Raman scattering in an atomic gas in the presence of depolarizing collisions

Gerard Nienhuis, F. Schuller

Aleksey I. Alekseev, O. V. Zhemerdeev

Vitalii D Ovsiannikov

A. I. Alekseev, V N Beloborodov, O. V. Zhemerdeev

A theoretical investigation of the non-stationary Raman scattering (RS) of light in gas atoms with no nuclear spin has been made. Account was taken of the level degeneracy due to the different orientation of the total angular momenta, the dependence of the RS signal on the polarisations of the light pulses and of the elastic depolarising collisions. Interesting RS polarisation properties have been found and assumed as a basis method for the identification of optically forbidden transitions and for the determination of parameters of the cubic susceptibility tensor. It has been proved that the polarisation properties and damping law of the non-stationary RS signal permit multipole relaxation rates of forbidden and allowed atomic transitions to be determined.

A. I. Alekseev, V. N. Beloborodov

Non-stationary two-photon absorption coherent spectroscopy free of Doppler broadening in an atomic gas has been considered in detail. Correct account has been taken of the level degeneracy and depolarizing collisions. This two-photon Doppler-free spectroscopy has been developed for determining the relaxation rates of the atomic multipole moments in gas. A criterion to test the adopted model of the depolarizing collisions has been developed. A possible method for the identification of the atomic transitions in the angular momentum has been formulated. A technique of precisely determining the separation between the energy levels of the two-photon transition has been proposed. The conditions under which the Stokes wave is conjugated with respect to the probe pulse in amplitude, phase and polarization have been determined for the atomic gas in the presence of depolarizing collisions.

M. Ya. Agre, Л. П. Рапопорт