Analog electromagnetically induced transparency for circularly polarized wave using three dimensional chiral metamaterials

TL;DR

This paper demonstrates a 3D chiral metamaterial that exhibits electromagnetically induced transparency for circularly polarized waves, with potential applications in slow light devices, through theoretical and experimental analysis.

Contribution

It introduces a novel 3D chiral metamaterial design that achieves EIT for circular polarization, analyzed with coupled oscillator and circuit models.

Findings

EIT window is achieved for right circular polarization.

The transparency window's amplitude and frequency are tunable.

The structure shows potential for chiral slow light applications.

Abstract

In this paper, we theoretically and experimentally demonstrate a three dimensional metamaterial that can motivate electromagnetic induced transparency (EIT) by using circular polarized wave as stimulations. The unit cell consists of a pair of metallic strips printed on both sides of the printed circuit board (PCB), where a conductive cylinder junction is used to connect the metal strips by drilling a hole inside the substrate. When a right circularly polarized wave is incident, destructive interference is excited between meta-atoms of the 3D structure, the transmission spectrum demonstrates a sharp transparency window. A coupled oscillator model and an electrical equivalent circuit model are applied to quantitatively and qualitatively analyze the coupling mechanism in the EIT-like metamaterial. Analysis in detail shows the EIT window's amplitude and frequency are modulated by changing the degree of symmetry breaking. The proposed metamaterial may achieve potential applications in developing chiral slow light devices.