  The Aharonov-Bohm effect is a physical phenomenon where the vector potential
induces a phase shift of electron wavepackets in regions with zero magnetic
fields. It is often referred to as evidence for the physical reality of the
vector potential. A similar effect can be observed in solid-state systems,
where the Berry connection can influence electron dynamics. Here, we show that
in chiral-symmetric processes the Berry connection determines an observable
effect on the mean chiral displacement of delocalized wavefunctions. This
finding is supported by a photonic experiment realizing a topological quantum
walk, and demonstrates a new effect that can be attributed directly to the
presence of a gauge field.
