[1] Zhengzhou Univ, Int Lab Quantum Funct Mat Henan, Zhengzhou 450001, Peoples R China
[2] Henan Polytechn Univ, Sch Phys & Elect Informat Engn, Jiaozuo 454000, Peoples R China
[3] Key Lab Radio Frequency & Micro Nano Elect Jiangs, Nanjing 210023, Peoples R China
[4] Nanjing Univ Sci & Technol, Coll Mat Sci & Engn, Herbert Gleiter Inst Nanosci, Inst Optoelec & Nanomat, Nanjing 210094, Peoples R China
[5] Nanjing Univ Posts & Telecommunicat, Coll Elect Sci & Engn, Nanjing 210046, Peoples R China
[6] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410004, Peoples R China