Magnetic properties of MnBi based alloys: First-principles calculations for MnBi-Co and MnBi-Co-Fe cases

Abstract

First-principles calculations of fundamental magnetic properties were performed for ordered MnBi, MnBi-Co, and MnBi-Co-Fe alloys to evaluate maximum energy product (BH)max. Full potential linear-augmented plane wave (FLAPW) and linear-muffin-tin-orbital (LMTO) calculations using density functional theory (DFT) within the local spin density approximation (LSDA) were used and found to give a reasonable description of saturation magnetization (Ms), effective anisotropy constant (Keff), and Curie temperature (Tc) for NiAs-structured MnBi crystal. We found that upon addition of Co, the Ms and Keff increased, while T c reduced. The magnetic anisotropy changed from weak anisotropy easy plane for MnBi to the strong easy axis anisotropy for MnBi-Co and MnBi-Co-Fe. © 2013 © 2013 Author(s).