Synthesis and structure of isolated L1(0)FePt particles

Isolated FePt particles were fabricated by taking advantage of overgrowth o f Fe on Pt particles and subsequent annealing at 873K. The annealing lead t o the formation of ordered tetragonal (L1(O)) FePt particles with three ort hogonal variants, The average size of FePt particles could be adjusted to l ess than 10 um and no significant grain coarsening occurred upon annealing due to the existence of an amorphous Al2O3 layer. Nano-beam electron diffra ction revealed that the lattice constant ratio c/a was approximately 0.97 f or the annealed FePt particles with Fe composition close to 50 at.%.