  The structural and magnetic properties of a series of superlattices
consisting of two ferromagnetic metals La$_{0.7}$Sr$_{0.3}$MnO$_3$ (LSMO) and
SrRuO$_3$ (SRO) grown on (001) oriented SrTiO$_3$ are studied. Superlattices
with a fixed LSMO layer thickness of 20 unit cells (u.c.) and varying SRO layer
thickness show a sudden drop in magnetization on cooling through temperature
where both LSMO and SRO layers are ferromagnetic. This behavior suggests an
antiferromagnetic coupling between the layers. In addition, the samples having
thinner SRO layers (n \TEXTsymbol{<} 6) exhibit enhanced saturation
magnetization at 10 K. These observations are attributed to the possible
modification in the stereochemistry of the Ru and Mn ions in the interfacial
region.
