Electrical resistivity study of CeZn11: Magnetic field and pressure phase diagram up to 5 GPa

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.