A method for achieving larger enhancement in Four-Wave Mixing via plasmonic path interference effects

TL;DR

This paper demonstrates how Fano resonance-induced path interference effects can significantly enhance four-wave mixing in plasmonic systems, providing a straightforward method to achieve large nonlinear enhancements.

Contribution

The paper introduces a simple equation-based approach to harness Fano resonances for maximizing four-wave mixing enhancement in plasmonic and quantum emitter systems.

Findings

Fano resonance causes cancellation of nonresonant terms, boosting nonlinearity.

Coupling with two quantum emitters further amplifies enhancement.

Explicit method guides design of highly efficient nonlinear plasmonic devices.

Abstract

Enhancement and suppression of nonlinear processes in coupled systems of plasmonic converters and quantum emitters are well-studied theoretically, numerically and experimentally, in the past decade. Here, in difference, we explicitly demonstrate --with a single equation-- how the presence of a Fano resonance leads to cancellation of nonresonant terms in a four-wave mixing process. Cancellation in the denominator gives rise to enhancement in the nonlinearity. The explicit demonstration, we present here, guides us to the method for achieving more and more orders of magnitude enhancement factors via path interference effects. We also study the coupled system of a plasmonic converter with two quantum emitters. We show that the potential for the enhancement increases dramatically due to better cancellation of the terms in the denominator.