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arXiv · 2009.03339

Quantum receiver for phase-shift keying at the single photon level

Jasminder S. Sidhu·Shuro Izumi·Jonas S. Neergaard-Nielsen·Cosmo Lupo·Ulrik L. Andersen
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Abstract

Quantum enhanced receivers are endowed with resources to achieve higher sensitivities than conventional technologies. For application in optical communications, they provide improved discriminatory capabilities for multiple non-orthogonal quantum states. In this work, we propose and experimentally demonstrate a new decoding scheme for quadrature phase-shift encoded signals. Our receiver surpasses the standard quantum limit and outperforms all previously known non-adaptive detectors at low input powers. Unlike existing approaches, the receiver only exploits linear optical elements and on-off photo-detection. This circumvents the requirement for challenging feed-forward operations that limit communication transmission rates and can be readily implemented with current technology.

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Jasminder S. Sidhu, Shuro Izumi, Jonas S. Neergaard-Nielsen, Cosmo Lupo, Ulrik L. Andersen. 2020-09-07. Quantum receiver for phase-shift keying at the single photon level. https://doi.org/10.1103/prxquantum.2.010332

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