Project title: Transformation optics applied to plasmons in graphene
Supervisor: Professor Sir John Pendry, Dr Paloma Arroyo Huidobro & Professor Norbert Klein
My research is concerned with the use of transformation optics to design and characterise graphene metasurfaces, which exhibit novel wave phenomena. One of these is the study of singular gratings, which enable suprisingly broadband plasmonic effects. Another central goal of my project is to extend the concept of plasmonic metasurfaces to the temporal dimension. The plasmon dispersion relation of these gratings exhibits a peculiar near-zero gap, similar to a Dirac cone, at the center of the Brillouin zone. Since graphene plasmons lie in the THz region of the EM spectrum, by driving such a system at lower (hundreds of GHz) frequencies it is possible to induce interband transitions between different photonic states, thus enabling spectacular electromagnetic effects, such as time reversal of plasmons. Other interesting wave effects, such as one-way propagation and other non-reciprocal electromagnetic phenomena, may be realised with time-dependent metasurfaces, which lie at the forefront of current metamaterials research.