Change in Unusual Magnetic Properties by Rh Substitution in CeRu₂Al₁₀

Abstract

We have studied the Rh substitution (electron doping) effect in the Kondo semiconductor CeRu2Al10, which orders antiferromagnetically below (\(T_{0}=27\) K), by specific heat \(C\), magnetic susceptibility χ, electrical resistivity ρ, and Hall resistivity ρ\(_{\text{H}}\) measurements of Ce(Ru1-xRhx)2Al10 (\(x=0.12\), 0.2, 0.23, 0.34) single crystals. \(T_{0}\) decreases monotonically with an increase in \(x\). In addition, new anomalies occur at \(T_{1}\sim 6.5\) and \(T_{2}\sim 3.0\) K in all the Rh substitution samples. However, \(T_{1}\) and \(T_{2}\) are almost independent of \(x\). The shape of the anomaly at \(T_{0}\) in χ\((T)\) changes with Rh substitution, which implies the reorientation of the ordered moment. These phenomena indicate that the magnetic properties of CeRu2Al10 are strongly associated with the number of \(4d\) electrons.