# Design and characterisation of a compact magnetic shield for ultracold atomic gas experiments

## TL;DR

This paper presents the design, construction, and testing of a compact magnetic shield that significantly reduces external magnetic noise, enabling improved ultracold atomic gas experiments with enhanced environmental control.

## Contribution

The authors developed a novel, optimized magnetic shield with validated performance, suitable for ultracold atomic experiments, combining finite-element simulations with experimental verification.

## Key findings

- Remnant field noise of 2.6 microGauss achieved
- Magnetic field suppression exceeds five orders of magnitude
- Design is validated by experimental measurements and simulations

## Abstract

We report on the design, construction, and performance of a compact magnetic shield that facilitates a controlled, low-noise environment for experiments with ultracold atomic gases. The shield was designed to passively attenuate external slowly-varying magnetic fields while allowing for ample optical access. The geometry, number of layers and choice of materials were optimised using extensive finite-element numerical simulations. The measured performance of the shield is in good agreement with the simulations. From measurements of the spin coherence of an ultracold atomic ensemble we demonstrate a remnant field noise of 2.6 microGauss and a suppression of external dc magnetic fields by more than five orders of magnitude.