Magnetocrystalline properties of Iron-Platinum (L10-FePt) nanoparticles through phase transition

Farahmandjou, M

doi:10.18869/acadpub.ijpr.16.1.1

Magnetocrystalline properties of Iron-Platinum (L10-FePt) nanoparticles through phase transition

Author

M Farahmandjou

https://doi.org/10.18869/acadpub.ijpr.16.1.1

Abstract

High magneto- crystalline anisotropy (ku=7×106j/m3) of L10-FePt nanoparticles are an excellent candidate for ultra high-density magnetic recording. The 4 nm FePt nanocrystals were prepared by superhydride reduction of FeCl2·4H2O and Pt(acac)2 precursors in the phenyl ether by reduction of the 1, 2-hexadecanediol and LiBEt3H superhydride. The crystal and magnetic structures were studied by XRD and VSM analysis. By TEM and EDS analyses the size distribution and molar concentration of Fe/Pt of the nanoparticles were determined. The results showed that the particles are first superparamagnetic before heat treatment and then a phase transition accrue from disorder fcc to order fct structure after annealing. Finally, the phase transition leads the magnetic anisotropy of hard FePt nanoparticles to increase to 7 kOe.

Keywords

anisotropy

L10-FePt

magneto- crystalline

nanocrystals

phase transition

superparamagnetic

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