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Inelastic quantum transport in a ladder model: Measurements of DNA conduction and comparison to theory

R. Gutierrez·S. Mohapatra·H. Cohen·D. Porath·G. Cuniberti
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Abstract

We investigate quantum transport characteristics of a ladder model, which effectively mimics the topology of a double-stranded DNA molecule. We consider the interaction of tunneling charges with a selected internal vibrational degree of freedom and discuss its influence on the structure of the current-voltage characteristics. Further, molecule-electrode contact effects are shown to dramatically affect the orders of magnitude of the current. Recent electrical transport measurements on suspended DNA oligomers with a complex base-pair sequence, revealing strikingly high currents, are also presented and used as a reference point for the theoretical modeling. A semi-quantitative description of the measured I-V curves is achieved, suggesting that the coupling to vibrational excitations plays an important role in DNA conduction.

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R. Gutierrez, S. Mohapatra, H. Cohen, D. Porath, G. Cuniberti. 2006-07-14. Inelastic quantum transport in a ladder model: Measurements of DNA conduction and comparison to theory. https://arxiv.org/abs/cond-mat/0604435

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