Journal of Magnetism and Magnetic Materials vol:240 issue:1-3 pages:514-516
The layer magnetisation reorientation transition (spin-flop. SF) was studied in an artificial layer antiferromagnet (AF), namely in MgO(0 0 1)/[Fe-57(2.6 nm)/Cr(1.3 nm)](20) epitaxial superlattice (SL) by synchrotron Mossbauer reflectometry and Kerr effect (SMOKE). The SF occurs simultaneously in the entire SL stack (bulk SF) in an increasing field of H-SF = 13 mT along the easy direction parallel to the layer magnetisations. It is recognised by the kink in the SMOKE loop and by the sharp up-rise of the AF Bragg peak in the delayed Mossbauer reflectivity. The moderate value of observed H-SF is compared with estimations from a spin-chain model and interpreted as due to intraplane domain-wall motion during SF. (C) 2002 Elsevier Science B.V. All rights reserved.