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arXiv · 1111.5453

Magnetic and structural characterization of nanosized BaCo_xZn_{2-x}Fe_{16}O_{27} hexaferrite in the vicinity of spin reorientation transition

Alexander Pasko·Frédéric Mazaleyrat·Martino Lo Bue·Vincent Loyau·Vittorio Basso·Michaela Küpferling·Carlo Sasso·Lotfi Bessais
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Abstract

Numerous applications of hexagonal ferrites are related to their easy axis or easy plane magnetocrystalline anisotropy configurations. Certain W-type ferrites undergo spin reorientation transitions (SRT) between different anisotropy states on magnetic field or temperature variation. The transition point can be tuned by modifying the chemical composition, which suggests a potential application of hexaferrites in room temperature magnetic refrigeration. Here we present the results of structural and magnetic characterization of BaCo_xZn_{2-x}Fe_{16}O_{27} (0.7 \leq x \leq 2) doped barium ferrites. Fine powders were prepared using a sol-gel citrate precursor method. Crystal structures and particle size distributions were examined by X-ray diffraction and transmission electron microscopy. The optimal synthesis temperature ensuring complete formation of single W-phase with limited grain growth has been determined. Spin reorientation transitions were revealed by thermomagnetic analysis and AC susceptibility measurements.

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Alexander Pasko, Frédéric Mazaleyrat, Martino Lo Bue, Vincent Loyau, Vittorio Basso, Michaela Küpferling, Carlo Sasso, Lotfi Bessais. 2011-11-23. Magnetic and structural characterization of nanosized BaCo_xZn_{2-x}Fe_{16}O_{27} hexaferrite in the vicinity of spin reorientation transition. https://doi.org/10.1088/1742-6596%2F303%2F1%2F012045

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