  We numerically study a matter wave interferometer realized by splitting a
trapped Bose-Einstein condensate with phase imprinting. We show that a simple
step-like imprinting pattern rapidly decays into a string of vortices that can
generate opposite velocities on the two halves of the condensate. We first
study in detail the splitting and launching effect of these vortex structures,
whose functioning resembles the one of a conveyor belt, and we show that the
initial exit velocity along the vortex conveyor belt can be controlled
continuously by adjusting the vortex distance. We finally characterize the
complete interferometric sequence, demonstrating how the phase of the resulting
interference fringe can be used to measure an external acceleration. The
proposed scheme has the potential to be developed into compact and high
precision accelerometers.
