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Title: Experimental demonstration of the near-quantum optimal receiver

We implement the cyclic quantum receiver based on the theoretical proposal of Roy Bondurant and demonstrate experimentally below the shot-noise limit (SNL) discrimination of quadrature phase-shift keying signals (PSK). We also experimentally test the receiver generalized for longer communication alphabet lengths and coherent frequency shift keying (CFSK) encoding. Using off-the-shelf components, we obtain state discrimination error rates that are 3 dB and 4.6 dB below the SNLs of ideal classical receivers for quadrature PSK and CFSK encodings, respectively. The receiver unconditionally surpasses the SNL for M=8 PSK and CFSK. This receiver can be used for the simple and robust practical implementation of quantum-enhanced optical communication.

 
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Award ID(s):
1927674
NSF-PAR ID:
10202454
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
OSA Continuum
Volume:
3
Issue:
12
ISSN:
2578-7519
Format(s):
Medium: X Size: Article No. 3324
Size(s):
Article No. 3324
Sponsoring Org:
National Science Foundation
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