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arXiv · 2004.11208

Hierarchy of quantum correlations under non-Markovian dynamics

K. G Paulson·Ekta Panwar·Subhashish Banerjee·R. Srikanth
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Abstract

We investigate the dynamics of quantum correlations (QC) under the effects of reservoir memory, as a resource for quantum information and computation tasks. Quantum correlations of two-qubit systems are used for implementing quantum teleportation successfully, and for investigating how teleportation fidelity, violation of Bell-CHSH inequality, quantum steering and entanglement are connected with each other under the influence of noisy environments. Both Markovian and non-Markovian channels are considered, and it is shown that the decay and revival of correlations follow the hierarchy of quantum correlations in the state space. Noise tolerance of quantum correlations are checked for different types of unital and non-unital quantum channels, with and without memory. The quantum speed limit time $(\tau_{QSL})$ is investigated from the perspective of memory of quantum noise, and the corresponding dynamics is used to analyze the evolution of quantum correlations. We establish the connection between information backflow, quantum speed limit time and dynamics of quantum correlations for non-Markovian quantum channels.

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K. G Paulson, Ekta Panwar, Subhashish Banerjee, R. Srikanth. 2020-04-21. Hierarchy of quantum correlations under non-Markovian dynamics. https://doi.org/10.1007/s11128-021-03061-9

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