Abstract
We have carried out studies of the magnetic reversal process of a rare earth-transition metal thin film with perpendicular magnetic anisotropy using a magnetic force microscope (MFM) capable of applying in situ magnetic fields. The magnetization of the microscopic area shown in MFM images was determined for a number of field values comprising a complete hysteresis loop. This microscopic hysteresis loop was found to be nearly identical to a bulk hysteresis loop. Changes in the magnetization of the film as the hysteresis loop was traversed can be linked to individual microscopic domain changes evident in the MFM images. These studies show that the magnetization of this film was characterized by a two-stage process - fast and slow rates of change of magnetization with applied field. A second experiment in which the film was incompletely saturated and brought back to zero field showed that domain nucleation was not responsible for the rate of the fast process, but rather all magnetization changes were primarily limited by the low domain wall mobility. These observations are linked to previous work on magnetization processes in similar magnetic systems.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 81-88 |
| Number of pages | 8 |
| Journal | Journal of Magnetism and Magnetic Materials |
| Volume | 190 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - Dec 1 1998 |
Bibliographical note
Funding Information:The authors thank William Challener of Imation Corporation for preparation of the thin film samples studied and Matt Dugas for the coated tips used in this work. This work was supported by Imation Corporation and grants #N00014-94-1-0123 and #N00014-95-1-0799 from the Office of Naval Research. One of the authors (J.S.) would like to thank the University of Minnesota Graduate School for financial support.
Keywords
- Domain wall motion
- Magnetic reversal
- Thin films