1. Institute for Materials Research, Tohoku University, Sendai, Japan
2. Graduate School of Engineering, Nagoya University, Nagoya, Japan
3. Institute for Materials Research, Tohoku University, Oarai, Japan
4. Research Center for Magnetic and Spintronic Materials, National Institute for Materials Science, Tsukuba, Japan
5. Center for Advanced Intelligence Project, RIKEN, Tokyo, Japan
6. SANKEN, Osaka University, Osaka, Japan