1. National Key Laboratory of Scattering and Radiation, Beijing, China
2. School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, China
3. School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing, China
4. Key Laboratory of Solid State Laser, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, China
5. Department of Electronic Engineering, Tsinghua University, Beijing, China