Scalar Aharonov-Bohm effect for ultracold atoms

The scalar Aharonov-Bohm effect with a time-dependent magnetic field was investigated for ultracold sodium atoms using the time-domain atom interferometer. The 38 interference fringes with almost the same amplitude verified the nondispersivity of this effect. The measured phase shift as a function of the strength of the applied magnetic field agreed with the predicted one within an accuracy of 3%. With a weak magnetic field orthogonal to the quantization axis, the phase shift was in proportion to the variation of the strength of the resultant magnetic field.