Elementary excitations in Kondo-systems CeNiSn and CeRhSb

Abstract

The anomalies in the low-temperature thermodynamics (heat capacity, thermal expansion) of Kondomaterials CENiSn and CeRhSb are explained in a framework of the theory of spin liquid in a Kondo lattice which was used previously for quantitative description of inelastic magnetic neutron scattering spectra (2.5meV and 4mcV excitations). These anomalies are explained by the interplay between the heavy fermions and the crystal field excitations in assumption that the crystal-field spliting δ _CF is less than Kondo temperatureT _K. It is shown that the V-shape pseudogap appears in a spin excitation branch but the charge excitations remain gapless. The spin excitation spectrum for an orthorhombic lattice turns out to be highly anisotropic.