1. Luminous! Centre of Excellence for Semiconductor Lighting and Displays; School of Electrical and Electronic Engineering; Nanyang Technological University; 50 Nanyang Avenue 639798 Singapore
2. School of Engineering; Brown University; Providence RI 02912 USA
3. Department of Chemistry; University of Nebraska-Lincoln; NE 68588 USA
4. Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences; Qingdao 266101 P. R. China
5. Department of Electrical and Electronic Engineering; College of Engineering; South University of Science and Technology of China; Shenzhen 518055 P. R. China