1. School of Physical Science and Technology
2. Inner Mongolia Key Lab of Nanoscience and Nanotechnology
3. Inner Mongolia University
4. Hohhot
5. P. R. China
6. College of Science
7. Nanjing Forestry University
8. Nanjing 210037
9. China
10. State Key Laboratory of Luminescence and Applications
11. Changchun Institute of Optics
12. Fine Mechanics and Physics
13. Chinese Academy of Sciences
14. Changchun 130033