Thorough resistivity measurements on single crystals of CeZn${}_{11}$ under pressure $p$ and magnetic field $H$ are presented. At ambient pressure, CeZn${}_{11}$ orders antiferromagnetically at $T_N=2$ K. The pressure dependence of the resistivity reveals an increase of the Kondo effect. We determine the pressure evolution of the magnetic exchange interaction between conduction and localized $4f$ electrons. It qualitatively reproduces the pressure evolution of the magnetic ordering temperature $T_{O_1}$ (with $T_{O_1}=T_N$ at ambient pressure). In addition to $T_{O_1}$, a new anomaly $T_{O_2}$ appears under pressure. Both anomalies are found to increase with applied pressure up to $4.9$ GPa, indicating that CeZn${}_{11}$ is far from a pressure induced quantum critical point. Complex $T$-$H$ phase diagrams are obtained under pressure which reveal the instability of the ground state in this compound.

• Received 19 August 2013

DOI:https://doi.org/10.1103/PhysRevB.88.195114