1. State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China
2. Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Science Beijing 100049 China
3. Technical Center for Multifunctional Magneto‐Optical Spectroscopy (Shanghai) Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education) Department of Materials School of Physics and Electronic Science East China Normal University Shanghai 200241 China
4. State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China
5. Department of Materials Science Fudan University Shanghai 200433 China
6. Department of Physics Department of Materials Science and Engineering, and Department of Biomedical Engineering City University of Hong Kong Tat Chee Avenue, Kowloon Hong Kong China