Contrast preservation in light-pulse atom interferometry

Atom-interferometer sensitivity is often limited by loss of interferometer contrast arising from inhomogeneous dephasing and detection noise. While sensitivity can be increased by enlarging the space–time area via large momentum transfer and longer interrogation times, these gains are frequently limited by reduced visibility. We present ongoing work on contrast preservation in a light-pulse atom interferometer, with emphasis on experimentally relevant limitations encountered when operating at larger momentum separation and longer times. We describe approaches including shaping the transverse spread of the atomic ensemble and adjustments to interferometer geometry.