First-principles study on surface reconstruction and magnetic phase stability of an FePt3 film on a Pt(110) substrate

Abstract

The FePt3 alloy is one of the most investigated materials for high density storage applications due to its rich variety of magnetic structures which transform sensitively depending on change in its local structure. Here, we present the ab-initio total energy and electronic structure calculations within the framework of density functional theory for an FePt3 film of 0.5 nm in thickness on a Pt (110) surface. The results show that a missing-row surface reconstruction along the \([1\overline 1 0]\) direction is energetically more stable over the unreconstructed clean surface, which is attributed to the energy gain by the spill out of p-electron charge to the large facet area from Pt atoms at the second and third atomic layers. The missing-row reconstruction is found to enhance the stability of the ferromagnetic phase over the antiferromagnetic bulk ground-state phase and to induce possible concurrence of a meta-stable atomic structure with an in-plane anti-phase boundary along the orientation of missing-row in addition to the conventional L12 surface, implying the observation of various magnetic phases.