Dielectric Sensing in Epsilon-Near-Zero Narrow Waveguide Channels

TL;DR

This paper leverages supercoupling in epsilon-near-zero ultranarrow waveguides to enhance dielectric sensing capabilities, enabling detection of small permittivity changes with high precision at microwave frequencies.

Contribution

It introduces an analytical model for supercoupling in epsilon-near-zero waveguides and demonstrates their application in high-Q dielectric sensing.

Findings

Analytical expressions describe defect detection in waveguides.

Supercoupling enhances field sensitivity for permittivity variations.

Applications include pass-band tuning and high-Q sensing at microwave frequencies.

Abstract

We exploit here the dramatic field enhancement caused by energy squeezing and tunneling (i.e., 'supercoupling') in metamaterial-inspired ultranarrow waveguide channels with near zero effective permittivity in order to sense small permittivity variations in a tiny object. The supercoupling effect is accurately modeled analytically and closed form expressions are derived to describe the presence of defects or permittivity perturbations along the channel. Applications for tailoring its pass-band frequency and for high-Q sensing are proposed at microwave frequencies.