  Resonant soft x-ray absorption measurements at the O K edge on a
SrMnO3/LaMnO3 superlattice show a shoulder at the energy of doped holes, which
corresponds to the main peak of resonant scattering from the modulation in the
doped hole density. Scattering line shape at the Mn L3,2 edges has a strong
variation below the ferromagnetic transition temperature. This variation has a
period equal to half the superlattice superperiod and follows the development
of the ferromagnetic moment, pointing to a ferromagnetic phase developing at
the interfaces. It occurs at the resonant energies for Mn3+ and Mn4+ valences.
A model for these observations is presented, which includes a double-exchange
two-site orbital and the variation with temperature of the hopping frequency
tij between the two sites.
