Crystallographic structures and magnetic properties of chemically synthesized FePt nanoparticles, which were firmly stabilized into a monolayer on thermally oxidized Si substrate using 3-amino propyldimethylethoxysilene, were studied. The two-dimensional structure of FePt nanoparticles was confirmed by plan-view high-resolution scanning microscopy observation. The particles transformed from fcc to highly ordered L10 structure by annealing at 800°C under high vacuum with minimal coalescence. From rotational hysteresis loss analysis, a large magnetic anisotropy field of over 80kOe for the 800°C-annealed film was estimated. The coercivity of the annealed sample was very small and of the order of 102Oe at room temperature, meanwhile, the remanence coercivity obtained from DC demagnetization measurement was over 11kOe. This large difference was resulted from the co-existence of Fe-poor particles with different low anisotropy fields in the monolayered film.
|ジャーナル||Journal of Magnetism and Magnetic Materials|
|出版ステータス||Published - 2004 11|
|イベント||International Symposium on Advanced Magnetic Technologies - Taipei, Taiwan, Province of China|
継続期間: 2003 11 13 → 2003 11 16
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics