Non-local Ponderomotive Nonlinearity in Plasmonic

TL;DR

This paper investigates a unique nonlinearity in surface plasmon polaritons caused by electron density depletion in high-field regions, deriving nonlinear coefficients and predicting phenomena like cutoff and zero group velocity.

Contribution

It introduces a new nonlocal ponderomotive nonlinearity model for surface plasmon polaritons at metal interfaces, with derived coefficients matching experimental data.

Findings

Nonlinear coefficients comparable to experimental values

Prediction of nonlinear induced cutoff

Prediction of vanishing group velocity

Abstract

We analyze an inherent nonlinearity of Surface Plasmon Polaritons at the interface of Fermi-Dirac metal plasma, stemming from the depletion of electron density in high-field intensity regions. The derived optical nonlinear coefficients are comparable to the experimental values for metals. We calculate the dispersion relations for the nonlinear propagation of high-intensity Surface Plasmon Polaritons, predicting a nonlinear induced cutoff and vanishing group velocity.