1. Institute of Applied Physics and Materials Engineering, University of MacauAvenida da Universidade Taipa Macau 999078 P. R. China
2. Department of PhysicsJiangsu University Zhenjiang Jiangsu 212013 P. R. China
3. State Key Laboratory on Tunable laser TechnologyMinistry of Industry and Information Technology Key Lab of Micro‐Nano Optoelectronic Information SystemShenzhen Graduate SchoolHarbin Institute of Technology Shenzhen 518055 China