title: Effects of the environment on the electric conductivity of double-stranded DNA molecules.
abstract: We present a theoretical analysis of the effects of the environment on charge transport in double-stranded synthetic poly(G)-poly(C) DNA molecules attached to two ideal leads. Coupling of the DNA to the environment results in two effects: (i) localization of carrier functions due to static disorder and (ii) phonon-induced scattering of the carriers between the localized states, resulting in hopping conductivity. A nonlinear Pauli master equation for populations of localized states is used to describe the hopping transport and calculate the electric current as a function of the applied bias. We demonstrate that, although the electronic gap in the density of states shrinks as the disorder increases, the voltage gap in the I-V characteristics becomes wider. A simple physical explanation of this effect is provided.
authors.affiliation: GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid, Spain.
authors.forename: A V
authors.initials: AV
authors.lastname: Malyshev
authors.forename: E
authors.initials: E
authors.lastname: Díaz
authors.forename: F
authors.initials: F
authors.lastname: Domínguez-Adame
authors.forename: V A
authors.initials: VA
authors.lastname: Malyshev