1. Professor Emeritus, Kobe University, Kobe 657-8501, Japan
2. Department of Physics, Tokyo Institute of Technology, Meguro, Tokyo 152-8551, Japan
3. Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297, Japan
4. Japan Atomic Energy Agency, SPring-8, Sayo, Hyogo 679-5148, Japan
5. Transformative Research-Project on Iron Pnictide, JST, Kawaguchi, Saitama 332-0012, Japan
6. Department of Physics, Kyushu University, Fukuoka 812-8581, Japan