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arXiv · 2108.03755

Optimal control of coherent light scattering for binary decision problems

Dorian Bouchet·Lukas M. Rachbauer·Stefan Rotter·Allard P. Mosk·Emmanuel Bossy
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Abstract

Due to quantum noise fluctuations, the rate of error achievable in decision problems involving several possible configurations of a scattering system is subject to a fundamental limit known as the Helstrom bound. Here, we present a general framework to calculate and minimize this bound using coherent probe fields with tailored spatial distributions. As an example, we experimentally study a target located in between two disordered scattering media. We first show that the optimal field distribution can be directly identified using a general approach based on scattering matrix measurements. We then demonstrate that this optimal light field successfully probes the presence of the target with a number of photons that is reduced by more than two orders of magnitude as compared to unoptimized fields.

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Dorian Bouchet, Lukas M. Rachbauer, Stefan Rotter, Allard P. Mosk, Emmanuel Bossy. 2021-08-08. Optimal control of coherent light scattering for binary decision problems. https://doi.org/10.1103/physrevlett.127.253902

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