Improving the accuracy of atom interferometers with ultracold sources

TL;DR

This paper demonstrates that using ultracold atoms in atom interferometers significantly improves measurement accuracy by reducing wavefront aberration effects, achieving record-breaking inertial sensor precision.

Contribution

The study introduces a method to correct wavefront aberration biases in atom interferometers using ultracold atom sources, enhancing their accuracy.

Findings

Achieved gravity measurement uncertainties of 10 nm/s^2.

Developed a model to correct wavefront aberration effects.

Demonstrated potential for further accuracy improvements at lower temperatures.

Abstract

We report on the implementation of ultracold atoms as a source in a state of the art atom gravimeter. We perform gravity measurements with 10 nm/s 2 statistical uncertainties in a so-far unexplored temperature range for such a high accuracy sensor, down to 50 nK. This allows for an improved characterization of the most limiting systematic effect, related to wavefront aberrations of light beam splitters. A thorough model of the impact of this effect onto the measurement is developed and a method is proposed to correct for this bias based on the extrapolation of the measurements down to zero temperature. Finally, an uncertainty of 13 nm/s 2 is obtained in the evaluation of this systematic effect, which can be improved further by performing measurements at even lower temperatures. Our results clearly demonstrate the benefit brought by ultracold atoms to the metrological study of free falling atom interferometers. By tackling their main limitation, our method allows reaching record-breaking accuracies for inertial sensors based on atom interferometry.