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arXiv · 1612.04625

Non-Markovianity Quantifier of an Arbitrary Quantum Process

Tiago Debarba·Felipe F. Fanchini
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Abstract

Calculating the degree of non-Markovianity of a dissipative process is a difficult task, even for the dynamics of a single qubit, given the complex maximization problem. In this work, focusing on the entanglement-based quantifier of non-Markovianity, we present an analytical solution for such an optimization problem. We then propose a computable non-Markovianity measure based on generalized robustness of entanglement, an entanglement measure that can be readily calculated by a semidefinite programming method. We show that the non-Markovianity, in a given interval of time, can be witnessed by calculating the expectation value of an observable, making it attractive for experimental investigations.

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Tiago Debarba, Felipe F. Fanchini. 2016-12-14. Non-Markovianity Quantifier of an Arbitrary Quantum Process. https://doi.org/10.1103/physreva.96.062118

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