We analyze the origin of the electrical resistance arising in domain walls of perpendicularly magnetized materials by considering a superposition of anisotropic magnetoresistance and the resistance implied by the magnetization chirality. The domain wall profiles of $L{1}_0\mathrm{\text{−}}\mathrm{FePd}$ and $L{1}_0\mathrm{\text{−}}\mathrm{FePt}$ are determined by micromagnetic simulations based on which we perform first-principles calculations to quantify electron transport through the core and closure region of the walls. The wall resistance, being twice as high in $L{1}_0\mathrm{\text{−}}\mathrm{FePd}$ than in $L{1}_0\mathrm{\text{−}}\mathrm{FePt}$, is found to be clearly dominated in both cases by a high gradient of magnetization rotation, which agrees well with experimental observations.

• Received 30 June 2011

DOI:https://doi.org/10.1103/PhysRevLett.108.077201