Observations of zero-order bandgaps in negative-index photonic crystal superlattices at the near-infrared

TL;DR

This paper reports the first experimental observation of zero-order bandgaps in near-infrared negative-index photonic crystal superlattices, demonstrating a new type of photonic band gap with potential for advanced wavefront control.

Contribution

It provides the first experimental evidence of zero-n bandgaps in negative-index photonic superlattices, confirmed by numerical simulations and applicable across various superlattice configurations.

Findings

Zero-order bandgaps observed in near-infrared photonic superlattices.

Experimental results agree with theoretical predictions.

Potential applications in wavefront control and cavity resonances.

Abstract

We present the first observations of zero-n bandgaps in photonic crystal superlattices consisting of alternating stacks of negative index photonic crystals and positive index dielectric materials in the near-infrared. Guided by ab initio three-dimensional numerical simulations, the fabricated nanostructured superlattices demonstrate the presence of zero-order gaps in remarkable agreement with theoretical predictions across a range of different superlattice periods and unit cell variations. These volume-averaged zero-index superlattice structures present a new type of photonic band gap, with potential for complete wavefront control for arbitrary phase delay lines and open cavity resonances.