Specific Heat of a New Dense-Kondo System CeTIn (T=Ni, Pd, Pt)

Abstract

Specific heat of a newly-found dense-Kondo system CeTIn (T=Ni, Pd, Pt) has been measured between 60 mK and 80 K. For CePdIn and CePtIn, the ratio of specific heat to temperature, C / T , increases remarkably below 10 K, indicating the heavy-fermion nature. On the other hand, no enhancement of C / T is observed for CeNiIn, suggesting the valence fluctuating state. A sharp peak in C / T is observed at 1.7 K for CePdIn, which is ascribed to an antiferromagnetic transition, whereas CePtIn does not show any signs of phase transition at least down to 60 mK. The variety of low-temperature behavior in CeTIn is discussed in terms of competition between the Kondo state and the RKKY interaction.