Novel 'writing' using magnetic force microscopy in ultrahigh vacuum

Circular magnetic domains have been nucleated on ultrathin Co films by controlled surface touching using magnetic force microscopy tip in ultrahigh vacuum. The process of domain nucleation is due to strain induced perpendicular anisotropy on the surface of Co film. The smallest nucleated domain is 64 nm in diameter. The dependence of the size of the "written" domain on the time period of tip-sample contact has been measured.