Atkinson, Lewis J., Evans, Richard F.L. orcid.org/0000-0002-2378-8203 and Chantrell, Roy W. orcid.org/0000-0001-5410-5615 (2020) Micromagnetic modeling of the heat-assisted switching process in high anisotropy FePt granular thin films. Journal of Applied Physics. 073907. ISSN 1089-7550
Abstract
The dynamic process of assisted magnetic switchings has been simulated to investigate the associated physics. The model uses a Voronoi construction to determine the physical structure of the nanogranular thin film recording media, the Landau-Lifshitz-Bloch equation is solved to evolve the magnetic system in time. The reduction of the magnetization is determined over a range of peak system temperatures and for a number of anisotropy values. The results show that the heat-assisted magnetic recording process is not simply magnetization reversal over a thermally reduced energy barrier. To achieve full magnetization reversal (for all anisotropies investigated), an applied field strength of at least 6 kOe is required and the peak system temperature must reach at least the Curie point (T c). When heated to T c, the magnetization associated with each grain is destroyed, which invokes the non-precessional linear reversal mode. Reversing the magnetization through this linear reversal mode is favorable, as the reversal time is two orders of magnitude smaller than that associated with precession. Under these conditions, as the temperature decreases to ambient, the magnetization recovers in the direction of the applied field, completing the reversal process. Also, the model produces results that are consistent with the concept of thermal writability; when heating the media to T c, the smaller grains require a larger field strength to reverse the magnetization.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2020 Author(s). Published under license by AIP Publishing. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details. |
Dates: |
|
Institution: | The University of York |
Academic Units: | The University of York > York Institute for Materials Research The University of York > Faculty of Sciences (York) > Physics (York) |
Depositing User: | Pure (York) |
Date Deposited: | 30 Oct 2020 12:40 |
Last Modified: | 16 Dec 2024 00:14 |
Published Version: | https://doi.org/10.1063/1.5143120 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1063/1.5143120 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:167420 |