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Specific heat of Ce_{0.8}La_{0.2}Al_{3} in magnetic fields: a test of the anisotropic Kondo picture

R. Pietri·K. Ingersent·B. Andraka
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Abstract

The specific heat C of Ce_{0.8}La_{0.2}Al_{3} has been measured as a function of temperature T in magnetic fields up to 14 T. A large peak in C at 2.3 K has recently been ascribed to an anisotropic Kondo effect in this compound. A 14-T field depresses the temperature of the peak by only 0.2 K, but strongly reduces its height. The corresponding peak in C/T shifts from 2.1 K at zero field to 1.7 K at 14 T. The extrapolated specific heat coefficient C/T(T->0) increases with field over the range studied. We show that these trends are inconsistent with the anisotropic Kondo model.

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R. Pietri, K. Ingersent, B. Andraka. 2000-07-26. Specific heat of Ce_{0.8}La_{0.2}Al_{3} in magnetic fields: a test of the anisotropic Kondo picture. https://doi.org/10.1103/physrevlett.86.1090

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