Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Fluorescence and absorption properties of a driven lambda-system

Igor Bargatin, B. A. Grishanin, Victor N. Zadkov

Published Feb 25, 1999• 1 citation

Abstract

Our investigation is focused on obtaining analytical results describing the resonance fluorescence and weak probe absorption spectra of a driver Lambda-system under the Raman resonance condition. For the saturation field limit and within the rotating wave approximation (RWA) the resonance fluorescence and weak probe absorption spectra are calculated for the case of unequal driving fields strengths and non-zero one-photon detunings, generalizing the previously known results. A novel contribution derived is the nonpositive nonlorentzian part of the spectrum, originating from the specific quantum properties of the atomic correlation functions. This contribution is asymptotically small under given conditions and, therefore, determines behavior of the resonance fluorescence spectrum wings and the absorption spectrum in the vicinities of the driving field frequencies. Beyond the RWA, the spectral structures due to the off-resonant four-photon atomic excitations are calculated. They consist of a coherent and two broadened spectral lines centered at the four-photon frequencies 2(omega) L-(omega) 1L and 2(omega) +1)/ - (omega) L4/ respectively, where (omega l and (omega) (superscript 1$L are the driving laser frequencies.

DOI: 10.1117/12.340122

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