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arXiv · 0705.0527

Tuning the conductance of a molecular switch

Miriam del Valle·Rafael Gutierrez·Carlos Tejedor·Gianaurelio Cuniberti
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Abstract

The ability to control the conductance of single molecules will have a major impact in nanoscale electronics. Azobenzene, a molecule that changes conformation as a result of a trans/cis transition when exposed to radiation, could form the basis of a light-driven molecular switch. It is therefore crucial to clarify the electrical transport characteristics of this molecule. Here, we investigate theoretically charge transport in a system in which a single azobenzene molecule is attached to two carbon nanotubes. In clear contrast to gold electrodes, the nanotubes can act as true nanoscale electrodes and we show that the low-energy conduction properties of the junction may be dramatically modified by changing the topology of the contacts between the nanotubes and the molecules, and/or the chirality of the nanotubes (that is, zigzag or armchair). We propose experiments to demonstrate controlled electrical switching with nanotube electrodes.

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Miriam del Valle, Rafael Gutierrez, Carlos Tejedor, Gianaurelio Cuniberti. 2007-05-03. Tuning the conductance of a molecular switch. https://doi.org/10.1038/nnano.2007.38

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