Limits of the time-multiplexed photon-counting method
Regina Kruse, Johannes Tiedau, Tim J. Bartley, Sonja Barkhofen, Christine Silberhorn · Physical Review A · 2017
The progress in building large quantum states and networks requires sophisticated detection techniques to verify the desired operation. To achieve this aim, a cost- and resource-efficient detection method is the time multiplexing of photonic states. This design is assumed to be efficiently scalable; however, it is restricted by inevitable losses and limited detection efficiencies. Here, we investigate the scalability of time-multiplexed detectors under the effects of fiber dispersion and losses. We use the distinguishability of Fock states up to $n=20$ after passing the time-multiplexed detector as our figure of merit and find that, for realistic setup efficiencies of $\ensuremath{\eta}=0.85$, the optimal size for time-multiplexed detectors is 256 bins.