Effect of an ac electric field on phase coherence in thin metal films

We have studied the effect of a high-frequency (9 GHz) electric field on electron phase coherence in thin Sb and AuPd films. The phase coherence is monitored through the effect of weak localization on the conductance. We find that, as predicted theoretically, an ac field disrupts phase coherence, and hence quenches weak localization. For Sb, our results are in good agreement with the theory. However, for AuPd the theory predicts a smaller effect than is observed experimentally.