| Close to the Curie temperature of an itinerant ferromagnet the magnetic correlation length becomes large compared to the electronic mean free path. In this regime, which can be broad in the presence of strong disorder, the electron dynamics is diffusive on the length scale of the magnetic fluctuations. This requires one to go beyond the Boltzmann-type description used in previous works, such as the theory for the resistive anomaly proposed by Fisher and Langer in 1968. Our approach combines ideas from the theory of random media and from mesoscopic physics. We find a fluctuation-induced contribution to the resistivity that scales with T-Tc to the power 1/2, assuming Gaussian magnetic fluctuations, a much stronger singularity than found from the Fisher-Langer theory. Our results are relevant for ferromagnets with low Curie temperatures, such as SrRuO3 or diluted magnetic semiconductors, whose mobility is limited by disorder. |