NV-Center Readout of Superconducting Bolometer Pixels: Optical Transduction of Meissner Screening

We propose and demonstrate a hybrid particle detection scheme utilizing nitrogen-vacancy (NV) center magnetometry to probe magnetic field exclusion in superconducting thin-films undergoing phase transition as a result of particle energy depositions. A modular Python-COMSOL workflow simulates localized energy depositions, Meissner screening collapse, and subsequently NV fluorescence response. The model utilizes experimentally informed noise and readout timing information to predict the energy resolution achievable with such a setup. Additionally, we report experimental demonstration of the NV-center based readout of Meissner screening using a diamond sample positioned above a Niobium-Nitride thin film in a simplified widefield optical setup. This work represents the first step toward a hybrid NV–superconductor detector capable of resolving low-energy events for future quantum sensing and calorimetry applications.