Magnon scattering processes and low-temperature resistivity in CMR manganites

Low-temperature resistivity of CMR manganites is investigated. At the ground state, conduction electrons are perfectly spin polarized, which is called half-metallic. From one-magnon scattering processes, it is discussed that the resistivity of a half metal as a function of temperature scales as ρ( T)- ρ(0)∝ T³. We take (Nd _0.8Tb _0.2) _0.6Sr _0.4MnO ₃ as an example to compare theory and experiments. The result is in a good agreement.