Effect of Cation Vacancies on the Magnetic Annealing of Cobalt-Substituted Magnetite

Abstract

Articles you may be interested inEffect of annealing on the magnetic tunnel junction with Co/Pt perpendicular anisotropy ferromagnetic multilayers J. Appl. Phys. 107, 09C711 (2010); 10.1063/1.3358249 Influence of cobalt and nickel substitutions on populations, hyperfine fields, and hysteresis phenomenon in magnetite Effect of annealing on the structure and magnetic properties of graphite encapsulated nickel and cobalt nanocrystals

Ferrimagnetism

“…It has been found that relatively small amounts of certain metal impurities can quite seriously affect some properties : thus, for example, 1% cobalt in ferrous ferrite reduces the magnetocrystalline anisotropy by an order of magnitude at room temperature (Bickford, Brownlow and Penoyer 1957), while at very low temperatures even smaller amounts of impurities can have a large effect (see $ 3 5.4 and 5.7). Of course once the importance of these factors is recognized it is possible to take special precautions against certain impurities, but it is clear that very careful chemical techniques may be involved.…”

Development of magneto-dielectric materials based on Li-ferrite ceramics

“…It is well known that a small quantity of cobalt substitution can be used to improve the microwave properties of ferrite materials [3][4][5]. Co ions contribute larger positive magnetocrystalline anisotropy, while the magnetocrystalline anisotropy of most spinel ferrites is negative with a relatively smaller value.…”

Nanoscale Magnetization Reversal Caused by Electric Field-Induced Ion Migration and Redistribution in Cobalt Ferrite Thin Films

“…The B-site Co 2+ ion pairs and Fe 3+ ion pairs are arranged alternatively along the ⟨110⟩ directions, and Co 2+ ions are responsible for the magnetic anisotropy of the material . The cations also have the tendency to migrate through cation vacancies, which can be driven by annealing under magnetic field to induce the appearance of uniaxial magnetic anisotropy. − Comparatively, it is expected that the external electric fields may also provide the driving force for nanoscale ion migration − and consequently modulate the magnetization of CoFe 2 O 4 thin films with cationic vacancies.…”