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arXiv · 0905.1020

Completely Positive Markovian Quantum Dynamics in the Weak-Coupling Limit

David Taj·Fausto Rossi
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Abstract

We obtain new types of exponential decay laws for solutions of density-matrix master equations in the weak-coupling limit: after comparing with results already present in the literature and developing the necessary techniques, we study the crucial aspect of complete positivity under fairly general conditions. We propose a new type of time average that guarantees complete positivity and approximates, in markovian fashion, the exact dynamics for a plethora of physical applications, no matter which are the spectral properties of the subsystem, or its dimensions. We shall comment on some interesting examples, like a new Quantum version of the celebrated Fermi's Golden Rule and some recently proposed entangling projections.

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David Taj, Fausto Rossi. 2009-05-07. Completely Positive Markovian Quantum Dynamics in the Weak-Coupling Limit. https://doi.org/10.1103/physreva.78.052113

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