Dr. Z. Q. Chen
Department of Physics
Wuhan University
Wuhan 430072, China
Tel/Fax: +86-27-68753880
E-mail: chenzq@whu.edu.cn

Dr. N. Qi
Department of Physics
Wuhan University
Wuhan 430072, China
Tel/Fax: +86-27-68753880
E-mail: ningqi@whu.edu.cn