1. Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-Based Electronics, School of Electronics, Peking University, Beijing 100871, China
2. Jihua Laboratory, Foshan, Guangdong 528200, China
3. The State Key Laboratory of Advanced Optical Communication System and Networks, School of Electronics, Peking University, Beijing 100871, China
4. Frontiers Science Center for Nano-optoelectronics, Peking University, Beijing 100871, China
5. Peng Cheng Laboratory, Shenzhen 518055, China