[1] Xi An Jiao Tong Univ, HCI Joint Ctr, Xian 710049, Peoples R China
[2] Natl Lab Heavy Ion Res Facil Lanzhou, Xian 710049, Peoples R China
[3] Xi An Jiao Tong Univ, Dept Appl Phys, Xian 710049, Peoples R China
[4] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China
[5] Xianyang Normal Univ, Sch Phys & Elect Engn, Xianyang 712000, Peoples R China