Tunable Plasmonic and Hyperbolic Metamaterials Based on Enhanced Nonlinear Response

Christos Argyropoulos,Francesco Monticone,Nasim Mohammadi Estakhri,Andrea Alù

doi:10.1155/2014/532634

Christos Argyropoulos, Francesco Monticone + Show 2 more

Open Access

https://doi.org/10.1155/2014/532634

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Abstract

We present here tunable and reconfigurable designs of linear and nonlinear plasmonic and hyperbolic metamaterials. Rich scattering features of multilayered composite nanoparticles are demonstrated, which include complex and exotic scattering signatures combining multiple dipolar Fano resonances and electromagnetic induced transparency (EIT) features. These dipole-dipole multi-Fano scattering responses can be further tuned through altering the plasmonic properties of the concentric layers or the permittivity of the core, for instance, by the presence of nonlinearities. Strong third-order nonlinear effects, such as optical bistability, may also be induced in the scattering response of nonlinear nanoparticles due to the highly enhanced and confined fields inside their core. Nonlinear hyperbolic metamaterial designs are also explored, which can realize tunable positive-to-negative refraction at the same frequency, as a function of the input intensity. Negative Goos-Hänchen shift is demonstrated based only on the hyperbolic dispersion properties of these layered metamaterials without the usual need of negative index metamaterials. The Goos-Hänchen shift may be tuned from positive-to-negative values, when the structure is illuminated with different frequencies. A plethora of applications are envisioned based on the proposed tunable metamaterials, such as ultrafast reconfigurable imaging devices, tunable sensors, novel nanotag designs, and efficient all-optical switches and memories.

Highlights

Metamaterials are artificially constructed materials that can exhibit novel functionalities not available in nature
We have presented here tunable and reconfigurable plasmonic metamaterial designs using linear and nonlinear materials
Multilayered plasmonic composite nanoparticles have been demonstrated to achieve exotic and complex scattering responses, which may be tuned at will, as we change the doping level of the semiconductor layers or the permittivity of the dielectric core

Summary

Introduction

Metamaterials are artificially constructed materials that can exhibit novel functionalities not available in nature Unusual electromagnetic properties, such as negative refraction [1] and invisibility [2, 3], have been achieved with different metamaterial structures. We further study the interesting scattering properties of multilayered plasmonic nanoparticles in order to demonstrate tunable Fano-comb operation for sensing and nanotagging applications. Third-order optical nonlinear materials loaded in the core of these plasmonic composite nanoparticles are shown to induce large bistability for each dipolar Fano resonance, due to the enhanced and strongly localized electric fields inside the core of the device. Reconfigurable nonlinear hyperbolic layered metamaterial structures will be studied, which may achieve tunable positive-to-negative refraction as a function of the input radiation intensity [38]. Reconfigurable operation for Goos-Hanchen shift will be presented based on layered metamaterial structures as a function of the frequency of the impinging radiation

Plasmonic Composite Nanoparticles

Hyperbolic Metamaterials

Conclusions