Discovery of Bragg confined hybrid modes with high Q-factor in a hollow dielectric resonator

TL;DR

This paper reports the discovery of high-Q Bragg confined hybrid modes in a hollow dielectric resonator, demonstrating modes with non-zero azimuthal variations and significantly improved quality factors over previous modes.

Contribution

The study reveals the existence of hybrid Bragg confined modes with high Q-factors in hollow dielectric resonators, expanding the understanding of mode confinement beyond pure TE modes.

Findings

Resonance at 13.4 GHz with Q-factor of 2×10^5

Modes exhibit non-zero azimuthal variations and hybrid electric field components

Q-factor exceeds dielectric loss limit by over six times

Abstract

The authors report on observation of Bragg confined mode in a hollow cylindrical dielectric cavity. A resonance was observed at 13.4 $GHz$ with an unloaded Q-factor of order $2\times10^5$, which is more than a factor of 6 above the dielectric loss limit. Previously such modes have only been realized from pure Transverse Electric modes with no azimuthal variations and only the $E_{\phi}$ component. From rigorous numeric simulations it is shown that the mode is a hybrid mode with non-zero azimuthal variations and with dominant $E_r$ and $E_{\phi}$ electric field components and $H_z$ magnetic field component.