نبذة مختصرة : The effective magnetic anisotropy field Heff of Fex Ni(100-x) (x = 15, 25, 38) nanowires of 65 nm diameter forming ordered arrays within dense alumina templates of ∼35% porosity, was determined. Different values for Heff were obtained depending on the determination method, which were: magnetization evolution along major hysteresis loops; ferromagnetic resonance at 34 GHz; and magnetization switching by curling nucleation (through angular variation of the coercive field). Heff values determined from magnetization measurements differ from those arising from FMR measurements, being these latter quite smaller in every case. No evidence of an easy plane behavior was found, as theoretically predicted for high porosity arrays as ours. These results suggest that new internal degrees of freedom need to be considered for the effective anisotropy description in quasistatic hysteresis loops, during polarization reversal and in ferromagnetic resonance dynamic processes, to understand and model these experimental findings. We discuss possible causes. ; Fil: Almeira, Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina ; Fil: Meneses, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina ; Fil: Milano, Julian. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina ; Fil: Ramos, Carlos Alberto. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. ...
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