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Perturbative treatment of intercenter coupling in Redfield theory

Ulrich Kleinekathoefer·Ivan Kondov·Michael Schreiber
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Abstract

The quantum dynamics of coupled subsystems connected to a thermal bath is studied. In some of the earlier work the effect of intercenter coupling on the dissipative part was neglected. This is equivalent to a zeroth-order perturbative expansion of the damping term with respect to the intercenter coupling. It is shown numerically for two coupled harmonic oscillators that this treatment can lead to artifacts and a completely wrong description, for example, of a charge transfer processes even for very weak intercenter coupling. Here we perform a first-order treatment and show that these artifacts disappear. In addition, we demonstrate that the thermodynamic equilibrium population is almost reached even for strong intercenter coupling strength.

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Ulrich Kleinekathoefer, Ivan Kondov, Michael Schreiber. 2000-12-06. Perturbative treatment of intercenter coupling in Redfield theory. https://doi.org/10.1016/s0301-0104(01)00288-9

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