Electrical Resistivity Measurements on PrPb3 under High Pressures

PrPb 3 shows antiferroquadrupolar (AFQ) ordering below T Q = 0.4 K. Recently, Onimaru et al. revealed the existence of spatially modulated AFQ structure by neutron diffraction technique. Suggestively, an indirect RKKY-type quadrupolar interaction should play an important role in this system. In the present work, in order to examine stability of the AFQ ordered state in pressure, we carried out electric resistivity measurements under high pressures up to 7.3 GPa and at temperatures down to 0.3 K. We found that a kink observed at T Q in ρ( T ) gradually rose with increasing pressures up to 5 GPa, indicating that the AFQ ordered state would be stabilized by applying pressure. However, further increases in pressure above 5 GPa result in disappearance of the kink which should be observed at T Q .