1. Key Laboratory of Novel Materials for Sensor of Zhejiang Province, College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, P. R. China
2. State Key Lab of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, P. R. China
3. South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, P. R. China