Thermal conductivity of CeNiAl4 Kondo lattice

The studies of thermal conductivity κ of CeNiAl4 Kondo lattice are reported. For comparison, the same measurement has been made on a sample of LaNiAl4. The measured κ of CeNiAl4 compound increases with increasing temperature. The Lorentz number L/L0 increases rapidly on cooling and reaches a maximum value at T = 12 K. With further decrease of temperature the L/L0 becomes smaller. The magnetic contribution to the thermal resistivity Wmag was separated and it was shown that the product WmagT has a logT-behavior at high temperature region, suggesting of Kondo effect similar to that observed as for magnetic resistivity ρmag.

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►  WmagT has a logT-behavior from 240 K to 300 K, indicate on presence of Kondo effect.
►  The logT was observed also for ρmag, showing further proof for a Kondo effect. 
► For CeNiAl4 the TK is lower than the overall CEF splitting energy ΔCEF.