Resonance flourescence in atomic coherent systems: spectral features
Abstract
Description
We study resonance flourescence in a four level ladder system and illustrate some novel features due to quantum interference and atomic coherence effects. We find that under three photon resonant conditions, in some region of the parameter space of the rabi frequencies $Ω_1,Ω_2,Ω_3$, emission is dominantly by the level 4 at the line center even though there is an almost equal distribution of populations in all the levels. As one increases $Ω_3$ with $Ω_1 and Ω_2$ held fixed, the four level system 'dynamically collapses' to a two level system. The steady state populations and the the resonance flourescence from all the levels provide adequate evidence to this effect.
15 pages, RevTex including postscript figures. Corrected typos
15 pages, RevTex including postscript figures. Corrected typos