Recently, we have demonstrated that a large ferromagnetic moment can be induced at theinsulating barrier (La0.3Ca0.7MnO3 (LC7MO)) separating two ferromagnetic-metallicLa0.7Ca0.3MnO3 (LC3MO) manganese perovskite oxides in LC3MO/ LC7MO/ LC3MO trilayerswhen the magnetic alignment between electrodes is parallel. To explore the nature of thismagnetic state we propose a polarized neutron reflectometry experiment with polarizationanalysis. We aim at assessing if the magnetization of the barrier goes to zero in the antiparallel(AP) state, which would indicate that the moment is induced by spin canting at the FM electrodesor if the moment remains what would indicate an intrinsic ferromagnetism of the barrier layer.Simulations show significant spin asymmetry in the q range 0.06- 0.12 what indicates that high fluxof the POLREF instrument will be necessary.