1. Graduate School of Engineering, Tohoku University, Aza-Aoba 6-6-11, Aramaki, Aoba-ku, Sendai 980-8579, Japan
2. New Industry Creation Hatchery Center, Tohoku University, Aza-Aoba 6-6-10, Aramaki, Aoba-ku, Sendai 980-8579, Japan
3. Nippon Yttrium Co., Ltd, Tosen, Omuta, Fukuoka 836-0003, Japan
4. Graduate School of Engineering, Tohoku University, Aza-Aoba 6-6-11, Aramaki, Aoba-ku, Sendai 980-8579, Japan and New Industry Creation Hatchery Center, Tohoku University, Aza-Aoba 6-6-10, Aramaki, Aoba-ku, Sendai 980-8579, Japan