The role of hyperfine coupling in magnetic and quadrupolar ordering of Pr3Pd20Si6

TL;DR

This study investigates how hyperfine interactions influence magnetic and quadrupolar orderings in Pr3Pd20Si6, revealing nuclear spins' involvement in the magnetic ground state through specific heat and susceptibility measurements.

Contribution

It provides the first detailed analysis of hyperfine coupling effects in Pr3Pd20Si6, highlighting nuclear spins' role in magnetic ordering.

Findings

Nuclear spins participate in the AFM ordering.

Hyperfine level scheme matches experimental data.

Distinct AFM and AFQ orderings identified.

Abstract

We study the ternary clathrate Pr3Pd20Si6 in specific heat and AC-susceptibility measurements on a high-quality single crystal, distinguishing antiferromagnetic (AFM) and antiferroquadrupolar (AFQ) ordering on two sublattices of inequivalent Pr sites. The specific heat shows the direct involvement of nuclear spin degrees of freedom in the AFM ordering, which is well supported by our calculation of the hyperfine level scheme without adjustable parameters. Pr3Pd20Si6 is therefore one of the rare materials where the nuclear moments are involved in the formation of the magnetic ground state.