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arXiv · 0906.4518

Environment effects on the electric conductivity of the DNA

A. V. Malyshev·E. Diaz·F. Dominguez-Adame·V. A. Malyshev
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Abstract

We present a theoretical analysis of the environment effects 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 the static disorder and (ii) phonon-induced scattering of the carrier between these 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. Simple physical explanation of this effect is provided.

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A. V. Malyshev, E. Diaz, F. Dominguez-Adame, V. A. Malyshev. 2009-06-24. Environment effects on the electric conductivity of the DNA. https://doi.org/10.1088/0953-8984%2F21%2F33%2F335105

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