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arXiv · 2111.02975

Approximating Invertible Maps by Recovery Channels: Optimality and an Application to Non-Markovian Dynamics

Lea Lautenbacher·Fernando de Melo·Nadja K. Bernardes
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Abstract

We investigate the problem of reversing quantum dynamics, specifically via optimal Petz recovery maps. We focus on typical decoherence channels, such as dephasing, depolarizing and amplitude damping. We illustrate how well a physically implementable recovery map simulates an inverse evolution. We extend this idea to explore the use of recovery maps as an approximation of inverse maps, and apply it in the context of non-Markovian dynamics. We show how this strategy attenuates non-Markovian effects, such as the backflow of information.

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Lea Lautenbacher, Fernando de Melo, Nadja K. Bernardes. 2021-11-04. Approximating Invertible Maps by Recovery Channels: Optimality and an Application to Non-Markovian Dynamics. https://doi.org/10.1103/physreva.105.042421

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