Prospects for Axion Dark Matter Searches at LISA-like Interferometers

TL;DR

This paper proposes a method for space-based laser interferometers like LISA to detect axion dark matter by observing birefringence effects on laser polarization, potentially probing axion-photon couplings in a specific mass range.

Contribution

It introduces a novel modification to LISA-like interferometers to enhance sensitivity to axion-induced birefringence effects, expanding dark matter detection capabilities.

Findings

Next-generation space interferometers can detect axion-photon couplings.

Sensitivity is promising for axion masses around 10^{-19} to 10^{-14} eV.

The method leverages Sagnac combinations to identify birefringence signals.

Abstract

Axion or axionlike particles are one of the leading candidates for dark matter. Because of its tiny coupling with photons, axion dark matter in the background can induce distinct phase velocities for light with different parity, an effect known as birefringence. Here, we propose a modification to the polarization state of the interspacecraft laser link in LISA-like interferometers to make them sensitive to this birefringence effect. We discuss the prospects of using the Sagnac combinations to search for axion dark matter and derive the corresponding sensitivity. With this setup, we show that next-generation laser interferometers in space would have promising sensitivities on the axion-photon coupling with axion mass around $10^{-19} - 10^{-14}~\text{eV}$.