1. Beijing National Laboratory for Condensed Matter Physics Key Laboratory for Nanoscale Physics and Devices Institute of Physics Chinese Academy of Sciences Beijing 100190 China
2. School of Physical Sciences University of Chinese Academy of Sciences Beijing 100190 China
3. Songshan Lake Materials Laboratory Dongguan Guangdong 523808 China
4. Beijing Key Laboratory for Nanomaterials and Nanodevices Beijing 100190 China
5. Institute of Advanced Materials Beijing Normal University Beijing 100875 China
6. National Institute for Materials Science 1‐1 Namiki Tsukuba 305‐0044 Japan