Hu Cheng, Wu Tongyao, Huang Xinyue, Dong Yulong, Chen Jiajun, Zhang Zhichun, Lyu Bosai, Ma Saiqun, Watanabe Kenji, Taniguchi Takashi, Xie Guibai, Li Xiaojun, Liang Qi, Shi Zhiwen
Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China.
Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan.
Sci Rep. 2022 Jan 7;12(1):204. doi: 10.1038/s41598-021-04030-z.
The electrical and optical properties of twisted bilayer graphene (tBLG) depend sensitively on the twist angle. To study the angle dependent properties of the tBLG, currently it is required fabrication of a large number of samples with systematically varied twist angles. Here, we demonstrate the construction of in-situ twistable bilayer graphene, in which the twist angle of the two graphene monolayers can be in-situ tuned continuously in a large range with high precision. The controlled tuning of the twist angle is confirmed by a combination of real-space and spectroscopic characterizations, including atomic force microscopy (AFM) identification of crystal lattice orientation, scanning near-field optical microscopy (SNOM) imaging of superlattice domain walls, and resonant Raman spectroscopy of the largely enhanced G-mode. The developed in-situ twistable homostructure devices enable systematic investigation of the twist angle effects in a single device, thus could largely advance the research of twistronics.
扭曲双层石墨烯（tBLG）的电学和光学性质敏感地依赖于扭曲角。为了研究tBLG的角度依赖性性质，目前需要制备大量具有系统变化扭曲角的样品。在此，我们展示了原位可扭曲双层石墨烯的构建，其中两个石墨烯单层的扭曲角可以在大范围内以高精度连续地原位调节。通过实空间和光谱表征的组合，包括晶格取向的原子力显微镜（AFM）识别、超晶格畴壁的扫描近场光学显微镜（SNOM）成像以及大幅增强的G模式的共振拉曼光谱，证实了扭曲角的可控调节。所开发的原位可扭曲同质结构器件能够在单个器件中系统地研究扭曲角效应，从而可极大地推动扭曲电子学的研究。
