Enhanced Raman sideband cooling of caesium atoms in a vapour-loaded magneto-optical trap

TL;DR

This paper demonstrates an improved three-dimensional Raman sideband cooling method for caesium atoms in a vapour-loaded magneto-optical trap, achieving lower temperatures and higher atom numbers efficiently.

Contribution

It introduces a novel cooling scheme with a separate repumping laser and optimized lattice detuning, enhancing atom cooling and loading efficiency in a single-cell system.

Findings

Atoms cooled from 60 μK to 1.7 μK within 12 ms

Loaded 1.2 × 10^7 atoms into the lattice

Theoretical model agrees well with experimental data

Abstract

We report enhanced three-dimensional degenerated Raman sideband cooling (3D DRSC) of caesium (Cs) atoms in a standard single-cell vapour-loading magneto-optical trap. Our improved scheme involves using a separate repumping laser and optimized lattice detuning. We load $1.5 \times 10^7$ atoms into the Raman lattice with a detuning of -15.5 GHz (to the ground F = 3 state). Enhanced 3D DRSC is used to cool them from 60 $\mu$K to 1.7 $\mu$K within 12 ms and the number of obtained atoms is about $1.2 \times 10^7$. A theoretical model is proposed to simulate the measured number of trapped atoms. The result shows good agreement with the experimental data. The technique paves the way for loading a large number of ultracold Cs atoms into a crossed dipole trap and efficient evaporative cooling in a single-cell system.