A microwave metamaterial comprised of mm-sized copper-cubes

Transformation optics provides the mathematical recipe to build an invisibility cloak

Metamaterials and Transformation Optics

This theme is led by Prof Roy Sambles and Prof Alastair Hibbins, Prof Bill Barnes, Dr Tom Philbin and Dr Simon Horsley, working alongside Prof Euan Hendry, Prof Rob Hicken and Prof Pete Vukusic.

Metamaterials are composite materials with properties unavailable in nature. In recent years research in metamaterials has expanded rapidly due to major advances in negatively refracting materials and “invisibility  cloaking”  in  electromagnetism.  Closely associated with this research is the subject of transformation optics, a set of theoretical tools that leads to designs for cloaking and other exotic effects requiring metamaterials for their realisation. The concepts of metamaterials and transformation optics can also be transferred to acoustics, leading to new acoustic materials and designs for manipulating sound waves.

Our research in this theme grew from studies of microwave metamateirals, where the cm- and mm-length scales offer fabrication of complex structures with relative ease, using workshop and 3d printing techniques.  Similar advantages of scale are offered through experimentation with acoustic metamaterials, and we are actively exploring this exciting new field both in air, and underwater (SONAR).  Our metamaterials portfolio exploits synergies with our plasmonics, natural photonics and disordered systems and magnonics research, and has also expanded to the terahertz and visible domains.

Across the spectrum, we are developing electromagnetic and acoustic metamaterials with novel properties and potential applications that include stealth materials, ultra-thin absorbers, compact antennas and electronic tagging. We are exploring the theoretical tools of transformation optics to manipulate wave propagation in novel materials; examples include new designs for surface-wave devices and materials that implement exotic geometries for waves.