Almeida, T. P. , Muxworthy, A. R., Kovács, A., Williams, W., Nagy, L., Conbhuí, P. Ó., Frandsen, C., Supakulopas, R. and Dunin-Borkowski, R. E. (2016) Direct observation of the thermal demagnetization of magnetic vortex structures in nonideal magnetite recorders. Geophysical Research Letters, 43(16), pp. 8426-8434. (doi: 10.1002/2016GL070074)
|
Text
123277.pdf - Published Version Available under License Creative Commons Attribution. 4MB |
Abstract
The thermal demagnetization of pseudo-single-domain (PSD) magnetite (Fe3O4) particles, which govern the magnetic signal in many igneous rocks, is examined using off-axis electron holography. Visualization of a vortex structure held by an individual Fe3O4 particle (~250 nm in diameter) during in situ heating is achieved through the construction and examination of magnetic-induction maps. Stepwise demagnetization of the remanence-induced Fe3O4 particle upon heating to above the Curie temperature, performed in a similar fashion to bulk thermal demagnetization measurements, revealed that its vortex state remains stable under heating close to its unblocking temperature and is recovered upon cooling with the same or reversed vorticity. Hence, the PSD Fe3O4 particle exhibits thermomagnetic behavior comparable to a single-domain carrier, and thus, vortex states are considered reliable magnetic recorders for paleomagnetic investigations.
| Item Type: | Articles (Letter) |
|---|---|
| Additional Information: | The work was funded by the UK Natural Environment Research Council (NERC grant NE/J020508/1) and the European Research Council (Advanced ERC grant 320832). |
| Status: | Published |
| Refereed: | Yes |
| Glasgow Author(s) Enlighten ID: | Almeida, Dr Trevor |
| Authors: | Almeida, T. P., Muxworthy, A. R., Kovács, A., Williams, W., Nagy, L., Conbhuí, P. Ó., Frandsen, C., Supakulopas, R., and Dunin-Borkowski, R. E. |
| Subjects: | Q Science > QC Physics Q Science > QE Geology |
| College/School: | College of Science and Engineering > School of Physics and Astronomy |
| Research Group: | Materials and Condensed Matter Physics Group |
| Journal Name: | Geophysical Research Letters |
| Publisher: | Wiley |
| ISSN: | 0094-8276 |
| ISSN (Online): | 1944-8007 |
| Published Online: | 30 July 2016 |
| Copyright Holders: | Copyright © 2016 The Authors |
| First Published: | First published in Geophysical Research Letters 43(16):8426-8434 |
| Publisher Policy: | Reproduced under a Creative Commons License |
University Staff: Request a correction | Enlighten Editors: Update this record
Deposit and Record Details
Deposit and Record Details