On the Munn−Silbey approach to polaron transport with off-diagonal coupling and temperature-dependent canonical transformations

• Main Authors: Chen, Dongmeng, Ye, Jun, Zhang, Haijun, Zhao, Yang
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2012
• Subjects: DRNTU::Science::Physics::Atomic physics::Solid state physics
• Online Access: https://hdl.handle.net/10356/94605; http://hdl.handle.net/10220/7449
• Institution: Nanyang Technological University

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.