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arXiv · 0707.3938

On the conundrum of deriving exact solutions from approximate master equations

Roland Doll·David Zueco·Martijn Wubs·Sigmund Kohler·Peter Hanggi
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Abstract

We derive the exact time-evolution for a general quantum system under the influence of pure phase-noise and demonstrate that for a Gaussian initial state of the bath, the exact result can be obtained also within a perturbative time-local master equation approach already in second order of the system-bath coupling strength. We reveal that this equivalence holds if the initial state of the bath can be mapped to a Gaussian phase-space distribution function. Moreover, we discuss the relation to the standard Bloch-Redfield approach.

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Roland Doll, David Zueco, Martijn Wubs, Sigmund Kohler, Peter Hanggi. 2007-09-05. On the conundrum of deriving exact solutions from approximate master equations. https://doi.org/10.1016/j.chemphys.2007.09.003

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