The magnetic and electronic modifications induced at the interfaces in ${\left({\text{SrMnO}}_3\right)}_n/{\left({\text{LaMnO}}_3\right)}_{2n}$ superlattices have been investigated by linear and circular magnetic dichroism in the $\text{Mn}{L}_{2,3}$ x-ray absorption spectra. Together with theoretical calculations, our data demonstrate that the charge redistribution across interfaces favors in-plane ferromagnetic (FM) order and $e_g\left(x^2-y^2\right)$ orbital occupation, in agreement with the average strain. Far from interfaces, inside ${\text{LaMnO}}_3$, electron localization and local strain favor antiferromagnetism (AFM) and $e_g\left(3z^2-r^2\right)$ orbital occupation. For $n=1$ the high density of interfacial planes ultimately leads to dominant FM order forcing the residual AFM phase to be in-plane too, while for $n\ge 5$ the FM layers are separated by AFM regions having out-of-plane spin orientation.

• Received 3 July 2009

DOI:https://doi.org/10.1103/PhysRevB.80.140405