Specific heat of Ce0.8La0.2Al3 in magnetic fields: A test of the anisotropic Kondo picture

The specific heat C of Ce0.8La0.2Al3 has been measured as a function of tem perature T in magnetic fields up to 14 T A large peak in C at 2.3 K has rec ently 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 re duces its height. The corresponding peak in C/T shifts from 2.1 K at zero f ield to 1.7 K at 14 T The extrapolated specific heat coefficient gamma = li m(T-->0)C/T increases with field over the range studied. We show that these trends are inconsistent with the anisotropic Kondo model.