[1] Shenzhen Univ, Coll Optoelect Engn, Minist Educ & Guangdong Prov, Key Lab Optoelect Devices & Syst, Shenzhen 518060, Peoples R China
[2] Cent S Univ, Sch Met & Environm, Changsha 410083, Hunan, Peoples R China
[3] Nanyang Technol Univ, Sch Mat Sci & Engn, 50 Nanyang Ave, Singapore 639798, Singapore