Affiliation: | 1. Key Laboratory of Materials Physics, CAS Center for Excellence in Nanoscience, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, P. R. China;2. Department of Materials Science & Engineering University of Science and Technology of China, Hefei, P. R. China;3. Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV, USA;4. Institute of Technical Biology and Agriculture Engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, P. R. China |