Complex modes of nonlinear plasmonic waveguides

We analyze guided modes of a metal-dielectric-metal waveguide in the presence of losses when the dielectric core possesses the Kerr nonlinear response. After the analysis of effects of dispersion and losses on the linear complex modes, we calculate and discuss the nonlinear modes presented through the dependence of the modal power on the propagation constant. We show that nonlinearities bring many novel features to the mode properties, including novel bifurcation points and novel types of guided modes, the existence of limiting values for the propagation constant, and the possibility of a power growth for some of the modes.