John PENDRY is a condensed matter theorist working at Imperial College London. His early work addressed electronic and structural properties of surfaces developing the theory of low energy diffraction, EXAFS, and of electronic surface states later moving on to studies of transport in disordered systems. In the mid 1990's he turned his attention to metamaterials and proposed several structures which radically influenced the development of the field leading to the experimental discovery of negative refraction by the Smith group and later, also in collaboration with David Smith, the design of a cloak of invisibility. His investigation of negative refraction led to the discovery that it is theoretically possible to design a lens whose resolution is limited only by the perfection of manufacture, not by the well known Abbé law which limits resolution to the order of the wavelength. The technique of transformation optics which he pioneered has led to many applications in the field of plasmonics, particularly building on the perfect lens concept and showing how to concentrate light into sub nanoscale volumes. His most recent work is the topic of today's talk and moves the study of metamaterials on to structures that vary in time as well as in space.
