In-plane magnetic anisotropy in antiferromagnetic YBa 2Cu 3O 6+ x

Abstract

A neutron diffraction study of the magnetic field dependence of the magnetic Bragg reflections of single crystals of YBa 2Cu 3O 6+ x ( x=0.05 and 0.34) has shown that the magnetic moments originally along the [100] (or [010]) axis turn toward the [110] direction perpendicular to the magnetic field applied along [1–10]. The very small in-plane anisotropy is evaluated to Δ x y =5×10 −5 meV.