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Title: Decoherence and energy relaxation in the quantum-classical dynamics for charge transport in organic semiconducting crystals: An instantaneous decoherence correction approach

Abstract

We explore an instantaneous decoherence correction (IDC) approach for the decoherence and energy relaxation in the quantum-classical dynamics of charge transport in organic semiconducting crystals. These effects, originating from environmental fluctuations, are essential ingredients of the carrier dynamics. The IDC is carried out by measurement-like operations in the adiabatic representation. While decoherence is inherent in the IDC, energy relaxation is taken into account by considering the detailed balance through the introduction of energy-dependent reweighing factors, which could be either Boltzmann (IDC-BM) or Miller-Abrahams (IDC-MA) type. For a non-diagonal electron-phonon coupling model, it is shown that IDC tends to enhance diffusion while energy relaxation weakens this enhancement. As expected, both the IDC-BM and IDC-MA achieve a near-equilibrium distribution at finite temperatures in the diffusion process, while in the Ehrenfest dynamics the electronic system tends to infinite temperature limit. The resulting energy relaxation times with the two kinds of factors lie in different regimes and exhibit different dependences on temperature, decoherence time, and electron-phonon coupling strength, due to different dominant relaxation processes.

Authors:
 [1];  [1];  [2]
  1. State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22490886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHARGE TRANSPORT; CORRECTIONS; CRYSTALS; DIFFUSION; ELECTRON-PHONON COUPLING; ENERGY DEPENDENCE; FLUCTUATIONS; RELAXATION

Citation Formats

Si, Wei, Wu, Chang-Qin, E-mail: cqw@fudan.edu.cn, and Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433. Decoherence and energy relaxation in the quantum-classical dynamics for charge transport in organic semiconducting crystals: An instantaneous decoherence correction approach. United States: N. p., 2015. Web. doi:10.1063/1.4926534.
Si, Wei, Wu, Chang-Qin, E-mail: cqw@fudan.edu.cn, & Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433. Decoherence and energy relaxation in the quantum-classical dynamics for charge transport in organic semiconducting crystals: An instantaneous decoherence correction approach. United States. doi:10.1063/1.4926534.
Si, Wei, Wu, Chang-Qin, E-mail: cqw@fudan.edu.cn, and Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433. Tue . "Decoherence and energy relaxation in the quantum-classical dynamics for charge transport in organic semiconducting crystals: An instantaneous decoherence correction approach". United States. doi:10.1063/1.4926534.
@article{osti_22490886,
title = {Decoherence and energy relaxation in the quantum-classical dynamics for charge transport in organic semiconducting crystals: An instantaneous decoherence correction approach},
author = {Si, Wei and Wu, Chang-Qin, E-mail: cqw@fudan.edu.cn and Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433},
abstractNote = {We explore an instantaneous decoherence correction (IDC) approach for the decoherence and energy relaxation in the quantum-classical dynamics of charge transport in organic semiconducting crystals. These effects, originating from environmental fluctuations, are essential ingredients of the carrier dynamics. The IDC is carried out by measurement-like operations in the adiabatic representation. While decoherence is inherent in the IDC, energy relaxation is taken into account by considering the detailed balance through the introduction of energy-dependent reweighing factors, which could be either Boltzmann (IDC-BM) or Miller-Abrahams (IDC-MA) type. For a non-diagonal electron-phonon coupling model, it is shown that IDC tends to enhance diffusion while energy relaxation weakens this enhancement. As expected, both the IDC-BM and IDC-MA achieve a near-equilibrium distribution at finite temperatures in the diffusion process, while in the Ehrenfest dynamics the electronic system tends to infinite temperature limit. The resulting energy relaxation times with the two kinds of factors lie in different regimes and exhibit different dependences on temperature, decoherence time, and electron-phonon coupling strength, due to different dominant relaxation processes.},
doi = {10.1063/1.4926534},
journal = {Journal of Chemical Physics},
number = 2,
volume = 143,
place = {United States},
year = {Tue Jul 14 00:00:00 EDT 2015},
month = {Tue Jul 14 00:00:00 EDT 2015}
}
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