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arXiv · 2302.13003

Interlayer donor-acceptor pair excitons in MoSe2/WSe2 moir\'e heterobilayer

Hongbing Cai·Abdullah Rasmita·Qinghai Tan·Jia-Min Lai·Ruihua He·Disheng Chen·Naizhou Wang·Zhao Mu·Zumeng Huang·Zhaowei Zhang·John J. H. Eng·Yuanda Liu·Yongzhi She·Nan Pan·Xiaoping Wang·Xiaogang Liu·Jun Zhang·Weibo Gao
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Abstract

Localized interlayer excitons (LIXs) in two-dimensional moir\'e superlattices exhibit sharp and dense emission peaks, making them promising as highly tunable single-photon sources. However, the fundamental nature of these LIXs is still elusive. Here, we show the donor-acceptor pair (DAP) mechanism as one of the origins of these excitonic peaks. Numerical simulation results of the DAP model agree with the experimental photoluminescence spectra of LIX in the moir\'e MoSe2/WSe2 heterobilayer. In particular, we find that the emission energy-lifetime correlation and the nonmonotonic power dependence of the lifetime agree well with the DAP IX model. Our results provide insight into the physical mechanism of LIX formation in moir\'e heterostructures and pave new directions for engineering interlayer exciton properties in moir\'e superlattices.

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Hongbing Cai, Abdullah Rasmita, Qinghai Tan, Jia-Min Lai, Ruihua He, Disheng Chen, Naizhou Wang, Zhao Mu, Zumeng Huang, Zhaowei Zhang, John J. H. Eng, Yuanda Liu, Yongzhi She, Nan Pan, Xiaoping Wang, Xiaogang Liu, Jun Zhang, Weibo Gao. 2023-02-25. Interlayer donor-acceptor pair excitons in MoSe2/WSe2 moir\'e heterobilayer. https://doi.org/10.1038/s41467-023-41330-6

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