Radiative collimation of atomic beams through two-dimensional cooling of atoms by laser-radiation pressure

Abstract
The transverse cooling of a beam of sodium atoms in an axisymmetric light field formed by a reflecting axicon is studied. It is shown that transverse cooling leads to a decrease in angular divergence (collimation) of the atomic beam. The transverse velocities of the beam are reduced from 5.5 × 102 to 1.6 × 102 cm/sec, which corresponds to the decrease in effective transverse temperature of the beam from T = 42 to T = 3.3 mK. The spatial and velocity distributions of the atomic beam are calculated numerically. It is found that theory and experiment are in good agreement.