The magnetic variation of hexagonal FeGe bulk depends on stress controlling

We report a system study of the stress regulates the electronic structure and magnetic property of FeGe. The density states of Fe was more than 85% contribution comes from Fe 3d, the density states of Ge mainly contributed from Ge 4p and Ge 4s, and the Fe 3d spin was induce the Ge 4p electron transfer. The induction effect increased the electron energy of germanium, weakened the Fe spin density states. The magnetic moment is 1.15μB per FeGe molecule with the stress of 0 GPa, and the magnetic moment is almost linearly decrease with the stress increasing from −30 GPa to 30 GPa. The magnetic of FeGe mainly comes from the unoccupied Fe 3d orbital, the Fe 3d is positive spin-polarization state and the spin-polarization strength is decreased, the Ge1 4p and Ge2 4p are negative spin-polarization state and the spin-polarization strength are increased. The main reason is that the charge of Fe are negative whereas the Ge1 and Ge2 atoms are positively charged, the Fe atom lost charge, and the charge transferred to the Ge atom, under the stress. But the total numbers of gain and lose charge is not equal, so the FeGe electron system may be exist hybridization between the Fe 3d state and Ge 4p state. Moreover, electrons-spin polarization is relevant to the structure parameters of the FeGe system, and control spin-polarized electronic behavior by means of adjusting ferromagnetic.