1. State Key Laboratory for Artificial Microstructure & Mesoscopic PhysicsSchool of PhysicsPeking University Beijing 100871 P. R. China
2. Zhejiang Province Key Laboratory of Quantum Technology and DeviceDepartment of PhysicsZhejiang University Hangzhou 310027 P. R. China
3. Australian Nuclear Science and Technology Organisation (ANSTO) New Illawarra Road, Lucas Heights Sydney NSW 2234 Australia
4. Beijing Key Laboratory for Magnetoelectric Materials and Devices Beijing 100871 P. R. China
5. Department of Materials Science and EngineeringCollege of EngineeringPeking University Beijing 100871 P. R. China
6. Collaborative Innovation Center of Quantum Matter Beijing 100871 P. R. China