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arXiv · 2202.10088

Optical signature of cascade transitions between moir\'e interlayer excitons

Qinghai Tan·Abdullah Rasmita·Zhaowei Zhang·K. S. Novoselov·Wei-bo Gao
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Abstract

Cascade transition between energy levels has important applications, such as in quantum information protocols and quantum cascade lasers. In two-dimensional heterostructure, the moir\'e superlattice potential can result in multiple interlayer exciton (IX) energy levels. We demonstrate the cascade transitions between such moir\'e IXs by performing time- and energy-resolved photoluminescence measurements. We show that the lower-energy moir\'e IX can be excited to higher-energy ones, facilitating IX population inversion.

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Qinghai Tan, Abdullah Rasmita, Zhaowei Zhang, K. S. Novoselov, Wei-bo Gao. 2022-02-21. Optical signature of cascade transitions between moir\'e interlayer excitons. https://doi.org/10.1103/physrevlett.129.247401

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