We present magnetoresistance (MR) measurements performed on magnetic tunnel junctions in which one of the electrodes is a granular ferromagnetic film. These junctions exhibit a zero field resistance dip. The dip magnitude depends on the size of the grains. We interpret these results as a consequence of the orange peel effect between the continuous ferromagnetic film and the magnetic grains. The coupling is found to be much stronger than that between continuous ferromagnetic layers.
@article{arxiv.cond-mat/0307274,
title = {Orange Peel coupling in granular ferromagnetic films},
author = {D. Barness and A. Frydman},
journal= {arXiv preprint arXiv:cond-mat/0307274},
year = {2015}
}