Aharonov-Bohm periodicity: current I(Phi) has period Phi_0 = h/e (U(1) covering space of annulus)

Aharonov-Bohm mesoscopic-ring framework (AB 1959 Phys Rev 115, 485). Setup: a metal ring encloses a magnetic flux Phi; electrons encircle the flux and acquire a Berry-Aharonov-Bohm phase exp(i*2*pi*Phi/Phi_0) with flux quantum Phi_0 = h/e.…