Theoretical Calculations of the Diffusion and Friction Coefficients for Neutral Atoms that Moving in a Laser Field

This research aimed to study the friction and diffusion coefficients of neutral atoms that moving and interact with a laser field .The Mathcad 14 program used to calculate the results. The theoretical model was solved and shown the effect of different optical parameters on the diffusion and friction of neutral atoms .The different values of ellipticity (Ɛ) were used to find the friction and diffusion coefficients ,for each value of ellipticity we found that the relationship between the natural width of excited level( γ) and the difference(δ) between the frequency of laser field(ω) and the atomic resonance (ω 0 ) has strong effect on the friction coefficient of atoms .The effect of Rabi frequency (Ω ) on the diffusion coefficient has been investigated .In this research the results showed that each of the parameters δ and Ω has effect on the diffusion of atom and the Rabi frequency has more influence. The dependence of the friction and diffusion coefficients on the natural width of the excited level was studied. The measuring of the friction and diffusion coefficients of atom very important to control the movement and then localize it, this have many applications in physics fields.