High resolution magnetic field energy imaging of the magnetic recording head by A-MFM with Co-GdOx super-paramagnetic tip

Abstract

In this letter, the concept of a high-resolution magnetic field energy imaging technique is demonstrated by a high susceptibility superparamagnetic Co-GdOx magnetic force microscopy (MFM) tip for a perpendicular magnetic recording head with alternating magnetic force microscopy (A-MFM). The distribution of the magnetic energy gradient from the perpendicular recording head is imaged by the Co-GdOx superparamagnetic tip and compared with magnetic field imaging by the FePt-MgO hard magnetic tip. The Fourier analysis of the A-MFM amplitude images revealed enhancement in a spatial resolution of 13 nm by the Co-GdOx superparamagnetic tip as compared to 17 nm by the state-of-the-art FePt-MgO hard magnetic tip. The magnetic dipolar nature and short range force character of magnetic energy imaging by the Co-GdOx superparamagnetic tip showed high performance, confirmed by the tip transfer function analysis as compared to the monopole type FePt-MgO hard magnetic tip. The proposed technique opens an opportunity for the development of advanced high-resolution magnetic energy based imaging methods and development of the high-resolution MFM tips.