1. Department of Physical Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
2. Center for Advanced High Magnetic Field Science (AHMF), Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
3. Department of Physics, Chuo University, Bunkyo, Tokyo 112-8551, Japan
4. Institute for Solid State Physics, the University of Tokyo, Kashiwa, Chiba 277-8581, Japan
5. Department of Chemistry, Osaka University, Toyonaka, Osaka 560-0043, Japan