Domino plasmons for subwavelength terahertz circuitry

TL;DR

This paper introduces a novel plasmonic waveguide design for terahertz frequencies, enabling tight electromagnetic confinement and device integration with simple manufacturing, suitable for high-density terahertz circuitry.

Contribution

It presents a new waveguide concept based on periodic metallic structures that maintain mode confinement and low loss in subwavelength regimes, facilitating compact terahertz device integration.

Findings

Dispersion relation is insensitive to waveguide width.

Waveguides support tight confinement with low absorption loss.

Demonstrated devices include tapers, power dividers, and resonators.

Abstract

A new approach for the spatial and temporal modulation of electromagnetic fields at terahertz frequencies is presented. The waveguiding elements are based on plasmonic and metamaterial notions and consist of an easy-to-manufacture periodic chain of metallic box-shaped elements protruding out of a metallic surface. It is shown that the dispersion relation of the corresponding electromagnetic modes is rather insensitive to the waveguide width, preserving tight confinement and reasonable absorption loss even when the waveguide transverse dimensions are well in the subwavelength regime. This property enables the simple implementation of key devices, such as tapers and power dividers. Additionally, directional couplers, waveguide bends, and ring resonators are characterized, demonstrating the flexibility of the proposed concept and the prospects for terahertz applications requiring high integration density.