A method is presented for the preparation of a three-dimensional magnetic data storage material system. The major ingredients are an inert nanoporous matrix prepared by anodization and galvanic plating of magnetic and non-magnetic metals in wire shape inside the cylindrical pores. The individual nanomagnets consist of a nickel–cobalt alloy, the composition of which is tuned systematically by adjusting the electrolytic bath composition at one optimal applied potential. The lowest magnetocrystalline anisotropy is obtained at the composition Ni60Co40, as quantified by superconducting quantum interference device magnetometry. Wires of this composition experience a pinning-free propagation of magnetic domain walls, as determined by single-wire magneto-optical Kerr effect magnetometry. Adding copper into the electrolyte allows one to generate segments of Ni60Co40 separated by non-magnetic copper. The segment structure is apparent in individual nanowires imaged by scanning electron microscopy, UV-photoelectron emission microscopy, and transmission electron microscopy. The single-domain structure of the wire segments is evidenced by magnetic force microscopy.
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机译：提出了一种制备三维磁数据存储材料系统的方法。主要成分是惰性纳米多孔基质，它是通过对圆柱形孔内的线状磁性和非磁性金属进行阳极氧化和电镀而制备的。单个的纳米磁铁由镍钴合金组成，可通过将电解浴的组成调整到一个最佳施加电势来系统地调节其组成。用超导量子干涉仪磁力计定量得到的最低组成为Ni 60 Co 40 的磁晶各向异性。通过单线磁光Kerr效应磁力测定法确定，这种成分的导线会经历磁畴壁的无钉扎传播。在电解液中添加铜可以使Ni 60 Co 40 产生被非磁性铜隔开的链段。在通过扫描电子显微镜，UV-光电子发射显微镜和透射电子显微镜成像的单个纳米线中，片段结构是显而易见的。线段的单畴结构由磁力显微镜证实。
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