1Institute of Electromagnetics and Acoustics and Key Laboratory of Electromagnetic Wave Science and Detection Technology, Xiamen University, Xiamen 361005, China
2State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
3Terahertz Research Center, University of Electronic Science and Technology of China, Chengdu 610054, China
4Microsystem and Terahertz Research Center, China Academy of Engineering Physics, Mianyang 621900, China
5School of Physical Science and Technology and Institute of Theoretical and Applied Physics, Soochow University, Suzhou 215006, China