1. Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, People's Republic of China
2. State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China
3. Research Institute of Superconductor Electronics (RISE), School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, People's Republic of China
4. Key Laboratory of Spintronics Materials, Devices and Systems of Zhejiang Province, Hangzhou 311300, People's Republic of China
5. Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
6. York-Nanjing Joint Centre for Spintronics and NanoEngineering, Departments of Electronics, University of York, York YO10 5DD, United Kingdom