Polarized neutron reflectivity measurements of a ferromagnetic [(LaMnO3)11.8/(SrMnO3)4.4]6 superlattice reveal a modulated magnetic structure with an enhanced magnetization at the interfaces where LaMnO3 was deposited on SrMnO3 (LMO/SMO). However, the opposite interfaces (SMO/LMO) are found to have a reduced ferromagnetic moment. The magnetic asymmetry arises from the difference in lateral structural roughness of the two interfaces observed via electron microscopy, with strong ferromagnetism present at the interfaces that are atomically smooth over tens of nanometers. This result demonstrates that atomic-scale roughness can destabilize interfacial phases in complex oxide heterostructures.
@article{arxiv.0709.1715,
title = {Magnetically asymmetric interfaces in a (LaMnO$_3$)/(SrMnO$_3$) superlattice due to structural asymmetries},
author = {S. J. May and A. B. Shah and S. G. E. te Velthuis and M. R. Fitzsimmons and J. M. Zuo and X. Zhai and J. N. Eckstein and S. D. Bader and A. Bhattacharya},
journal= {arXiv preprint arXiv:0709.1715},
year = {2009}
}