Optical Weak Link between Two Spatially Separate Bose-Einstein Condensates

TL;DR

This paper demonstrates an optical coupling method between two spatially separated Bose-Einstein condensates using Bragg beams, revealing phase-dependent atomic currents and proposing a Josephson optical coupling in a ring geometry.

Contribution

It introduces a novel optical weak link technique for coupling separate condensates and explores phase-dependent atomic currents, advancing control over quantum matter waves.

Findings

Atomic currents depend on relative phase and controllable coupling phase.

Symmetric and antisymmetric correlations observed in outcoupled atom fluxes.

Method monitors slow relative motions of condensates.

Abstract

Two spatially separate Bose-Einstein condensates were prepared in an optical double-well potential. A bidirectional coupling between the two condensates was established by two pairs of Bragg beams which continuously outcoupled atoms in opposite directions. The atomic currents induced by the optical coupling depend on the relative phase of the two condensates and on an additional controllable coupling phase. This was observed through symmetric and antisymmetric correlations between the two outcoupled atom fluxes. A Josephson optical coupling of two condensates in a ring geometry is proposed. The continuous outcoupling method was used to monitor slow relative motions of two elongated condensates and characterize the trapping potential.