Nanopatterning magnetic thin films by Ga ion irradiation

Local patterning in two film systems with different properties can be achieved using ion irradiation. The aim is to create a high density of domain walls at predetermined sites in a film. The strategy adopted is to write narrow lines by focused ion beam (FIB), such sites act as preferred sites for walls to locate. This is a direct consequence of structural modifications. The effect of the irradiation on the physical microstructure of the films are studied by high resolution and analytical electron microscopy whilst Lorentz microscopy is used to investigate the way the magnetic properties are modified.