Surface waves propagating along the interface separating an exponential graded-index medium and the medium with a step change in the dielectric constant

Abstract

New type of the surface wave propagating along the interface between the exponentially graded-index medium and the nonlinear medium characterized by a sharp-step dependence of the dielectric function on the eclectic field amplitude is described. The wave equation with new form of complicated dielectric function consisting of an exponential profile in the graded-index medium and the part with an abrupt change in dielectric constant in dependence on the eclectic field is formulated. The exact solution to equation formulated describing the transverse electric surface wave is found, and the properties of the wave distribution are described analytically. The waveguide modes excited in the wide exponential graded-index medium are found. It is derived that an increase in the order of the waveguide mode can be obtained by increasing the characteristic thickness of the exponential graded-index layer. It is shown the possibility to control the level of light intensity and energy in different regions of the contacting media near the interface by value selecting of the characteristic thickness of the graded-index layer or the effective refractive index.