A triple trade-off capacity region of a noisy quantum channel provides a more complete description of its capabilities than does a single capacity formula. However, few full descriptions of a channels ability have been given due to the difficult nature of the calculation of such regionsit may demand an optimization of information-theoretic quantities over an infinite number of channel uses. This work analyses the d-dimensional Unruh channel, a noisy quantum channel which emerges in relativistic quantum information theory. We show that this channel belongs to the class of quantum channels whose capacity region requires an optimization over a single channel use, and as such is tractable. We determine two triple-trade off regions, the quantum dynamic capacity region and the private dynamic capacity region, of the d-dimensional Unruh channel. Our results show that the set of achievable rate triples using this coding strategy is larger than the set achieved using a time-sharing strategy. Furthermore, we prove that the Unruh channel has a distinct structure made up of universal qudit cloning channels, thus providing a clear relationship between this relativistic channel and the process of stimulated emission present in quantum optical amplifiers. © 2011 IOP Publishing Ltd.
Publication Source (Journal or Book title)
Journal of Physics A: Mathematical and Theoretical
Jochym-O'Connor, T., Brádler, K., & Wilde, M. (2011). Trade-off coding for universal qudit cloners motivated by the Unruh effect. Journal of Physics A: Mathematical and Theoretical, 44 (41) https://doi.org/10.1088/1751-8113/44/41/415306