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Title: 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.

Authors:
;  [1];  [2]
  1. Department of Chemistry, Stanford University, Stanford, California 94305 (United States)
  2. Department of Physics, Stanford University, Stanford, California 94305 (United States)
Publication Date:
OSTI Identifier:
22416206
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCURACY; ENERGY TRANSFER; EQUATIONS; HAMILTONIANS; MARKOV PROCESS; MEAN-FIELD THEORY; QUANTUM SYSTEMS; RELAXATION; VELOCITY

Citation Formats

Kelly, Aaron, Markland, Thomas E., E-mail: tmarkland@stanford.edu, and Brackbill, Nora. Accurate nonadiabatic quantum dynamics on the cheap: Making the most of mean field theory with master equations. United States: N. p., 2015. Web. doi:10.1063/1.4913686.
Kelly, Aaron, Markland, Thomas E., E-mail: tmarkland@stanford.edu, & Brackbill, Nora. Accurate nonadiabatic quantum dynamics on the cheap: Making the most of mean field theory with master equations. United States. doi:10.1063/1.4913686.
Kelly, Aaron, Markland, Thomas E., E-mail: tmarkland@stanford.edu, and Brackbill, Nora. Sat . "Accurate nonadiabatic quantum dynamics on the cheap: Making the most of mean field theory with master equations". United States. doi:10.1063/1.4913686.
@article{osti_22416206,
title = {Accurate nonadiabatic quantum dynamics on the cheap: Making the most of mean field theory with master equations},
author = {Kelly, Aaron and Markland, Thomas E., E-mail: tmarkland@stanford.edu and Brackbill, Nora},
abstractNote = {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},
journal = {Journal of Chemical Physics},
number = 9,
volume = 142,
place = {United States},
year = {Sat Mar 07 00:00:00 EST 2015},
month = {Sat Mar 07 00:00:00 EST 2015}
}