Above-light-line Nonlinear Surface Polaritons near a Conductive Interface: Threshold Case

Abstract

We investigate the TM-polarized nonlinear surface polaritons (NLSP) propagating along aguided structure consisting of a magnetic optically linear medium and a non-magnetic opticallynonlinear medium with saturable permittivity separated by a flat conductive layer of zerothickness. We consider those values of hosting media bulk material parameters for which theNLSP existence (for zero sheet conductance) has threshold character with respect to the wavesintensity. Based on the exact solution of Maxwell's equations we show that the energy andpropagation properties of the NLSP near the above-light-line condition (1 > n > 0) dependconsiderably on the surface conductivity of the layer, even the threshold character of the NLSPcan be lost; for certain sheet conductance values these waves can exist in a linear limit. TheNLSP propagation constant is defined by both the surface conductivity and field intensity andcan be varied in a wide diapason, which gives an opportunity to obtain and control the importantfor quantum information processing 0 n  condition. For a chosen value of the NLSPpropagation constant the NLSP field intensity and energy flux decries when the surfaceconductivity grows; saturation of the nonlinear permittivity leads to an increase of the NLSPenergy flux compared with Kerr-like nonlinearity.