Large Uniaxial Magnetic Anisotropy of Hexagonal Fe-Hf-Sb Alloys

We theoretically investigate the electronic and magnetic structure of Fe2Hf. The density functional theory calculations are shown to produce the negative, easy-plane, magnetic anisotropy in the hexagonal Fe2Hf. Antimony substitution suppresses the planar magnetization direction and favors the uniaxial magnetic anisotropy, in agreement with experimental observations. Our study suggests the possibility of the chemical control of the magnetic anisotropy in Fe2Hf by Sb substitution, and illustrates the potential of (Fe,Sb)2+xHf1-xLaves phase alloys for the permanent magnet applications.