Marked Change in the Ground State of CeRu2Al10Induced by Small Amount of Rh Substitution

Abstract

We have investigated the marked change in the magnetic properties of CeRu2Al10 induced by a small amount of Rh substitution [Ce(Ru0.95Rh0.05)2Al10]. The magnetic susceptibility along the \(a\)-axis (χa) shows a large decrease with decreasing temperature after showing a sharp peak at \(T_{0}=24\) K and the high field magnetization for the magnetic field along the \(a\)-axis exhibits a spin-flop transition at \({\sim}13\) T. These indicate that the antiferromagnetic (AFM) order where the AFM moment is parallel to the \(a\)-axis takes place, which is consistent with the anisotropy of χa>χc>χb in the paramagnetic region, being different from the AFM order in CeRu2Al10. These results were analyzed by mean field calculation for the two-sublattice model using the crystalline electric field level scheme by Strigari et al. [Phys. Rev. B 86 (2012) 081105]. On the basis of both experimental and calculated results, we conclude that, by a small amount of Rh substitution with one extra \(4d\) electron, the large \(c\)–...