title: Charge transport in DNA: dependence of diffusion coefficient on temperature and electron-phonon coupling constant.
abstract: The diffusion coefficient is calculated for a charge propagating along a double-stranded DNA, while it interacts with the nonlinear fluctuational openings of base pairs. The latter structural dynamics of DNA is described by the Peyrard-Bishop-Dauxois model [T. Dauxois, M. Peyrard, and A. R. Bishop, Phys Rev. E 47 R44 (1993)], which represents essential anharmonicities of base-pair stretchings. The dependence of the diffusion coefficient on the temperature and the electron-phonon coupling constant is presented. The diffusion coefficient decreases when either the temperature or the electron-phonon coupling increases. Analytical expressions are provided that describe the temperature dependence of the diffusion coefficient. The variation of the parameters of these expressions with the electron-phonon coupling constant is also discussed. These results quantitatively demonstrate how DNA structural nonlinear dynamics affects macroscopic charge transport properties.
authors.affiliation: University of Patras, GR-26504 Rio, Greece.
authors.forename: G
authors.initials: G
authors.lastname: Kalosakas
mesh_terms: D004247:DNA / Q000737:chemistry*; D004058:Diffusion; D004579:Electron Transport; D004583:Electrons; D060739:Phonons; D013696:Temperature
chemical_list: D004247:DNA