We derive an expression for the phase shift of an atom interferometer in a gravitational field taking into account both the finite duration of the light pulses and the effect of a small perturbing potential added to a stronger uniform gravitational field, extending the well-known results for rectangular pulses and at most quadratic potentials. These refinements are necessary for a correct analysis of present-day high-resolution interferometers.

• Received 31 December 2018

DOI:https://doi.org/10.1103/PhysRevA.99.033619