1. Department of Physics, East China Normal University, Shanghai 200241, China
2. State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
3. CAS Key Laboratory of Energy conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
4. Materials Genome Institute, Shanghai University, Shanghai 200444, China
5. Materials Science and Engineering Department, University of Washington, Seattle, Washington 98195, USA