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arXiv · 2303.18207

Quantum Illumination with a Hetero-Homodyne Receiver and Sequential Detection

Maximilian Reichert·Quntao Zhuang·Jeffrey H. Shapiro·Roberto Di Candia
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Abstract

We propose a hetero-homodyne receiver for quantum illumination (QI) target detection. Unlike prior QI receivers, it uses a cascaded positive operator-valued measurement (POVM) that does not require a quantum interaction between QI's returned radiation and its stored idler. When used without sequential detection its performance matches the 3 dB quantum advantage over optimum classical illumination (CI) that Guha and Erkmen's [Phys. Rev. A 80, 052310 (2009)] phase-conjugate and parametric amplifier receivers enjoy. When used in a sequential detection QI protocol, the hetero-homodyne receiver offers a 9 dB quantum advantage over a conventional CI radar, and a 3 dB advantage over a CI radar with sequential detection. Our work is a significant step forward toward a practical quantum radar for the microwave region, and, more generally, emphasizes the potential offered by cascaded POVMs for quantum radar.

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Maximilian Reichert, Quntao Zhuang, Jeffrey H. Shapiro, Roberto Di Candia. 2023-03-31. Quantum Illumination with a Hetero-Homodyne Receiver and Sequential Detection. https://doi.org/10.1103/physrevapplied.20.014030

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