Speaker
Description
We study the effect of antiferromagnetic buffer layers (insulating LaMnO$_3$ and metallic La$_{0.45}$Sr$_{0.55}$MnO$_3$) on the magnetism of epitaxial ultrathin La$_{0.8}$Sr$_{0.2}$MnO$_3$ (LSMO) films, grown by molecular beam epitaxy and studied by x-ray magnetic circular dichroism as a function of temperature and thickness. We find a non-monotonic variation of the moment in the LSMO films grown on LaMnO$_3$ (which display a magnetic moment) and a bulk-like moment at 5 unit cells thickness; films grown on La$_{0.45}$Sr$_{0.55}$MnO$_3$ seem to adopt the properties of the buffer layer (reduced moments). The results highlight the role of the buffer layer properties in understanding the effects of charge/spin exchange for controlling the magnetic properties of ultrathin LSMO.
