Theory of Spatial Optical Solitons in Metallic Nanowire Materials

TL;DR

This paper investigates how arrays of metallic nanowires embedded in Kerr-type materials support unique spatial optical solitons, revealing conditions for their formation and the potential for subwavelength light confinement.

Contribution

It introduces an effective medium model for nanowire arrays and uncovers the conditions under which spatial solitons can form in such structures, highlighting the role of host material properties.

Findings

Spatial solitons are supported only in self-defocusing host materials within the effective medium model.

The soliton beamwidth is linked to the hyperbolicity of the photonic isofrequency surfaces.

Strong electric fields can enable subwavelength solitary waves.

Abstract

We characterize the spatial optical solitons supported by arrays of metallic nanowires embedded in Kerr-type material. The array of nanowires is described using an effective medium model and is regarded as a continuous medium. It is shown that the conditions necessary for the formation of spatial-solitons are radically different in presence of the nanowires, and in particular within the effective medium model spatial-solitons are allowed in the nanowire material only in case the host material is a "self-defocusing" material. It is proven that the characteristic soliton beamwidth is related to the degree of hyperbolicity of the isofrequency surfaces of the photonic states, and that a sufficiently strong electric field amplitude may enable subwavelength solitary waves.