1. State key Laboratory of Optical Technologies for Microfabrication, Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China
2. Department of Physics, Anhui Normal University, Wuhu 241000, China
3. Chengdu Textile Institute, Chengdu 610063, China
4. No. 1505 Linyuan Road, Jilin University, Changchun 130012, China