1. Materials Science and Engineering King Abdullah University of Science and Technology Thuwal 23955‐6900 Saudi Arabia
2. Shenyang National Laboratory for Materials Science Institute of Metal Research (IMR) Chinese Academy of Sciences (CAS) Shenyang 110016 China
3. Department of Physics and Astronomy, and Nebraska Center for Materials and Nanoscience University of Nebraska Lincoln NE 68588 USA
4. Imaging and Characterization Core Lab King Abdullah University of Science and Technology (KAUST) Thuwal 23955‐6900 Saudi Arabia
5. Advanced Nanofabrication Core Lab King Abdullah University of Science and Technology (KAUST) Thuwal 23955‐6900 Saudi Arabia
6. School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 P. R. China