^{63,65}Cu NMR and NQR evidence for an unusual spin dynamics in PrCu_2 below 100 K

TL;DR

This study uses Cu NMR and NQR techniques to investigate PrCu₂, revealing unusual spin dynamics below 100 K and challenging previous claims of magnetic order at 65 K, highlighting complex interactions in the system.

Contribution

It provides new NMR/NQR evidence showing the absence of magnetic order at 65 K and discusses the complex spin dynamics in PrCu₂, contrasting with prior muon spin rotation findings.

Findings

No confirmation of magnetic order at 65 K.

Unusual spin dynamics below 100 K.

Complex dipolar and quadrupolar interactions.

Abstract

We report the results of a $^{63,65}$Cu NMR/NQR study probing the intermetallic compound PrCu$_2$. The previously claimed onset of magnetic order at 65 K, indicated in a $\mu$SR study, is not confirmed. Based on our data we discuss different possible reasons for this apparent discrepancy, including a non negligible influence of the implanted muons on their environment. Competing dipolar and quadrupolar interactions lead to unusual features of the magnetic-ion/conduction-electron system, different from those of common intermetallics exhibiting structural or magnetic instabilities.