[1] Univ New South Wales, Sch Mat Sci & Engn, Sydney, NSW 2052, Australia
[2] Nanyang Technol Univ, Ctr OptoElect & Biophoton, Sch Elect & Elect Engn, Singapore 639798, Singapore
[3] Nanyang Technol Univ, Photon Inst, Singapore 639798, Singapore
[4] King Abdullah Univ Sci & Technol, Comp Elect & Math Sci & Engn Div, Thuwal 239556900, Saudi Arabia
[5] Univ New South Wales, Fac Engn, Grad Sch Biomed Engn, Sydney, NSW 2052, Australia
[6] Huazhong Univ Sci & Technol, Sch Opt & Elect Informat, Wuhan 430074, Peoples R China
[7] City Univ Hong Kong, Dept Mat Sci & Engn, Kowloon, Hong Kong 999077, Peoples R China
[8] Univ Alabama, Dept Met & Mat Engn, Tuscaloosa, AL 35487 USA