1. Department of Chemistry; Hong Kong University of Science and Technology; Clear Water Bay KowLoon Hong Kong China
2. Institute of Optoelectronic Materials and Devices; State Key Laboratory of Luminescent Materials and Devices; South China University of Technology Guangzhou; 510640 P. R. China
3. Department of Physics; North Carolina State University; Raleigh NC 27695 USA
4. Polyera Corporation; 8045 Lamon Avenue Skokie Illinois 60077 USA
5. Department of Physics; Hong Kong University of Science and Technology; Clear Water Bay KowLoon Hong Kong China