– A model of magnetic interactions in the ordered ferromagnetic FePt is proposed on the basis of first-principles calculations of non-collinear magnetic configurations and shown to be capable of explaining recent measurements of magnetic-anisotropy energy (MAE). The site (Fe,Pt) resolved contributions to the MAE have been distinguished with small Fe easyplane and large Pt easy-axis terms. This ...

FePt nanoparticles have great application potential in advanced magnetic materials such as ultrahigh-density recording media and high-performance permanent magnets. The key for applications is the very high uniaxial magnetocrystalline anisotropy of the L10-FePt phase, which is based on crystalline ordering of the face-centered tetragonal (fct) structure, described by the chemical-ordering param...

Dithiocarbamate chemistry is used as a crosslinking tool to fabricate FePt colloidal microcapsules which provide a versatile scaffold for "host-guest" recognition at the liquid-liquid interface.

In the first part of this thesis, we study the magnetization reversal process of FePtnanowires with high magnetocrystalline anisotropy. When reducing the wire width below themean dendrite width, the magnetization reversal favors a transition from the dendrite growth tothe propagation of a single domain wall (DW). Further decreasing of the width towards thedisorder length and/or ...

FePt nanoparticles with a size of 4 nm were prepared by the polyol process according to the reaction route described by Sun et al. The particles were annealed at 550 C and 580 C for 30min in N2 atmosphere, developing coercivities of up to 8.8 kOe. From conventional transmission electron microscopy the coherence lengths of the self-assembly were found to be as large as 10mm in the as-prepared st...

40 nm thick CoPt and FePt films were prepared on oxidized Si substrates with 10 nm MgO underlayers. The maximum coercivity ( ) for CoPt films was found to be 10 kOe after annealing at 700 C for 20–30 minutes (min). Structural analysis showed a significant amount of FCC phase as well as the ordered L10 phase in these films. FePt films showed an abrupt increase of ordered volume fraction and in t...

AgGaS2 (AGS) nanocrystals that exist in the orthorhombic phase were successfully prepared for the first time through a one-pot colloidal synthetic strategy using suitable coordinating solvents. These orthorhombic AGS nanocrystals were found to display great potential in visible-light-driven photocatalysis.