Light-Induced Atomic Desorption for loading a Sodium Magneto-Optical Trap

TL;DR

This study investigates light-induced atomic desorption of sodium atoms from glass surfaces to optimize loading a sodium magneto-optical trap, revealing wavelength-dependent desorption and promising conditions for Bose-Einstein condensates.

Contribution

It provides the first detailed analysis of photon-stimulated desorption of sodium for MOT loading, including a simple model and experimental data on desorption rates.

Findings

Desorption rate depends steeply on photon wavelength above 2.6 eV.

Up to 3.7x10^7 sodium atoms were trapped under ultra-high vacuum.

The data supports a model linking desorption rate to MOT loading efficiency.

Abstract

We report studies of photon-stimulated desorption (PSD), also known as light-induced atomic desorption(LIAD), of sodium atoms from a vacuum cell glass surface used for loading a magneto-optical trap (MOT). Fluorescence detection was used to record the trapped atom number and the desorption rate. We observed a steep wavelength dependence of the desorption process above 2.6 eV photon energy, a result significant for estimations of sodium vapor density in the lunar atmosphere. Our data fit well to a simple model for the loading of the MOT dependent only on the sodium desorption rate and residual gas density. Up to 3.7x10^7 Na atoms were confined under ultra-high vacuum conditions, creating promising loading conditions for a vapor cell based atomic Bose-Einstein condensate of sodium.