1. Institute of Advanced Materials (IAM)
2. Nanjing University of Posts and Telecommunications (NUPT)
3. Nanjing 210023, P. R. China
4. State Key Laboratory of Transient Optics and Photonics
5. Xi'an Institute of Optics and Precision Mechanics
6. Chinese Academy of Science (CAS)
7. Xi'an 710119, P. R. China
8. School of Optoelectronic Engineering