Variable group delay in a metamaterial with field-gradient-induced transparency

TL;DR

This paper demonstrates a metamaterial that allows dynamic control of microwave pulse delay by adjusting the incident angle, leveraging field-gradient-induced transparency to tune group delay.

Contribution

The study introduces a metamaterial design where the coupling between modes is controlled by electromagnetic field gradients, enabling variable group delay.

Findings

Group delay can be tuned from 0.50 to 1.85 ns.

The metamaterial's transparency is controlled by incident angle.

Field-gradient-induced transparency enables dynamic delay control.

Abstract

We realize variable control of the group delay in an electromagnetically induced transparency-like metamaterial. Its unit cell is designed to have a bright mode and a dark mode. The coupling strength between these two modes is determined by the electromagnetic field gradient. In this metamaterial with field-gradient-induced transparency, the group delay at the transparency frequency can be varied by varying the incident angle of the electromagnetic plane waves. By tilting a single layer of the metamaterial, the group delay of a microwave pulse can be varied between 0.50 and 1.85 ns.