Quantum dynamics of charge transfer trions in a MoSe2 moir ́e superlattice
ORAL
Abstract
We investigate new many-electron excited states in twisted MoSe2 homobilayers in which optical resonances evolve with twist angle and doping. A unique type of "charge-transfer" trions can be observed when gradual changes in atomic alignment between the layers occur. In real space, the optically excited electron-hole pair resides in a different site from the doped hole in a moir ́e supercell. In momentum space, the exciton resides in the K-valley while the hole occupies the Γ-valley. The rich internal structure of this trion resonance arises from the ultra-flatness of the first valence band and the distinct influence of moir ́e potential modulation on holes and excitons. We apply a powerful spectroscopy method, two-dimensional electronic coherent spectroscopy to investigate the distinct quantum dynamics of different types of neutral and charged excitons in this moir ́e superlattice.
*We gratefully acknowledge funding the Department of Energy, Office of Basic Energy Sciences under grant DE-SC0019398 and the Welch Foundation grant F-1662 for sample preparation. Collaborations are enabled by National Science Foundation via DMREF DMR-2118806 and DMR-2118779.
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Presenters
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Xiaohui Liu
- University of Texas at Austin