1. Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
2. Department of Mechanical Engineering, Nara National College of Technology, Yamatokoriyama, Nara 639-1080, Japan
3. Department of Electronic Engineering, Tohoku University, Sendai 980-8579, Japan
4. Department of Applied Physics, Tohoku University, Sendai 980-8579, Japan