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 QCD axion provides a solution to both the strong CP and dark matter problems in the Standard Model. However, the axion solution requires that the gravitational violation of the Peccei-Quinn global symmetry be suppressed to an extremely high …
The axion is a hypothetical particle motivated by the strong CP problem of elementary particle physics and by the dark matter problem of cosmology. Cold dark matter axions are naturally produced during the QCD phase transition in the early universe …