[1] Fac. of Chem. Eng. and Materials, Dalian Institute of Light Industry, Dalian 116034, China
[2] Department of Electronic Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
[3] Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130021, China