The University of Southampton
University of Southampton Institutional Repository

Modeling the magnetic properties of DyFe2/YFe2 superlattices

Modeling the magnetic properties of DyFe2/YFe2 superlattices
Modeling the magnetic properties of DyFe2/YFe2 superlattices
The Stoner–Wohlfarth model has proved reasonably successful in describing the coercivities of antiferromagnetically coupled DyFe2/YFe2 hard/soft superlattices in the absence of magnetic exchange springs. In particular, the coercivity rises sharply as the net magnetic moment of the superlattice approaches zero. However the situation becomes more complicated as the thickness of the YFe2 layers is increased. Two distinct "instability fields" can be identified: the bending field BB, signifying the onset of a magnetic exchange spring, and the irreversible switching field BIS associated with magnetic reversal. We have developed a computational model to address this problem. In particular, it is shown that the two instability fields in question are characterized by vanishing eigenvalues in the matrix formed by the double energy derivatives [partial-derivative]2E/[partial-derivative]thetai[partial-derivative]thetaj, where E is the total energy and thetai the angle of each individual monolayer. It is shown that the model provides a very good description of the M–Bapp loops of DyFe2/YFe2 multilayer films. In particular, the coercivity of a nearly magnetically compensated multilayer (75 ÅDyFe2/150 ÅYFe2) is much reduced below the prediction of the Stoner–Wolhfarth model, in accord with experiment.
0021-8979
6480-6482
Bowden, G.J.
f73a1c01-4d38-4170-bf30-9ebfa4283807
Beaujour, J-M.L.
5cb1e799-4872-4fe1-b240-58e0a4d92c8e
Zhukov, A.A.
75d64070-ea67-4984-ae75-4d5798cd3c61
Rainford, B.D.
a57f1153-bbba-49a3-bffc-0d96087156a0
de Groot, P.A.J.
98c21141-cf90-4e5c-8f2b-d2aae8efb84d
Ward, R.C.C.
b5eaa153-e136-4555-8b07-325a4b5329cb
Wells, M.R.
eb14a225-4803-4e6c-87b6-c1d1e5b8483d
Bowden, G.J.
f73a1c01-4d38-4170-bf30-9ebfa4283807
Beaujour, J-M.L.
5cb1e799-4872-4fe1-b240-58e0a4d92c8e
Zhukov, A.A.
75d64070-ea67-4984-ae75-4d5798cd3c61
Rainford, B.D.
a57f1153-bbba-49a3-bffc-0d96087156a0
de Groot, P.A.J.
98c21141-cf90-4e5c-8f2b-d2aae8efb84d
Ward, R.C.C.
b5eaa153-e136-4555-8b07-325a4b5329cb
Wells, M.R.
eb14a225-4803-4e6c-87b6-c1d1e5b8483d

Bowden, G.J., Beaujour, J-M.L., Zhukov, A.A., Rainford, B.D., de Groot, P.A.J., Ward, R.C.C. and Wells, M.R. (2003) Modeling the magnetic properties of DyFe2/YFe2 superlattices. Journal of Applied Physics, 93 (10), 6480-6482. (doi:10.1063/1.1539072).

Record type: Article

Abstract

The Stoner–Wohlfarth model has proved reasonably successful in describing the coercivities of antiferromagnetically coupled DyFe2/YFe2 hard/soft superlattices in the absence of magnetic exchange springs. In particular, the coercivity rises sharply as the net magnetic moment of the superlattice approaches zero. However the situation becomes more complicated as the thickness of the YFe2 layers is increased. Two distinct "instability fields" can be identified: the bending field BB, signifying the onset of a magnetic exchange spring, and the irreversible switching field BIS associated with magnetic reversal. We have developed a computational model to address this problem. In particular, it is shown that the two instability fields in question are characterized by vanishing eigenvalues in the matrix formed by the double energy derivatives [partial-derivative]2E/[partial-derivative]thetai[partial-derivative]thetaj, where E is the total energy and thetai the angle of each individual monolayer. It is shown that the model provides a very good description of the M–Bapp loops of DyFe2/YFe2 multilayer films. In particular, the coercivity of a nearly magnetically compensated multilayer (75 ÅDyFe2/150 ÅYFe2) is much reduced below the prediction of the Stoner–Wolhfarth model, in accord with experiment.

This record has no associated files available for download.

More information

Published date: 2003

Identifiers

Local EPrints ID: 57106
URI: http://eprints.soton.ac.uk/id/eprint/57106
ISSN: 0021-8979
PURE UUID: c02893f8-cb77-477e-bb4f-e6e6b1abc9c1

Catalogue record

Date deposited: 13 Aug 2008
Last modified: 15 Mar 2024 11:05

Export record

Altmetrics

Contributors

Author: G.J. Bowden
Author: J-M.L. Beaujour
Author: A.A. Zhukov
Author: B.D. Rainford
Author: P.A.J. de Groot
Author: R.C.C. Ward
Author: M.R. Wells

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×