Lattice effects in the ferromagnetic insulating phase of manganites

The origin of the ferromagnetic insulating (FMI) phase observed at low temperature in a large variety of manganites is addressed by using x-ray absorption spectroscopy. The variations in the Mn L2,3 and O K-edge x-ray absorption and circular dichroism spectra as a function of temperature are consistent with a carrier localization and localized lattice distortions associated with this phase.