1. Computer, Electrical, and Mathematical Sciences and Engineering (CEMSE) Division King Abdullah University of Science and Technology (KAUST) Thuwal 23955‐6900 Saudi Arabia
2. School of Materials Science and Engineering University of New South Wales (UNSW) Sydney NSW 2052 Australia
3. Institute of Physics Academia Sinica Nankang Taipei 115 Taiwan
4. Department of Materials Science and Engineering National Taiwan University of Science and Technology Taipei 106 Taiwan
5. Department of Materials Science Fudan University Shanghai 200433 P. R. China
6. Department of Materials Science and Engineering City University of Hong Kong Hong Kong SAR 999077 China