Electronic structures and spin magnetic properties of CoFe: Lattice strain effects

The effects of lattice strain on the electronic structures and the spin magnetic properties of CoFe in the CsCl (B2) structure were studied using first-principles electronic-structure calculations based on the density functional theory. The calculations in this study showed that the lattice stain induces significant changes in the peak positions of the majority-spin and the minority-spin densities of states: In the case of lattice expansion, band narrowing was observed while in the case of lattice compression, band broadening was observed. As a result, when the lattice strain of CoFe was increased to 4. 7%, the minority-spin density of states at the Fermi energy decreased by 32% as compared to that of the unstrained CoFe. This suggests that lattice strain can play an important role in the functioning of spin electronic devices of CoFe.