Low-temperature resistivity in a nearly half-metallic ferromagnet

In a nearly half-metallic ferromagnet, such as a material exhibiting "colossal" magnetoresistance, the minority spin electrons close to the band edge at the Fermi energy are Anderson localized due to disorder; thus only majority electrons conduct current. This presents a unique electronic structure for which the linear response Boltzmann equation involving the scattering of a single magnon is exactly solvable. The solution yields a temperature dependent resistivity that scales as T-2.5 above approximately 60 K and contains a T-1.5 contribution below this temperature, and has a dependence on the magnetic field consistent with experiments. [S0031-9007(99)09140-1].