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arXiv · 1511.07202

Complete positivity, finite temperature effects, and additivity of noise for time-local qubit dynamics

Juho Lankinen·Henri Lyyra·Boris Sokolov·Jose Teittinen·Babak Ziaei·Sabrina Maniscalco
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Abstract

We present a general model of qubit dynamics which entails pure dephasing and dissipative time-local master equations. This allows us to describe the combined effect of thermalisation and dephasing beyond the usual Markovian approximation. We investigate the complete positivity conditions and introduce a heuristic model that is always physical and provides the correct Markovian limit. We study the effects of temperature on the non-Markovian behaviour of the system and show that the noise additivity property discussed by Yu and Eberly in Ref. [1] holds beyond the Markovian limit.

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Juho Lankinen, Henri Lyyra, Boris Sokolov, Jose Teittinen, Babak Ziaei, Sabrina Maniscalco. 2015-11-23. Complete positivity, finite temperature effects, and additivity of noise for time-local qubit dynamics. https://doi.org/10.1103/physreva.93.052103

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