Transformation plasmonics

Abstract

Surface plasmons polaritons (SPPs) at metal/dielectric interfaces have raised lots of expectations in the on-going quest towards scaling down optical devices. SPP optics offers a powerful and fl exible platform for real two-dimensional integrated optics, capable of supporting both light and electrons. Yet, a full exploitation of the features of SPPs is conditioned by an accurate control of their fl ow. Most efforts have so far focused on the extrapolation of concepts borrowed from guided optics. This strategy has already led to many important breakthroughs but a fully deterministic control of SPP modes remains a challenge. Recently, the fi eld of optics was stimulated by a novel paradigm, transformation optics, which offers the capability to control light fl ow in any desired fashion. While it has already signifi cantly contributed to the design of metamaterials with unprecedented optical properties, its versatility offers new opportunities towards a fully deterministic control of SPPs and the design of a new class of plasmonic functionalities. Here, we review recent progress in the application of transformation optics to SPPs. We fi rst briefl y describe the theoretical formalism of transformation plasmonics , focusing on its specifi cities over its three-dimensional optical counterpart. Numerical simulations are then used to illustrate its capability to tame SPP fl ows at a metal interface patterned with a dielectric load. Finally, we review recent experimental implementations leading to unique SPP functionalities at optical frequencies.