Affiliation: | 1. International Center for Young Scientists (ICYS), World Premier International (WPI) Center for Materials Nanoarchitectonics (MANA) National Institute for Materials Science (NIMS), , Tsukuba Ibaraki, 305–0044 Japan;2. School of Physical Science and Technology, Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, , Lanzhou, 730000 P. R. China |