1. Key Laboratory of Materials Physics of Ministry of Education School of Physics and Microelectronics Zhengzhou University Daxue Road 75 Zhengzhou 450052 China
2. State Key Laboratory of Superhard Materials Key Laboratory of Automobile Materials of MOE and College of Materials Science and Engineering Jilin University Changchun 130012 China
3. State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Qianjin Street 2699 Changchun 130012 China