1. Department of Physics
2. Nagoya University
3. Nagoya 464-8602
4. Japan
5. State Key Laboratory of High Performance Ceramics and Superfine Microstructure
6. Shanghai Institute of Ceramics
7. Chinese Academy of Sciences
8. Shanghai 200050
9. China
10. College of Science
11. China University of Petroleum (East China)
12. Qingdao 266580
13. School of Optoelectronic Engineering
14. Zaozhuang University
15. Zaozhuang