Search for Cosmic Axions using an Optical Interferometer
  A high finesse optical cavity can be used to search for cosmic axions in the mass range 10^{-6}< m_a <10^{-4} eV. Either a two-arm or a single-arm cavity is suitable and in either case the signal as resonant sidebands imposed on the carrier. Assuming for the local axion density the usual figure of 500 MeV/cm^3 [8], the KSVZ axion line [4] g/m_a = 0.4 Gev^{-2}, can be reached over the full mass range in a one year search. 
Adrian C. Melissinos