Magnetic and Dielectric Excitations in the W-Band in Aluminum Substituted Barium and Strontium Hexaferrites

Author

Popov, Maksym A. ; Zavislyak, Igor V. ; Tatarenko, Alexander S. ; Srinivasan, Gopalan ; Balbashov, A.M.

Author_Institution

Phys. Dept., Oakland Univ., Rochester, MI

Volume

45

Issue

5

fYear

2009

fDate

5/1/2009 12:00:00 AM

Firstpage

2053

Lastpage

2058

Abstract

Single crystal strontium and barium hexaferrites in which Al is substituted for Fe have uniaxial anisotropy fields on the order of 20-30 kOe and have magnetic excitations at 75-110 GHz. Here, we discuss results of investigations on magnetostatic forward volume waves and dielectric resonances in such ferrites. Data on the mode frequencies were utilized to characterize the ferrites in terms of saturation magnetization, anisotropy field, gyromagnetic ratio, dielectric permittivity, and dielectric and magnetic losses. A refined theory of magnetostatic forward volume waves with explicit characteristic equation for the dominant mode is presented. The estimates on the mode characteristics are in very good agreement with the data.

Keywords

aluminium compounds; barium compounds; dielectric losses; dielectric resonance; eddy current losses; ferromagnetic materials; ferromagnetic resonance; gyromagnetic ratio; magnetic anisotropy; magnetic leakage; permittivity; strontium compounds; BaAl_xFe_12-xO₁₉; SrAl_xFe_12-xO₁₉; W-band; aluminum substituted barium hexaferrites; dielectric losses; dielectric permittivity; dielectric resonances; ferromagnetic resonance; frequency 75 GHz to 110 GHz; gyromagnetic ratio; magnetic anisotropy field; magnetic excitations; magnetic losses; magnetostatic forward volume waves; saturation magnetization; single crystal strontium hexaferrites; uniaxial anisotropy; Dielectric resonators; ferrites; magnetic resonance; millimeter wave measurements;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2008.2008414

Filename

4815992