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Atom Transfer and Single-Adatom Contacts

L. Limot·J. Kröger·R. Berndt·A. Garcia-Lekue·W. A. Hofer
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Abstract

The point contact of a tunnel tip approaching towards Ag(111) and Cu(111) surfaces is investigated with a low temperature scanning tunneling microscope. A sharp jump-to-contact, random in nature, is observed in the conductance. After point contact, the tip-apex atom is transferred to the surface, indicating that a one-atom contact is formed during the approach. In sharp contrast, the conductance over single silver and copper adatoms exhibits a smooth and reproducible transition from tunneling to contact regime. Numerical simulations show that this is a consequence of the additional dipolar bonding between the homoepitaxial adatom and the surface atoms.

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L. Limot, J. Kröger, R. Berndt, A. Garcia-Lekue, W. A. Hofer. 2004-12-09. Atom Transfer and Single-Adatom Contacts. https://doi.org/10.1103/physrevlett.94.126102

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