University of Wollongong Research Online Australian Institute for Innovative Materials - Papers Australian Institute for Innovative Materials 2017 Cooperative Electron-Phonon Coupling and Buckled Structure in Germanene on Au(111) Jincheng Zhuang University of Wollongong,
[email protected] Nan Guo Dalian University of Technology Zhi Li University of Wollongong,
[email protected] Xun Xu University of Wollongong,
[email protected] Jiaou Wang Chinese Academy of Sciences See next page for additional authors Publication Details Zhuang, J., Guo, N., Li, Z., Xu, X., Wang, J., Zhao, J., Dou, S. Xue. & Du, Y. (2017). Cooperative Electron-Phonon Coupling and Buckled Structure in Germanene on Au(111). ACS Nano, 11 (4), 3553-3559. Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library:
[email protected] Cooperative Electron-Phonon Coupling and Buckled Structure in Germanene on Au(111) Abstract Germanene, a single-atom-thick germanium nanosheet in a honeycomb lattice, was proposed to be a Dirac fermion material beyond graphene. We performed scanning tunneling microscopy and in situ Raman spectroscopy studies combined with first-principles calculations on the atomic structures and the electronic and phonon properties of germanene on Au(111). The low-buckled 1 x 1 germanene honeycomb lattice was determined to exist in an unexpected rectangular √7 x √7 superstructure. Through in situ Raman measurements, distinctive vibrational phonon modes were discovered in √7 x √7 germanene, revealing the special coupling between the Dirac fermion and lattice vibrations, namely, electron-phonon coupling (EPC). The significant enhancement of EPC is correlated with the tensile strain, which is evoked by the singular buckled structure of √7 x √7 germanene on the Au(111) substrate.