Interaction between Spin Waves and Conduction Electrons in Ferromagnetic Metals

With a view toward understanding ferromagnetic resonance line widths in metals, the relaxation time due to the spin wave-conduction electron interaction has been calculated. The effect due to the interaction of ferromagnetic spins with conduction electron currents is much more important than that due to the interaction of ferromagnetic spins with conduction electron spins. In nickel, for temperatures between 4^∘{}K and 300^∘{}K, the former process yields a relaxation time 10^-8-10^-7 sec, while the latter yields 10^-3-10^-4 sec. The interactions do not appear to be strong enough to account for the observed line widths.