No abstract

Complementary multiscale magneto-optical studies based on the polar Kerr effect are carried out on an ultrathin cobalt wedge covered with a silver wedge and subsequently with the Au thick layer. A few monolayers of Ag are found to have a substantial effect on magnetic anisotropy, the coercivity field, and Kerr rotation. The silver overlayer thickness-driven magnetic reorientation from easy axis to easy plane generates a new type of 90 degrees magnetic wall for cobalt thicknesses between 1.3 and 1.8 nm. The tuning of the wall width in a wide range is possible. Tailoring of the overlayer structure can be used for ultrathin film magnetic patterning.

No abstract

We show, combining simulations and analytical study, the evolution of magnetization distributions in ultrathin film with in-plane fields (H ʈ ) and changes of magnetic anisotropy characterized by the quality factor, Q. Reconstruction of the distributions and their new types near Q or H ʈ -induced reorientation phase transitions, from a domain structure ͑DS͒ with perpendicular magnetization into a state with in-plane magnetization, are reported. Sinusoidal-like DS exist for H ʈ larger than the anisotropy field and for QϽ1. A minimal 8l ex DS period is predicted (l ex is the exchange length͒.