Optimizing Thermal Detectors for Low-Threshold Applications in Neutrino and Dark Matter Experiments

Nuclear recoil detectors with low energy thresholds of 10–100 eV have applications in both neutrino physics (e.g. coherent elastic neutrino-nucleus scattering and neutrinoless double beta decay) as well as for O(GeV)-mass dark matter searches. Cryogenic crystal detectors are well suited for these applications, although some require very large masses which can be achieved with arrays of these detectors. An optimization of a design focusing on ease of fabrication and mass production while retaining low energy thresholds is presented. This is achieved by decoupling the complex lithography of the thermal sensor from the large crystal absorber/target, while optimizing the thermal time constants to retain the lowest threshold possible.