Magnetism of nanostructured materials for advanced magnetic recording

Abstract

Abstract The continuous increase in magnetic recording density has so far been achieved by scaling the geometrical dimensions. However, it is now obvious that conventional magnetic recording is reaching its scaling limit. To realize ultrahigh recording densities of 1 Tbit/in2 and beyond in the future one of the most straightforward concepts is bit-patterned composite media with a regular arrangement of magnetic nanodots, where each nanodot is composed of a hard magnetic and a soft magnetic part and represents one bit. The hard magnetic component guarantees thermal stability for smallest dot sizes whereas the soft magnetic component reduces the coercivity and thus enables writeability with conventional heads. In this review the requirements for ultrahigh density magnetic recording are presented which seem to be optimally fulfilled by L10-FePt (hard magnetic)/Fe (soft magnetic) nanocomposites.