1. Engineering
Research Center for Nanophotonics and Advanced Instrument, Ministry
of Education, and Department of Physics, East China Normal University, Shanghai 200062, China
2. School of Automation Engineering, Shanghai University of Electric Power, Shanghai 200090, China
3. Department
of Physics, Institute of Advanced Materials, and Institute of Research
and Continuing Education (Shenzhen), Hong Kong Baptist University, Kowloon
Tong, Hong Kong