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arXiv · 1107.0734

Consistent treatment of coherent and incoherent energy transfer dynamics using a variational master equation

Dara P. S. McCutcheon·Ahsan Nazir
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Abstract

We investigate the energy transfer dynamics in a donor-acceptor model by developing a time-local master equation technique based on a variational transformation of the underlying Hamiltonian. The variational transformation allows a minimisation of the Hamiltonian perturbation term dependent on the system parameters, and consequently results in a versatile master equation valid over a range of system-bath coupling strengths, temperatures, and environmental spectral densities. While our formalism reduces to the well-known Redfield, Foerster and polaron forms in the appropriate limits, in general it is not equivalent to perturbing in either the system-environment or donor-acceptor coupling strengths, and hence can provide reliable results between these limits as well. Moreover, we show how to include the effects of both environmental correlations and non-equilibrium preparations within the formalism.

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Dara P. S. McCutcheon, Ahsan Nazir. 2011-09-16. Consistent treatment of coherent and incoherent energy transfer dynamics using a variational master equation. https://doi.org/10.1063/1.3636081

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