A New Multipolar Ordering Compound, Rare-Earth Palladium Bronze PrPd3S4

Abstract

Specific heat and magnetization measurements were performed on single crystalline PrPd 3 S 4 . A λ-type anomaly at T M = 1.56 K in the specific heat shifts to higher temperatures by magnetic fields, begins to shift to lower temperatures above 2 T, and disappears above 3.6 T. The 4 f ground state of Pr 3+ was deduced to be a magnetic triplet. Below T M , the magnetic susceptibility increases while no spontaneous magnetization appears. These results strongly reveal that PrPd 3 S 4 shows a multipolar ordering at T M . The most probable ordering state for PrPd 3 S 4 is an antiferroquadrupolar (AFQ) ordering since the B – T phase diagrams are of the “re-entrant” type, which is typical for AFQ ordering compounds.