  We have investigated the time-dependent fluctuations in electrical
resistance, or noise, in high quality crystalline magnetic nanowires within
nanoporous templates. The noise increases exponentially with increasing
temperature and magnetic field, and has been analyzed in terms of domain wall
depinning within the Neel-Brown framework. The frequency-dependence of noise
also indicates a crossover from nondiffusive kinetics to long-range diffusion
at higher temperatures, as well as a strong collective depinning, which need to
be considered when implementing these nanowires in magnetoelectronic devices.
