1. Department of Quantum Matter, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashihiroshima, Hiroshima 739-8530, Japan
2. Cryogenics and Instrumental Analysis Division, N-BARD, Hiroshima University, Higashihiroshima, Hiroshima 739-8526, Japan
3. Institute for Advanced Materials Research, Hiroshima University, Higashihiroshima, Hiroshima 739-8530, Japan
4. NIMS Beamline Station at SPring-8, National Institute for Materials Science, Sayo, Hyogo 679-5148, Japan
5. Department of Materials Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan