Abstract
Electrodynamic theory applied to the analysis of TEn0p mode resonances in ferrimagnetic spheres placed either in metallic cavities or in the free space is compared with Walker-Fletcher's theory of so-called magnetostatic modes. The influence of the diameter of the sample, its permittivity and the permittivity of the surrounding media on the resonance frequencies of a few modes is analyzed. It is shown that the dominant resonances are essentially related either to negative values of the diagonal component of the permeability tensor or, for clockwise circularly polarized magnetic fields, to negative effective permeability. The electrodynamic theory is used to determine the saturation magnetization (Ms) from measured TEn01 frequency differences. Measurements on different samples confirmed that Ms can be determined using an electrodynamic approach with uncertainties of the order of 2% regardless of sample sizes or metal enclosures if the anisotropy field is negligible compared to the static internal magnetic bias.
| Original language | English |
|---|---|
| Article number | 165331 |
| Journal | Journal of Magnetism and Magnetic Materials |
| Volume | 487 |
| DOIs | |
| Publication status | Published - 1 Oct 2019 |
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Electrodynamic improvements to the theory of magnetostatic modes in ferrimagnetic spheres and their applications to saturation magnetization measurements. / Krupka, Jerzy; Pacewicz, Adam; Salski, Bartlomiej; Kopyt, Paweł; Bourhill, Jeremy; Goryachev, Maxim; Tobar, Michael.
In: Journal of Magnetism and Magnetic Materials, Vol. 487, 165331, 01.10.2019.Research output: Contribution to journal › Article
TY - JOUR
T1 - Electrodynamic improvements to the theory of magnetostatic modes in ferrimagnetic spheres and their applications to saturation magnetization measurements
AU - Krupka, Jerzy
AU - Pacewicz, Adam
AU - Salski, Bartlomiej
AU - Kopyt, Paweł
AU - Bourhill, Jeremy
AU - Goryachev, Maxim
AU - Tobar, Michael
PY - 2019/10/1
Y1 - 2019/10/1
N2 - Electrodynamic theory applied to the analysis of TEn0p mode resonances in ferrimagnetic spheres placed either in metallic cavities or in the free space is compared with Walker-Fletcher's theory of so-called magnetostatic modes. The influence of the diameter of the sample, its permittivity and the permittivity of the surrounding media on the resonance frequencies of a few modes is analyzed. It is shown that the dominant resonances are essentially related either to negative values of the diagonal component of the permeability tensor or, for clockwise circularly polarized magnetic fields, to negative effective permeability. The electrodynamic theory is used to determine the saturation magnetization (Ms) from measured TEn01 frequency differences. Measurements on different samples confirmed that Ms can be determined using an electrodynamic approach with uncertainties of the order of 2% regardless of sample sizes or metal enclosures if the anisotropy field is negligible compared to the static internal magnetic bias.
AB - Electrodynamic theory applied to the analysis of TEn0p mode resonances in ferrimagnetic spheres placed either in metallic cavities or in the free space is compared with Walker-Fletcher's theory of so-called magnetostatic modes. The influence of the diameter of the sample, its permittivity and the permittivity of the surrounding media on the resonance frequencies of a few modes is analyzed. It is shown that the dominant resonances are essentially related either to negative values of the diagonal component of the permeability tensor or, for clockwise circularly polarized magnetic fields, to negative effective permeability. The electrodynamic theory is used to determine the saturation magnetization (Ms) from measured TEn01 frequency differences. Measurements on different samples confirmed that Ms can be determined using an electrodynamic approach with uncertainties of the order of 2% regardless of sample sizes or metal enclosures if the anisotropy field is negligible compared to the static internal magnetic bias.
KW - Ferromagnetic resonance
KW - Magnetic plasmon
KW - Magnetostatic modes
KW - Saturation magnetization
KW - YIG sphere
UR - http://www.scopus.com/inward/record.url?scp=85066437938&partnerID=8YFLogxK
U2 - 10.1016/j.jmmm.2019.165331
DO - 10.1016/j.jmmm.2019.165331
M3 - Article
VL - 487
JO - Journal of Magnetism & Magnetic Materials
JF - Journal of Magnetism & Magnetic Materials
SN - 0304-8853
M1 - 165331
ER -