Advanced Fabrication and Characterization of Magnetic Nanowires

Abstract

Magnetic nanowires feature unique properties that have attracted the interest of different research areas from basic physics over biomedicine to data storage. The combination of crystalline and shape anisotropy is mainly responsible for the magnetic properties of the nanowires, whereby different methods for tuning those properties are available. The nanowires typically represent single-domain particles, and magnetization switching occurs via domain walls nucleated at the ends of the nanowire and traversing it. Combined with a high biocompatibility, iron or iron oxide nanowires can be used as nanorobots for biomedical applications, destroying cancer cells, or delivering drugs. The nanowires are also attractive for data storage, especially in a three-dimensional device, because of the high-domain wall speed that has been theoretically predicted. This chapter offers an introduction to the electrochemical synthesis of cylindrical nanowires in anodic aluminum oxide (AAO) templates. Template modification techniques such as barrier layer thinning, barrier layer etching, and diameter modulation are discussed. Advanced fabrication techniques of nanowires with varying structural and chemical variations such as multisegmented and core-shell nanowires are elaborated. The characterization of single nanowires encompassing physical, magnetic, and electrical techniques is covered