1. Microsystem and Terahertz Research Center; CAEP; Chengdu Sichuan 610200 P. R. China
2. National Laboratory of Solid State Microstructures and Department of Physics; Nanjing University; Nanjing Jiangsu 210093 P. R. China
3. Beijing National Laboratory for Condensed Matter Physics; Institute of Physics; Chinese Academy of Sciences; Beijing 100190 P. R. China
4. Engineering Laboratory for Optoelectronic Technology and Advanced Manufacturing; Henan Normal University; Xinxiang Henan 453007 P. R. China
5. School of Information Engineering; Southwest University of Science and Technology; Mianyang Sichuan 621010 P. R. China
6. Institute of Fluid Physics; China Academy of Engineering Physics; Mianyang Sichuan 621900 P. R. China