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arXiv · 2003.01746

A new view on the origin of zero-bias anomalies of Co atoms atop noble metal surfaces

Juba Bouaziz·Filipe Souza Mendes Guimarães·Samir Lounis
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Abstract

Many-body phenomena are paramount in physics. In condensed matter, their hallmark is considerable on a wide range of material characteristics spanning electronic, magnetic, thermodynamic and transport properties. They potentially imprint non-trivial signatures in spectroscopic measurements, such as those assigned to Kondo, excitonic and polaronic features, whose emergence depends on the involved degrees of freedom. Here, we address systematically zero-bias anomalies detected by scanning tunneling spectroscopy on Co atoms deposited on Cu, Ag and Au(111) substrates, which remarkably are almost identical to those obtained from first-principles. These features originate from gaped spin-excitations induced by a finite magnetic anisotropy energy, in contrast to the usual widespread interpretation relating them to Kondo resonances. Resting on relativistic time-dependent density functional and many-body perturbation theories, we furthermore unveil a new many-body feature, the spinaron, resulting from the interaction of electrons and spin-excitations localizing electronic states in a well defined energy.

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Juba Bouaziz, Filipe Souza Mendes Guimarães, Samir Lounis. 2020-03-03. A new view on the origin of zero-bias anomalies of Co atoms atop noble metal surfaces. https://doi.org/10.1038/s41467-020-19746-1

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