Magnetic and electronic properties of rare earth free Fe5Ge3 magnets

Calculations based on density functional theory have been performed to investigate the potential of the rare earth free Fe5Ge3 magnets for applications in spintronics. We evaluated properties intrinsically important for spintronics like spin polarization and magnetic anisotropy for the case of pure Fe5Ge3 and for the case of natural dopant atoms such as Mn, Co and Ni. The results indicate that the pure system has a spin polarization of 28% at the Fermi level. An increase in the spin polarization can be obtained by incorporating Co, Ni and Mn atoms as dopants being the maximum value of 57% obtained by Co doping at type-I sites. A certain control of the magnetocrystalline anisotropy can be also obtained by doping, indicating that the Fe5Ge3 system is suitable for spintronic applications.