1. Institute of Photovoltaics, School of Physics and Materials Science, Nanchang University, Nanchang330031, China
2. Henan Key Laboratory of Infrared Materials & Spectrum Measures and Applications, Henan Normal University, Xinxiang453007, China
3. State Key Laboratory of Integrated, Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun130012, China
4. Department of Materials Science & Engineering, City University of Hong Kong, Kowloon518057, Hong Kong, China