1. Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568, Japan
2. Advanced Manufacturing Research Institute, AIST, Tsukuba, Ibaraki 305-8564, Japan
3. Department of Engineering and Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577, Japan
4. Biotechnology Research Institute for Drug Discovery, AIST, Tsukuba, 305-8565 Ibaraki, Japan
5. Department of Electronic Engineering, Tohoku University, Sendai, 980-8579 Miyagi, Japan
6. Nanotube Research Center, AIST, Tsukuba, 305-8565 Ibaraki, Japan