Field-induced magnetic and structural domain alignment in PrO2 -: art. no. 024416

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 recooling in zero field. The antiferromagnetic ordering temperature T-N=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 T-D=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 T-N