arXiv:1803.06844 · New Journal of Physics

Revealing memory effects in phase-covariant quantum master equations

J Teittinen, H Lyyra, B Sokolov, Sabrina Maniscalco

Published Jun 15, 2018• 39 citations

Abstract

We study and compare the sensitivity of multiple non-Markovianity indicators for a qubit subjected to general phase-covariant noise. For each of the indicators, we derive analytical conditions to detect the dynamics as non-Markovian. We present these conditions as relations between the time-dependent decay rates for the general open system dynamics and its commutative and unital subclasses. These relations tell directly if the dynamics is non-Markovian w.r.t. each indicator, without the need to explicitly derive and specify the analytic form of the time-dependent coefficients. Moreover, with a shift in perspective, we show that if one assumes only the general form of the master equation, measuring the non-Markovianity indicators gives us directly non-trivial information on the relations between the unknown decay rates.

DOI: 10.1088/1367-2630/aacc38

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