[1] Acad Sinica, Inst Theoret Phys, Beijing 100080, Peoples R China
[2] Univ Sci & Technol China, Interdisciplinary Ctr Theoret Study, Hefei 230026, Anhui, Peoples R China
[3] Chongqing Univ Posts & Telecommun, Ctr Relat & Astrophys, Chongqing 400065, Peoples R China
[4] Chongqing Univ Posts & Telecommun, Coll Elect Engn, Chongqing 400065, Peoples R China