RF and Microwave Metamaterials
RF and Microwave
RF and Microwave
Prof Bill Barnes
Light-Matter Coupling - Linking molecules with light
Traditionally, making molecules with new properties, e.g. dyes of different colours, has been the province of chemistry; new properties are based on making new molecules. Our approach is fundamentally different- we use light to alter the way molecules interact with each other, something that can lead to radical changes in their properties, without changing their chemical composition. In the RF we are making use of metamaterials as analogies of molecular systems to explore these new ideas.
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THz materials, imaging and spectroscopy; Nonlinear optics
We explore the potential for developing new THz components and sensors to fill the so called “THz gap”, utilizing novel magnetic and plasmonic responses of many materials in this region, and are currently working on novel methods for imaging in this difficult spectral region. We also work in plasmoncs, and explore the possibility of replacing coinage metals with new materials such as graphene and ITO. These materials have tuneable electromagnetic responses, as free electrons can controllably introduced by chemical, electrical or photo-doping, making the manipulating light on extreme sub-wavelength length scales possible, and we focus on enhancing nonlinear optical responses for optical switching etc.
Prof Alastair Hibbins
RF and microwave metamaterials
Our metamaterial research is built around structures that offer novel and useful material and surface performance on millimetre and centimetre scale lengths (microwave and RF). We typically design, model and experimentally charactertise structured surfaces (“metasurfaces”) , artificial atoms (“meta-atoms”), three dimensional metamaterials, and composite materials.
Our work on 2D metasurfaces is associated with the control of surface wave propagation through local control of the surface impedance boundary condition, and we are interested in 3D metamaterials to create novel electromagnetic properties that can be chosen at the point of design using the shape, size or spacing of resonant inclusions within a passive host. Compact and directional antennas, signature control, imaging and sensing, beam steering, frequency selective wallpaper, electronic tagging, and energy harvesting are just a few of the application areas that benefit from our research.
Prof Geoff Nash
Optical and Acoustic Materials and Devices
Within the NEST group we explore the fascinating characteristics of new materials including 2D materials- for example, graphene and metasurfaces. We both investigate fundamental phenomena, such as the interaction of light with molecules, and aim to exploit these phenomena to create novel technology.
Prof Feodor Ogrin
Bio-inspired magnetic systems
Many micro-organisms in the natural world have developed properties which could be invaluable for our technologies. Even a ‘simple’ motion or moving liquid at microscale can help us to revolutionise a range of practices used in medicine and biotechnology. In this research we use magnetic materials to help us creating microscopic machines that would be able to mimic micro-organisms. As well as building and controlling them the main challenge of the research is to find the ways to recreate the mechanics of the biological systems in the highly viscous environment which they are exposed to. Our research is highly interdisciplinary and, as well as the magnetic phenomena, includes such disciplines as hydrodynamics, microfluidics, mechanics and electromagnetism.
Prof Sir Roy Sambles
Electromagnetic and acoustic materials
Waves change their speed when going from one material to another - refraction. By structuring materials on the scale of the wavelength of the wave, creating so-called metamaterials, it is possible to create, by design, remarkable effects such as negative refraction or phase speeds approaching infinity. Using microwaves (wavelength of order mms) or sound (wavelength of order cms) it is relatively straightforward to make novel materials with properties not otherwise obtainable. This leads on to potential applications such as perfect radar absorbers or holey screens which allow air through but little sound. Since microwave communications and sound play such vital roles (mobile phones, TVs, radio etc.) in our everyday lives the fundamental research being undertaken here on novel metamaterials may have very significant sociological impact.
Prof Mustafa Aziz
Magnetic materials and transducers
The magnetic response of magnetic materials due to the interaction with electromagnetic fields is influenced by the magnetic properties, shape and size of the magnetic structure. Controlling the shape and size of the magnetic structure or constituents offers enhanced magnetic response, tuning capability and improved material aspects (mechanical, electrical, thermal and optical) for manufacturing and industrial applications.
My research focuses on the development of theoretical and computational electromagnetic algorithms to understand this complex interaction with discrete and continuous magnetic (meta)materials, and enable the design and engineering of high-frequency, compact composites and devices for data storage, communications and microwave applications. My work in applied magnetics also extends to the research and development of high-sensitivity, high-resolution non-destructive electromagnetic techniques for the detection and characterisation of defects and abnormalities in magnetic structures such as oil and gas steel pipes.
Prof Volodymyr Kruglyak
We study phenomena associated with spin waves (elementary excitations of the magnetic order) and magnons (their quanta). Spin waves carry energy and angular momentum via a collective wave motion of spins. So, the relation between magnonics and the rest of spin physics (aka spintronics) is akin that between the ac and dc electricity. Magnonics offers the perspective of technology that would use spin waves (or magnons) to carry and process both analog signals and digital data. The most attractive features of this technology are the low power, magnetic reconfigurability and scalability to nanometre dimensions.
Senior Lecturers / Senior Research Fellows
Dr Ian Hooper
RF and microwave metamaterials
The RF and mm-wave frequency bands are becoming ever more techologically important, with the ongoing push to increase data bandwith in wireless communications requiring the use of higher frequency radiation than was historically the case. As a result, novel devices to control the electromagentic environment at these frequencies are required, whether they be emitters and receivers (antennas), or absorbers, beam steerers, etc. In particular we are interested in devices that are reconfigurable and/or frequency-agile, and the role that metamaterials may have in such devices.
Dr Simon Horsley
Theory of electromagnetic and acoustic materials
Design of electromagnetic materials: Suppose you want to do something to a wave; perhaps redirect a radio wave, or absorb a sound wave. I use mathematics to look for the materials you need.
I am interested in the theory of electromagnetism and wave physics in general. Recently I have been thinking about how waves reflect from metamaterial structures, but I also work on the theory of quantum electromagnetism in dielectric media (I am interested in understanding how macroscopic bodies affect the quantum properties of the electromagnetic field, and how these in turn affect the motion of the object).
Dr Alex Powell
RF and Microwave Metamaterials/3D Metamaterials
My research is focussed on taking electromagnetic metamaterials into the third dimension, both in terms of their design, and fabrication through the use of advanced manufacturing methods. I am currently exploring a variety of complex 2D and 3D structures, both to understand the fundamental physics governing their behaviour, and to apply this understanding to tackle real world problems such as improving antenna directivity, designing tuneable reflectarrays for telecommunications and increasing the radar visibility of small objects such as drones and picosatellites.
Dr Yongde Xia
Nanomaterials for energy
My research covers a broad spectrum of nanomaterials and nanocomposites, with specific interests in functionality and their applications. The core research focus is to synthesize and characterise novel functional nanoporous materials, to understand the growth mechanisms, to assess their advanced mechanical and physical properties, and to apply these interesting functional nanoporous materials for practical applications in a diverse areas, from energy storage and conversion to nanodevice construction, from solar energy creation to hydrogen energy storage and greenhouse capture and conversion, and from photocatalysis and environmental catalysis for renewable energy to lightweight wearable engineering devices.