Detailed study of a transverse field Zeeman slower

TL;DR

This paper provides a detailed analysis of a sodium atom Zeeman slower using permanent magnets, addressing optical leakages and proposing an atomic state preparation method to enhance performance.

Contribution

It introduces an atomic state preparation stage that significantly improves Zeeman slower efficiency, demonstrated through theoretical analysis and experimental validation.

Findings

Magneto-optical trap loading rate increased by 3.5 times

Optical pumping effectively reduces dark state leakages

Method adaptable to various Zeeman slower designs

Abstract

We present a thorough analysis of a Zeeman slower for sodium atoms made of permanent magnets in a Halbach configuration. Due to the orientation of the magnetic field, the polarisation of the slowing laser beam cannot be purely circular leading to optical leakages into dark states. To circumvent this effect, we propose an atomic state preparation stage able to significantly increase the performances of the Zeeman slower. After a careful theoretical analysis of the problem, we experimentally implement an optical pumping stage leading to an increase of the magneto-optical trap loading rate by 3.5. Such method is easy to set up and could be extended to other Zeeman slower architectures.