Nuclear Spin–Lattice Relaxation Study for 4fElectron State in CeT2Al10(T = Ru, Os, and Fe): Comparison with RKKY System NdRu2Al10

Abstract

In order to uncover the \(4f\) electron state as a background for the emergence of the novel phase below \(T_{0}\) in CeT2Al10 (T = Ru, Os), the nuclear spin–lattice relaxation rate \(1/T_{1}\) in the well-localized RKKY system NdRu2Al10 was measured and compared with that in CeRu2Al10. The value of \(1/T_{1}\) in NdRu2Al10 with \(T_{\text{N}}=2.4\) K, which follows de Gennes scaling from \(T_{\text{N}}=16\) K in GdRu2Al10, shows a characteristic \(T\)-dependence for localized systems, \(1/T_{1}=a/(b+cT)\), with the constants \(a\), \(b\), and \(c\). On the other hand, in CeRu2Al10, \(1/T_{1}\) at temperatures higher than \(T^{*}\sim 60\) K also follows the same function if the Korringa relaxation is subtracted, indicating that the Ce \(4f\) electron in CeRu2Al10 is in a localized state at least down to \(T^{*}\). Below the characteristic temperature \(T^{*}\), the downward deviation of \(1/T_{1}\) from the above function might be ascribed to the beginning of Kondo coherence as proposed previously. Furthe...