Transport at low temperature in amorphous magnetic metals (invited)

Abstract

The scaling theory of conduction for a noninteracting electron gas in a disordered system at T = 0 is reviewed and the conductivity at various length scales obtained. The concepts of the mean free time between inelastic collisions and the corresponding inelastic length l_in, are introduced. The conductivity for a dirty metal is obtained as a function of temperature at low temperatures in terms of l_in(T). For the case of a disordered magnetic metal the effect of the temperature‐dependent magnetic disorder is introduced and several possible typical situations schematically analyzed. The effect of electron‐electron interactions is briefly discussed, as determining the effective inelastic length and a simple qualitative picture of conduction as a function of temperature suggested. Some cautionary remarks about the testing of these ideas by experiments are made.