1. Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
2. Electric Power Research Institute of Guangdong Power Grid Company Limited, Guangzhou 510080, China
3. Department of Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, United Kingdom
4. Department of Electronics, Carleton University,
1125 Colonel By Drive, Ottawa K1S 5B6, Canada