Polarizing Ti$_{1-u}$X$_u$/Fe$_x$Co$_y$V$_z$ supermirrors
Résumé
Polarizing multilayers and supermirrors composed of $ {\rm Ti}_{1-u} {\rm X}_u $ and $ {\rm Fe}_x {\rm Co}_y {\rm V}_z $ have been produced using DC-magnetron sputtering. The structure of the samples has been characterized by neutron and X-ray diffraction. The results show that the smoothness of the layers can be improved by adding controlled amounts of alloying materials, an effect that has already been observed for Ni/Ti supermirrors. Flipping ratios of more than 40 and reflectivities of more than 85\% at twice the critical angle of Ni are obtained, depending on the concentrations of the materials, $ u,x,y,z. $ The sputtering process can be optimized in such a way that the magnetization within the plane is anisotropic thus allowing a saturation of the samples in low fields.