Local investigation of magnetism at R and In sites in RNiIn (R=Gd, Tb, Dy, Ho) compounds

Abstract

The local magnetism at R and In sites in RNiIn (R=Gd, Tb, Dy, Ho) compounds was investigated by measuring hyperfine interactions via perturbed gamma-gamma angular correlation (PAC) technique using La140–Ce140 and In111–Cd111 probe nuclei. PAC measurements carried out below respective TC for each compound showed a combined electric quadrupole plus magnetic dipole interaction for Cd111 probe at In sites and a pure magnetic interaction for Ce140 at R sites. The temperature dependence of the magnetic hyperfine field (Bhf) shows that, whereas the Bhf values at rare-earth sites measured with Ce140 drop to zero at temperatures around the expected TC for each compound, the respective fields at In sites measured with Cd111 drop to zero at lower temperatures. The difference between the temperatures at which Bhf is zero for Ce140 and Cd111 probes when compared with TC of each compound shows that this difference decreases with decreasing TC values. The results are discussed in terms of the Ruderman-Kittel-Kasuya-Yosida model for magnetic interactions and the crystalline electric field.