作者机构:[1]Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China, [2]State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
相关基金:Supported by the National Basic Research Program of China (973 Program No. 2007CB936000), the National Natural Science Foundation of China (No. 10874198, 90923002, 21073222 and 10975175, No. 10874030), and the Chinese Academy of Sciences (No. KJCX2-EW-N03)