Dark matter Axion search with riNg Cavity Experiment DANCE: Design and development of auxiliary cavity for simultaneous resonance of linear polarizations

TL;DR

The paper presents the design and development of an auxiliary cavity for the DANCE experiment to achieve simultaneous resonance of linear polarizations, enhancing the sensitivity in searching for axion-like particles as dark matter candidates.

Contribution

It introduces a novel auxiliary cavity design to cancel resonant frequency differences, enabling simultaneous polarization resonance in the DANCE experiment.

Findings

The auxiliary cavity can effectively cancel frequency differences.

Sensitivity with the auxiliary cavity matches the original target.

Prototype experiments confirm improved resonance conditions.

Abstract

Axion-like particles (ALPs) are undiscovered pseudo-scalar particles that are candidates for ultralight dark matter. ALPs interact with photons slightly and cause the rotational oscillation of linearly polarized light. Dark matter Axion search with riNg Cavity Experiment (DANCE) searches for ALP dark matter by amplifying the rotational oscillation with a bow-tie ring cavity. Simultaneous resonance of linear polarizations is necessary to amplify both the carrier field and the ALP signal, and to achieve the design sensitivity. The sensitivity of the current prototype experiment DANCE Act-1 is less than expectation by around three orders of magnitude due to the resonant frequency difference between s- and p-polarization in the bow-tie ring cavity. In order to tune the resonant frequency difference, the method of introducing an auxiliary cavity was proposed. We designed an auxiliary cavity that can cancel out the resonant frequency difference and realize simultaneous resonance, considering optical loss. We also confirmed that the sensitivity of DANCE Act-1 with the auxiliary cavity can reach the original sensitivity.