1. Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University 1 , 1-1 Rokkodai-cho, Nada-ku, Kobe 651-8501, Japan
2. Center for Spintronics Research Network (CSRN), University of Tokyo 2 , 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
3. Institute for Chemical Research, Kyoto University 3 , Gokasho, Uji, Kyoto 611-0011, Japan
4. Center for Science and Innovation in Spintronics (CSIS), Tohoku University 4 , 2-1-1, Katahira, Aoba-ku, Miyagi 980-8577, Japan and , 1-3, Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
5. Center for Spintronics Research Network (CSRN), Osaka University 4 , 2-1-1, Katahira, Aoba-ku, Miyagi 980-8577, Japan and , 1-3, Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
6. Center for Innovative Integrated Electronics Systems (CIES), Tohoku University 5 , 468-1 Aramaki Aza Aoba, Aoba, Sendai, Miyagi 980-8572, Japan
7. Center for Spintronics Integrated Systems (CSIS), Tohoku University 6 , 2-2-1 Katahira Aoba, Sendai, Miyagi 980-8577 Japan
8. Center for Spintronics Research Network (CSRN), Tohoku University 7 , 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 Japan and , 6-6-05, Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan
9. Graduate School of Engineering, Tohoku University 7 , 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 Japan and , 6-6-05, Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan