Suppression of the weak-localization effect due to a domain wall in mesoscopic wires of ferromagnetic metals

We study the weak-localization (WL) effect in mesoscopic wires of ferromagn etic metals, focusing on the decoherence caused by a magnetic domain wall ( DW). The decoherence leads to suppression of the WL correction to conductan ce. A real-space approach is presented to describe the WL effect which expl icitly takes into account the location of, a DW. IT the length L of a wire is much smaller than the phase coherence length L-phi, the WL correction is shown lo depend on the location of the DW. In the opposite limit of L much greater than L-phi much greater than W (W: thickness of the DW), it is sho wn that the DW reduces the WL correction by a factor of (1 - W/2L) compared with that in the absence of the DW. The influence of the DW on the amplitu de of the Altshuler-Aronov-Spivak oscillation in a metallic ring partially replaced by a ferromagnetic wire is also discussed.