Ring-Like Solitons in Plasmonic Fiber Waveguide Composed of Metal-Dielectric Multilayers

TL;DR

This paper introduces a novel plasmonic fiber waveguide with metal-dielectric multilayers that supports subwavelength ring-like solitons, with confinement enhanced by increased input intensity, applicable to visible and near-infrared light.

Contribution

It develops a theoretical model for a plasmonic fiber waveguide with nonlinear modes, revealing stable subwavelength ring solitons and their intensity-dependent confinement enhancement.

Findings

Discovery of subwavelength ring-like solitons in the waveguide.

Confinement improves with increased input light intensity.

Applicable to visible and near-infrared wavelengths.

Abstract

We design a plasmonic fiber waveguide (PFW) composed of coaxial cylindrical metal-dielectric multilayers in nanoscale, and constitute the corresponding dynamical equations describing the modes of propagation in the PFW with the Kerr nonlinearity in the dielectric layers. The physics is connected to the discrete matrix nonlinear Schr\"{o}dinger equations, from which the highly confined ring-like solitons in scale of subwavelength are found both for the visible light and the near-infrared light in the self-defocusing condition. Moreover, the confinement could be further improved when increasing the intensity of the input light due to the cylindrical symmetry of the PFW, which means both the width and the radius of the ring are reduced.