1. Department of Applied Physics
2. KTH Royal Institute of Technology
3. Stockholm
4. Sweden
5. Department of Theoretical Chemistry and Biology
6. S-10691 Stockholm
7. Centre for Optical and Electromagnetic Research
8. South China Academy of Advanced Optoelectronics
9. South China Normal University
10. Guangzhou 510006
11. China
12. Federal Institute of Materials Research and Testing (BAM)
13. Division of Biophotonics
14. 12489 Berlin
15. Germany
16. College of Chemistry and Chemical Engineering