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We put forward a new presentation of the theory of off-specular scattering of polarized neutrons from magnetic multilayers within the distorted wave Born approximation developed by one of the authors. In this presentation, a clear separation is made between (1) the structure factors, model dependent, and (2) the optical coefficients and the efficiencies of the polarizer and the analyzer, model independent. It therefore permits an easy plugging in of any particular model of structural and magnetic correlations. For a test, we show simulations of off-specular scattering from magnetic domains in multilayers exhibiting anti-ferromagnetic coupling, a situation encountered in the literature. [Copyright &y& Elsevier]

We show a measurement of off-specular polarized neutron scattering from an Fe/Cr/Fe trilayer inside which a second-order neutron resonance has been excited, i.e. where the probability to find a neutron was maximum at both Fe/Cr interfaces. Simulating the data in the framework of the Distorted Wave Born Approximation showed the presence of structural and magnetic fluctuations. Magnetic fluctuations in the vicinity of the Fe/Cr interfaces can be explained if one considers the anti-ferromagnetic structure of Cr and structural roughness. [Copyright &y& Elsevier]

Abstract: Polarized neutron reflectivity (PNR) studies have been performed on granular multilayers [Co80Fe20(tn )/Al2O3 (3nm)] m . For a non-percolating superferromagnetic (SFM) sample (tn =1.3nm) no spin-flip (SF) scattering was observed, measured at various points of the hysteresis, confirming that the magnetization reversal is achieved merely by domain nucleation and growth. For a percolated sample (tn =1.6nm) an oscillating magnetization depth profile from FeCo layer to FeCo layer along the multilayer stack was observed around the coercive field. The competition between long-range dipolar, short-range Néel and external field interactions apparently give rise to such a modulated magnetization depth profile in these magnetic multilayers. [Copyright &y& Elsevier]

The surface layer of an epitaxial Fe/Cr multilayer system has been structured lithographically into stripes with 1 μm period. Polarized neutron reflectometry and diffuse scattering under grazing incidence measurements show strongly enhanced domain formation compared to the unstructured sample. The domains are correlated throughout the layers. The lateral domain size is partly the period of the stripe pattern of the surface layer, and partly the double. [Copyright &y& Elsevier]