1. Department of Physics Faculty of Science and Technology Tokyo University of Science 2641 Yamazaki Noda Chiba 278‐8510 Japan
2. The Institute for Solid State Physics The University of Tokyo 5‐1‐5 Kashiwanoha Kashiwa Chiba 277‐8581 Japan
3. Trans‐scale Quantum Science Institute The University of Tokyo Bunkyo‐ku Tokyo 113‐0033 Japan
4. Institute of Materials Structure Science High Energy Accelerator Research Organization (KEK) 1‐1 Oho Tsukuba Ibaraki 305‐0801 Japan
5. SOKENDAI (The Graduate University for Advanced Studies) 1‐1 Oho Tsukuba Ibaraki 305‐0801 Japan