1. Center for Optoelectronics Materials and Devices & Key Laboratory of Optical Field Manipulation of Zhejiang Province, Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China.
2. Laboratory of Information Functional Materials and Devices & State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
3. College of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China