School of Physics and Information Technology Shaanxi Normal University Xi 'an 710062 China;
Department of Physics Kansas State University Manhattan KS 66506 USA;
School of Physics and Electronics Qiannan Normal College for Nationalities Duyun 558000 China;
College of Physics and Optoelectronics Technology Baoji University of Arts and Sciences Baoji 721016 China;
College of Mathematics and Information Science Baoji University of Arts and Sciences Baoji 721013 China;
Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China;
School of Physics and Electronic Technology Liaoning Normal University Dalian 116029 China;