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Interplay between Heavy Fermions and Crystal Field Excitation in Kondo Lattices. Low-Temperature Thermodynamics and Inelastic Neutron Scattering Spectra of CeNiSn

Yu. Kagan·K. A. Kikoin·A. S. Mishchenko
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Abstract

The microscopic theory of interaction between the heavy fermions and the crystal field excitations in Kondo lattices is presented. It is shown that the heavy-fermion spectrum scaled by the Kondo temperature $T_K$ can be modified by the crystal field excitations with the energy $Δ_{CF}$ provided the inequality $Δ_{CF}<T_K$ is realized. On the base of general description of excitation spectrum the detailed qualitative and quantitative explanation of anisotropic inelastic neutron scattering spectra and low-temperature specific heat of orthorhombic CeNiSn is given. The theory resolves the apparent contradiction between the metallic conductivity and the gap-wise behavior of thermodynamic properties and spin response of CeNiSn at low temperatures.

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Yu. Kagan, K. A. Kikoin, A. S. Mishchenko. 1996-11-11. Interplay between Heavy Fermions and Crystal Field Excitation in Kondo Lattices. Low-Temperature Thermodynamics and Inelastic Neutron Scattering Spectra of CeNiSn. https://doi.org/10.1103/physrevb.55.12348

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