Pressure engineering of the excitonic moiré-potential landscape and exciton-charge interplay in semiconductor moiré superlattices

Wenbing Li; Tianhao Yue; Wenjian Su; Zhexu Shan; Chen Xu; Jichen Zhou; Kenji Watanabe; Takashi Taniguchi; Liguo Ma; Yuanfeng Xu; Shiyao Zhu; Yang Gao; Yanhao Tang

arXiv · 2610.19542

Pressure engineering of the excitonic moiré-potential landscape and exciton-charge interplay in semiconductor moiré superlattices

Wenbing Li·Tianhao Yue·Wenjian Su·Zhexu Shan·Chen Xu·Jichen Zhou·Kenji Watanabe·Takashi Taniguchi·Liguo Ma·Yuanfeng Xu·Shiyao Zhu·Yang Gao·Yanhao Tang

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Abstract

Semiconductor moiré superlattices, owing to strongly bound excitons and pronounced electronic correlation, have emerged as an intriguing solid platform for exploring correlated bosonic phenomena, where the moiré potential landscape plays a central role. Hydrostatic pressure allows continuous, in-situ tuning of this landscape, but remains underexplored because of experimental challenges. Here we integrate a diamond anvil pressure cell with high quality dual gated WSe2/WS2 twisted bilayers and perform cryogenic optical spectroscopy. We observe distinct pressure evolutions of moiré intralayer excitons, which reveal drastic modulation of the excitonic moiré-potential landscape captured by a continuum model and suggest the capability of engineering the exciton-band topology. Moreover, we demonstrate efficient pressure control over the interplay between charges and both intralayer and interlayer excitons: the intralayer charge-transfer exciton becomes less sensitive to doping, likely due to reduced charge-transfer character; in contrast, the interlayer exciton exhibits enhanced exciton-charge repulsion. Our results establish hydrostatic pressure as a powerful tuning knob for engineering bosonic quasiparticles and Bose-Fermi interactions in moiré materials.

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Wenbing Li, Tianhao Yue, Wenjian Su, Zhexu Shan, Chen Xu, Jichen Zhou, Kenji Watanabe, Takashi Taniguchi, Liguo Ma, Yuanfeng Xu, Shiyao Zhu, Yang Gao, Yanhao Tang. 2026-10-14. Pressure engineering of the excitonic moiré-potential landscape and exciton-charge interplay in semiconductor moiré superlattices. https://arxiv.org/abs/2610.19542

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