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arXiv · 1905.00716

Bulk properties of single crystals of the valence-unstable compound SmRh$_2$Si$_2$

Kristin Kliemt·Jacintha Banda·Christoph Geibel·Manuel Brando·Cornelius Krellner
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Abstract

We present the crystal growth as well as the structural, chemical and physical chracterization of SmRh$_2$Si$_2$ single crystals. Their ground state is antiferromagnetic, as indicated by the behaviour of the magnetic susceptibility and the specific heat at the second order phase transition observed at T$_{\rm N}$ = 64 K. The Sommerfeld coefficient is small and similar to that of LuRh$_2$Si$_2$ with $\gamma_0\approx$ J/(molK$^2$). Susceptibility measurements show no Curie-Weiss behaviour at high temperatures which is a consequence of the large Van-Vleck contribution of the excited multiplets of Sm$^{3+}$. Previous angle-resolved photoemission studies showed that at 10 K, the valence of the Sm ions is smaller than three at the surface as well as in the bulk, suggesting a possible Kondo screening of the Sm$^{3+}$ ions. This could not be observed in our thermodynamic and transport measurements.

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Kristin Kliemt, Jacintha Banda, Christoph Geibel, Manuel Brando, Cornelius Krellner. 2019-05-02. Bulk properties of single crystals of the valence-unstable compound SmRh$_2$Si$_2$. https://arxiv.org/abs/1905.00716

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