Electron/infrared-phonon coupling in ABC trilayer graphene
Xiaozhou Zan, Xiangdong Guo, Aolin Deng, Zhiheng Huang, Le Liu, Fanfan Wu, Yalong Yuan, Jiaojiao Zhao, Yalin Peng, Li Lü, Yangkun Zhang, Xiuzhen Li, Jundong Zhu, Jinwei Dong, Dongxia Shi, Wei Yang, Xiaoxia Yang, Zhiwen Shi, Luojun Du, Qing Dai, Guangyu Zhang
Abstract
Stacking order plays a crucial role in determining the crystal symmetry and has significant impacts on electronic, optical, magnetic, and topological properties. Electron-phonon coupling, which is central to a wide range of intriguing quantum phenomena, is expected to be intricately connected with stacking order. Understanding the stacking order-dependent electron-phonon coupling is essential for understanding peculiar physical phenomena associated with electron-phonon coupling, such as superconductivity and charge density waves. In this study, we investigate the effect of stacking order on electron-infrared phonon coupling in graphene trilayers. By using gate-tunable Raman spectroscopy and excitation frequency-dependent near-field infrared nanoscopy, we show that rhombohedral ABC-stacked trilayer graphene has a significant electron-infrared phonon coupling strength. Our findings provide novel insights into the superconductivity and other fundamental physical properties of rhombohedral ABC-stacked trilayer graphene, and can enable nondestructive and high-throughput imaging of trilayer graphene stacking order using Raman scattering.