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arXiv · 1502.01231

Evidence for a hybridization gap in noncentrosymmetric CeRuSi3

M. Smidman·D. T. Adroja·E. A. Goremychkin·M. R. Lees·D. M. Paul·G. Balakrishnan
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Abstract

Inelastic neutron scattering (INS) and specific heat measurements have been performed on the intermediate valence compound CeRuSi$_3$, which is isostructural to the noncentrosymmetric pressure-induced superconductors CeRhSi$_3$, CeIrSi$_3$ and CeCoGe$_3$. INS measurements at 7~K reveal a broad peak at (58.5~$\pm$~1.4)~meV, while at 300~K, broad quasielastic scattering is observed. This indicates a large Kondo temperature of $T_{\rm K}~\sim~680$~K. The magnetic contribution to the specific heat ($C_{\rm mag}$) has a value of $\gamma~=~62.5(1)$~mJ/mol~K$^2$ at low temperatures and above about 100~K can be well accounted for by the Coqlbin-Schrieffer model with a characteristic temperature of $T_0$~=~680~K, which is further evidence that CeRuSi$_3$ is in the intermediate valence regime.

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M. Smidman, D. T. Adroja, E. A. Goremychkin, M. R. Lees, D. M. Paul, G. Balakrishnan. 2015-02-04. Evidence for a hybridization gap in noncentrosymmetric CeRuSi3. https://doi.org/10.1103/physrevb.91.064419

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