Accurate nonadiabatic quantum dynamics on the cheap: making the most of mean field theory with master equations.

Abstract

In this article, we show how Ehrenfest mean field theory can be made both a more accurate and efficient method to treat nonadiabatic quantum dynamics by combining it with the generalized quantum master equation framework. The resulting mean field generalized quantum master equation (MF-GQME) approach is a non-perturbative and non-Markovian theory to treat open quantum systems without any restrictions on the form of the Hamiltonian that it can be applied to. By studying relaxation dynamics in a wide range of dynamical regimes, typical of charge and energy transfer, we show that MF-GQME provides a much higher accuracy than a direct application of mean field theory. In addition, these increases in accuracy are accompanied by computational speed-ups of between one and two orders of magnitude that become larger as the system becomes more nonadiabatic. This combination of quantum-classical theory and master equation techniques thus makes it possible to obtain the accuracy of much more computationally expensive approaches at a cost lower than even mean field dynamics, providing the ability to treat the quantum dynamics of atomistic condensed phase systems for long times.

DOI: 10.1063/1.4913686

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Cite this paper

@article{Kelly2015AccurateNQ, title={Accurate nonadiabatic quantum dynamics on the cheap: making the most of mean field theory with master equations.}, author={Aaron Kelly and Nora Brackbill and Thomas E Markland}, journal={The Journal of chemical physics}, year={2015}, volume={142 9}, pages={094110} }