1. Key Laboratory of Luminescence and Optical Information, Ministry of Education, School of Physical Science and Engineering, Beijing Jiaotong University 1 , Beijing 100044, China
2. Institute of Optoelectronics Technology, Beijing Jiaotong University 2 , Beijing 100044, China
3. Tangshan Research Institute of Beijing Jiaotong University 3 , Tangshan 063000, China
4. School of Electronics and Information Engineering, Shenzhen University 4 , Shenzhen 518060, China