KONDO EFFECT IN ONE-DIMENSIONAL AU(FE)

We have investigated dimensional crossover with regard to the Kondo effect in Au doped with small amounts of Fe [Au(Fe)]. The samples were narrow strips, and had a constant thickness (almost-equal-to 150 angstrom) that was much smaller than their width. When the strip width w was very large, we found a contribution to the resistance from the presence of the Fe, which we identify as due to the Kondo effect. As w was reduced below about 1500 angstrom this Kondo contribution to the resistivity decreased significantly. This behavior is similar to that found in previous studies of the three- to two-dimensional Kondo crossover, and implies that there is an intrinsic length scale of approximately 1500 angstrom for the Kondo effect in Au(Fe). These results are discussed in light of recent theoretical work.