Modulating light with light via giant nano-opto-mechanical nonlinearity of plasmonic metamaterial

TL;DR

This paper introduces a novel nano-opto-mechanical nonlinearity in plasmonic metamaterials, enabling light modulation with light at low power levels, which could advance optical signal processing technologies.

Contribution

It reports the discovery of a new nano-opto-mechanical nonlinearity in plasmonic metamaterials supported by flexible nano-membranes, allowing light modulation with minimal power.

Findings

Demonstrated light modulation using milliwatt power lasers.

Reversible structural reconfiguration induced by light.

Achieved modulation in a 100 nm thick film.

Abstract

From the demonstration of saturable absorption by Vavilow and Levshin in 1926, and with invention of the laser, unavailability of strongly nonlinear materials was a key obstacle for developing optical signal processing, in particular in transparent telecommunication networks. Today, most advanced photonic switching materials exploit gain dynamics and near-band and excitonic effects in semiconductors, nonlinearities in organic media with weakly-localized electrons and nonlinearities enhanced by hybridization with metamaterials. Here we report on a new type of artificial nonlinearity that is nano-opto-mechanical in nature. It was observed in an artificial metamaterial array of plasmonic meta-molecules supported by a flexible nano-membrane. Here nonlinearity is underpinned by the reversible reconfiguration of its structure induced by light. In a film of only 100 nanometres thickness we demonstrated modulation of light with light using milliwatt power telecom diode lasers.