作者机构:[1]Department of Physics, Chongqing University, Chongqing 400030, China, [2]Department of Communication, Chongqing University, Chongqing 400030, China
相关基金:Project supported by the National Basic Research Program of China (Grant No 2003CB716300), the National Natural Science Foundation of China (Grant No 10575140), and CAEP Foundation (Grant Nos 2008 T0401 and 2008 T0402).