Cold atomic beam produced by a conical mirror funnel

We have obtained and characterized a cold atomic beam produced by a simple conical atom funnel, which consists of a conical hollow mirror (axicon) with a small hole at the apex and a single incident laser beam. Atoms trapped in the axicon mirror are ejected by the radiation-pressure imbalance along the extraction column. The atomic beam has a longitudinal velocity in the range of 4 to 6 m/s, a divergence of 150 mrad, and a maximum instantaneous flux of $2.2\ifmmode\times\else\texttimes\fi{}{10}^{10} \mathrm{atoms}/\mathrm{s}$ in a pulsed operation. The experimental results are in quantitative agreement with the numerical simulations. A continuous atomic beam is also possible with an apex hole smaller than the trapped atomic cloud.