The bottom-up approach in nanofabrication involves the synthesis of functional nanoscale building blocks and controllable assembly into larger scale superstructures. Electrochemical template synthesis has been employed in this work to fabricate two kinds of nanoscale building blocks: (1) Ni/Cu multilayer nanowires, and (2) Au/Pt/Au and Au/Ni/Au multi-segment nanowires.; Magnetic nanowires exhibit unique physical properties and have potential applications in spintronics devices as well as in biomagnetic application. In magnetic multilayer nanowires, the orientation of the easy axis, the coercivity, remanence, demagnetization factor and many other magnetic parameters can be tuned by varying the size, shape and spacing of magnetic layers and nonmagnetic layers.; Ni/Cu multilayer nanowires were fabricated using single bath techniques in polycarbonate templates with diameters in the range of 40-140 nm. The composition and structure of the nanowires was studied using x-ray diffraction, auger electron spectroscopy and transmission electron microscopy. The magnetic properties of nanowires depend on the diameter and aspect ratio of the nickel layers and the spacing of nickel layers. Micromagnetic simulations were used to model the M-H loops. The different magnetic alignment of nanowires in suspension was demonstrated.; Multicomponent nanowires allow the possibility of attaching different functional groups to different segments thereby providing spatially localized functionality. This feature is particularly attractive for self-assembly since receptor groups can be attached at specific locations on the particle where attachment will occur. Directed assembly using receptor mediated interactions provides a powerful tool for the self-assembly of complex architectures. The kinetic of receptor-mediated end-to-end assembly can be explained by diffusion-limited aggregation process analogues to linear polycondensation theory.
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