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arXiv · 2312.03364

Tuning spinaron and Kondo resonances via quantum confinement

Markus Aapro·Abraham Kipnis·Jose L. Lado·Shawulienu Kezilebieke·Peter Liljeroth
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Abstract

Controlling zero bias anomalies in magnetic atoms provides a promising strategy to engineer tunable quantum many-body excitations. Here we show how two different quantum impurities featuring spinaron and Kondo excitations can be controlled via quantum confinement engineering by using circular quantum corrals on a Ag(111) surface. In corrals built from both Ag and Co adatoms, the width of the zero bias anomaly in the central Co adatom oscillates as a function of corral radius with a period of half of the Ag(111) surface state wavelength. Parameters extracted for Co/Ag(111) show only small differences in extracted spinaron zero-bias anomaly between corral walls built from Ag or Co adatoms. In quantum corrals occupied with metal-free phthalocyanine, a $S=1/2$ Kondo system, we observe notable changes in the zero bias anomaly lineshape as a function of corral radius. Our results offer insight into many-body Kondo and spinaron resonances where the electronic density is controlled by confinement engineering.

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Markus Aapro, Abraham Kipnis, Jose L. Lado, Shawulienu Kezilebieke, Peter Liljeroth. 2023-12-06. Tuning spinaron and Kondo resonances via quantum confinement. https://doi.org/10.1103/physrevb.109.195415

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