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Conductance and Kondo effect of a controlled single atom contact

N. Neel·J. Kroeger·L. Limot·K. Palotas·W. A. Hofer·R. Berndt
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Abstract

The tip of a low-temperature scanning tunneling microscope is brought into contact with individual Kondo impurities (cobalt atoms) adsorbed on a Cu(100) surface. A smooth transition from the tunneling regime to a point contact with a conductance of $G\approx\text{G}_0$ occurs. Spectroscopy in the contact regime, {\it i. e.}, at currents in a $μ\text{A}$ range was achieved. A modified line shape is observed indicating a significant change of the Kondo temperature $T_{\text{K}}$ at contact. Model calculations indicate that the proximity of the tip shifts the cobalt $d$-band and thus affects $T_{\text{K}}$.

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N. Neel, J. Kroeger, L. Limot, K. Palotas, W. A. Hofer, R. Berndt. 2006-10-16. Conductance and Kondo effect of a controlled single atom contact. https://arxiv.org/abs/cond-mat/0610419

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