Evidence for a hybridization gap in noncentrosymmetric CeRuSi3

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 $T_{\mathrm{K}}\sim 680$~K. The magnetic contribution to the specific heat ($C_{\mathrm{mag}}$) 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.

arXiv comment6 pages, 7 figures. Accepted for publication in Physical Review B

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Cited by in corpus (7)

• Superconductivity and spin-orbit coupling in non-centrosymmetric materials: a review
• Multiple quantum phase transitions and superconductivity in Ce-based heavy fermions
• Understanding the magnetism in noncentrosymmetric CeIrGe3: Muon spin relaxation and neutron scattering studies
• ARPES signature of the competition between magnetic order and Kondo effect in CeCoGe3
• Crystal field states of Kondo lattice heavy fermions CeRuSn3 and CeRhSn3
• Complex magnetic phases in polar tetragonal intermetallic NdCoGe${}_3$
• Pressure induced superconductivity in a CeRhSi${}_3$ single crystal -- the high pressure study