1. Institute for Solid State Physics, University of Tokyo, Kashiwanoha, Chiba 277-8581, Japan
2. Department of Physics, University of Tokyo, Hongo, Tokyo 113-0033, Japan
3. Institute for Molecular Science, Okazaki, Aichi 444-8585, Japan
4. Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198, Japan
5. RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
6. Institute for Materials Research, Tohoku University, Sendai, Miyagi 980-8577, Japan
7. Center for Spintronics Research Network, Tohoku University, Sendai, Miyagi 980-8577, Japan
8. Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Miyagi 980-8577, Japan
9. Graduate School of Material Science, University of Hyogo, Koto, Hyogo 678-1297, Japan