Nonlinear optics in waveguides doped with dimers of metal nanoparticles

SANCHEZ, A. D.; LINALE, N.; FIERENS, P. I.; GROSZ, D. F.

Conferencia; Frontiers in Optics 2020; 2020

The Optical Society

We put forth a simple model that allows to obtain the nonlinear coefficient of a waveguide doped with dimers of Ag and Au, and calculate the doped-waveguide effective third-order susceptibility. Our model captures the nature of the plasmon hybridization in an equivalent single nanoparticle whose dielectric function and size are derived. We obtain a gap-dependent nonlinear coefficient higher than that of waveguides doped with single-nanoparticles. Finally, a modulation-instability (MI) analysis reveals a complex nonlinear response depending upon the dimer gap, including the emergence of ultra-narrow gain bands.