1. The Guo Photonics Laboratory, State Key Laboratory of Applied Optics Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP)Chinese Academy of Sciences (CAS) Changchun 130033 P. R. China
2. University of Chinese Academy of Sciences Beijing 100049 P. R. China
3. Beijing National Laboratory for Molecular ScienceKey Laboratory of Organic Solids Beijing 100190 P. R. China
4. The Institute of OpticsUniversity of Rochester Rochester NY 14627 USA