[1] Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA
[2] CENG, MDN, SPSMS, DRFMC, F-38054 Grenoble, France
[3] Cent Res Inst Elect Power Ind, Komae, Tokyo 2018511, Japan
[4] Univ Tokyo, Dept Adv Mat Sci, Bunkyo Ku, Tokyo 1138656, Japan
[5] Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA