Abstract
Bit-patterned media at one terabit-per-square-inch (Tb/in2) recording density require a feature size of about 12 nm. The fabrication and characterization of such magnetic nanostructures is still a challenge. In this Letter, we show that magnetic dots can be resolved at 10 nm spacing using magnetic force microscopy (MFM) tips coated with a magnetic film possessing a perpendicular magnetic anisotropy (PMA). Compared to MFM tips with no special magnetic anisotropy, MFM tips with PMA can resolve the bits clearly, because of a smaller magnetic interaction volume, enabling a simple technique for characterizing fine magnetic nanostructures. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)