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Temperature dependence of the Kondo resonance and its satellites in CeCu_2Si_2

F. Reinert·D. Ehm·S. Schmidt·G. Nicolay·S. H"ufner·J. Kroha·O. Trovarelli·C. Geibel
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Abstract

We present high-resolution photoemission spectroscopy studies on the Kondo resonance of the strongly-correlated Ce system CeCu$_2$Si$_2$. Exploiting the thermal broadening of the Fermi edge we analyze position, spectral weight, and temperature dependence of the low-energy 4f spectral features, whose major weight lies above the Fermi level $E_F$. We also present theoretical predictions based on the single-impurity Anderson model using an extended non-crossing approximation (NCA), including all spin-orbit and crystal field splittings of the 4f states. The excellent agreement between theory and experiment provides strong evidence that the spectral properties of CeCu$_2$Si$_2$ can be described by single-impurity Kondo physics down to $T \approx 5$ K.

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F. Reinert, D. Ehm, S. Schmidt, G. Nicolay, S. H"ufner, J. Kroha, O. Trovarelli, C. Geibel. 2001-04-02. Temperature dependence of the Kondo resonance and its satellites in CeCu_2Si_2. https://doi.org/10.1103/physrevlett.87.106401

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