The dynamics of magnetic vortices in thin Permalloy disks having artificial defects in the form of small holes at different locations within the disk has been investigated by means of frequency-domain spatially resolved ferromagnetic resonance. It is found that the vortex can be effectively captured by such a defect. Consequently the commonly observed gyrotropic vortex motion in an applied microwave field of 1 mT is suppressed. However, if in addition a static magnetic field of at least 4.3 mT is applied, the vortex core is nucleated from the artificial defect and a modified gyrotropic motion starts again.

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A focused ion beam (FIB) has been applied to the fabrication of polymer microtubes via the rolling-up technique from poly(4-vinyl pyridine)/polystyrene bilayer films deposited on the top of a sacrificial aluminum layer covering a silicon wafer. The bending forces in the film arise due to different swelling of the bilayer components in acidic water and lead to rolling of the film. The dimensions and position of the rolled-up tubes can be controlled by FIB milling (sputtering) of geometrically well-adjusted openings in the polymer films. This technique can be applied to the structuring of scrolled films formed from different materials without the use of lithographically patterned photoresists. The geometrical patterning of the tube interior can also be done by FIB irradiation.

Cobalt implantation with a focused ion beam ͑FIB͒ was applied to study ion beam synthesis of cobalt disilicide nanowires in silicon. Two mechanisms of CoSi 2 nanowire formation were investigated: ͑a͒ conventional synthesis by Co ++ FIB implantation at elevated temperatures into silicon along in-plane ͗110͘ Si crystal direction and subsequent annealing and ͑b͒ self-aligned CoSi 2 nanowire growth in cobalt supersaturated silicon on FIB-induced defects at room temperature during subsequent annealing. The obtained CoSi 2 nanowires are 20-100 nm in diameter and several micrometers long.

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