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تسجيل مستخدم جديدUnusual Kondo-hole effect and crystal-field frustration in Nd-doped CeRhIn$_{5}$
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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.
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