1. Beijing National Laboratory for Condensed Matter and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
2. The Cultivation Base for State Key Laboratory, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, People's Republic of China
3. College of Physics, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, People's Republic of China