Effect of partial phase coherence on Aharonov-Bohm oscillations in metal loops

The averaging of Aharonov-Bohm oscillations caused by incomplete phase coherence has been studied in two Sb rings. In these devices, the phase-coherence length L_φ can be determined independently from an analysis of the weak localization contribution to the magnetoconductance (ΔGC) or from the amplitude of the conductance fluctuations. We find that the Aharonov-Bohm oscillations decrease as exp(-LL_φ) where L is the sample length. The values of L_φ inferred from ΔGC qualitatively predict the temperature dependence of the conductance fluctuations.