[1] Tohoku Univ, Lab Nanoelect & Spintron, Elect Commun Res Inst, Aoba Ku, 2-1-1 Katahira, Sendai, Miyagi 9808577, Japan
[2] Tohoku Univ, Ctr Spintron Integrated Syst, Aoba Ku, 2-1-1 Katahira, Sendai, Miyagi 9808577, Japan
[3] Tohoku Univ, Ctr Spintron Res Network, Aoba Ku, 2-1-1 Katahira, Sendai, Miyagi 9808577, Japan
[4] Tohoku Univ, WPI Adv Inst Mat Res, Aoba Ku, 2-1-1 Katahira, Sendai, Miyagi 9808577, Japan
[5] Tohoku Univ, Ctr Innovat Integrated Elect Syst, Aoba Ku, 468-1 Aramaki Aza Aoba, Sendai, Miyagi 9800845, Japan