Biased magnetic materials in RAM applications
Ramprecht, Jörgen and Sjöberg, Daniel LU
(2007)
In Technical Report LUTEDX/(TEAT-7155)/1-29/(2007)
- Abstract
- The magnetization of a ferro- or ferri-magnetic material has been
modeled with the Landau-Lifshitz-Gilbert (LLG) equation. In this
model demagnetization effects are included. By applying a linearized
small signal model of the LLG equation, it was found that the
material can be described by an effective permeability and with the
aid of a static external biasing field, the material can be switched
between a Lorentz-like material and a material that exhibits a
magnetic conductivity. Furthermore, the reflection coefficient for
normally impinging waves on a PEC covered with a
ferro/ferri-magnetic material, biased in the normal direction, is
... (More) - The magnetization of a ferro- or ferri-magnetic material has been
modeled with the Landau-Lifshitz-Gilbert (LLG) equation. In this
model demagnetization effects are included. By applying a linearized
small signal model of the LLG equation, it was found that the
material can be described by an effective permeability and with the
aid of a static external biasing field, the material can be switched
between a Lorentz-like material and a material that exhibits a
magnetic conductivity. Furthermore, the reflection coefficient for
normally impinging waves on a PEC covered with a
ferro/ferri-magnetic material, biased in the normal direction, is
calculated. When the material is switched into the resonance mode,
we found that there will be two distinct resonance frequencies in
the reflection coefficient, one associated with the precession
frequency of the magnetization and one associated with the thickness
of the layer. The former of these resonance frequencies can be
controlled by the bias field and for a bias field strength close to
the saturation magnetization, where the material starts to exhibit a
magnetic conductivity, one can achieve low reflection (around -20
dB) for a quite large bandwidth (more than two decades). (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1788117
- author
- Ramprecht, Jörgen
and Sjöberg, Daniel
LU
- organization
- publishing date
- 2007
- type
- Book/Report
- publication status
- published
- subject
- in
- Technical Report LUTEDX/(TEAT-7155)/1-29/(2007)
- pages
- 29 pages
- publisher
- [Publisher information missing]
- report number
- TEAT-7155
- external identifiers
-
- scopus:34547246315
- language
- English
- LU publication?
- yes
- additional info
- Published version: Progress In Electromagnetics Research, Vol. 75, pp. 85-117, 2007.
- id
- 2b66608f-1e0d-4aaf-9fab-0955d8477c35 (old id 1788117)
- date added to LUP
- 2016-04-04 13:55:09
- date last changed
- 2022-07-25 05:24:44
@techreport{2b66608f-1e0d-4aaf-9fab-0955d8477c35,
abstract = {{The magnetization of a ferro- or ferri-magnetic material has been<br/><br>
modeled with the Landau-Lifshitz-Gilbert (LLG) equation. In this<br/><br>
model demagnetization effects are included. By applying a linearized<br/><br>
small signal model of the LLG equation, it was found that the<br/><br>
material can be described by an effective permeability and with the<br/><br>
aid of a static external biasing field, the material can be switched<br/><br>
between a Lorentz-like material and a material that exhibits a<br/><br>
magnetic conductivity. Furthermore, the reflection coefficient for<br/><br>
normally impinging waves on a PEC covered with a<br/><br>
ferro/ferri-magnetic material, biased in the normal direction, is<br/><br>
calculated. When the material is switched into the resonance mode,<br/><br>
we found that there will be two distinct resonance frequencies in<br/><br>
the reflection coefficient, one associated with the precession<br/><br>
frequency of the magnetization and one associated with the thickness<br/><br>
of the layer. The former of these resonance frequencies can be<br/><br>
controlled by the bias field and for a bias field strength close to<br/><br>
the saturation magnetization, where the material starts to exhibit a<br/><br>
magnetic conductivity, one can achieve low reflection (around -20<br/><br>
dB) for a quite large bandwidth (more than two decades).}},
author = {{Ramprecht, Jörgen and Sjöberg, Daniel}},
institution = {{[Publisher information missing]}},
language = {{eng}},
number = {{TEAT-7155}},
series = {{Technical Report LUTEDX/(TEAT-7155)/1-29/(2007)}},
title = {{Biased magnetic materials in RAM applications}},
url = {{https://lup.lub.lu.se/search/files/6236425/1788122.pdf}},
year = {{2007}},
}