Weyl-Kondo semimetal behavior in the chiral structure phase of Ce3Rh4Sn13

Abstract

The spin dynamics, crystalline-electric-field (CEF) level scheme, specific heat, and x-ray photoemission spectra (XPS) of Ce3Rh4Sn13 were investigated, which exhibits anomalous semimetal transport in the chiral crystallographic phase. CEF excitations observed at approximately 7 and 39 meV are consistent with the two inequivalent Ce-ion cites in the chiral structure. Because of broader CEF excitations and a strong 4f1 peak at the Fermi level in the Ce 4f on-resonance spectrum, the hybridized Ce 4f electrons contribute to the semimetal carriers. In addition, the spin fluctuation associated with the Kramers doublet ground state is characterized by the peak located at 0.15 meV. The electronic state involving the spin fluctuation causes the T3 behavior of specific heat below 0.6 K, which is attributed to linear dispersion relations of electrons of the Weyl-Kondo semimetal in the chiral-lattice symmetry.