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arXiv · 2410.21800

Photonic Quantum Receiver Attaining the Helstrom Bound

Aakash Warke·Janis Nötzel·Kan Takase·Warit Asavanant·Hironari Nagayoshi·Kosuke Fukui·Shuntaro Takeda·Akira Furusawa·Peter van Loock
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Abstract

We propose an efficient decomposition scheme for a quantum receiver that attains the Helstrom bound in the low-photon regime for discriminating binary coherent states. Our method, which avoids feedback as used in Dolinar's case, breaks down nonlinear operations into basic gates used in continuous-variable quantum computation. We account for realistic conditions by examining the impact of photon loss and imperfect photon detection, including the presence of dark counts, while presenting squeezing as a technique to mitigate these noise sources and maintain the advantage over SQL. Our scheme motivates testing quantum advantages with cubic-phase gates and designing photonic quantum computers to optimize symbol-by-symbol measurements in optical communication.

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Aakash Warke, Janis Nötzel, Kan Takase, Warit Asavanant, Hironari Nagayoshi, Kosuke Fukui, Shuntaro Takeda, Akira Furusawa, Peter van Loock. 2024-10-29. Photonic Quantum Receiver Attaining the Helstrom Bound. https://arxiv.org/abs/2410.21800

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