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arXiv · 1311.2045

Competition between memory-keeping and memory-erasing decoherence channels

Tony J. G. Apollaro·Salvatore Lorenzo·Carlo Di Franco·Francesco Plastina·Mauro Paternostro
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Abstract

We study the competing effects of simultaneous Markovian and non-Markovian decoherence mechanisms acting on a single spin. We show the existence of a threshold in the relative strength of such mechanisms above which the spin dynamics becomes fully Markovian, as revealed by the use of several non-Markovianity measures. We identify a measure-dependent nested structure of such thresholds, hinting at a causality relationship amongst the various non-Markovianity witnesses used in our analysis. Our considerations are then used to argue the unavoidably non-Markovian evolution of a single-electron quantum dot exposed to both intrinsic and Markovian technical noise, the latter of arbitrary strength.

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Tony J. G. Apollaro, Salvatore Lorenzo, Carlo Di Franco, Francesco Plastina, Mauro Paternostro. 2013-11-08. Competition between memory-keeping and memory-erasing decoherence channels. https://doi.org/10.1103/physreva.90.012310

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