Measurement of the Weak-Localization Complex Conductivity at 1 GHz in Disordered Silver Wires

The complex magnetoconductivity of disordered quasi-one-dimensional Ag wires at 1 GHz and at 200 Hz was measured. Because 1 GHz is of the same order as the dephasing rate, it was possible to observe the frequency dependence of weak localization. Both the real and imaginary parts of the conductivity at 1 GHz are in good agreement with theory. The data yield an accurate value for the electron diffusion constant, which is not well determined by dc measurements, and support the theory of weak localization at finite frequency, due originally to Gor'kov, Larkin, and Khmel'nitskii.