Effect of local magnetic moments on the metallic behavior in two dimensions

The temperature dependence of conductivity sigma(T) in the metallic phase o f a two-dimensional electron system in silicon has been studied for differe nt concentrations of local magnetic moments. The local moments have been in duced by disorder, and their number was varied using substrate bias. The da ta suggest that in the limit of T --> O the metallic behavior, as character ized by d sigma/dT < 0, is suppressed by an arbitrarily small amount of sca ttering by local magnetic moments.