A cluster expansion and ab initio studies of L10 Mn-Pt–Co alloys

Abstract

Ordered alloys based on manganese-platinum (Mn-Pt) are receiving increased attention, mostly in developing magnetic materials for data storage applications. In particular, Mn-Pt–Co appears to be one of the most promising alloys due to its ferromagnetic behaviour at 0 K. There have been numerous efforts to improve the ferromagnetic properties of MnPt through alloying with cobalt (Co) and other elements but the underlying thermodynamic stability remains unclear. In this study, the phase and mechanical stability of L10 Mn-Pt–Co alloys are examined using Cluster Expansion (CE) and density functional theory (DFT). A total of 37 new structures for L10 PtMn1-xCox (Mn-site) were generated by CE. Five (5) stable structures were predicted with negative formation energies for L10 PtMn1-xCox alloys. Furthermore, the magnetic and elastic properties of the ground state structures are calculated using DFT. These findings could have important implications in designing new magnetic materials for spintronic applications.