[1] Hong Kong Baptist Univ, CALM, Kowloon, Hong Kong, Peoples R China
[2] Hong Kong Baptist Univ, Dept Phys, Kowloon, Hong Kong, Peoples R China
[3] Sun Yat Sen Univ, Sch Chem & Chem Engn, State Key Lab Optoelect mat & Technol, Guangzhou 510275, Peoples R China
[4] Natl Chiao Tung Univ, Display Inst, Microelect & Informat Sys Res Ctr, Hsinchu 300, Taiwan
[5] Nanjing Univ Posts & Telecommun, IAM, Nanjing 210003, Jiangsu, Peoples R China