Superconducting cavity in CAPP's dark matter axion experiment

The IBS Center for Axion and Precision Physics Research (CAPP) in Korea searches for axions using a tunable resonant cavity to enhance axion to photon conversion rates to a detectable level when the cavity resonates at the axion mass. The superconducting coat on the inner surface of the cavity could raise the Q-factor significantly, among other possible improvements to enhance the sensitivity of the experiment, but the presence of the high magnetic field prevents it since the type I superconductor loses superconductivity easily even with a small amount of field. I will present the results of measuring Q-factors of the cavity by coating NbTi with RF magnetron sputtering method and applying YBCO tapes to the inner surface of the cavity.