Charge transport in l-DNA probed by conducting-AFM, and relationship with its structure

Thomas Heim; Dominique Deresemes; Dominique Vuillaume

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arXiv · cond-mat/0310242

Charge transport in l-DNA probed by conducting-AFM, and relationship with its structure

Thomas Heim·Dominique Deresemes·Dominique Vuillaume

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Abstract

We studied the electrical conductivity of DNA samples as function of the number of DNA molecules. We showed that the insulating gap (no current at low voltage) increases from ~1-2 V for bundles and large ropes to ~4-7 V for few DNA molecules. From the distance dependent variation of the current, a unique hopping distance of ~3 nm is calculated (polaron-hopping model) independently of the number of DNA in the sample. The highly resistive behavior of the single DNA is correlated with its flattened conformation on the surface (reduced thickness, ~0.5-1.5 nm, compared to its nominal value, ~2 nm).

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Thomas Heim, Dominique Deresemes, Dominique Vuillaume. 2003-10-10. Charge transport in l-DNA probed by conducting-AFM, and relationship with its structure. https://arxiv.org/abs/cond-mat/0310242

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