Axion Detection with Optomechanical Cavities

TL;DR

This paper introduces a new optomechanical cavity method using superfluid helium to detect axions by converting laser photons into photons and phonons, enabling exploration of a broad axion mass range.

Contribution

It presents a novel cavity-based technique for axion detection that overcomes small coupling issues and allows scalable searches across a wide mass spectrum.

Findings

Enhanced axion absorption rate via high photon/phonon occupation

Ability to probe axion masses up to 1 meV

Scalable cavity design independent of axion mass

Abstract

We propose a novel technique to search for axions with an optomechanical cavity filled with a material such as superfluid helium. Axion absorption converts a pump laser photon to a photon plus a phonon. The axion absorption rate is enhanced by the high occupation number of coherent photons or phonons in the cavity, allowing our proposal to largely overcome the extremely small axion coupling. The axion mass probed is set by the relative frequency of the photon produced in the final state and the Stokes mode. Because neither the axion mass nor momentum need to be matched to the physical size of the cavity, we can scale up the cavity size while maintaining access to a wide range of axion masses (up to a meV) complementary to other cavity proposals.