Abstract Our work is based on the collision-induced coherence of two decay channels along two optical transitions. The quantum interference of pumping processes creates the dark state and the more atoms are pumped in this collision-induced dark state, the stronger the suppression of the spontaneous emission. The efficiency of this suppression is quantified by putting it in comparison with the spontaneous emission on the ultraviolet transition, which proceeds in a regular fashion. The branching ratio of these two (visible and ultraviolet) transitions is introduced as the effective measure of the degree of the suppression of the spontaneous emission on the visible transition. Our preliminary calculations show that a significant decrease of the branching ratio with an increase of electron densities is reproduced in the theory.Abstract Our work is based on the collision-induced coherence of two decay channels along two optical transitions. The quantum interference of pumping processes creates the dark state and the more atoms are pumped in this collision-induced dark state, the stronger the suppression of the spontaneous emission. The efficiency of this suppression is quantified by putting it in comparison with the spontaneous emission on the ultraviolet transition, which proceeds in a regular fashion. The branching ratio of these two (visible and ultraviolet) transitions is introduced as the effective measure of the degree of the suppression of the spontaneous emission on the visible transition. Our preliminary calculations show that a significant decrease of the branching ratio with an increase of electron densities is reproduced in the theory.

arXiv:1209.4709Laser PhysicsJan 18, 20190 citations

Electronic excitation by atomic collisions

R. Dueren

Dec 1, 19750 citations

Observation of Radiative Collisional Fluorescence

J. C. White, G. Zdasiuk, J. F. Young +1 more

We report the observation of spontaneous radiative emission during the collision of two excited Ba atoms. The emission occurs at the sum energy of the excited atoms and is the emission analog of the laser-induced inelastic collision process. We measure a collision cross section for deexcitation by spontaneous radiative emission of 2.6\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}20}$ ${\mathrm{cm}}^{2}$ .We report the observation of spontaneous radiative emission during the collision of two excited Ba atoms. The emission occurs at the sum energy of the excited atoms and is the emission analog of the laser-induced inelastic collision process. We measure a collision cross section for deexcitation by spontaneous radiative emission of 2.6\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}20}$ ${\mathrm{cm}}^{2}$.

Physical Review LettersDec 18, 197823 citations

SOME NEW PERSPECTIVES IN BREMSSTRAHLUNG RESEARCH

A. Maquet, Alain Dubois, Valérie Vëniard

We report the results of new theoretical calculations of the transition amplitudes and cross-sections for two distinct bremsstrahlung-related processes : i) Stimulated one-photon transitions (Free-Free Transitions) occuning in the course of electron-H atom collisions, in the presence of a strong extemal field. ii) Two-photon Bremsstrahlung, corresponding to the spontaneous emission of two distinct photons in a single electron-atom collision event. The main features of these processes will be outlined and discussed.We report the results of new theoretical calculations of the transition amplitudes and cross-sections for two distinct bremsstrahlung-related processes : i) Stimulated one-photon transitions (Free-Free Transitions) occuning in the course of electron-H atom collisions, in the presence of a strong extemal field. ii) Two-photon Bremsstrahlung, corresponding to the spontaneous emission of two distinct photons in a single electron-atom collision event. The main features of these processes will be outlined and discussed.

Le Journal de Physique ColloquesDec 1, 19870 citations

Spontaneous emission from a tunneling atom

Daniel Braun, John Martin

Bulletin of the American Physical SocietyMar 13, 20080 citations

{\mathrm{cm}}^{2}