1. State Key Laboratory of Silicon Materials and School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
2. State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
3. Physics Department, The University of Hong Kong, Pokfulam Road, Hong Kong
4. Center for Multidimensional Carbon Materials, Institute for Basic Science, School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea
5. Key Laboratory of Polar Materials and Devices and Department of Electronics, East China Normal University, Shanghai 200241, China
6. Jihua Laboratory, Foshan, Guangdong 528200, China