Not everything was negative
Speaker: Sir John B. Pendry, Imperial College London
Abstract: Changing the sign of the refractive index has caused much controversy in the optics community. Veselago was the first to point out some of the remarkable counter-intuitive properties of negative refraction but it took the advent of metamaterials to realise the concept and to generate the fiercest arguments. I shall review some of the early history highlighting why ideas such as the perfect lens were controversial and how the controversy was resolved and concluding with the challenges remaining.
Brief Biosketch: John Pendry has made seminal contributions to surface science, disordered systems and photonics. His most recent work has introduced a new class of materials, metamaterials, whose electromagnetic properties depend on their internal structure rather than their chemical constitution. Pendry discovered that a Œperfect lens¹ manufactured from negatively refracting material would circumvent Abbé¹s diffraction limit to spatial resolution, which has stood for more than a century. His most recent innovation of Œtransformation optics¹ gives the metamaterial specifications required to rearrange electromagnetic field configurations at will, by representing the field distortions as a warping of the space in which they exist. In its simplest form the theory shows how we can direct field lines around a given obstacle and thus provide a Œcloak of invisibility¹, which was first realised at Duke in 2006.