We establish the fundamental properties of two classes of interferometers: those forming a pattern in momentum space, based on the superposition of two different momentum states and described by their relative propagation, and those forming a pattern in real space, based on two or more interferometer arms and described by the propagation between their local ends. These two classes are characterized by different sensitivity functions and different noise sources; we will compare the sensitivity functions of two possible configurations of atom interferometer and identify the most promising realization, with a view to applications to tests of general relativity and investigations of alterations of the spacetime curvature.

• Received 10 November 2008

DOI:https://doi.org/10.1103/PhysRevD.79.042001