Magnetic Properties of Nanostructured CoPt and FePt Thin Films
نویسندگان
چکیده
Polycrystalline MgO underlayer films lead to different preferred orientations of 10 CoPt and FePt films after the annealing process, depending on the thickness of 10 films. 10 films with a thickness greater than 20 nm revealed mostly 10 [100] fiber texture and consequently in-plane anisotropy as determined by magnetic hysteresis. Strong perpendicular anisotropy due to the 10 [001] fiber texture was obtained for thicknesses below 10 nm. The M curve showed strong intergranular exchange coupling. The angular variation of coercivity showed the possibility of both domain wall motion and a rotational mechanism of magnetization reversal.
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