Enhancement of coercive force in NiFe/FeRh-Ir bilayers grown on vicinal MgO(001) surfaces

Observations of enhanced coercive ve force in NiFe films exchange coupled w ith FeRh-Ir ordered alloy antiferromagnets epitaxially grown on MgO vicinal surfaces are reported. For NiFe thickness near 2.5 nm and miscut angle of 11.3 degrees the coercive force was increased by approx. 40% with respect t o the Aat NiFe/FeRh-Ir interface. The exact mechanism of this enhancement i s not completely understood. However, it seems related to an increased numb er of pinning centers at, the stepped interface. In addition to this effect we could also detect a usual step-induced uniaxial anisotropy. However, th e effect of this uniaxial anisotropy on the coercive force was much weaker than the enhancement due to the seeps at the NiFe/FeRh-Ir interface.