Iron nanowire arrays have been grown by shadow deposition on a self-organized grating template produced by annealing the sodium chloride (110) surface. The typical wire size as measured using transmission electron microscopy is 45 nm×13 nm×10 μm. The typical wire array period is 90 nm. The magnetic properties were dominated by a strong in-plane shape anisotropy. The hysteresis loops examined by magneto-optical Kerr effect measurements indicated coherent switching, even though the individual wires were isolated from one another.

Quasi-one-dimensional, nanometer-diameter Fe particle arrays have been prepared by self-organized shadow growth on regularly faceted NaCl (110) surfaces. A room-temperature dipole-ferromagnetic phase was observed for linear arrays of Fe particles with radii larger than 2.5 nm. Surface magneto-optic Kerr magnetization curves indicate easy-axis alignment along the rows of particles. Remanence and coercivity were strong functions of particle diameter and linear island density. Experimental results are compared with Monte Carlo micromagnetics calculations, which, with no free parameters, reproduce the experimental observations.

Three types of mesoscopic magnetic microstructure have been formed using self-organization: linear arrays of nanometer diameter islands, nanometer width lines, and undulating, continuous films. These structures were produced by annealing NaCl (110) and (111) surfaces in situ to produce patterned templates with 10–100 nm periodicity. Growth parameters such as groove spacing, substrate temperature and total deposit thickness can be varied in order to define specific mesoscopic magnetic structures. The microstructural evolution during growth is discussed in the context of nucleation and coalescence kinetics. The resulting magnetic properties are described, and their connection to the underlying microstructure elucidated.

Nanometre-scale magnetic field distributions in materials such as those at oxide interfaces, in thin layers of spintronics devices, and at boundaries in magnets have become important research targets in materials science and applied physics. Electron holography has advantages in nanometric magnetic field observations, and the realization of aberration correctors has improved its spatial resolution. Here we show the subnanometre magnetic field observations inside a sample at 0.67-nm resolution achieved by an aberration-corrected 1.2-MV holography electron microscope with a pulse magnetization system. A magnetization reduction due to intermixing in a CoFeB/Ta multilayer is analyzed by observing magnetic field and electrostatic potential distributions simultaneously. Our results demonstrate that high-voltage electron holography can be widely applied to pin-point magnetization analysis with structural and composition information in physics, chemistry, and materials science.