作者机构:[1]Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China, [2]International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China
相关基金:Project supported by the National Natural Science Foundation of China (Grant Nos. 50832002 and 10874035), and the National Basic Research Program of China (Grant No. 2009CB623303).