1. Department of Materials Chemistry, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
2. Department of Electrical and Computer Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
3. Technical Division, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan