Anomalies in Pr-based compounds

Abstract

Anomalies in the properties of the compound PrCu₂Si₂ are reported. This compound exhibits an unexpectedly high Néel temperature. The explanation in terms of the role of electric quadrupole alignment, offered for the marginal breakdown of de Gennes scaling in isomorphous heavy rare-earth members, is found to be not applicable to PrCu₂Si₂. Heavy-fermion-like like behaviour (a phenomenon unexplored for Pr-based alloys) is also seen. Arguments in favor of the possible existence of electric quadrupolar fluctuations in this compound are discussed. Finally, some comments on the well-known anomalies in PrBa₂Cu₃O₇ are made taking the above results into account.