Absence of size dependence of the Kondo resistivity

Abstract

We have measured the low temperature resistivity of AuFe wires in the dilute magnetic impurity limit as a function of wire width, temperature, and magnetic field. When the width dependence of the electron-electron interaction contribution to the resistivity is taken into account, the temperature dependence of the remaining Kondo contribution to the resistivity of all samples with the same impurity concentration is identical. Similar behavior is observed for the magnetic field dependent resistivity. Thus, the Kondo contribution to the resistivity is independent of width down to 38 nm, much smaller than the Kondo length ${\ensuremath{\xi}}_{\mathit{K}}$=\ensuremath{\Elzxh}${\mathit{v}}_{\mathit{F}}$/${\mathit{k}}_{\mathit{B}}$${\mathit{T}}_{\mathit{K}}$\ensuremath{\approxeq}10 \ensuremath{\mu}m.