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arXiv · 1204.0152

Disorder and dephasing effect on electron transport through conjugated molecular wires in molecular junctions

Daijiro Nozaki·Claudia Gomes da Rocha·Horacio M. Pastawski·Gianaurelio Cuniberti
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Abstract

Understanding electron transport processes in molecular wires connected between contacts is a central focus in the field of molecular electronics. Especially, the dephasing effect causing tunneling-to-hopping transition has great importance from both applicational and fundamental points of view. We analyzed coherent and incoherent electron transmission through conjugated molecular wires by means of density-functional tight-binding theory within the D'Amato-Pastawski model. Our approach can study explicitly the structure/transport relationship in molecular junctions in a dephasing environmental condition using only single dephasing parameter. We investigated the length dependence and the influence of thermal fluctuations on transport and reproduced the well-known tunneling-to-hopping transition. This approach will be a powerful tool for the interpretation of recent conductance measurements of molecular wires.

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Daijiro Nozaki, Claudia Gomes da Rocha, Horacio M. Pastawski, Gianaurelio Cuniberti. 2012-04-01. Disorder and dephasing effect on electron transport through conjugated molecular wires in molecular junctions. https://doi.org/10.1103/physrevb.85.155327

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