1. Research School of Physics The Australian National University Canberra ACT 2601 Australia
2. Department of Physics Jahangirnagar University Savar Dhaka 1342 Bangladesh
3. Department of Physics University of Puerto Rico Mayaguez PR 00681 USA
4. Information Device Science Laboratory Nara Institute of Science and Technology (NAIST) Nara 630‐0192 Japan
5. School of Photovoltaic and Renewable Energy Engineering University of New South Wales (UNSW Sydney) Kensington NSW 2052 Australia
6. School of Materials Science and Engineering University of New South Wales Sydney 2052 Australia