Anti-site-induced diluted magnetism in semiconductive CoFeTiAl alloy

The spin-polarized electronic band structure calculations are carried out to theoretically investigate the effect of anti-site disordering to the electronic band structure and magnetic properties of LiMgPdSb-type CoFeTiAl alloy. We found that the Co-Ti and Fe-Ti antisite disordering can induce the diluted magnetism in CoFeTiAl alloy. Especially, the Fe-Ti antisite disordering can induce a 100% spin polarization at the Fermi level at a certain degree of anti-site disordering. The Co-Fe antisite disordering is easy to occur in CoFeTiAl alloy but has little effect on the semiconductive characteristic and magnetic properties. The Co, Fe and Ti atoms at the anti-site contribute the magnetization in CoFeTiAl alloy. The diluted magnetism in CoFeTiAl alloy can be induced by the anti-site disordering instead of the introduction of magnetic dopant elements.