1. Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2600, Australia
2. Australian Research Council Centre of Excellence for Transformative Meta-Optical Systems, Research School of Physics, The Australian National University, Canberra, ACT 2600, Australia
3. Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia
4. Photon Science Institute and Department of Physics and Astronomy, School of Natural Sciences, The University of Manchester, Manchester M13 9PL, United Kingdom
5. Australian National Fabrication Facility ACT Node, Research School of Physics, The Australian National University, Canberra, ACT 2600, Australia
6. Microstructural Analysis Unit, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
7. School of Mathematical and Physical Sciences, Faculty of Science, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
8. Australian Research Council Centre of Excellence for Transformative Meta-Optical Systems, Faculty of Science, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
9. Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
10. School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia