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

A D Groza

doi:10.7716/aem.v8i1.742

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.

Highlights

Surface plasmon polaritons (SPPs) are electromagnetic waves coupled to free electron oscillations traveling, typically, along a metal–dielectric interface [1]
Based on the exact solution of Maxwell's equations we investigate the nonlinear surface polaritons (NLSP) energy and propagation properties for the abovelight-line condition 0 < n < 1, namely the dependences of the NLSP propagating constant vs. the NLSP total energy flux and the dependences of the NLSP propagating constant vs. the permittivity at the surface of the nonlinear medium for different values of sheet conductance for both saturable and Kerr-like nonlinearity
In this work we investigate the threshold NLSP propagating along the guided structure consisting of a magnetic optically linear ENZ medium and a non-magnetic optically nonlinear ENZ medium with saturable permittivity separated by a flat conductive layer of zero thickness

Summary

Introduction

Surface plasmon polaritons (SPPs) are electromagnetic waves coupled to free electron oscillations traveling, typically, along a metal–dielectric interface [1]. Contrary to the properties of bulk and guided electromagnetic waves in near-zero-index structures [35,36,37,50,51], for the surface polaritons in non-magnetic media, there exists a longwavelength cutoff [52] that is an obstacle in achieving the important for quantum information processing n 0 condition. This difficulty can be overcome in magnetic media by a proper selection of the media dielectric permittivity and magnetic permeability values [53]. Based on the exact solution of Maxwell's equations we investigate the NLSP energy and propagation properties for the abovelight-line condition 0 < n < 1, namely the dependences of the NLSP propagating constant vs. the NLSP total energy flux and the dependences of the NLSP propagating constant vs. the permittivity at the surface of the nonlinear medium for different values of sheet conductance for both saturable and Kerr-like nonlinearity

Statement of the problem

Theory

Specific examples

Conclusion