Abstract
It has been suggested that certain antiferromagnetic topological insulators contain axion quasiparticles (AQs), and that such materials could be used to detect axion dark matter (DM). I review recent progress in this direction. I begin by clarifying the effective theory, and introducing a model for material losses. Current progress on material candidates is discussed, of which there is considerable and rapid progress happening in materials science, especially in China. The DM-AQ resonance mechanism is explained, following the principle of the dielectric haloscope. AQ-photon mixing leads to an effective photon mass near the antiferromagnetic resonance, changing the optical properties of the material, and allowing for resonant axion DM-photon conversion in samples large compared to the axion Compton wavelength. The proposal could allow for detection of axion DM in the mass range between 1 and 10 meV. Once the axion quasiparticle is detected in materials, the main hurdles to dark matter detection will be: losses in the material, and efficient THz photon counters.