Magnetoresistance in Fe$_{1-x}$Ga$_x$ thin films presenting striped magnetic pattern: the role of closure domains and domain walls

Abstract: In this work we show the existence of closure domains in Fe$_{1-x}$Ga$_x$ thin films featuring a striped magnetic pattern and study the effect of the magnetic domain arrangement on the magnetotransport properties. By means of X-ray resonant magnetic scattering, we experimentally demonstrate the presence of such closure domains and estimate their sizes and relative contribution to surface magnetization. Magnetotransport experiments show that the behavior of the magnetoresistance depends on the measurement geometry as well as on the temperature. When the electric current ows perpendicular to the stripe direction, the resistivity decreases when a magnetic field is applied along the stripe direction (negative magnetoresistance) in all the studied temperature range, and the calculations indicate that the main source is the anisotropic magnetoresistance. In the case of current flowing parallel to the stripe domains, the magnetoresistance changes sign, being positive at room temperature and negative at 100 K. To explain this behavior, the contribution to magnetoresistance from the domain walls must be considered besides the anisotropic one.