Characterization of VUV SiPMs for the nEXO Detector

Evidence of 0νββ decay would imply physics beyond the Standard Model. The tonne-scale nEXO experiment will search for 0νββ decay using a liquid xenon time projection chamber enriched to 90% ¹³⁶Xe. The chamber will be instrumented with vacuum ultraviolet (VUV) silicon photomultipliers (SiPMs) to sense the scintillation light. We present our study of the breakdown voltage of an FBK VUVHD3 SiPM as a linear function of temperature, in the context of the nEXO collaboration. We report our measurements of the breakdown voltage of the SiPM under different environmental conditions, and describe our experimental methodology and its relevance to the search for 0νββ decay.