[1] Tohoku Univ, WPI AIMR, Aoba Ku, 2-1-1 Katahira, Sendai, Miyagi 9808577, Japan
[2] Natl Inst Mat Sci, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan
[3] Southwest Jiaotong Univ, Sch Mat Sci & Engn, Minist Educ, Key Lab Adv Technol Mat, Chengdu 610031, Sichuan, Peoples R China