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arXiv · 2406.02942

Light-induced large and tunable valley-selective Hall effect in a centrosymmetric system

Naoya Arakawa·Kenji Yonemitsu
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Abstract

We propose that a large and tunable valley-selective Hall effect can be realized in a centrosymmetric system via light-induced breaking of inversion and time-reversal symmetries. This is demonstrated in graphene driven by bicircularly polarized light, which consists of a linear combination of left- and right-handed circularly polarized light with different frequencies. We also show that our Hall conductivity is two orders of magnitude larger than the maximum value obtained in noncentrosymmetric systems, and that the main valley can be switched by tuning a phase difference between the left- and right-handed circularly polarized light. Our results will enable us to generate and control the valley-selective Hall effect in centrosymmetric systems.

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Naoya Arakawa, Kenji Yonemitsu. 2024-06-05. Light-induced large and tunable valley-selective Hall effect in a centrosymmetric system. https://doi.org/10.1103/physrevb.109.l241201

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