Scattering-free plasmonic optics with anisotropic metamaterials

摘要

We consider the propagation of surface plasmon polaritons in anisotropic metamaterial systems. It is shown that material anisotropy can be used as an efficient tool to independently control effective modal index and spatial profile of the surface mode. In particular, it is possible to utilize anisotropic media to completely eliminate the out-of-plane scattering of surface plasmons, realizing the paradigm of truly two-dimensional optics where surface modes are completely uncoupled from their volume counterparts. The developed formalism yields a mapping between the familiar laws of 3D optics and the behavior of two-dimensional surface optics. The mapping is illustrated on examples of plasmonic refractor and plasmonic Bragg reflector. The tolerance of the surface optics paradigm with respect to material imperfections is assessed with perturbation theory and with numerical solutions of Maxwell's equations. Practical realizations of dynamical plasmonic circuits and extensions of the developed framework to volume-guiding structures are discussed.