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arXiv · 1810.02795

Coherence and quantum correlations measure sensitivity to dephasing channels

Benjamin Yadin·Pieter Bogaert·Cristian E. Susa·Davide Girolami
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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.

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Benjamin Yadin, Pieter Bogaert, Cristian E. Susa, Davide Girolami. 2018-10-05. Coherence and quantum correlations measure sensitivity to dephasing channels. https://doi.org/10.1103/physreva.99.012329

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