The influence of momentum diffusion on laser cooling of atoms

Abstract

Abstract.We show that laser cooling by coherent population trapping in case of zero radiation force -when atomic evolution is due to only momentum diffusion can be effectively described by use of the Fokker-Planck equation for the atomic distribution function. Our quasiclassical approach allows numerically and analytically to investigate the dynamics and the efficiency of the cooling process. It is shown that both the evolution of the momentum distribution and the limit of the cooling are determined by the degree of incompleteness of coherent population trapping.

VSCPT subrecoil laser cooling of atoms with a non-degenerated (J=0) ground state

“…[14]. This technique is based on matching of the solution in the inner region, where substantially a quantum treatment of the atomic translational motion is needed, with the solution in the outer region, where the quasi-classical (Fokker-Planck equation) approach [13] is valid. The analytical solution for t → ∞ demonstrates in an apparent way the advantages of the double cascade scheme.…”

Quasiclassical analysis of laser cooling by velocity-selective coherent population trapping

“…The value of time t* and the minimal value of width 5p;"are found from the analytical solution of FPE (3.3), which will be presented elsewhere [16]: 0.12-t"= f),'/(4g~~y'r ), 5p;"=MA(I /2y)'~/2k .…”