E. Kogan et al., Localization and dephasing driven by magnetic fluctuations in low carrier density colossal magnetoresistance materials, EUR PHY J B, 9(3), 1999, pp. 373-376
Localization and dephasing of conduction electrons in a low carrier density
ferromagnet due to scattering on magnetic fluctuations is considered. We c
laim the existence of the "mobility edge", which separates the states with
fast diffusion and the states with slow diffusion; the latter is determined
by the dephasing time. When the "mobility edge" crosses the Fermi energy a
large and sharp change of conductivity is observed. The theory provides an
explanation for the observed temperature dependence of conductivity in fer
romagnetic semiconductors and manganite pyrochlores.