1. Department of Chemistry City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong P. R. China
2. Department of Material Science and Engineering City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong P. R. China
3. State Key Laboratory of Millimeter Waves City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong P. R. China
4. Center for Functional Photonics City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong P. R. China