Comment on "Axion-matter coupling in multiferroics"

Abstract

A previous publication [H. S. Roising et al., Phys. Rev. Research 3, 033236 (2021)] involving the current authors pointed out a coupling between dark matter axions and ferroic orders in multiferroics. In this comment we argue that using this coupling for dark matter sensing is likely not feasible for the material class we considered, with present-day technologies and level of materials synthesis. The proposed effect (for QCD axions) is small and is overwhelmed by thermal noise. This finding means that likely materials for the proposed detection scheme would need to be found with significantly lower magnetic ordering temperatures.