Spatial interference from well-separated condensates

TL;DR

This paper demonstrates spatial interference between two well-separated Bose-Einstein condensates up to 0.25 mm apart, using magnetic levitation and optical plugs, with observed fringes matching theoretical predictions.

Contribution

It achieves the largest separation for condensate interference observed with this type of interferometer and provides experimental validation of fringe behavior under weak potential.

Findings

Interference observed at 0.25 mm separation

Fringe patterns match theoretical models

Weak potential influences on fringe separation confirmed

Abstract

We use magnetic levitation and a variable-separation dual optical plug to obtain clear spatial interference between two condensates axially separated by up to 0.25 mm -- the largest separation observed with this kind of interferometer. Clear planar fringes are observed using standard (i.e. non-tomographic) resonant absorption imaging. The effect of a weak inverted parabola potential on fringe separation is observed and agrees well with theory.