作者机构:[1]Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China, [2]Center of Physical Experiment and Teaching, School of Science, University of Science and Technology of China, Hefei 230026, China, [3]Electronics Department, ElectronicEngineering Institute, Hefei 230038, China
相关基金:supported by National Natural Science Foundation (No. 60602065), and Innovation Funds of University of Science and Technology of China for Graduate Student (No. KD2006009)