Magnetic anisotropy and reversal in epitaxial Fe/MgO(001) films

Abstract

We investigate the magnetization reversal in Fe/MgO(001) films with fourfold\nin-plane magnetic anisotropy and an additional uniaxial anisotropy whose\norientation and strength are tuned using different growth geometries and post\ngrowth treatments. The previously adopted mechanism of 180^{o} domain wall\nnucleation clearly fails to explain the observed 180^{o} magnetization\nreversal. A new reversal mechanism with two successive domain wall nucleations\nconsistently predicts the switching fields for all field orientations. Our\nresults are relevant for a correct interpretation of magnetization reversal in\nmany other epitaxial metallic and semiconducting thin films.\n