PhD Physics/Engineering (Metamaterials) - Metasurfaces for mm-wave communications

Summary

The University of Exeter’s Centre for Metamaterials Research and Innovation (CMRI) with UK Government partner Dstl, is inviting applications for a fully funded PhD studentship. The stipend will be paid at the UKRI rate (£21,805 per annum on a full-time basis from October 2026). There is an enhanced budget for project costs (including travel) of £20,000. The student will be based in the Department of Physics and Astronomy at the Streatham campus in Exeter. The UK Government has undertaken a assessment of the potential of metamaterials science and technology, which is available here.

Due to the nature of the applications of the research topic, there is potential that the PhD researcher may engage in collaborations that are sensitive. Therefore, applications are restricted to those that are able to gain security clearance and limited to UK Nationals only.

Research Proposal

This PhD involves a mix of physics theory, computational modelling, and experiment, working in the department of physics at the University of Exeter. You will join a close knit team of researchers to design, build, and test a new set of ultra-thin, specially structured metasurfaces, exploring both the fundamental physics of electromagnetic materials and future applications in 6G communications. The project duration is 4 years and funded by DSTL (Defence Science and Technology Laboratory).

The research question is how to effectively shape electromagnetic waves when the wavelength reaches the millimetre (mm) scale. At lower frequencies it is common to use printed circuit antennas, which can be electronically switched between different radiation patterns and polarizations. But there are many new challenges that emerge when working with mm waves. Firstly, propagation losses tend to be larger, which means it is essential to use narrow beams. However, forming the beam is difficult because the size of the electronic elements becomes too small to easily address. Our approach is to use so-called Huygen’s metasurfaces to shape the electromagnetic wave into a beam. These are passive, intricately structured (on the scale of hundreds of microns) ultra-thin surfaces that re-shape an incident electromagnetic wave without reflection.

Our previous work has only just reached the point where all the above elements have been successfully combined [1-2]: a working multi-scale design process combining theory and numerical simulations; reflectionless (Huygens’) metasurfaces; PCB manufacture; and mm-wave experimental testing. In this project you will take this capability further. You will design a suite of mm-wave Huygens’ metasurfaces that are closely aligned with the DSTL specified application, characterize the existing untested samples, and manufacture the most promising designs.

The aims of the project are to:

1. Control metasurface bandwidth: In some applications we may want to transmit over a very narrow band of frequencies, while in others we may want broadband functionality. At the moment we do not control this in our metasurface designs, you will develop new modelling and design capabilities to be able to specify the bandwidth of our metasurface designs.
2. Control polarization: For applications we require our designs to transmit and receive different polarizations, with a controllable relative phase shift and beam direction. You will develop a set of Huygen’s metasurface designs for linear and circular polarization.
3. Towards switchability: The ultimate application of these designs is to shape mm waves in a switchable way. For this we require Huygens’ metasurfaces that can be electrically/optically modified, or have a different functionality based on the shape of the incident wave. You will extend our design capability to give e.g. pairs of designs that can be switched via a set of embedded electronic elements, or incident optical field.

References:

[1] Capers, J. R., Boyes, S. J., Hibbins, A. P., & Horsley, S. A. R. Designing the collective non-local responses of metasurfaces. Communications Physics, 4, 209 (2021).

[2] Capers, J. R., Boyes, S. J., Hibbins, A. P., & Horsley, S. A. R. Designing disordered multi-functional metamaterials using the discrete dipole approximation. New Journal of Physics, 24, 113035 (2022).

[3] Capers, J. R. and Stanfield, L. D., Sambles, J. R., Boyes, S. J., Powell, A. W., Hibbins, A. P., and Horsley, S. A. R. “Multiscale design of large and irregular metamaterials” Phys. Rev. Appl. 21, 014005 (2024).

[4] Chen, M., Kim, M., Wong, A. M. H. and Eleftheriades, G. V. Huygens’ metasurfaces from microwaves to optics: a review. Nanophotonics, 7, 1207 (2018).

About the Centre for Metamaterial Research and Innovation

You would be joining the doctoral training programme at the Centre for Metamaterial Research and Innovation (CMRI) at the University of Exeter. We provide scientific knowledge as well as transferable and technical skills training to all our students to prepare them for careers within and outside of academia.

CMRI is a community of academic, industrial, and governmental partners that harnesses world-leading research excellence from theory to application, and enables simulation, measurement, and fabrication of metamaterials and metamaterial-based devices. Our breadth of research is our centre's strength: our PhD students, researchers and academics solve multi-faceted research questions and challenges.

We are home the UK's biggest ever single investment (£19.6million) in metamaterials - MetaHUB - which was announced by the Science Minister, Lord Vallance on a visit to Exeter earlier this year. Exeter also leads the UKRI/EPSRC funded UK Metamaterials Network, which has over 1000 members from industry, academia and government, and one of the three partners in the Meta-4D EPSRC programme grant on time-varying metamaterials.

Our work spans physics, engineering, maths, and computer science, including electromagnetism (from visible and infra-red through to THz and microwave), acoustics and fluidics, undertaken in parallel with research on numerical, analytical and AI modelling techniques. The materials we work with have wide application, e.g., imaging; sensing and spectroscopy; communication and antennas; acoustic and RF signature reduction; mechanical and vibration control; energy storage and harvesting etc.

For further information regarding this studentship and to apply for it, please visit the following website: https://www.exeter.ac.uk/study/funding/award/?id=5568

Funding Notes

The stipend will be paid at the UKRI rate (£21,805 per annum on a full-time basis from October 2026). There is an enhanced budget for project costs (including travel) of £20,000.