Low Temperature Magnetic Hysteresis in PdFe Nanowire Arrays

M.S. VIQUEIRA; G. POZO LÓPEZ; A.M. CONDÓ; J.M. LEVINGSTON; S.E. URRETA; L.M. FABIETTI

Puerto Iguazú, Misiones

Congreso; 13er Congreso SAM - CONAMET, Congreso Internacional en Ciencia y Tecnología de Metalurgia y Materiales; 2013

SAM Asociación Argentina de Materiales

Pd1-xFex (0.2 < x < 1) nanowires with diameters between 20 nm and 70 nm are fabricated by AC electrodeposition into self-assembled alumina templates. The nanowires are polycrystalline, with a mean length of about 1μm; samples with high Fe contents are bcc Fe(Pd) solid solutions while the Pd-rich ones contain a major fcc Pd(Fe) phase and a few, small γ-Fe crystals. In the as deposited condition, the nanowire arrays (the alumina membrane filled by the metallic nanowires) are ferromagnetic, exhibiting an easy magnetization axis parallel to the wire length, mainly attributed to a relatively large shape anisotropy. Coercivity and remanence both increase with the Fe content. The effect of the diameter on the hysteresis behavior of the nanowire arrays is more evident in samples containing lower amounts of Pd. Coercivity and remanence slowly increase at low temperature, in agreement with the predictions for an effective shape anisotropy controlled magnetic hardness.