On the low-temperature magnetic properties of CuO single crystals

Abstract

The origin and magnitude of a paramagnetic contribution to the CuO susceptibility at T<150 K are studied by analysing electron paramagnetic resonance and static magnetic susceptibility measurements carried out on a set of CuO single crystals. This has allowed the authors to confirm a previous supposition about the behaviour of the susceptibility for T<150 K. The asymptotic finite value of the susceptibility in the antiferromagnetic phase is also discussed by means of a crystal-field calculation which seems to rule out contributions to the local magnetic moments from incompletely quenched orbital angular moments of the Cu2+ ions. Preliminary magnetization measurements suggest the presence of weak ferromagnetism, which may explain the unusual behaviour of the CuO susceptibility.