Spin wave theory of double exchange ferromagnets
We construct the 1/S spin wave expansion for double exchange ferromagnets at T = 0. It is assumed that the value of Hund's rule coupling, J(H), is sufficiently large, resulting in a fully saturated, ferromagnetic half-metallic ground state. We evaluate corrections to the magnon dispersion law, and we also find that, in contrast to earlier statements in the literature, magnon-electron scattering does give rise to spin wave damping. We analyze the momentum dependence of these quantities and discuss the experimental implications for colossal magnetoresistance compounds.
Golosov
DI
NORDITA, Blegdamsvej 17, DK-2100 Copenhagen O, Denmark.