English

Noise is resource-contextual in quantum communication

Quantum Physics 2024-07-26 v3 Information Theory math.IT

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.

Keywords

Cite

@article{arxiv.2305.00680,
  title  = {Noise is resource-contextual in quantum communication},
  author = {Aditya Nema and Ananda G. Maity and Sergii Strelchuk and David Elkouss},
  journal= {arXiv preprint arXiv:2305.00680},
  year   = {2024}
}

Comments

16 pages, 6 figures, Updated with additional and elaborated references. Sincere, thanks to Felix Leditzky and Stefano Pirandola for pointing out the appropriate references. Added note on general applicability of results

R2 v1 2026-06-28T10:22:16.052Z