Bramley, O, Symonds, C orcid.org/0000-0001-7952-3805 and Shalashilin, DV orcid.org/0000-0001-6104-1277 (2019) Quantum system-bath dynamics with quantum superposition sampling and coupled generalized coherent states. Journal of Chemical Physics, 151. 064103. ISSN 0021-9606
Abstract
Previously, we introduced two versions of the Multiconfigurational Ehrenfest (MCE) approach to high dimensional quantum dynamics. It has been shown that the first version, MCEv1, converges well to the existing benchmarks for high dimensional model systems. At the same time, it was found that the second version, MCEv2, had more difficulty converging in some regimes. As MCEv2 is particularly suited for direct dynamics, it is important to facilitate its convergence. This paper investigates an efficient method of basis set sampling, called Quantum Superposition Sampling (QSS), which dramatically improves the performance of the MCEv2 approach. QSS is tested on the spin-boson model, often used for modeling of open quantum systems. It is also shown that the quantum subsystem in the spin-boson model can be conveniently treated with the help of two level system coherent states. Generalized coherent states, which combine two level system coherent states for the description of the system and Gaussian coherent states for description of the bath, are introduced. Various forms of quantum equations of motion in the basis of generalized coherent states can be developed by analogy with known quantum dynamics equations in the basis of Gaussian coherent states; in particular, the multiconfigurational Ehrenfest method becomes a version of coupled generalized coherent states, and QSS can then be viewed as a generalization of a sampling method known for the existing coupled coherent states method which uses Gaussian coherent states.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2019 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst for Climate & Atmos Science (ICAS) (Leeds) The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemistry (Leeds) > Physical Chemistry (Leeds) |
Funding Information: | Funder Grant number Leverhulme Trust RPG-2015-190 EPSRC EP/P021123/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 17 Jul 2019 13:28 |
Last Modified: | 10 Nov 2021 16:03 |
Status: | Published |
Publisher: | American Institute of Physics |
Identification Number: | 10.1063/1.5100145 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:148650 |
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Filename: MCE_QSS_Supporting_Information_revised_final.pdf
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