This electric Aharonov-Bohm effect has not been experimentally observed, unlike the magnetic effect. It not generally feasible to trap an electron at a "mirror" in the interferometer while the potential is turned on and off, which is necessary in this setup to ensure that the electron stays in a region where the field is 0 while the potential is varied. Proposals for experimentally observing the effect instead involve shielding the electron from any electric field by having it travel through a conducting cylinder while the potential is varied. In contrast, one experiment proposal for the gravitational Aharonov-Bohm effect actually does involve trapping atoms (which play an analogous role to electrons in the experiment proposal) and holding them in a region where the gravitation field is zero using optical lattices.