Phase uncertainty and loss of interference in a simple model for mesoscopic Aharonov-Bohm experiments

Abstract

Incoherence introduced in two-path experiments by interactions with scatterers in thermal equilibrium is examined with an energy-momentum approach previously used for the M\ossbauer effect. Oscillations in intensity with variations in the magnetic flux are shown to be insensitive to random phase changes in the individual scattering amplitudes. Inelastic incoherent scattering may be suppressed when there are a large number of scatterers. A small loss of phase coherence negligible in cases of practical interest can occur even via elastic scattering, which does not perturb the environment. The temperature dependence of the loss of interference, analogous to the Debye-Waller factor, may be tested by experiment.