Speaker
Description
Magnetic Force Microscopy (MFM) is a versatile tool to map the stray field emanating from a sample surface with high spatial resolution and sensitivity, and in applied magnetic fields up to several Teslas.
The technical aspects of MFM will be reviewed and examples of high current interest such systems exhibiting interfacial Dzyaloshinskii-Moriya interaction (DMI) will be discussed. The average Dzyaloshinskii-Moriya (DM) interaction D, and the exchange stiffness A can be extracted from MFM data of the domain structure obtained after different demagnetization procedures. Local values of D, Ku, and A can be obtained from fitting model skyrmion magnetization structures to MFM data. We find that the local values of D are substantially larger than the average value, indicating that in our system, the skyrmions are strongly pinned. Apart from the domains and skyrmions MFM can also detect small field variations arising from a local variation of the areal magnetic moment density that can be attributed to a corresponding variation of the Co layer thickness. High-resolution and quantitative MFM is thus a powerful experimental method to assess local magnetic sample properties relevant for the development of future skyrmionic devices.
