1. State Key Laboratory for THz and Millimeter Waves and Department of Material Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong, S.A.R.
2. Department of Physics, City University of Hong Kong, Kowloon, Hong Kong, S.A.R.
3. Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong, S.A.R.
4. School of Engineering, Institute for Bioengineering, The University of Edinburgh, King’s Buildings, Mayfield Road, Edinburgh EH9 3JL, United Kingdom
5. James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, United Kingdom