Antiferromagnetic correlations in the cubic heavy fermion compound CeInCu2

CeInCu₂ is a heavy fermion compound close to magnetic instability. The electrical resistivity has aT ² behaviour between 1 and 2.5 K. and the AC field susceptibility has a faint maximum at 0.9 K, indicating the onset of coherence near 1 K for this compound. The magnetoresistance keeps a negative sign down to 0.3 K. Neutron inelastic scattering give a crystal field splitting of 90 K, with a doublet ground state, and a residual quasielastic linewidth of 0.3 meV.We have studied the resistivity, susceptibility and specific heat of some dilute solutions La_1–xCe_xInCu₂ and Y_1–xCe_xInCu₂. The spin-dependent part of the resistivity may be decomposed into a single impurity term plus a pair interaction term, the magnitude of which folows a Curie-Weiss law, as in classical spin glassesCuMn orAuFe.The magnetisation and susceptibility at low temperatures may be represented within the resonant level model, taking into account antiferromagnetic interactions. Finally, the specific heat of CeInCu₂ shows a bump near 2.3 K, absent for dilute solutions, which may also be interpreted by introducing a magnetic interaction term.