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The preparation of vertically or horizontally aligned self-assemblies of CoP nanowires is demonstrated for the first time by aging them in the reaction solution for a sufficient time at 20 or 0 °C. This strategy opens up a way for exploring the controlled self-assembly of various highly anisotropic nanostructures into long-range ordered structures with collective properties., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Cobalt films were grown by molecular beam epitaxy on CaF2 buffer layers on silicon. Due to unique properties of CaF2/Si(100) interface, the surface of CaF2 has grooves along [110] direction. Cobalt grown on it has in-plane uniaxial magnetic anisotropy with easy axis along the grooves. The dependence of remanence magnetisation and coercivity on azimuth angle (between the grooves and field) follows single domain model in the range from 0 to 80 degrees. For hysteresis loops of both parallel and perpendicular components of magnetisation, quantitative agreement was achieved within the model of coherent rotation with certain distribution of anisotropy energy over regions of the sample. Between 80 degrees and 90 degrees, the film splits into multiple domains.

Graphitically encapsulated cobalt nanocrystal assemblies are chemically prepared by one-pot reaction at >380 degrees C followed by a reversed etching process to produce porous graphitic structure for revealing their self-assembling nature.

Oxidation-induced constituent separation of ternary Fe/CoO nanocrystals has been investigated to evidence their exchange bias mechanism, which is important for conceptually new design, synthesis and utilization of magnetic nanostructures.