Magnetic order and the spin-flop transition in Fe/Cr superlattices

We have studied the structural and magnetic properties of MBE-prepared epit axial Fe/Cr(001) oriented superlattices. The samples consist of 20 periods with 25 nm Fe and 1.3 nm Cr individual layer thicknesses. The samples were characterized by X-ray diffraction, while: the magnetic properties were det ermined by magnetoresistivity, magnetooptical Kerr effect, and polarized ne utron reflectivity measurements. The transition from antiparallel to parall el alignment of the magnetizations in adjacent Fe layers was investigated u sing polarized neutron reflectivity measurements while applying a held para llel to the layers. A spin-flop transition due to the fourfold anisotropy i n the Fe layers was observed at a field of 200 Oe. (C) 2000 Elsevier Scienc e B.V. All rights reserved.