Coupling of antiferromagnetic films through an insulator : Study of Cr/MgO/Cr multilayers

Neutron diffraction is the central technique of this project since it is an efficient tool to scan the magnetism of matter. It is used here to analyze the peculiar magnetic properties of trilayers of Cr films separated by a thin MgO layer. The anomalies in comparison to isolated Cr films are attributed to a coupling between the magnetic layers through the insulator. This work aims hence at characterizing this effect by observing the influence of various parameters of the system (barrier thickness, temperature, or magnetic field) on the coupling effect. A better understanding of the magnetism of this system and the characterization of the observed effect as a phenomenon of tunnel coupling (whose existence depends on the barrier thickness) should be achieved by analysis of the structural and magnetic characterization experiments. Motivations