Two-Photon absorption of gas on elastic collisions with walls

V. R. Nagibarov, В. В. Самарцев, Leonid A. Nefediev

V. A. Ulybin, V. P. Chebotaev

Veniamin P. Chebotayev, V. A. Ulybin

Aleksey I. Alekseev, V. N. Beloborodov

A detailed analysis is made of transient coherent Doppler-free spectroscopy of two-photon absorption in an atomic gas. The hyperfine structure of the levels and elastic depolarizing collisions are allowed for. The analysis is used to develop a method for the determination of the time constant of relaxation of the multipole moments of atoms when such relaxation is due to radiative decay and collisions with a buffer gas. A way of determining the separation between the hyperfine structure components is demonstrated. It is shown that under conditions of excitation of the atoms the hyperfine structure of the levels can give rise to quantum beats of the density of a conjugate wave.

M. S. Pindzola

Georgy A. Kazakov, A N Litvinov, B G Matisov +3 more

We studied theoretically a coherent population trapping resonance formation in cylindrical cell without buffer gas irradiated by a narrow laser beam. We take into account non-zero probabilities of elastic ("specular") and inelastic ("sticking") collision between the atom and the cell wall. We have developed a theoretical model based on averaging over the random Ramsey pulse sequences of times that atom spent in and out of the beam. It is shown that the shape of coherent population trapping resonance line depends on the probability of elastic collision.