High resolution magnetic force microscopy

Abstract

The lateral resolution observed in recent MFM experiments on CoCr and FeNdB are compared and analyzed theoretically. On a Co80Cr20 thin film a stripe domain structure with a domain width of 220 nm is observed, the highest resolution of a periodic magnetic structure measured by MFM to this date, and magnetic fine structure of typically 50 nm width and more than 200 nm length by measuring magnetic forces as small as 0.1 nN. A resolution of 10 nm is obtained on rapidly quenched FeNdB, where domains with a typical size of 600–700 nm are observable. By comparing these measurements with simulations it is concluded that the lower resolution achieved on CoCr is to be expected as the domain size is similar to the typical spatial extent of the domain transition stray field.