Atomic-scale visualization of the interlayer Rydberg exciton complex in moiré heterostructures

Meng Zhao; Zhongjie Wang; Lu Liu; Chunzheng Wang; Cheng-Yen Liu; Fang Yang; Hua Wu; Chunlei Gao

doi:10.1038/s41467-024-47770-y

Atomic-scale visualization of the interlayer Rydberg exciton complex in moiré heterostructures

Nat Commun. 2024 Apr 22;15(1):3414. doi: 10.1038/s41467-024-47770-y.

Authors

Meng Zhao^#^{1

2}, Zhongjie Wang^#^{3

4}, Lu Liu^#^{1

2

5}, Chunzheng Wang^{1

2}, Cheng-Yen Liu^{1

2}, Fang Yang^{6

7}, Hua Wu^{8

9

10

11}, Chunlei Gao^{12

13

14

15

16

17

18}

Affiliations

¹ State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200438, China.
² Shanghai Qi Zhi Institute, Shanghai, 200232, China.
³ State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200438, China. zhongjiewang18@fudan.edu.cn.
⁴ Shanghai Qi Zhi Institute, Shanghai, 200232, China. zhongjiewang18@fudan.edu.cn.
⁵ Laboratory for Computational Physical Sciences (MOE), Fudan University, Shanghai, 200438, China.
⁶ Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Songhu Rd. 2005, Shanghai, 200438, China.
⁷ Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China.
⁸ State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200438, China. wuh@fudan.edu.cn.
⁹ Shanghai Qi Zhi Institute, Shanghai, 200232, China. wuh@fudan.edu.cn.
¹⁰ Laboratory for Computational Physical Sciences (MOE), Fudan University, Shanghai, 200438, China. wuh@fudan.edu.cn.
¹¹ Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China. wuh@fudan.edu.cn.
¹² State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200438, China. clgao@fudan.edu.cn.
¹³ Shanghai Qi Zhi Institute, Shanghai, 200232, China. clgao@fudan.edu.cn.
¹⁴ Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Songhu Rd. 2005, Shanghai, 200438, China. clgao@fudan.edu.cn.
¹⁵ Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China. clgao@fudan.edu.cn.
¹⁶ Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China. clgao@fudan.edu.cn.
¹⁷ Shanghai Research Center for Quantum Sciences, Shanghai, 201315, China. clgao@fudan.edu.cn.
¹⁸ Shanghai Branch, Hefei National Laboratory, Shanghai, 201315, China. clgao@fudan.edu.cn.

^# Contributed equally.

Abstract

Excitonic systems, facilitated by optical pumping, electrostatic gating or magnetic field, sustain composite particles with fascinating physics. Although various intriguing excitonic phases have been revealed via global measurements, the atomic-scale accessibility towards excitons has yet to be established. Here, we realize the ground-state interlayer exciton complexes through the intrinsic charge transfer in monolayer YbCl₃/graphite heterostructure. Combining scanning tunneling microscope and theoretical calculations, the excitonic in-gap states are directly profiled. The out-of-plane excitonic charge clouds exhibit oscillating Rydberg nodal structure, while their in-plane arrangements are determined by moiré periodicity. Exploiting the tunneling probe to reflect the shape of charge clouds, we reveal the principal quantum number hierarchy of Rydberg series, which points to an excitonic energy-level configuration with unusually large binding energy. Our results demonstrate the feasibility of mapping out the charge clouds of excitons microscopically and pave a brand-new way to directly investigate the nanoscale order of exotic correlated phases.

Abstract

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