Frequency-Independent Response of Self-Complementary Checkerboard Screens

TL;DR

This paper demonstrates that self-complementary checkerboard metallic screens exhibit a frequency-independent electromagnetic response over the terahertz range by replacing point contacts with resistive sheets, confirming theoretical predictions.

Contribution

It introduces a novel method to realize frequency-independent responses in checkerboard structures by overcoming contact singularities with resistive sheets, experimentally validating the concept.

Findings

Resistive checkerboard structures show flat transmission from 0.1 to 1.1 THz.

Self-complementarity eliminates frequency-dependent resonances.

Experimental results confirm theoretical predictions of frequency independence.

Abstract

This research resolves a long-standing problem on the electromagnetic response of self-complementary metallic screens with checkerboardlike geometry. Although Babinet's principle implies that they show a frequency-independent response, this unusual characteristic has not been observed yet due to the singularities of the metallic point contacts in the checkerboard geometry. We overcome this difficulty by replacing the point contacts with resistive sheets. The proposed structure is prepared and characterized by terahertz time-domain spectroscopy. It is experimentally confirmed that the resistive checkerboard structures exhibit a flat transmission spectrum over 0.1--1.1 THz. It is also demonstrated that self-complementarity can eliminate even the frequency-dependent transmission characteristics of resonant metamaterials.