Resistivity due to domain wall excitation in thin wires of ferromagnetic metals

We study the influence of thermal excitation of a domain wall (DW) on resis tivity in thin wires of disordered ferromagnetic metals. The negative corre ction for local conductivity ba due to the DW excitation is calculated by a ssuming that the elastic mean free time of spin-up electrons tau+ differs f rom that of spin-down electrons tau (-). When k(B)T much greater than h ome ga (0) (omega (0): attempt frequency of the DW) we obtain the correction ar ising inside the DW region as delta sigma/sigma (o) = -cT/E-pin ,where c ap proximate to (tau (+) - tau (-))(2)/(6 tau (+)tau (-)), sigma (0) and E-pin denote Drude conductivity and the pinning energy for the DW, respectively. A magnetic field H parallel to the wire reduces E-pin and thereby enhances the negative correction. When H is close to the coercive field H-c, we fin d that delta sigma>(*) over bar * (H)/sigma (o) proportional to -(1- H/H-c) (-1/2) as long as the DW is trapped at the pinning site.