Abstract: The goal of future neutrinoless double beta decay experiments is to establish whether the neutrino is its own antiparticle, by searching for an ultrarare decay process with a half-life that may be more than 1027 years. Such a discovery would have major implications for cosmology and particle physics, but it requires ton-scale or larger detectors with backgrounds below 1 counts per ton per year. This is a formidable technological challenge that has prompted consideration of unconventional solutions.
I will discuss an approach being developed within the NEXT collaboration: high-pressure xenon gas time-projection chambers augmented with single-molecule fluorescent imaging-based barium tagging. This approach combines techniques from the fields of biochemistry, super-resolution microscopy, organic synthesis, and nuclear physics, possibly enabling the first effectively background-free, discovery-class neutrinoless double beta decay technology.