Rate Equations for Light‐Induced Drift

Abstract

We present a numerical model aiming a t a realistic description of light-induced drift of multilevel atoms in a buffer gas, specializing to case of Na atoms in a noble gas. The model is based on the optical Bloch equations in which the effect of collisions is inrorporated by introducing Keilson-Storer collision kernels. By marking a connection with kinetic theory all adjustable parameters may be fixed.

Spectral anomalies in light-induced drift in alkali-noble gas mixtures

“…For this reason we are only going to discuss here the LID spectral profile in the Lorentz gas. In order to obtain a realistic description of LID for alkalis Parkhomenko and Shalagin (1986) and Haverkort and Woerdman (1990) chose the four-level description of actual alkali atoms with two fine levels ' P ~D and *P3/2 in the first excited state. In many cases the four-level model of alkali atoms can be approximated by the threelevel one (Atutov et a1 1992).…”

“…Thus, we will start from the three-level model of particles (figure I), where the levels n and 1 correspond to the hyperfine components of the ground state and the level m corresponds to the first excited state. We will neglect the collision transitions between the hyperfine structure components, that is justified for alkali metals in noble buffer gases (Walkup et al 1981, Haverkort andWoerdman 1990). Thereby the conditions for manifestation of the optical pumping effect are created.…”

“…Let us note that the last equation (2.1) for p,i(u) is valid if the coherence between hyperfine components n and 1 is negligible. This approximation corresponds to a moderate laser intensity (Haverkort and Woerdman 1990):…”