Abstract: Sensitivity gaps in the search for keV-MeV mass dark matter exist in both direct and indirect detection experiments. For direct detection, this gap can be closed by utilising new and rapidly developing quantum sensing technologies. I will discuss (i) single quantum detection using magnetic avalanches in chemical crystals and its application to the dark matter search, and (ii) novel features of the theoretical calculations necessary to describe the interaction of sub-MeV dark matter with quanta of the collective modes of a detector material.