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arXiv · 2108.08573

Optimal squeezing for quantum target detection

Gaetana Spedalieri·Stefano Pirandola
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Abstract

It is not clear if the performance of a quantum lidar or radar, without an idler and only using Gaussian resources, could exceed the performance of a semiclassical setup based on coherent states and homodyne detection. Here we prove this is indeed the case by showing that an idler-free squeezed-based setup can beat this semiclassical benchmark. More generally, we show that probes whose displacement and squeezing are jointly optimized can strictly outperform coherent states with the same mean number of input photons for both the problems of quantum illumination and reading.

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Gaetana Spedalieri, Stefano Pirandola. 2021-08-19. Optimal squeezing for quantum target detection. https://doi.org/10.1103/physrevresearch.3.l042039

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