Influence of Asymmetric Interface Coupling on Properties of LaCoO3/LaMnO3 Bilayers

Abstract:

The LaCoO₃/LaMnO₃ bilayers epitaxial film grown on (100) SrTiO₃ substrates were obtained by a simple polymer assisted sol-gel deposition method. Growing a LaCoO₃ layer on the top of LaMnO₃ leads to the asymmetric interface coupling at the interface layer due to their difference in strucural symmetry, and reduces the ferromagnetic transition temperature caused by the asymmetric interface coupling effect from 262 K to 200 K. In addition, compared with the coercive field of isolated LaMnO₃ film, the coercive field observed in the bilayers is increased by ~500% due to a strong ferromagnetic Mn-O-Co double exchange interaction at the interface. The results demonstrate that the recombination of multilayer films with different properties provides a new way to design functional materials for fundamental studies or demanding applications.

Key words:perovskite-type bilayers;ferromagnetic transition;coercive field;interface coupling effect