[Fang, Wei; Lin, Baoqing] Huaqiao Univ, Coll Informat Sci & Engn, Inst Syst Sci, Xiamen 361021, Peoples R China.
[Fang, Wei; Lin, Baoqing] Huaqiao Univ, Coll Informat Sci & Engn, Dept Phys, Xiamen 361021, Peoples R China.
[Fang, Wei; Yang, Yaping] Tongji Univ, MOE Key Lab Adv Microstruct Mat, Sch Phys Sci & Engn, Shanghai 200092, Peoples R China.
[Li, Gao-xiang] Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.