1. School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China Chengdu P. R. China
2. State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of China Chengdu P. R. China
3. School of MicroelectronicsXidian University Xian China
4. National Laboratory of Solid State MicrostructuresSchool of Electronic Science and Engineering, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University Nanjing China