Sample-efficient adaptive calibration of quantum networks using Bayesian optimization

TL;DR

This paper introduces resource-efficient Bayesian optimization methods to quickly calibrate photon indistinguishability in quantum networks, improving performance in noisy, lossy environments for quantum communication and computing.

Contribution

It develops and experimentally validates a Bayesian optimization approach for rapid, resource-efficient calibration of photon indistinguishability in quantum networks.

Findings

Achieved rapid convergence to maximal photon indistinguishability.

Demonstrated robustness under high loss and shot noise conditions.

Validated effectiveness in optimizing Hong-Ou-Mandel interference.

Abstract

Indistinguishable photons are imperative for advanced quantum communication networks. Indistinguishability is difficult to obtain because of environment-induced photon transformations and loss imparted by communication channels, especially in noisy scenarios. Strategies to mitigate these transformations often require hardware or software overhead that is restrictive (e.g. adding noise), infeasible (e.g. on a satellite), or time-consuming for deployed networks. Here we propose and develop resource-efficient Bayesian optimization techniques to rapidly and adaptively calibrate the indistinguishability of individual photons for quantum networks using only information derived from their measurement. To experimentally validate our approach, we demonstrate the optimization of Hong-Ou-Mandel interference between two photons -- a central task in quantum networking -- finding rapid, efficient, and reliable convergence towards maximal photon indistinguishability in the presence of high loss and shot noise. We expect our resource-optimized and experimentally friendly methodology will allow fast and reliable calibration of indistinguishable quanta, a necessary task in distributed quantum computing, communications, and sensing, as well as for fundamental investigations.