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Register a new userDouble path-integral method for obtaining the mobility of the one-dimensional charge transport in molecular chain
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We report on a theoretical investigation concerning the polaronic effect on the transport properties of a charge carrier in the one-dimensional molecular chain. Our technique is based on the Feynmans path integral approach. Analytical expressions for the frequency-dependent mobility and effective mass of the carrier are obtained as functions of electron-phonon coupling. The result exhibits the crossover from a nearly free particle to a heavily trapped particle. We find that the mobility depends on temperature and decreases exponentially with increasing temperature at low temperature. It exhibits large-polaronic-like behaviour in the case of weak electron-phonon coupling. These results agree with the phase transition cite{Mish} of transport phenomena related to polaron motion in the molecular chain.
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