1. Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 P. R. China
2. School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 P. R. China
3. Department of Physics and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligent Systems Huaiyin Normal University Huai'an 223300 P. R. China