1. State Key Laboratory of ASIC and SystemSchool of Information Science and TechnologyFudan University Shanghai 200433 China
2. State Key Laboratory of ASIC and SystemSchool of MicroelectronicsFudan University Shanghai 200433 China
3. School of Electronic Science and EngineeringNanjing University Nanjing 210093 China
4. National Laboratory of Solid State MicrostructuresSchool of Physics and Collaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210093 China