1. Department of Physics, Kyushu University, Fukuoka 819-0395, Japan
2. Center for Advanced High Magnetic Field Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
3. Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297, Japan
4. SAGA Light Source, Tosu, Saga 841-0035, Japan
5. Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan