Small magnetic patterns written with a scanning tunneling microscope

The authors present a technique for writing submicron magnetic bit patterns on double-layered perpendicular recording media by using a scanning tunneling microscope (STM) with an amorphous magnetic tip and observing them with a magnetic force microscope (MFM). The proposed technique provides a very small tip-to-medium spacing on the order of angstroms. It is shown that the magnetization of the extremity of an amorphous tip can be reversed by switching the external field. The possibility of writing magnetic bit patterns in double-layered perpendicular media at a high areal density equivalent to 1 Gb/in² or more by means of this technology is demonstrated