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Exchange interaction between single magnetic adatoms

P. Wahl·P. Simon·L. Diekhoener·V. S. Stepanyuk·P. Bruno·M. A. Schneider·K. Kern
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Abstract

The magnetic coupling between single Co atoms adsorbed on a copper surface is determined by probing the Kondo resonance using low-temperature scanning tunneling spectroscopy. The Kondo resonance, which is due to magnetic correlation effects between the spin of a magnetic adatom and the conduction electrons of the substrate, is modified in a characteristic way by the coupling of the neighbouring adatom spins. Increasing the interatomic distance of a Cobalt dimer from 2.56A to 8.1A we follow the oscillatory transition from ferromagnetic to antiferromagnetic coupling. Adding a third atom to the antiferromagnetically coupled dimer results in the formation of a collective correlated state.

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P. Wahl, P. Simon, L. Diekhoener, V. S. Stepanyuk, P. Bruno, M. A. Schneider, K. Kern. 2007-02-11. Exchange interaction between single magnetic adatoms. https://doi.org/10.1103/physrevlett.98.056601

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