Exact stochastic unraveling of an optical coherence dynamics by cumulant expansion.

  title={Exact stochastic unraveling of an optical coherence dynamics by cumulant expansion.},
  author={Jan Ol{\vs}ina and Tobias Kramer and Christoph Kreisbeck and Tom{\'a}{\vs} Man{\vc}al},
  journal={The Journal of chemical physics},
  volume={141 16},
A numerically exact Monte Carlo scheme for calculation of open quantum system dynamics is proposed and implemented. The method consists of a Monte Carlo summation of a perturbation expansion in terms of trajectories in Liouville phase-space with respect to the coupling between the excited states of the molecule. The trajectories are weighted by a complex decoherence factor based on the second-order cumulant expansion of the environmental evolution. The method can be used with an arbitrary… 
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