Development of high-Q superconducting resonator for DMRadio

QCD axions and axion-like particles are one of the most compelling candidates for Dark Matter. The Dark Matter Radio (DMRadio) is a set of resonantly enhanced electromagnetic searches for axions in the sub-ueV mass window. I will discuss the ongoing research and development project for building a superconducting lumped-element high-Q resonator (>10^6) in the 100 kHz-5 MHz frequency range and understanding the fundamental mechanisms of its losses. This work informs the design and implementation of the resonator for DMRadio-50L in the near term and for DMRadio-GUT in the long term.