1. Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material Physics Ministry of Education School of Physics and Microelectronics Zhengzhou University Zhengzhou 450052 China
2. Microsystem and Terahertz Research Center CAEP Chengdu 610200 China
3. Institute of Electronic Engineering CAEP Mianyang 621999 China
4. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen 518060 China