Asymmetric domain nucleation and unusual magnetization reversal in ultrathin Co films with perpendicular anisotropy.
نویسندگان
چکیده
We report unexpected phenomena during magnetization reversal in ultrathin Co films and Co/Pt multilayers with perpendicular anisotropy. Using magneto-optical Kerr microscopy and magnetic force microscopy we have observed asymmetrical nucleation centers where the reversal begins for one direction of the field only and is characterized by an acute asymmetry of domain-wall mobility. We have also observed magnetic domains with a continuously varying average magnetization, which can be explained in terms of the coexistence of three magnetic phases: up, down, and striped.
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عنوان ژورنال:
- Physical review letters
دوره 98 11 شماره
صفحات -
تاریخ انتشار 2007