Field-Induced Magnetic and Structural Domain Alignment in PrO2

TL;DR

This study investigates how magnetic and structural domains in PrO2 respond to applied magnetic fields, revealing irreversible magnetic changes linked to structural domain alignment and anisotropic susceptibility behavior.

Contribution

It provides new insights into the field-induced domain alignment in PrO2 and its effects on magnetic and structural properties, highlighting the role of structural domains in magnetic behavior.

Findings

Magnetic Bragg intensities change irreversibly with applied field.

Susceptibility shows strong anisotropy and anomalies at structural transition.

Structural domain alignment influences magnetic domain formation.

Abstract

We present a neutron diffraction study of the magnetic structure of single crystal PrO2 under applied fields of 0-6 T. As the field is increased, changes are observed in the magnetic Bragg intensities. These changes are found to be irreversible when the field is reduced, but the original intensities can be recovered by heating to T > 122 K, then re-cooling in zero field. The antiferromagnetic ordering temperature TN = 13.5 K and the magnetic periodicity are unaffected by the applied field. We also report measurements of the magnetic susceptibility of single crystal PrO2 under applied fields of 0-7 T. These show strong anisotropy, as well as an anomaly at T = 122 +/- 2 K which coincides with the temperature TD = 120 +/- 2 K at which a structural distortion occurs. For fields applied along the [100] direction the susceptibility increases irreversibly with field in the temperature range TN < T < TD. However, for fields along [110] the susceptibility is independent of field in this range. We propose structural domain alignment, which strongly influences the formation of magnetic domains below TN, as the mechanism behind these changes.