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Backbone-induced semiconducting behavior in short DNA wires

G. Cuniberti·L. Craco·D. Porath·C. Dekker
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Abstract

We propose a model Hamiltonian for describing charge transport through short homogeneous double stranded DNA molecules. We show that the hybridization of the overlapping pi orbitals in the base-pair stack coupled to the backbone is sufficient to predict the existence of a gap in the nonequilibrium current-voltage characteristics with a minimal number of parameters. Our results are in a good agreement with the recent finding of semiconducting behavior in short poly(G)-poly(C) DNA oligomers. In particular, our model provides a correct description of the molecular resonances which determine the quasi-linear part of the current out of the gap region.

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G. Cuniberti, L. Craco, D. Porath, C. Dekker. 2002-05-17. Backbone-induced semiconducting behavior in short DNA wires. https://doi.org/10.1103/physrevb.65.241314

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