Institute of Theoretical Physics;
Northeast Normal University;
Changchun 130024;
Changchun Institute of Physics;
Chinese Academy of Sciences;
Changchun 130021;
Changchun Institute of Physics;
Chinese Academy of Sciences Changchun 130021;
Dipartimento di Fisica;
Politecnico di Torino;
Croso Duca degli Abruzzi 24;
10129 Torino;
Italia;