Microwave impedance control over a ferrite boundary layer

• Published in: IEEE transactions on magnetics Vol. 41; no. 3; pp. 1126 - 1131
• Main Authors: How, H., Vittoria, C.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.03.2005; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Bias; Coaxial cables; Coils; Cross-disciplinary physics: materials science; rheology; DC generators; Exact sciences and technology; Ferrimagnetic materials; Ferrite; Ferrite device; Ferrites; Ground plane; Impedance; impedance control; Magnetic fields; Magnetic permeability; Magnetic resonance; Magnetism; Materials science; Microwaves; Other topics in materials science; Permanent magnets; Permeability; Physics; reflection measurement; reflection measurement; Ferrite; Magnetic permeability; impedance control; Impedance; Magnetic properties; Ferrite device
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2004.843339

We simulated microwave far-field radiation by using a coaxial cable, inside which a ferrite layer with a ground plane was loaded. The ferrite layer is magnetically biased near ferrimagnetic resonance by a permanent magnet generating a global bias magnetic field inside the ferrite layer. In addition, a magnetic bias coil near the ferrite layer generates a second dc bias magnetic field so as to locally tune the permeability of the ferrite layer. By observing the frequency change in the resonant modes of the cavity formed by the coaxial cable, we can determine the permeability of the ferrite layer. Calculations compare nicely with experiments.