2020/09/30 by Jasminder S. Sidhu, Shuro Izumi, Jonas S. Neergaard-Nielsen +2
Computer Science · Engineering · Physics and Astronomy · #Decoding methods #Detector #Keying #Limit (mathematics) #Optical Network Technologies #Preamble #Quantum #Quantum Information and Cryptography #Quantum limit #Quantum optics and atomic interactions #Topology (electrical circuits) #Transmission (telecommunications) #quant-ph
paper · pdf · doi:10.1103/prxquantum.2.010332
published as PRX Quantum 2, 010332 (2021) · 11 pages with 10 figures with appendices. Extended analysis. Accepted version
arxiv created 2021/01/31 · openalex created_date 2021/02/15 · openalex publication_date 2021/02/26 · arxiv updated 2021/03/03 · openalex updated_date 2026/08/05
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 nonorthogonal 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 nonadaptive detectors at low input powers. Unlike existing approaches, the receiver only exploits linear optical elements and on-off photodetection. This circumvents the requirement for challenging feed-forward operations that limit communication transmission rates and can be readily implemented with current technology.