| Abstract
| - Anodized alumina membranes, prepared by a three-step anodization process, were used as templates to grow Ni, Co, and Fe nanowires with 250−300 nm diameter. The competition between shape anisotropy and dipolar interactions seems to be responsible for the difference in magnetic behavior observed in the different metals.
- Anodized alumina membranes (AAMs) were synthesized by a three-step electrochemical anodizationof aluminum. The anodization results in a hexagonally pseudo-ordered 2D array of nanochannels. TheAAMs were used as templates to grow Ni, Co, and Fe nanowires, with diameters in the range of 250−300 nm, by electrodeposition. The AAM appears to be amorphous, while the metal nanowires arepolycrystalline. The angular dependence of the coercivity, HC, of the Ni nanowires presents a smoothvariation from a μoHC = 5.5 mT when the field is applied perpendicular to the wires to μoHC = 53 mTwhen the field is applied parallel to them. However, the Co and Fe nanowires exhibit a peak in theangular dependence of HC for fields applied close to the AAM plane (i.e., perpendicular to the wires).The competition between shape anisotropy and dipolar interactions between the nanowires seems to beresponsible for the difference in magnetic behavior between the different metals.
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