YBa2Cu3O7/La2/3Ca1/3MnO3 superconducting/ferromagnetic (SC/FM) multilayers have been studied by neutron reflectometry. Evidence for a characteristic difference between the structural and magnetic depth profiles is obtained from the occurrence of a structurally forbidden Bragg peak in the FM state. The comparison with simulated reflectivity curves allows us to identify two possible magnetization profiles: a sizable magnetic moment within the SC layer antiparallel to the one in the FM layer (inverse proximity effect), or a ``dead'' region in the FM layer with zero net magnetic moment. The former scenario is supported by an anomalous SC-induced enhancement of the off-specular reflection, which testifies to a strong mutual interaction of SC and FM order parameters.
@article{arxiv.cond-mat/0408311,
title = {Magnetic Proximity Effect in Perovskite Superconductor/Ferromagnet Multilayers},
author = {J. Stahn and J. Chakhalian and C. Niedermayer and J. Hoppler and T. Gutberlet and J. Voigt and F. Treubel and H. -U. Habermeier and G. Cristiani and B. Keimer and C. Bernhard},
journal= {arXiv preprint arXiv:cond-mat/0408311},
year = {2009}
}