[1] Nankai Univ, Coll Elect Informat & Opt Engn, Tianjin Key Lab Optoelect Sensor & Sensing Networ, Tianjin 300350, Peoples R China
[2] Nankai Univ, Coll Elect Informat & Opt Engn, Dept Elect, Tianjin 300350, Peoples R China
[3] Zhengzhou Univ, Sch Phys & Engn, Zhengzhou 450001, Peoples R China
[4] Zhengzhou Univ, Key Lab Mat Phys, Minist Educ, Zhengzhou 450001, Peoples R China