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arXiv · 1104.0608

On the Munn-Silbey approach to polaron transport with off-diagonal coupling

Dongmeng Chen·Jun Ye·Haijun Zhang·Yang Zhao
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Abstract

Improved results using a method similar to the Munn-Silbey approach have been obtained on the temperature dependence of transport properties of an extended Holstein model incorporating simultaneous diagonal and off-diagonal exciton-phonon coupling. The Hamiltonian is partially diagonalized by a canonical transformation, and optimal transformation coefficients are determined in a self-consistent manner. Calculated transport properties exhibit substantial corrections on those obtained previously by Munn and Silbey for a wide range of temperatures thanks to a numerically exact evaluation and an added momentum-dependence of the transformation matrix. Results on the diffusion coefficient in the moderate and weak coupling regime show distinct band-like and hopping-like transport features as a function of temperature.

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Dongmeng Chen, Jun Ye, Haijun Zhang, Yang Zhao. 2011-04-06. On the Munn-Silbey approach to polaron transport with off-diagonal coupling. https://doi.org/10.1021/jp1093492

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