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arXiv · 2601.15631

Anomalous valley Hall dynamics of exciton-polaritons

Xingzhou Chen·Yuanjun Guan·Areg Ghazaryan·Shiran Sun·Lingxiao Yu·Ruitao Lv·Artem Volosniev·Zheng Sun·Jian Wu
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Abstract

The valley degree of freedom in atomically thin transition-metal dichalcogenides provides a natural binary index for information processing. Exciton-polaritons formed under strong light-matter coupling offer a promising route to overcome the limited lifetime and transport of bare valley excitons. Here we report an anomalous optical valley Hall effect in a monolayer WS2 exciton-polariton system. Using polarization- and time-resolved real-space imaging, we directly visualize a symmetry-breaking spatial separation of polaritons from opposite valleys under linearly polarized excitation, accompanied by an ultrafast Hall drift velocity on the order of 10^5 m/s. This behaviour cannot be accounted for by conventional cavity-induced mechanisms and instead points to a strain-induced synthetic pseudomagnetic field acting on the excitonic component of polaritons. Our results establish exciton-polaritons as a high-speed and optically accessible platform for valley transport, opening pathways towards tunable valleytronic and topological photonic devices.

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Xingzhou Chen, Yuanjun Guan, Areg Ghazaryan, Shiran Sun, Lingxiao Yu, Ruitao Lv, Artem Volosniev, Zheng Sun, Jian Wu. 2026-01-22. Anomalous valley Hall dynamics of exciton-polaritons. https://arxiv.org/abs/2601.15631

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