1. School of Science, Harbin Institute of Technology Shenzhen, University Town, Shenzhen, Guangdong 518055, P. R. China
2. State Key Laboratory on Tunable Laser Technology, Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System, Harbin Institute of Technology, Shenzhen, University Town, Shenzhen, Guangdong 518055, P. R. China
3. School of Mathematics and Physics, Shanghai University of Electric Power, 2588 Changyang Road, Shanghai 200090, P. R. China
4. Sustech Core Research Facilities, Southern University of Science and Technology, 1088 Xueyuan Blvd., Shenzhen, Guangdong 518055, P. R. China