1. Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Siyuan Laboratory, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University, Guangzhou 510632, P. R. China
2. Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
3. Department of Physics, Chemistry, and Biology (IFM), Linköping University, Linköping SE-58183, Sweden
4. Huazhong Institute of Electro-Optics-Wuhan National Laboratory for Optoelectronics, Wuhan 430223, P. R. China
5. State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310027, P. R. China