Coherence and quantum correlations measure sensitivity to dephasing channels
Quantum Physics
2019-01-23 v2
Abstract
We introduce measures of quantum coherence as the speed of evolution of a system under decoherence. That is, coherence is the ability to estimate a dephasing channel, quantified by the quantum Fisher information. We extend the analysis to interferometric noise estimation, proving that quantum discord is the minimum sensitivity to local dephasing. A physically motivated set of free operations for discord is proposed. The amount of discord created by strictly incoherent operations is upper-bounded by the initial coherence.
Cite
@article{arxiv.1810.02795,
title = {Coherence and quantum correlations measure sensitivity to dephasing channels},
author = {Benjamin Yadin and Pieter Bogaert and Cristian E. Susa and Davide Girolami},
journal= {arXiv preprint arXiv:1810.02795},
year = {2019}
}
Comments
4+2 pages, minor changes, link with previous results clarified