[1] Chinese Acad Sci, Inst Semicond, SKLSM, Beijing 100083, Peoples R China
[2] Univ Chinese Acad Sci, Coll Mat Sci & Optoelect Technol, Ctr Mat Sci & Optoelect Engn, Beijing 100049, Peoples R China
[3] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contro, Minist Educ, Dept Phys, Changsha 410081, Peoples R China
[4] Hunan Normal Univ, Synerget Innovat Ctr Quantum Effects & Applicat, Changsha 410081, Peoples R China
[5] Zhejiang Univ, Ctr Quantum Matter, Sch Phys, Hangzhou 310027, Peoples R China