EFFECT OF TRANSITION METAL DOPING ON MAGNETIZATION AND SPIN TRANSPORT OF DOMAIN WALL MADE BY NICKEL ATOMIC CHAIN

Abstract

Based on density functional theory and nonequilibrium Green’s function method, we study the magnetic order and collinear/noncollinear spin transport of 180[Formula: see text] domain wall (DW) made by transition metal (TM)-doped Ni atomic chain. The results show that the TM doping reproduces characteristic features depending on the type of TM elements, the number of dopants and the initial magnetization distribution. In the collinear magnetization, which is obtained from the initial condition of abrupt DW, the two dopants show symmetric features while the single dopant presents a varying magnetic moment on the TM dopant when the number of 3d electrons of dopant increases. As the magnetization is noncollinear (spiral-like), the magnetization becomes complicated. For instance, the rotation sense of magnetization changes from clockwise to counter-clockwise for some TM dopants. In addition, the transmission of doped Ni chain shows two scattering mechanisms, i.e. electronic scattering due to quasi-bound state and due to the spin-flip scattering. Our results reported here provide considerable insights into the doping effect on magnetization and spin transport of atomic-scale DW.