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Electron/infrared-phonon coupling in ABC trilayer graphene.
Xiaozhou Zan1,2, Xiangdong Guo3,4, Aolin Deng5
1Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China.
Nature Communications
|February 29, 2024
Summary
Stacking order significantly influences graphene trilayer properties. Rhombohedral ABC-stacked graphene exhibits strong electron-phonon coupling, crucial for superconductivity and charge density waves.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Stacking order in layered materials dictates crystal symmetry and influences electronic, optical, magnetic, and topological properties.
- Electron-phonon coupling is fundamental to quantum phenomena like superconductivity and charge density waves.
- The interplay between stacking order and electron-phonon coupling is critical for understanding these phenomena.
Purpose of the Study:
- To investigate the impact of stacking order on electron-infrared phonon coupling in graphene trilayers.
- To elucidate the relationship between stacking configuration and electron-phonon interactions.
Main Methods:
- Utilized gate-tunable Raman spectroscopy.
- Employed excitation frequency-dependent near-field infrared nanoscopy.
Main Results:
- Demonstrated significant electron-infrared phonon coupling in rhombohedral ABC-stacked trilayer graphene.
- Established a correlation between stacking order and electron-phonon coupling strength.
Conclusions:
- The stacking order critically affects electron-phonon coupling in graphene trilayers.
- Findings offer insights into superconductivity and physical properties of ABC-stacked trilayer graphene.
- Raman scattering can be used for non-destructive imaging of trilayer graphene stacking order.
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