Scaling of the nonlinear response of the surface plasmon polariton at a metal/dielectric interface

Plasmonic systems involve interfaces containing metal and dielectric materials. In an effort to investigate the scaling of the nonlinear response of the surface plasmon polariton at a metal/dielectric interface, where the metal and dielectric present optical nonlinearity, we introduce a figure-of-merit that quantifies the contribution of the metal and the dielectric to the nonlinear response in this specific situation. In the case of self-action of the surface plasmon polariton for the gold/dielectric interface, we predict that the dielectric nonlinear response is dominant for strongly nonlinear dielectrics such as polydiacetylenes, chalcogenide glasses, or even semiconductors. The gold nonlinear response is dominant only in cases involving weakly nonlinear dielectrics such as silicon dioxide or aluminum oxide. We verify the relevance of the metric by investigating the process of optical switching via the third-order nonlinear response and discuss which gold/dielectric combinations have better switching behaviors.