Interferometric description of optical metamaterials

TL;DR

This paper presents a simple interferometric model for optical metamaterials, enabling fast and accurate calculations of their electromagnetic properties, including anisotropic and spatially dispersive effects.

Contribution

It introduces a theoretical framework modeling metamaterials as arrays of nanoparticle sheets using interfering plane waves, simplifying analysis and computation.

Findings

Model accurately predicts optical responses of metamaterials

Enables efficient retrieval of effective refractive index and impedance

Applicable to anisotropic and spatially dispersive metamaterials

Abstract

We introduce a simple theoretical model that describes the interaction of light with optical metamaterials in terms of interfering optical plane waves. In this model, a metamaterial is considered to consist of planar arrays of densely packed nanoparticles. In the analysis, each such array reduces to an infinitely thin homogeneous sheet. The transmission and reflection coefficients of this sheet are found to be equal to those of an isolated nanoparticle array and, therefore, they are easy to evaluate numerically for arbitrary shapes and arrangements of the particles. The presented theory enables fast calculation of electromagnetic fields interacting with a metamaterial slab of an arbitrary size, which, for example, can be used to retrieve the effective refractive index and wave impedance in the material. It is also shown to accurately describe optically anisotropic metamaterials that in addition exhibit strong spatial dispersion, such as bifacial metamaterials.