Xuanhu Chen1, Yang Xu1, Dong Zhou1, Sen Yang1, Fangfang Ren1, Hai Lu1, Kun Tang1, Shulin Gu1, Rong Zhang1, Youdou Zheng1, Jiandong Ye1
1Jiangsu
Provincial Key Laboratory of Advanced Photonic and Electronic Materials,
and School of Electronic Science and Engineering, ‡Collaborative Innovation Center
of Advanced Microstructures, and §Collaborative Innovation Center of Solid-State
Lighting and Energy-Saving Electronics, Nanjing University, Nanjing 210093, China