Magnetic and microwave properties of U-type hexaferrite films with high remanence and low ferromagnetic resonance linewidth

Journal Article · Wed May 07 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4854935· OSTI ID:22273925

Su, Zhijuan; Bennett, Steven; Hu, Bolin; Chen, Yajie; Harris, Vincent G. ^[1]

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1. Center for Microwave Magnetic Materials and Integrated Circuits, Northeastern University, Boston, Massachusetts 02115, USA and The Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States)

U-type barium hexaferrite films (Ba{sub 4}Ni{sub 1.4}Co{sub 0.6}Fe{sub 36}O{sub 60}) were deposited on (0001) sapphire substrates by pulsed laser deposition. Microstructure and magnetic properties of the films were characterized by X-ray diffraction, scanning electron microscopy and vibrating sample magnetometry. Ferromagnetic resonance (FMR) measurements were performed at X-band. The results indicate an anisotropy field of ∼8 kOe, and the saturation magnetization (4πM{sub s}) of ∼3.6 kG. An optimal post-deposition annealing of films results in a strong (0 0 n) crystallographic texture and a high hysteresis loop squareness (M{sub r}/M{sub s} = 92%) leading to self biased properties. Furthermore, the highly self-biased ferrite films exhibited an FMR linewidth of ∼200 Oe. The U-type hexaferrite films having low microwave loss, low magnetic anisotropy field, and high squareness are a suitable alternative to Sc or In doped BaM ferrites that have been the choice material for self-biased microwave devices at X-band frequencies.

• OSTI ID: 22273925
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 17; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANISOTROPY
BARIUM COMPOUNDS
COBALT COMPOUNDS
CRYSTAL STRUCTURE
DOPED MATERIALS
ENERGY BEAM DEPOSITION
FERRITES
FERROMAGNETIC RESONANCE
HYSTERESIS
LASER RADIATION
MAGNETIC PROPERTIES
MAGNETIZATION
MICROSTRUCTURE
MICROWAVE RADIATION
NICKEL COMPOUNDS
PULSED IRRADIATION
SAPPHIRE
SCANNING ELECTRON MICROSCOPY
THIN FILMS
X-RAY DIFFRACTION