# Compact cold atom clock for on-board timebase: tests in reduced gravity

## TL;DR

This paper introduces a compact cold atom clock utilizing isotropic light cooling and Ramsey interrogation, demonstrating its potential for space applications through successful tests in simulated microgravity.

## Contribution

It presents a novel, compact atomic clock design with rapid cooling and high precision, suitable for on-board use in space environments.

## Key findings

- Achieved record narrow fringes in microgravity conditions
- Demonstrated rapid cooling cycle of 100 ms
- Validated technology readiness for industrial transfer

## Abstract

We present a compact atomic clock using cold rubidium atoms based on an isotropic light cooling, a Ramsey microwave interrogation and an absorption detection. Its technology readiness level is suitable to industrial transfer. We use a fibre optical bench, based on a frequency-doubled telecom laser. The isotropic light cooling technique allows us to cool down the atoms in 100 ms and works with a cycle time around 200 ms. We carried out measurements in simulated microgravity and obtained the narrowest fringes ever recorded in microgravity.