Surface-induced nonlinearity enhancement in subwavelength rod waveguides

Abstract

We develop a perturbative theory to describe optical propagation in subwavelength rod waveguides. In this approach, we account for loss and nonlinearity in the boundary conditions. A comparison to the traditional perturbative approach used in optical fibers reveals that the surface contribution provides a significant nonlinearity enhancement in the subwavelength regime. We further compare the nonlinearity enhancement of metallic, dielectric, and semiconductor waveguides, in addition to determining the attenuation coefficient of metallic nanowires. © 2011 American Physical Society.