Near-zero-index platform in photonics: tutorial

Abstract

The need for miniaturization and faster communications resulted in the rise of photonics, with the big promise of light circuits with high speed and low heating. Near-zero-index materials have gained attention due to their peculiar electromagnetic properties, such as enhancement of the electric field and extraordinary transmission inside photonic waveguides. Furthermore, in such a medium, light propagates with constant phase, thus holding great promise for the field of quantum photonics, where information is preserved instead of degraded by the environment, causing decoherence. However, its realization still remains challenging, as it requires very specific geometries to fulfill some requirements related to the effective medium theory. In this tutorial, we present a theoretical overview of low-index materials’ most intriguing yet useful characteristics and their prospective applications.