Pressure-induced magnetic instability in Ce2Rh3Ge5

A pressure-induced magnetic-nonmagnetic transition in an antiferromagnet Ce2Rh3Ge5 has been investigated by the measurements of the resistivity ρ, magnetic susceptibility χ, and specific heat on a single crystal down to 0.3 K. With increasing pressure, the Ne?el temperature TN is suppressed and disappears at Pc=0.45 GPa. For P>Pc, the deviation from the Fermi-liquid behavior is observed in both ρ(T) and χ(T): ρ(T)=ρ0+ATn (n≅1.45) and χ(T)=χ0-DTm (m≅0.27). Even for P>3Pc both n and m hardly change, i.e., no recovery of the Fermi-liquid state. This fact is in contrast with the recovery in many of Ce-based antiferromagnets at P>2Pc. The magnetization hardly decreases with pressure up to 1.2 GPa, suggesting that the cerium local moments still remain even far from the quantum critical point. Moreover, the Kondo temperature TK increases weakly from 10 K at P=0 to 13 K at P=0.57 GPa. These findings indicate the important role of short-range magnetic correlations in the revised Doniach phase diagram