Axion Dark Matter
  Axions are well-motivated dark matter candidates with simple cosmological
production mechanisms. They were originally introduced to solve the strong CP
problem, but also arise in a wide range of extensions to the Standard Model.
This Snowmass white paper summarizes axion phenomenology and outlines
next-generation laboratory experiments proposed to detect axion dark matter.
There are vibrant synergies with astrophysical searches and advances in
instrumentation including quantum-enabled readout, high-Q resonators and
cavities and large high-field magnets. This white paper outlines a clear
roadmap to discovery, and shows that the US is well-positioned to be at the
forefront of the search for axion dark matter in the coming decade.
