Institution: | 1. Institute for Materials Research , Tohoku University , 2-1-1 Katahira, Aoba-ku , Sendai , 980-8577 , Japan ysatoh@imr.tohoku.ac.jp;3. Institute for Materials Research , Tohoku University , 2-1-1 Katahira, Aoba-ku , Sendai , 980-8577 , Japan |