Unusual Kondo-hole effect and crystal-field frustration in Nd-doped CeRhIn5

We investigate single crystals of Ce1-xNdxRhIn5 by means of x-ray-diffraction, microprobe, magnetic susceptibility, heat capacity, and electrical resistivity measurements. Our data reveal that the antiferromagnetic transition of CeRhIn5, at TNCe=3.8 K, is linearly suppressed with xNd. We associate this effect with the presence of a "Kondo hole" created by Nd substitution. The extrapolation of TNCe to zero temperature, however, occurs at xc∼0.3, which is below the two-dimensional percolation limit found in Ce1-xLaxRhIn5. This result strongly suggests the presence of a crystal-field induced magnetic frustration. Near xNd∼0.2, the Ising antiferromagnetic order from Nd3+ ions is stabilized and TNNd increases up to 11 K in NdRhIn5. Our results shed light on the effects of magnetic doping in heavy-fermion antiferromagnets and stimulate the study of such systems under applied pressure.