Influence of collision processes on saturated absorption line shapes

Dietrich Kühlke

J. Mlynek, Rudolf Grimm

J. L. Hall

P. R. Berman, P. F. Liao, John E. Bjorkholm

A theory of saturation spectroscopy in three-level gas-vapor systems, including collisional effects, is presented. Using a model of collisions in which they are phase interrupting in their effect on level coherences and velocity changing in their effect on level population densities, the authors calculate the absorption profile of a weak probe field on a given transition when an arbitrarily strong pump field acts on a coupled transition. Line shapes are derived for an arbitrary collision kernel describing the velocity-changing collisions, and these line shapes are evaluated for the collision kernel proposed by Keilson and Storer. Various limiting forms for the line shapes are derived and representative line shapes are displayed. Several new features of the line shapes, including collisionally induced increased probe absorption are discussed. The line shapes are seen to reflect the various collisional processes that may occur in atomic or molecular systems.

Sergei I Yakovlenko

Im Tkhek-De, Victor P. Kochanov, Sergei G Rautian +2 more

An investigation was made of the absorption of a weak laser wave in the presence of an opposite wave causing saturation. The contribution to the line width due to the atom-atom and atom-electron collisions was determined. The influence of the discharge current and pressure on the ratio of the homogeneous and inhomogeneous components of the saturation was established. Theoretical models were used to explain the experimental results.