THE INFLUENCE OF MOMENTUM DIFFUSION ON LASER COOLING OF ATOMS

We show that laser cooling by coherent population trapping in case of zero radiation force - when atomic evolution is due to only momentum d iffusion - can be effectively described by use of the Fokker-Planck eq uation for the atomic distribution function. Our quasiclassical approa ch allows numerically and analytically to investigate the dynamics and the efficiency of the cooling process. It is shown that both the evol ution of the momentum distribution and the limit of the cooling are de termined by the degree of incompleteness of coherent population trappi ng.