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Thermodynamics of CeNiSn at low temperatures and in weak magnetic fields

K. A. Kikoin·M. N. Kiselev·A. S. Mishchenko·A. de Visser
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Abstract

Detailed experimental and theoretical studies of the low-temperature specific heat, magnetic susceptibility, thermal expansion and magnetostriction of the orthorhombic compound CeNiSn are presented. All anomalies observed in the thermodynamic and magnetic properties of CeNiSn are explained in a framework of a model of metallic Kondo lattice with well developed spin-liquid-type excitations. The pseudogap behavior of these excitations appears due to interplay between spin-fermions and soft crystal-field (CF) states. The thermodynamic relations for the spin liquid are derived. Together with the explanation of inelastic neutron scattering spectra given earlier within a same approach these studies of the low-temperature thermodynamics and magnetic response give a consistent description of the nature of anomalies in the low-temperature thermodynamics of perfect and imperfect CeNiSn crystals.

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K. A. Kikoin, M. N. Kiselev, A. S. Mishchenko, A. de Visser. 1999-03-14. Thermodynamics of CeNiSn at low temperatures and in weak magnetic fields. https://doi.org/10.1103/physrevb.59.15070

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