Talbot-enhanced, maximum-visibility imaging of condensate interference

TL;DR

This paper reports the first observation of the Talbot effect with Bose-Einstein condensate interference fringes, demonstrating how it can both degrade and enhance fringe visibility and extend detection range in matter wave imaging.

Contribution

It introduces the first experimental observation of the Talbot effect with matter waves and shows how to use it to improve interference visibility and detection range.

Findings

Observed Talbot effect with Bose-Einstein condensates

Achieved >135% interference visibility using Talbot enhancement

Extended the focal range of matter wave detection systems

Abstract

Nearly two centuries ago Talbot first observed the fascinating effect whereby light propagating through a periodic structure generates a `carpet' of image revivals in the near field. Here we report the first observation of the spatial Talbot effect for light interacting with periodic Bose-Einstein condensate interference fringes. The Talbot effect can lead to dramatic loss of fringe visibility in images, degrading precision interferometry, however we demonstrate how the effect can also be used as a tool to enhance visibility, as well as extend the useful focal range of matter wave detection systems by orders of magnitude. We show that negative optical densities arise from matter-wave induced lensing of detuned imaging light -- yielding Talbot-enhanced single-shot interference visibility of >135% compared to the ideal visibility for resonant light.