Berlin 2008 – wissenschaftliches Programm
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TT: Fachverband Tiefe Temperaturen
TT 35: Transport: Nanoelectronics I - Quantum Dots, Wires, Point Contacts 3
TT 35.3: Vortrag
Donnerstag, 28. Februar 2008, 14:30–14:45, H 3010
Electrical conductance through nanocontacts between fcc(100) electrodes of gold — •Daniela Koudela1, Olga Lopez-Acevedo1, Michael Walter1, and Hannu Häkkinen1,2 — 1Department of Physics, Nanoscience Center, P.O. Box 35, FIN-40014 University of Jyväskylä — 2Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä
Both experimental and theoretical work has been done to explain conductance curves for metal nanowires, giving presently a good model that allows to explain experimental results microscopically. For one atom contacts it has moreover been shown, theoretically and experimentally, a strong relation between the number of valence orbitals of the single atom and the maximum value of the conductance that can be obtained [1].
We have studied Au nanowires of different lengths connected to fcc(100) tips corresponding to possible configurations in the elongation process. For those systems we have calculated the self-consistent potential obtained with Density Functional Theory and used it to calculate the conductance using the recursion-transfer-matrix method [2]. Our results show that though gold has formally only one valence electron (6s), for wires shorter than 3 atoms there are 3 (partially) open eigenmodes. [3]
[1] E. Scheer et al., Nature 394, 154 (1998)
[2] M. Brandbyge, K. W. Jacobsen, J. K. Norskov, Phys. Rev. B 55, 2637 (1997)
[3] O. Lopez-Acevedo et al., in preparation.