Interference of Bose-Einstein Condensates on an Atom Chip

TL;DR

This paper demonstrates the use of an atom chip to split a Bose-Einstein condensate into two parts, observing interference patterns and phase variations caused by the splitting process.

Contribution

It introduces a microfabricated atom chip technique for splitting condensates and studies the resulting interference and vortex formation.

Findings

Observation of matter wave interference patterns

Detection of phase randomness between condensates

Vortex formation due to potential perturbations

Abstract

We have used a microfabricated atom chip to split a single Bose-Einstein condensate of sodium atoms into two spatially separated condensates. Dynamical splitting was achieved by deforming the trap along the tightly confining direction into a purely magnetic double-well potential. We observed the matter wave interference pattern formed upon releasing the condensates from the microtraps. The intrinsic features of the quartic potential at the merge point, such as zero trap frequency and extremely high field-sensitivity, caused random variations of the relative phase between the two split condensates. Moreover, the perturbation from the abrupt change of the trapping potential during the splitting was observed to induce vortices.