1. Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, People’s Republic of China
2. Shenzhen Research Institute, The Hong Kong Polytechnic University, Shenzhen, People’s Republic of China
3. SYSU-CMU Joint Institute of Engineering, Sun Yat-sen University, Guangdong, People’s Republic of China
4. SYSU-CMU Shunde International Joint Research Institute, Shunde, Guangdong, People’s Republic of China