1. Low-loss barium ferrite quasi-single-crystals for microwave application
- Author
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Vincent G. Harris, Taiyang Chen, Tomokazu Sakai, Anton L. Geiler, Carmine Vittoria, and Yajie Chen
- Subjects
Materials science ,Condensed matter physics ,Beta ferrite ,General Physics and Astronomy ,Coercivity ,Ferromagnetic resonance ,chemistry.chemical_compound ,Nuclear magnetic resonance ,chemistry ,Ferrite (magnet) ,Crystallite ,Single crystal ,Barium ferrite ,Seed crystal - Abstract
Barium hexaferrites (BaFe12O19) are especially useful for microwave/millimeter devices. Due to large ferromagnetic resonance (FMR) loss (linewidths >2kOe), traditional compacts of polycrystalline Ba ferrites indeed hinder the utilization of the materials for practical devices. The present experiment demonstrates that the quasi-single-crystal Ba ferrite disks can be fabricated by a single solid-state reaction technique without liquid phase participation, combining with a processing of alignment for the ferrite seed crystals. The ferrite bulks show a pure hexagonal Ba ferrite phase, an expected 4πMs of 4.48kG, and coercivity of 10∼20Oe along the c axis, similar to the results of a typical single crystal. The FMR measurement indicates that the sample yields an anisotropy field of 16.0kOe and a linewidth of about 300Oe at U-band frequencies. Although the linewidth is broader than ideal Ba ferrite single crystals (ΔH
- Published
- 2007
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