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arXiv · 1910.05089

Accessible coherence in open quantum system dynamics

María García Díaz·Benjamin Desef·Matteo Rosati·Dario Egloff·John Calsamiglia·Andrea Smirne·Michaelis Skotiniotis·Susana F. Huelga
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Abstract

Quantum coherence generated in a physical process can only be cast as a potentially useful resource if its effects can be detected at a later time. Recently, the notion of non-coherence-generating-and-detecting (NCGD) dynamics has been introduced and related to the classicality of the statistics associated with sequential measurements at different times. However, in order for a dynamics to be NCGD, its propagators need to satisfy a given set of conditions for all triples of consecutive times. We reduce this to a finite set of $d(d-1)$ conditions, where $d$ is the dimension of the quantum system, provided that the generator is time-independent. Further conditions are derived for the more general time-dependent case. The application of this result to the case of a qubit dynamics allows us to elucidate which kind of noise gives rise to non-coherence-generation-and-detection.

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María García Díaz, Benjamin Desef, Matteo Rosati, Dario Egloff, John Calsamiglia, Andrea Smirne, Michaelis Skotiniotis, Susana F. Huelga. 2019-10-11. Accessible coherence in open quantum system dynamics. https://doi.org/10.22331/q-2020-04-02-249

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