Intense source of cold Rb atoms from a pure two-dimensional magneto-optical trap

Abstract

We present a two-dimensional (2D) magneto-optical trap (MOT) setup for the production of a continuous collimated beam of cold ${}^{87}\mathrm{Rb}$ atoms out of a vapor cell. The underlying physics is purely two-dimensional cooling and trapping, which allows for a high flux of up to $6\ifmmode\times\else\texttimes\fi{}{10}^{10}$ atoms/s and a small divergence of the resulting beam. We analyze the velocity distribution of the 2D MOT. The longitudinal velocity distribution of the atomic beam shows a broad feature (full width at half maximum $\ensuremath{\simeq}75 \mathrm{m}/\mathrm{s}),$ centered around 50 m/s. The dependence of the flux on laser intensity, on geometry of the trapping volume, and on pressure in the vapor cell was investigated in detail. The influence of the geometry of the 2D MOT on the mean velocity of the cold beam has been studied. We present a simple model for the velocity distribution of the flux based on rate equations describing the general features of our source.