• DocumentCode
    847019
  • Title

    Yttrium iron garnet heterocoagulated by silica

  • Author

    Godoi, Ricardo H M ; Marques, Rodrigo F C ; Varanda, Laudemir C. ; Jafelicci, Miguel, Jr.

  • Author_Institution
    Antwerp Univ., Belgium
  • Volume
    38
  • Issue
    5
  • fYear
    2002
  • fDate
    9/1/2002 12:00:00 AM
  • Firstpage
    2625
  • Lastpage
    2627
  • Abstract
    Coated purpose of homogeneous distribution as a second phase is introduced in magnetic systems. Yttrium iron garnet (YIG) shows special interest as magnetic dye, microwave absorber, and magnetic fluids when heterocoagulated by other material. Surface and interface magnetic properties are intimately connected with the new properties of the silica on YIG system. Neel first introduced the concept of surface anisotropy, and Chen el al. developed a model that describes the anisotropy effects at the boundary surface particle, which was applied in this work. Spherical YIG particles were prepared by coprecipitation method and coated with silica using the tetraethylorthosilicate (TEOS) hydrolysis process. The silica-YIG boundary was investigated by transmission electron microscopy. Hysteresis loops comparatively show the profile of the naked and silica-covered YIG particles. The surface anisotropies were calculated using the Chen et al. approach. Indeed, in heterocoagulation systems, the surface anisotropy is a result of the interface symmetry breaking, as observed.
  • Keywords
    X-ray photoelectron spectra; coagulation; coercive force; garnets; magnetic anisotropy; magnetic hysteresis; magnetic particles; particle size; precipitation (physical chemistry); surface magnetism; transmission electron microscopy; yttrium compounds; X-ray photoemission; YFe5O12; YFe5O12-SiO2; YIG; YIG-SiO2; average particle size; coercive field; coprecipitation method; heterocoagulation by silica; homogeneous distribution; hysteresis loops; interface magnetic properties; interface symmetry breaking; magnetic dye; magnetic fluids; magnetic particles; microwave absorber; second phase; spherical particles; surface anisotropy; tetraethylorthosilicate hydrolysis; thin silica cover; transmission electron microscopy; Anisotropic magnetoresistance; Garnets; Iron; Magnetic anisotropy; Magnetic liquids; Magnetic materials; Magnetic properties; Perpendicular magnetic anisotropy; Silicon compounds; Yttrium;
  • fLanguage
    English
  • Journal_Title
    Magnetics, IEEE Transactions on
  • Publisher
    ieee
  • ISSN
    0018-9464
  • Type

    jour

  • DOI
    10.1109/TMAG.2002.801964
  • Filename
    1042292