Superconductivity and anomalous normal state in the CePd2Si2/CeNi2Ge2 system

The unconventional nonmagnetic metal CeNi2Ge2 is characterised at ambient pressure by temperature dependences of the specific heat and of the resistivity which deviate strongly from standard Fermi-liquid predictions and are reminiscent of the behaviour observed in its sibling system CePd2Si2 above the critical pressure at which magnetic order is suppressed. We have explored the CePd2Si2/CeNi2Ge2 phase diagram in a series of resistivity measurements under high hydrostatic pressure, p. At p > 15 kbar, a new superconducting transition appears below 220 mK in CeNi2Ge2 and shifts to higher temperatures with increasing pressure, reaching similar to 400 mK p similar to 26 kbar.