Resistivity due to Domain Walls in Co Zigzag Wires

We report a clear manifestation of the negative magnetoresistance due to the domain wall of Co submicron zigzag wires in which the domain structures are artificially controllable by changing the orientation of the magnetic fields. The resistivity in the remanent state discontinuously drops when the domain configuration switches from the single domain to the multidomain. We attribute this to the domain wall, and deduce the decrease in the resistivity of $-1.8\mathrm{}\times {10}^{-6\mathrm{}}\Omega \mathrm{cm}$ assuming the wall thickness of 15 nm. The origin of the negative resistive contribution due to the domain wall is also discussed compared with the existing theories.