1. Department of Physics
2. College of Science
3. Yanbian University
4. Yanji 133002
5. China
6. Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education
7. Jilin Normal University
8. Siping 136000
9. State Key Laboratory of Luminescence and Applications
10. Changchun Institute of Optics, Fine Mechanics and Physics
11. Chinese Academy of Sciences
12. Changchun 130033