arXiv:2305.00680 · Physical Review Research

Noise is resource-contextual in quantum communication

Aditya Nema, Ananda G. Maity, Sergii Strelchuk, David Elkouss

Published Jul 19, 2024• 1 citation

Abstract

Estimating the information transmission capability of a quantum channel remains one of the fundamental problems in quantum information processing. In contrast to classical channels, the information-carrying capability of quantum channels is contextual. One of the most significant manifestations of this is the superadditivity of the channel capacity: the capacity of two quantum channels used together can be larger than the sum of the individual capacities. Here, we present a one-parameter family of channels for which, as the parameter increases, its one-way quantum and private capacities increase while its two-way capacities decrease. We also exhibit a one-parameter family of states with analogous behavior with respect to the one- and two-way distillable entanglement and secret key. Our constructions demonstrate that noise is context dependent in quantum communication. Published by the American Physical Society 2024

DOI: 10.1103/physrevresearch.6.033089

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