1. MOE Key Laboratory of New Processing Technology for Nonferrous Metals and MaterialsGuangxi Universities Key Laboratory of Non‐ferrous Metal Oxide Electronic Functional Materials and DevicesCollege of Materials Science and EngineeringGuilin University of Technology Guilin 541004 P. R. China
2. Shanghai Institute of Applied PhysicsChinese Academy of Sciences 239 Zhang Heng Road Pudong District Shanghai 201204 P. R. China
3. Key Lab of Design & Assembly of Functional NanostructureFujian Institute of Research on the Structure of MatterChinese Academy of Sciences Fuzhou Fujian 350002 China