First principles study of Ag, Au, and Cu surface segregation in FePt-L10.

Doping FePt nanoparticles could be a possible approach to achieve high L1₀ order and magnetic anisotropy. To address stability, first-principles studies of surface segregation of dilute Ag/Au/Cu solutes at and near the (001)/(100)/(111) surfaces of FePt-L1₀ are performed. It is found that a strong surface segregation tendency at first outer layer is present in all the cases. For Cu, segregation is less than half of Ag and Au. Ag and Cu segregate to Fe sites at surfaces and preferentially substitute for Fe in the bulk, whereas Au substitutes for Fe at surfaces and for Fe and Pt in the bulk. [ABSTRACT FROM AUTHOR]