1. Quantum receiver for phase-shift keying at the single photon level
- Author
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Shuro Izumi, Jasminder S. Sidhu, Ulrik L. Andersen, Jonas S. Neergaard-Nielsen, and Cosmo Lupo
- Subjects
Quantum Physics ,Computer science ,Quantum limit ,General Engineering ,Optical communication ,FOS: Physical sciences ,Quantum channel ,Photodetection ,01 natural sciences ,010305 fluids & plasmas ,Quantum state ,0103 physical sciences ,Electronic engineering ,General Earth and Planetary Sciences ,Quantum information ,010306 general physics ,Quantum information science ,Quantum Physics (quant-ph) ,QC ,General Environmental Science ,Phase-shift keying - 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., 11 pages with 10 figures with appendices. Extended analysis. Accepted version
- Published
- 2021