Structural and magnetic properties of L10/A1, FePt nanocomposites

In this work structural and magnetic properties of (L10-FePt/A1-FePt) exchange coupled nanocomposites are presented. Semi spherical “dome-like” nanocomposites with L10 FePt isolated nanoparticles and A1 FePt (fcc) cap layers were obtained by depositing A1-FePt on type L10 FePt nanoparticles in order to understand the influence of the soft magnetic layer thickness on the magnetic properties of the system. Epitaxial growth is confirmed by X-ray diffraction and TEM, while the coercivity decreases dramatically for the L10/A1-FePt system when the thickness of the A1-FePt cap layers is increased. This result can be used to realize ultrahigh magnetic recording media with tunable coercivity, suitable for conventional write heads.

► L10/A1-FePt, nanocomposites were produced on MgO substrates. ► The properties of nanocomposite with variation of A1 thickness were investigated. ► The long range order drastically decreases as the A1, thickness increases. ► The properties of nanocomposites, depends on its long range order. ► We propose a method, to tailor the coercivity of L10/A1-FePt nanocomposites.