stephen hanham

High-Efficiency Terahertz Beam Shaping with Cascaded Metasurfaces

Metasurfaces offer exceptional control over electromagnetic wavefronts, providing new degrees of freedom for compact and highly efficient beam-shaping systems. By enabling new functionality and greater design flexibility, metasurfaces have the potential to replace traditional antenna systems across a wide range of applications. In this talk, I explore the use of cascaded metasurfaces at terahertz frequencies to achieve simultaneous control over the amplitude and phase of transmitted fields, enabling high-efficiency beam shaping and functionality that is difficult to realise using a single metasurface layer. Design strategies and representative examples are presented, together with practical considerations for fabrication and implementation. This work provides a route towards broadband, low-reflection terahertz beam-shaping metasurfaces for emerging applications in imaging, sensing, and wireless communications.

Stephen Hanham is an Associate Professor in the Department of Materials at Imperial College London. His research focuses on electromagnetic materials and devices for the terahertz frequency band. He has over 100 publications in scientific journals, international conferences and book chapters spanning the fields of electronic engineering, physics and material science. Dr Hanham received his B.E. and B.Sc. degrees from the University of Western Australia in 2004 and the Ph.D. degree from the University of Sydney, Australia in 2010. From 2008 to 2010 he was a Research Project Officer and later a Systems Engineer at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Sydney, Australia working in the areas of electromagnetics and antennas, primarily aimed towards the terahertz band. From 2010 to 2017 he worked as a Postdoctoral Research Associate and then Experienced Researcher in the Physics and Materials Departments at Imperial College London researching terahertz plasmonics, near-field imaging and bio-liquid sensing. From 2017 to 2023 he was a Senior Birmingham Fellow and Associate Professor in the Department of Electronic, Electrical and Systems Engineering at the University of Birmingham, U.K.