Successive Magnetic Transitions in the Heusler Heavy-Fermion System CeInCu₂

Abstract

The ground state of a heavy-fermion compound CeInCu₂ of the cubic Heusler structure has been investigated by ⁶³Cu and ¹¹⁵In nuclear magnetic resonance. From the temperature dependence of the NMR spectra, two antiferromagnetic-like transitions have been found at T_N1=1.6 K and successively at T_N2=1.1 K. The first transition, which Takagi et al. already observed, is very sensitive to the external magnetic field, whereas the second one found in this study yields a rather stable magnetic moment whose magnitude at 0.3 K was roughly estimated to be the order of 0.1 μ_B/Ce.