Enhanced epsilon-near-zero structures for photonics

Abstract

We present an experimental realization of a novel layered metamaterial we label enhanced epsilon-near-zero (eENZ). The structure is a stack of alternating thin films made of ENZ– and dielectric material and it can be designed for desired refractive/reflective properties by appropriately tuning the film thicknesses. The structure supports thin film resonances, guided modes and Ferrel-Berreman plasmon modes and the performance of the structure shows a large improvement to many currently available bulk ENZ materials. Additionally, we recently demonstrated the possible use of eENZ for coherence switching in lasers [1]. We demonstrate the design, fabrication and characterization of the optical properties of the eENZ stack and compare the measured transmission properties with transfer matrix method (TMM) simulations.