1. Research Center for Ultra-High Voltage Electron Microscopy, Osaka University 1 , 7-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
2. Graduate School of Engineering, Osaka University 2 , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
3. Institute of Materials and Systems for Sustainability, Nagoya University 3 , Furo-cho, Chikusa, Nagoya 464-8601, Japan