1. School of Materials Science and Engineering Peking University Beijing 100871 P. R. China
2. Key Laboratory of Textile Science and Technology Ministry of Education College of Textiles Donghua University Shanghai 201620 P. R. China
3. Innovation Center for Textile Science and Technology Donghua University Shanghai 201620 P. R. China
4. International Center for Quantum Materials and Electron Microscopy Laboratory School of Physics Peking University Beijing 100871 P. R. China
5. BIC‐ESAT College of Engineering Peking University Beijing 100871 P. R. China