Aharonov-Bohm Effect
Quantum interference shifted by enclosed magnetic flux — with no classical force
The Aharonov-Bohm effect (1959): a charged quantum particle acquires a phase shift
Δφ = 2πΦ/Φ₀ when encircling a solenoid, even though the magnetic field B=0 along
the particle's path. Only the vector potential A matters — a profoundly non-classical result.
The interference pattern shifts continuously with enclosed flux Φ; fringe pattern is periodic with
period Φ₀ = h/e (flux quantum).