A variational approach for dissipative quantum transport in a wide parameter space

Journal Article · Mon Sep 14 04:00:00 EDT 2015 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4930847· OSTI ID:22489561

Zhang, Yu; Kwok, YanHo; Chen, GuanHua ^[1]; Yam, ChiYung ^[1]

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1. Department of Chemistry, The University of Hong Kong, Pokfluam Road (Hong Kong)

Recent development of theoretical method for dissipative quantum transport has achieved notable progresses in the weak or strong electron-phonon coupling regime. However, a generalized theory for dissipative quantum transport in a wide parameter space had not been established. In this work, a variational polaron theory for dissipative quantum transport in a wide range of electron-phonon coupling is developed. The optimal polaron transformation is determined by the optimization of the Feynman-Bogoliubov upper bound of free energy. The free energy minimization ends up with an optimal mean-field Hamiltonian and a minimal interaction Hamiltonian. Hence, second-order perturbation can be applied to the transformed system, resulting in an accurate and efficient method for the treatment of dissipative quantum transport with different electron-phonon coupling strength. Numerical benchmark calculation on a single site model coupled to one phonon mode is presented.

• OSTI ID: 22489561
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 10 Vol. 143; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTRON-PHONON COUPLING
FREE ENERGY
HAMILTONIANS
INTERACTIONS
MEAN-FIELD THEORY
MINIMIZATION
PERTURBATION THEORY
PHONONS
VARIATIONAL METHODS