Journal article
Conduction channels at finite bias in single-atom gold contacts
Theoretical Nanoelectronics Group, Theory Section, Department of Micro- and Nanotechnology, Technical University of Denmark1
Theory Section, Department of Micro- and Nanotechnology, Technical University of Denmark2
Department of Micro- and Nanotechnology, Technical University of Denmark3
RIKEN4
The University of Tokyo5
We consider the effect of a finite voltage bias on the conductance of single-atom gold contacts. We employ a nonorthogonal spn-tight-binding Hamiltonian combined with a local charge neutrality assumption. The conductance and charge distributions for finite bias are calculated using the nonequilibrium-Green-function formalism.
We calculate the voltage drop through the contacts and find the main drop located near the negative electrode. We argue that this is due to the filled d-state resonances. The conduction is analyzed in terms of transmission eigenchannels and density of states of the eigenchannels projected onto tight-binding orbitals.
We find a single almost fully transmitting channel with mainly s character for low bias while for high bias this channel becomes less transmitting and additional channels involving only d orbitals start to conduct.
Language: | English |
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Year: | 1999 |
Pages: | 17064-17070 |
ISSN: | 10953795 , 01631829 and 1550235x |
Types: | Journal article |
DOI: | 10.1103/PhysRevB.60.17064 |
ORCIDs: | Brandbyge, Mads |