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arXiv · 1203.6469

Time Invariant Discord and Non-Markovianity

Pinja Haikka·Tomi H. Johnson·Sabrina Maniscalco
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Abstract

We study non-Markovianity and information flow for qubits experiencing local dephasing with an Ohmic class spectrum. We demonstrate the existence of a temperature-dependent critical value of the Ohmicity parameter s for the onset of non-Markovianity and give a physical interpretation of this phenomenon by linking it to the form of the reservoir spectrum. We demonstrate that this link holds also for more general spectra. We unveil a class of initial states for which discord is forever frozen at a positive value. We connect time invariant discord to non-Markovianity and propose a physical system in which it could be observed.

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Pinja Haikka, Tomi H. Johnson, Sabrina Maniscalco. 2012-03-29. Time Invariant Discord and Non-Markovianity. https://arxiv.org/abs/1203.6469

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