A multi-photon magneto-optical trap

TL;DR

This paper introduces a novel multi-photon magneto-optical trap that uses optical forces between excited states, enabling efficient cesium atom cooling and trapping with potential applications in background-free detection and cooling of challenging atomic species.

Contribution

It presents a new MOT configuration utilizing excited-state optical forces, expanding the capabilities of atom trapping techniques.

Findings

Efficient cesium atom cooling and trapping achieved.

Sub-Doppler cooling on both sides of two-photon resonance demonstrated.

Potential for background-free detection and trapping of difficult atomic species.

Abstract

We demonstrate a Magneto-Optical Trap (MOT) configuration which employs optical forces due to light scattering between electronically excited states of the atom. With the standard MOT laser beams propagating along the {\it x}- and {\it y}- directions, the laser beams along the {\it z}-direction are at a different wavelength that couples two sets of {\it excited} states. We demonstrate efficient cooling and trapping of cesium atoms in a vapor cell and sub-Doppler cooling on both the red and blue sides of the two-photon resonance. The technique demonstrated in this work may have applications in background-free detection of trapped atoms, and in assisting laser-cooling and trapping of certain atomic species that require cooling lasers at inconvenient wavelengths.