The Influence of Spin Orientation and Alloying on Magnetism and Work Function for Fex-1Mnx/Fe (001) Films

Abstract

By using first-principles methods based on density functional theory (DFT), we investigated the magnetism and work function of Fex-1Mnx/Fe (001) films with different spin arrangements (parallel (PL), antiparallel (APL1) and mixed (APL2)) for Mn and Fe atoms. The calculation shows that the spin arrangement and alloying have evident impact on the work function and moment of Fex-1Mnx/Fe (001) films. For Mn/Fe (001), the spin arrangement affects evidently the geometrical structure, work function and magnetism of the system. Moreover, the work function for non-magnetic (NM) state is found to be higher than that for magnetic state, and the work function of Mn/Fe (001) with PL state is less than that with APL2 state. For Fex-1Mnx/Fe (001), with increased Mn doping content, the Fe moments in the second layer decrease and their values are all less than the bulk value of Fe atom, which is due to the antiferromagnetic coupling between Mn and Fe atoms. Furthermore, we found that the surface alloying can have an impact on the work function of Fex-1Mnx/Fe (001), but the role of spin polarization is also quite important.