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Updated: Jun 28, 2025
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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
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Atomic-scale visualization of the interlayer Rydberg exciton complex in moiré heterostructures
Meng Zhao1,2, Zhongjie Wang3,4, Lu Liu1,2,5
1State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200438, China.
Nature Communications
|April 22, 2024
Summary
Researchers directly mapped excitonic charge clouds in a YbCl3/graphite heterostructure. This breakthrough allows atomic-scale investigation of excitonic phases and their unique energy configurations.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Excitonic systems exhibit fascinating physics but lack atomic-scale resolution.
- Previous studies relied on global measurements, limiting detailed understanding of excitonic phases.
Purpose of the Study:
- To achieve atomic-scale profiling of ground-state interlayer exciton complexes.
- To investigate the charge cloud structure and energy configurations of excitons.
Main Methods:
- Fabrication of monolayer YbCl3/graphite heterostructures.
- Utilizing scanning tunneling microscopy (STM) for direct imaging.
- Performing theoretical calculations to support experimental findings.
Main Results:
- Directly profiled excitonic in-gap states in the heterostructure.
- Observed oscillating Rydberg nodal structure in out-of-plane charge clouds.
- Determined in-plane arrangements influenced by moiré periodicity.
- Revealed a Rydberg series hierarchy indicating large exciton binding energy.
Conclusions:
- Demonstrated the feasibility of microscopically mapping exciton charge clouds.
- Paved a new path for investigating nanoscale order in exotic correlated phases.
- Highlighted the potential for understanding excitonic physics at the atomic level.
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