spin-orbit coupling induced valley Hall effect is manifested in the gate dependence of the valley Hall conductivity, which can be detected by Kerr effect experiments.

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Benjamin T. Zhou, Katsuhisa Taguchi, Yuki Kawaguchi, Yukio Tanaka, K. T. Law. 2019-03-01. Spin-orbit coupling induced valley Hall effects in transition-metal dichalcogenides. https://doi.org/10.1038/s42005-019-0127-7

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