Magnetic properties of X_(0.5)Mn_(0.5)/Cu(001) overlayers, X = Fe, Mn, and Ir: Ab-initio calculations

摘要

We investigated by theoretical means the magnetic structure and the magnetocrystalline anisotropy of X_(0.5)Mn_(0.5) bi-layer systems on Cu(001) surfaces and their corresponding ordered bulk alloys. The calculations were performed using density functional theory (DFT) as implemented in the Full-potential linearized augmented plane wave (FP-LAPW) method. The c∈(2×2) chemically ordered X_(0.5)Mn_(0.5)/Cu(001) structures exhibited different magnetic configurations, frustrated antiferromagnetic (AF) ones in case of the Fe_(0.5)Mn_(0.5) overlayer, which is an indication of the appearance of noncollinear magnetism. Interestingly, in case of the Co_(0.5)Mn_(0.5) system we found a ferromagnetic ordering and an AF ground state in the case of the Ir _(0.5)Mn_(0.5) overlayer. The magnetocrystalline anisotropy energies (MAE) are found to be -0.08 (-2.5), 0.40 (0.68), and 6.90 (-0.82) meV/cell for X_(0.5)Mn_(0.5) bulk (overlayer) systems. The out-of-plane easy axis in Fe_(0.5)Mn_(0.5) and Ir _(0.5)Mn_(0.5) overlayer systems may be promising for potential perpendicular recording applications.