Controlling multidomain states to enable sub-10-nm magnetic force microscopy

Abstract

The letter reports experimental data to demonstrate magnetic force microscopy (MFM) with sub-10-nm resolution under ambient conditions. To achieve this record high resolution, multidomain states in a nanomagnetic probe were controlled. Two demagnetized (multidomain) FePt (45/55) films sputtered on a silicon probe and separated by an 8 nm thick MgO layer were further annealed at temperature of 650 °C to trigger the high-anisotropy L10 phase. A field of above 2 T was applied to drive the probes into a saturated “single-domain” state. The multidomain probes were equivalently compared with state-of-the-art conventional MFM probes via comparative imaging of benchmark magnetic recording disks.