Cavity quantum electrodynamics with moiré photonic crystal nanocavity

Sai Yan; Hancong Li; Jingnan Yang; Xiqing Chen; Hanqing Liu; Deyan Dai; Rui Zhu; Zhikai Ma; Shushu Shi; Longlong Yang; Yu Yuan; Wenshuo Dai; Danjie Dai; Bowen Fu; Zhanchun Zuo; Haiqiao Ni; Zhichuan Niu; Can Wang; Kuijuan Jin; Qihuang Gong; Xiulai Xu

doi:10.1038/s41467-025-59942-5

Cavity quantum electrodynamics with moiré photonic crystal nanocavity

Nat Commun. 2025 May 19;16(1):4634. doi: 10.1038/s41467-025-59942-5.

Authors

Sai Yan^{1

2}, Hancong Li³, Jingnan Yang³, Xiqing Chen³, Hanqing Liu⁴, Deyan Dai⁴, Rui Zhu^{1

2}, Zhikai Ma³, Shushu Shi^{1

2}, Longlong Yang³, Yu Yuan^{1

2}, Wenshuo Dai³, Danjie Dai^{1

2}, Bowen Fu³, Zhanchun Zuo^{1

2}, Haiqiao Ni⁴, Zhichuan Niu⁴, Can Wang^{5

6

7}, Kuijuan Jin^{1

2

8}, Qihuang Gong³, Xiulai Xu^{9

10

11}

Affiliations

¹ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
² School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China.
³ State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, China.
⁴ State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China.
⁵ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China. canwang@iphy.ac.cn.
⁶ School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China. canwang@iphy.ac.cn.
⁷ Songshan Lake Materials Laboratory, Dongguan, Guangdong, China. canwang@iphy.ac.cn.
⁸ Songshan Lake Materials Laboratory, Dongguan, Guangdong, China.
⁹ State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, China. xlxu@pku.edu.cn.
¹⁰ Peking University Yangtze Delta Institute of Optoelectronics, Nantong, Jiangsu, China. xlxu@pku.edu.cn.
¹¹ Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, China. xlxu@pku.edu.cn.

Abstract

Due to the existence of flatbands within the band structure, twisting photonics introduces a possibility to enhance the interaction between excitons in single QDs and cavity photons because of the extremely high quality factor (Q) in theory. In this work, we report a Purcell effect between single QDs and moiré photonic crystal nanocavities. The moiré photonic crystal nanocavities in a GaAs slab with QDs embedded are formed by twisting two layer photonic crystal structures with specific angles. High Q, low mode volume and large overlap between QDs and cavity mode field have been achieved by optimizing the filling ratio of the single-layer photonic crystal, with which a Q of fundamental modes about 2000 is experimentally demonstrated. A photoluminescence intensity enhancement of a factor about 8.4 is observed when a single QD is in resonance with a cavity mode, with a Purcell factor of about 3.0 confirmed through the lifetime measurement. This result shows the potential of moiré photonics to implement solid-state cavity quantum electrodynamics for future optical quantum information processing.