Spin excitation of Co atoms at monatomic Cu chains

Neda Noei; Roberto Mozara; Ana M. Montero; Sascha Brinker; Niklas Ide; Filipe S. M. Guimarães; Alexander I. Lichtenstein; Richard Berndt; Samir Lounis; Alexander Weismann

arXiv · 2303.03317

Spin excitation of Co atoms at monatomic Cu chains

Neda Noei·Roberto Mozara·Ana M. Montero·Sascha Brinker·Niklas Ide·Filipe S. M. Guimarães·Alexander I. Lichtenstein·Richard Berndt·Samir Lounis·Alexander Weismann

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Abstract

The zero-bias anomaly in conductance spectra of single Co atoms on Cu(111) observed at $\approx$ 4 K, which has been interpreted as being due to a Kondo resonance, is strongly modified when the Co atoms are attached to monatomic Cu chains. Scanning tunneling spectra measured at 340 mK in magnetic fields exhibit all characteristics of spin-flip excitations. Their dependence on the magnetic field reveals a magnetic anisotropy and suggests a non-collinear spin state. This indicates that spin-orbit coupling (SOC), which has so far been neglected in theoretical studies of Co/Cu(111), has to be taken into account. According to our density functional theory and multi-orbital quantum Monte Carlo calculations SOC suppresses the Kondo effect for all studied geometries.

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Neda Noei, Roberto Mozara, Ana M. Montero, Sascha Brinker, Niklas Ide, Filipe S. M. Guimarães, Alexander I. Lichtenstein, Richard Berndt, Samir Lounis, Alexander Weismann. 2023-03-06. Spin excitation of Co atoms at monatomic Cu chains. https://arxiv.org/abs/2303.03317

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