Retrodiction of single emitter photon emission rates from nanoscale light emitters in random, dynamic systems

Abstract Photon emission in biological and chemical systems often consists of large numbers of moving nanoscale emitters with a high spatial density. Estimating the flux of a single emitter within the ensemble is challenging and can be beyond the limit of current imaging techniques. We introduce a generalised quantum retrodiction technique that estimates the single emitter flux from measurements in complex, dynamic systems. We first experimentally validate this using a solution of fluorescent molecules, and then apply it to a cloud of sonoluminescent bubbles in which the single bubble flux is otherwise unattainable. Our approach provides a quantum-informed experimental determination of single emitter photon emission rates in nanophotonic and photoluminescent systems.