Eur. Phys. J. E (2015) 38: 135
https://doi.org/10.1140/epje/i2015-15135-y

Regular Article

Double path integral method for obtaining the mobility of the one-dimensional charge transport in molecular chain

¹ Theoretical and Computational Physics (TCP) Group, Department of Physics, Faculty of Science, King Mongkut’s University of Technology Thonburi, 10140, Bangkok, Thailand
² Theoretical and Computational Science Centre (TaCS), Faculty of Science, King Mongkut’s University of Technology Thonburi, 10140, Bangkok, Thailand
³ Ratchaburi Campus, King Mongkut’s University of Technology Thonburi, 70510, Ratchaburi, Thailand
⁴ ThEP Center, Commission of Higher Education, 328 Si Ayuthaya Rd., 10400, Bangkok, Thailand

^* e-mail: sikarin.yoo@kmutt.ac.th
^** e-mail: watchara.lie@kmutt.ac.th

Received: 11 October 2014
Accepted: 17 November 2015
Published online: 28 December 2015

Abstract

We report on a theoretical investigation concerning the polaronic effect on the transport properties of a charge carrier in a one-dimensional molecular chain. Our technique is based on the Feynman’s 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 (A.S. Mishchenko et al., Phys. Rev. Lett. 114, 146401 (2015)) of transport phenomena related to polaron motion in the molecular chain.