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arXiv:2412.04779 · Physical Review A

Nonlocality-assisted enhancement of error-free communication in noisy classical channels

Kunika Agarwal, Sahil Gopalkrishna Naik, Ananya Chakraborty, Samrat Sen, Pratik Ghosal, Biswajit Paul, Manik Banik, Ram Krishna Patra

Published Mar 10, 2026• 0 citations
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Abstract

The zero-error capacity of a noisy classical channel quantifies its ability to transmit information with absolute certainty, i.e., without any error. Unlike Shannon's standard channel capacity, which remains unaffected by pre-shared correlations, zero-error capacity can be enhanced through nonlocal correlations. In this work, we investigate zero-error communication utility of such correlations arising in the 2-2-m Bell scenario, where two parties have two inputs and m possible outcomes per input. For all m\geq2, we construct examples of noisy classical channels with zero zero-error capacity that, when assisted by extremal 2-2-m nonlocal correlations, can transmit one bit of information. While nonlocal correlations arising from quantum entangled states cannot achieve a positive zero-error capacity for these channels, they significantly enhance the probability of successfully transmitting a classical bit in a single use. Extending this analysis to the 2-m-2 Bell scenario, we identify channels with zero zero-error capacity that can nonetheless perfectly transmit log m bits of information when assisted by corresponding extremal nonlocal correlations. Our findings underscore the versatile utility of Bell nonlocal correlations in achieving zero-error communication.

DOI
10.1103/dsdj-dz8l

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