Experiments on nonlinear radiation trapping in a saturable atomic vapor - art. no. 043409

Citation
T. Scholz et al., Experiments on nonlinear radiation trapping in a saturable atomic vapor - art. no. 043409, PHYS REV A, 6404(4), 2001, pp. 3409
Citations number
33
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW A
ISSN journal
1050-2947 → ACNP
Volume
6404
Issue
4
Year of publication
2001
Database
ISI
SICI code
1050-2947(200110)6404:4<3409:EONRTI>2.0.ZU;2-E
Abstract
We present experiments of a laser with variable pulse energy and beam width saturating sodium vapor near the D-1-line transition. At high optical dept h and in a buffer gas atmosphere of argon, the effect of nonlinear radiatio n trapping is shown to drastically change the spatial distribution and temp oral evolution of the excited-state population and of the fluorescence ligh t trapped by the nonlinear medium. Besides observing the transient behavior of the fluorescence light, a pump-probe beam experiment enables us to gain a tomographic view inside the atomic vapor. Nitrogen as a buffer gas is us ed to compare with the situation where radiation trapping effects are negli gible. Finally, numerical simulations based upon equations of radiative tra nsfer for a two-level atomic system elucidate the role of nonlinear radiati on trapping and support given interpretations of the experiments.