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arXiv · 1604.03854

Tuning emergent magnetism in a Hund's impurity

A. A. Khajetoorians·M. Valentyuk·M. Steinbrecher·T. Schlenk·A. Shick·J. Kolorenc·A. I. Lichtenstein·T. O. Wehling·R. Wiesendanger·J. Wiebe
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Abstract

The recently proposed theoretical concept of a Hund's metal is regarded as a key to explain the exotic magnetic and electronic behavior occuring in the strongly correlated electron systems of multiorbital metallic materials. However, a tuning of the abundance of parameters, that determine these systems, is experimentally challenging. Here, we investigate the smallest possible realization of a Hund's metal, a Hund's impurity, realized by a single magnetic impurity strongly hybridized to a metallic substrate. We experimentally control all relevant parameters including magnetic anisotropy and hybridization by hydrogenation with the tip of a scanning tunneling microscope and thereby tune it through a regime from emergent magnetic moments into a multi-orbital Kondo state. Our comparison of the measured temperature and magnetic field dependent spectral functions to advanced many-body theories will give relevant input for their application to non-Fermi liquid transport, complex magnetic order, or unconventional superconductivity.

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A. A. Khajetoorians, M. Valentyuk, M. Steinbrecher, T. Schlenk, A. Shick, J. Kolorenc, A. I. Lichtenstein, T. O. Wehling, R. Wiesendanger, J. Wiebe. 2016-04-13. Tuning emergent magnetism in a Hund's impurity. https://doi.org/10.1038/nnano.2015.193

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