Unusual Kondo-hole effect and crystal-field frustration in Nd-doped CeRhIn$_{5}$

TL;DR

This study explores how Nd doping affects the magnetic and electronic properties of CeRhIn$_{5}$, revealing a suppressed antiferromagnetic transition, crystal-field frustration, and the stabilization of Nd magnetic order, providing insights into magnetic doping effects in heavy-fermion systems.

Contribution

It demonstrates the impact of Nd substitution on the magnetic phase diagram of CeRhIn$_{5}$, highlighting crystal-field frustration and the deviation from expected percolation limits.

Findings

Antiferromagnetic transition temperature decreases linearly with Nd doping.

Extrapolated critical doping level is below the 2D percolation limit.

Nd magnetic order is stabilized near x~0.2, with T_N reaching 11 K.

Abstract

We investigate single crystalline samples of Ce$_{1-x}$Nd$_{x}$RhIn$_{5}$ by means of X-ray diffraction, microprobe, magnetic susceptibility, heat capacity, and electrical resistivity measurements. Our data reveal that the antiferromagnetic transition temperature of CeRhIn$_{5}$, $T_{N}^{\mathrm{Ce}} = 3.8$ K, is linearly suppressed with $x_{\mathrm{Nd}}$, by virtue of the "Kondo hole" created by Nd substitution. The extrapolation of $T^{\mathrm{Ce}}_{N}$ to zero temperature, however, occurs at $x_{c} \sim 0.3$, which is below the 2D percolation limit found in Ce$_{1-x}$La$_{x}$RhIn$_{5}$. This result strongly suggests the presence of crystal-field frustration effects. Near $x_{\mathrm{Nd}} \sim 0.2$, the Ising AFM order from Nd ions is stabilized and $T^{\mathrm{Nd}}_{N}$ increases up to $11$ K in pure NdRhIn$_{5}$. Our results shed light on the effects of magnetic doping in heavy-fermion antiferromagnets and stimulate the study of such systems under applied pressure.