Trajectory Ensemble Methods Provide Single-Molecule Statistics for Quantum Dynamical Systems.

Autor: Dodin A; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States., Provazza J; Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.; Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States., Coker DF; Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States., Willard AP; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Jazyk: angličtina
Zdroj: Journal of chemical theory and computation [J Chem Theory Comput] 2022 Apr 12; Vol. 18 (4), pp. 2047-2061. Date of Electronic Publication: 2022 Mar 01.
DOI: 10.1021/acs.jctc.1c00477
Abstrakt: The emergence of experiments capable of probing quantum dynamics at the single-molecule level requires the development of new theoretical tools capable of simulating and analyzing these dynamics beyond an ensemble-averaged description. In this article, we present an efficient method for sampling and simulating the dynamics of the individual quantum systems that make up an ensemble and apply it to study the nonequilibrium dynamics of the ubiquitous spin-boson model. We generate an ensemble of single-system trajectories, and we analyze this trajectory ensemble using tools from classical statistical mechanics. Our results demonstrate that the dynamics of quantum coherence is highly heterogeneous at the single-system level due to variations in the initial bath configuration, which significantly affects the transient exchange of coherence between the system and its bath. We observe that single systems tend to retain coherence over time scales longer than that of the ensemble. We also compute a novel thermodynamic entanglement entropy that quantifies a thermodynamic driving force favoring system-bath entanglement.
Databáze: MEDLINE