[1] Tokyo Inst Technol, Mat & Struct Lab, Midori Ku, Yokohama, Kanagawa 268503, Japan
[2] Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA
[3] Int Superconduct Technol Ctr, Superconduct Res Lab, Koto Ku, Tokyo 1350062, Japan
[4] Tokyo Inst Technol, Frontier Res Ctr, Midori Ku, Yokohama, Kanagawa 2268503, Japan