| Autor: |
Quek, Su Ying, Kamenetska, Maria, Steigerwald, Michael L., Choi, Hyoung Joon, Louie, Steven G., Hybertsen, Mark S., Neaton, J. B., Venkataraman, L. |
| Rok vydání: |
2009 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| DOI: |
10.1038/nnano.2009.10 |
| Popis: |
Molecular-scale components are expected to be central to nanoscale electronic devices. While molecular-scale switching has been reported in atomic quantum point contacts, single-molecule junctions provide the additional flexibility of tuning the on/off conductance states through molecular design. Thus far, switching in single-molecule junctions has been attributed to changes in the conformation or charge state of the molecule. Here, we demonstrate reversible binary switching in a single-molecule junction by mechanical control of the metal-molecule contact geometry. We show that 4,4'-bipyridine-gold single-molecule junctions can be reversibly switched between two conductance states through repeated junction elongation and compression. Using first-principles calculations, we attribute the different measured conductance states to distinct contact geometries at the flexible but stable N-Au bond: conductance is low when the N-Au bond is perpendicular to the conducting pi-system, and high otherwise. This switching mechanism, inherent to the pyridine-gold link, could form the basis of a new class of mechanically-activated single-molecule switches. |
| Databáze: |
arXiv |
| Externí odkaz: |
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