Emergent Trion Resonance Driven by Lattice Reconstruction in a Moir\'e Superlattice

Zhida Liu; Haonan Wang; Xiaohui Liu; Yue Ni; Hongtao Yan; Frank Y. Gao; Saba Arash; Hyunsue Kim; Dong Seob Kim; Xiangcheng Liu; Xiaoxiao Yu; Yongxin Zeng; Jiamin Quan; Di Huang; Kenji Watanabe; Takashi Taniguchi; Edoardo Baldini; Keji Lai; Allan H. MacDonald; Chih-Kang Shih; Jamie Warner; Li Yang; Xiaoqin Li

arXiv · 2407.17025

Emergent Trion Resonance Driven by Lattice Reconstruction in a Moir\'e Superlattice

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Abstract

We investigate how many-electron excited states emerge in twisted MoSe2 homobilayers when the lattice reconstructions evolve. Notably, we identify a new trion resonance that arises in the transition regime of lattice reconstruction, where gradual changes in atomic alignment between the layers occur. Magnetic field-dependent measurements, supported by first-principles calculations, indicate that the exciton forms at the K valley while the doped hole resides in the Gamma valley. First-principles calculations further indicate that two nearly degenerate exciton resonances can arise, localized at different sites within the moir\'e supercell. We propose that the new trion resonance is a "charge-transfer" trion, in which the electron-hole pair is spatially separated from the doped hole. The emergence of these complex excited states stems from the distinct moir\'e potentials acting on holes and excitons, resulting in their different spatial distribution within the superlattice.

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Zhida Liu, Haonan Wang, Xiaohui Liu, Yue Ni, Hongtao Yan, Frank Y. Gao, Saba Arash, Hyunsue Kim, Dong Seob Kim, Xiangcheng Liu, Xiaoxiao Yu, Yongxin Zeng, Jiamin Quan, Di Huang, Kenji Watanabe, Takashi Taniguchi, Edoardo Baldini, Keji Lai, Allan H. MacDonald, Chih-Kang Shih, Jamie Warner, Li Yang, Xiaoqin Li. 2024-07-24. Emergent Trion Resonance Driven by Lattice Reconstruction in a Moir\'e Superlattice. https://arxiv.org/abs/2407.17025

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