Study of the magnetic order in a Co/Cr multilayer by magnetic Bragg diffraction at the Co 2p resonance

We have measured the resonant scattering from an antiferromagnetic Co/Cr mu ltilayer at photon energies close to the cobalt 2p --> 3d transitions. The cobalt dielectric tensor has an anisotropic component, enhanced by resonanc e, which depends on the magnetic order and follows its modulation inside th e sample. We have studied the vertical distribution of this component throu gh the dependence of the reflectivity on the scattering angle. Using s-pola rized light, we have observed the signature of the cobalt-cobalt antiferrom agnetic coupling as an half-integer-order Bragg peak. Experimental results have been analyzed by numerical simulation. (C) 2000 Elsevier Science B.V. All rights reserved.