Microwave limiters implemented by coupled dielectric resonators based on a topological defect mode and CT-symmetry breaking

TL;DR

This paper demonstrates a microwave topological limiter using coupled dielectric resonators that exploit CT-symmetry breaking to control transmittance and reflectance, offering a new approach to microwave protection devices.

Contribution

It introduces a novel topological microwave limiter based on a self-induced CT-symmetry violation in coupled dielectric resonators with a defect mode.

Findings

High irradiance causes CT-symmetry breaking.

Transmittance is suppressed while reflectance increases.

Absorption remains low during operation.

Abstract

We present a microwave realization of a reflective topological limiter based on an explicit self-induced violation of a charge-conjugation (CT) symmetry. The starting point is a bipartite structure created by coupled dielectric resonators with a topological defect placed at the center and two lossy resonators placed on the neighboring sites of the defect. This defect supports a resonant mode if the CT-symmetry is present, while it is suppressed once the symmetry is violated due to permittivity changes of the defect resonator associated with high irradiances of the incident radiation. This destruction leads to a suppression of transmittance and a subsequent increase of the reflectance while the absorption is also suppressed.