Perpendicular magnetic anisotropy in nearly fully compensated ferrimagnetic Heusler alloy Mn0.75Co1.25VIn: An ab initio study

Abstract

First principles calculations are reported on perpendicular magnetic anisotropy (PMA) in nearly fully compensated ferrimagnetic Heusler compound Mn0.75Co1.25VIn. The structural, electronic and magnetic properties of Mn2−xCoxVIn Heusler compounds (x=0.0, 0.25, 0.50, 0.75, 1.0, 1.25, and 1.75) have been investigated using Density Functional theory (DFT) as implemented in the Vienna ab initio simulation package (VASP). The Perdew Burke Ernzerhof parametrization of the generalized gradient approximation (GGA) was used to treat the exchange and correlation in the system. The crystal structure of the compounds with x=0.75, 1.00 and 1.25 are found to be tetragonally distorted. While the former exhibits inplane magnetocrystalline anisotropy (IMA) energy of 0.035meV, the latter two exhibit perpendicular magnetocrystalline anisotropy (PMA) energy of 11.700meV and 96.800meV respectively. Additionally, the magnetic moments for x=0.75 and 1.25 are found to be ∼0.5µB/f.u. while for x=1.00, it is found to be ∼0µB/f.u., in agreement with the Slater Pauling rule for half metallic systems. Through Co replacement of Mn in Mn2VIn which is not half metallic at the optimized volume, a composition whose crystal structure is tetragonally distorted is found, which is not only a highly spin polarized nearly fully compensated ferrimagnet but also exhibits PMA.