1. Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
2. School of Physical Sciences, CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing 100049, China
3. School of Sciences, Henan University of Technology, Zhengzhou, Henan 450001, China
4. Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China