Quantum transport through a DNA wire in a dissipative environment

R. Gutierrez; S. Mandal; G. Cuniberti

doi:10.1021/nl050623g

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Quantum transport through a DNA wire in a dissipative environment

R. Gutierrez·S. Mandal·G. Cuniberti

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Abstract

Electronic transport through DNA wires in the presence of a strong dissipative environment is investigated. We show that new bath-induced electronic states are formed within the bandgap. These states show up in the linear conductance spectrum as a temperature dependent background and lead to a crossover from tunneling to thermal activated behavior with increasing temperature. Depending on the strength of the electron-bath coupling, the conductance at the Fermi level can show a weak exponential or even an algebraic length dependence. Our results suggest a new environmental-induced transport mechanism. This might be relevant for the understanding of molecular conduction experiments in liquid solution, like those recently performed on poly(GC) oligomers in a water buffer (B. Xu et al., Nano Lett 4, 1105 (2004)).

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R. Gutierrez, S. Mandal, G. Cuniberti. 2005-05-24. Quantum transport through a DNA wire in a dissipative environment. https://doi.org/10.1021/nl050623g

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