[1] Cent South Univ, Sch Phys & Elect, Hunan Key Lab Super Microstruct & Ultrafast Proc, Changsha 410083, Hunan, Peoples R China
[2] Cent South Univ, Sch Phys & Elect, Hunan Key Lab Nanophoton & Devices, Changsha 410083, Hunan, Peoples R China
[3] Hunan Normal Univ, Dept Phys, Low Simens Quantum Struct & Quantum Control, Minist Educ, Changsha 410081, Hunan, Peoples R China
[4] Univ Hong Kong, Dept Mat Sci & Engn City, Kowloon, Hong Kong 999077, Peoples R China
[5] Nanjing Univ, Collaborat Innovat Ctr Adv Microstruct, Sch Elect Sci & Engn, Nanjing 210008, Jiangsu, Peoples R China