Ultracold atoms in a dipole trap in microgravity

TL;DR

This paper demonstrates an efficient method for producing ultra cold rubidium gases in microgravity using optical dipole traps and evaporative cooling during parabolic flights, enabling advanced quantum experiments in space.

Contribution

It introduces a novel evaporative cooling technique in microgravity with optical dipole traps, achieving rapid production of ultra cold atomic gases.

Findings

Produced 2.5×10^4 rubidium atoms below 100 nK in under 4 seconds

Demonstrated effective evaporative cooling in microgravity conditions

Enabled new possibilities for quantum sensors and fundamental physics experiments in space

Abstract

Most cold atoms experiments in microgravity platforms or in Space are achieved using atom chips, leading to limitations in terms of optical access and inhomogeneous magnetic fields. Optical dipole traps do not have these drawbacks but have difficulties producing atomic samples with a large number of atoms at ultra low temperature in the absence of gravity. Here, we report on an efficient evaporative cooling in two-crossed laser beams during parabolic flights. Time-averaged potentials combine the advantages of large capture volume and trap compression, increasing the initial phase space density and collision rate to favor the evaporative process. With this technique we demonstrate the production of an ultra cold gas of $2.5\times 10^4$ rubidium atoms at a temperature below 100 nK in less than 4 seconds. Our experiment paves the way for the development of quantum sensors applied to fundamental physics and geodesy as well as the study of ultracold atomic physics in Space.