[Long, Fen; Long, F] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
[Wang, Shangyun] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.
[Jing, Jiliang; Chen, Songbai] Hunan Normal Univ, Inst Interdisciplinary Studies, Synerget Innovat Ctr Quantum Effects & Applicat,Mi, Dept Phys,Key Lab Low Dimens Quantum Struct & Quan, Changsha 410081, Hunan, Peoples R China.
[Jing, Jiliang; Chen, Songbai] Yangzhou Univ, Coll Phys Sci & Technol, Ctr Gravitat & Cosmol, Yangzhou 225009, Peoples R China.