Accuracy assessment of perturbative master equations: Embracing nonpositivity

@article{Hartmann2020AccuracyAO,
  title={Accuracy assessment of perturbative master equations: Embracing nonpositivity},
  author={Richard Hartmann and Walter T. Strunz},
  journal={Physical Review A},
  year={2020}
}
The reduced dynamics of an open quantum system obtained from an underlying microscopic Hamiltonian can in general only approximately be described by a time local master equation. The quality of that approximation depends primarily on the coupling strength and the structure of the environment. Various such master equations have been proposed with different aims. Choosing the most suitable one for a specific system is not straight forward. By focusing on the accuracy of the reduced dynamics we… 
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