1. Department of Engineering, Lancaster University, Lancaster, U.K.
2. Department of Computing and Communications, Lancaster University, Lancaster, U.K.
3. TeraView Ltd., Cambridge, U.K.
4. Laboratory of Optics, Terahertz and Nondestructive Testing, School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou, China
5. Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, U.K.
6. Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool, U.K.