Structure and interference of ultracold atoms in circular waveguides

Simple circular waveguides promise to be an ideal architecture for building high-precision matter-wave interferometers that exploit the coherent source of atoms provided by Bose-Einstein condensates (BECs). We perform numerical calculations of the time-dependent Gross-Pitaevskii equation in one and two dimensions to simulate gravity-induced quantum interference for counterpropagating BECs in a circular waveguide. The emphasis being on the role that nonlinear interactions have on the feasibility of interferometric measurements. Our results vividly illustrate the many challenges in performing the corresponding experiments.