Department of Mathematics and Physics Shijiazhuang Tiedao University Shijiazhuang 050043 China;
Institute of Applied Physics Shijiazhuang Tiedao University Shijiazhuang 050043 China;
Department of Physics Royal Institute of Technology(KTH) SE-10691 Stockholm Sweden;
China Institute of Atomic Energy P.O.Box 275(10) Beijing 102413 China;
School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China;