Nondispersive phase of the Aharonov-Bohm effect

Abstract
An essential signature of the topological nature of all Aharonov-Bohm type phases is that they are nondispersive, i.e., independent of the velocity (wavelength) of the interfering particles. This implies that an Aharonov-Bohm phase shift can greatly exceed the usual limit given by the coherence length of the interfering beams. We report the results of a polarized neutron experiment demonstrating this property for a spin-rotation analog of the scalar Aharonov-Bohm effect.