Spectral resolution of near-resonant rayleigh scattering and collision-induced resonance fluorescence

) resonance transition was resolved into its three spectral components: Rayleigh scattering, collision-induced fluorescence, and three-photon scattering. The saturation behavior of the central (Rayleigh) component and the intensity and ac Stark shift of the three-photon component were studied as a function of detuning and laser intensity. Good agreement is obtained with theoretical predictions.

Related papers

Spectral Resolution of Near-Resonant Rayleigh Scattering and Collision-Induced Resonance Fluorescence

John L. Carlsten, A. Szöke

Light scattered from strontium vapor near its 460.73-nm ($^{1}{P}_{1}^{\ensuremath{\circ}}\ensuremath{-}^{1}S_{0}$) resonance transition was resolved into its three spectral components: Rayleigh scattering, collision-induced fluorescence, and three-photon scattering. The saturation behavior of the central (Rayleigh) component and the intensity and ac Stark shift of the three-photon component were studied as a function of detuning and laser intensity. Good agreement is obtained with theoretical predictions.Light scattered from strontium vapor near its 460.73-nm ($^{1}{P}_{1}^{\ensuremath{\circ}}\ensuremath{-}^{1}S_{0}$) resonance transition was resolved into its three spectral components: Rayleigh scattering, collision-induced fluorescence, and three-photon scattering. The saturation behavior of the central (Rayleigh) component and the intensity and ac Stark shift of the three-photon component were studied as a function of detuning and laser intensity. Good agreement is obtained with theoretical predictions.

Physical Review LettersMar 22, 197681 citations

Collisional redistribution and saturation of near-resonance scattered light

John L. Carlsten, A. Szöke, Michael G. Raymer

This paper reports on our studies of near-resonant scattering of laser light in a collisional environment. A pulsed dye laser with a peak power of 55 MW/ ${\mathrm{cm}}^{2}$ was tuned near the 460.73-nm resonance line of strontium and the side emission was observed from an oven containing both strontium vapor and argon buffer gas. The emission was composed of three spectral components: Rayleigh scattering at the frequency of the laser ${\ensuremath{\omega}}_{L}$, fluorescence at the resonance frequency ${\ensuremath{\omega}}_{0}$ of strontium, and a third component at $2{\ensuremath{\omega}}_{L}\ensuremath{-}{\ensuremath{\omega}}_{0}$. These three components have been studied as a function of the frequency and intensity of the laser and also as a function of the argon buffer gas pressure. While the Rayleigh emission was found to vary as ${\ensuremath{\Delta}}^{\ensuremath{-}2}$ ($\ensuremath{\Delta}={\ensuremath{\omega}}_{0}\ensuremath{-}{\ensuremath{\omega}}_{L}$), the fluorescence component, which was produced by Sr-Ar collisions, was found to be asymmetric with the sign of $\ensuremath{\Delta}$ as predicted by line-broadening theory. By measuring the ratio of the intensities of the fluorescence and Rayleigh components, we were able to measure directly the collisional redistribution function, important in the study of radiative transfer in stellar and planetary atmospheres. At high laser intensities all three components were found to saturate. The results were compared with the theoretical predictions of Mollow's steady-state theory. Theoretical fits for the high-intensity results were obtained when the collisional cross sections were taken to be considerably smaller than in our low-intensity measurements. We believe the discrepancy lies in the use of a steady-state theory for a transient experiment. Effects of radiative trapping and spatial averaging are also discussed.This paper reports on our studies of near-resonant scattering of laser light in a collisional environment. A pulsed dye laser with a peak power of 55 MW/${\mathrm{cm}}^{2}$ was tuned near the 460.73-nm resonance line of strontium and the side emission was observed from an oven containing both strontium vapor and argon buffer gas. The emission was composed of three spectral components: Rayleigh scattering at the frequency of the laser ${\ensuremath{\omega}}_{L}$, fluorescence at the resonance frequency ${\ensuremath{\omega}}_{0}$ of strontium, and a third component at $2{\ensuremath{\omega}}_{L}\ensuremath{-}{\ensuremath{\omega}}_{0}$. These three components have been studied as a function of the frequency and intensity of the laser and also as a function of the argon buffer gas pressure. While the Rayleigh emission was found to vary as ${\ensuremath{\Delta}}^{\ensuremath{-}2}$ ($\ensuremath{\Delta}={\ensuremath{\omega}}_{0}\ensuremath{-}{\ensuremath{\omega}}_{L}$), the fluorescence component, which was produced by Sr-Ar collisions, was found to be asymmetric with the sign of $\ensuremath{\Delta}$ as predicted by line-broadening theory. By measuring the ratio of the intensities of the fluorescence and Rayleigh components, we were able to measure directly the collisional redistribution function, important in the study of radiative transfer in stellar and planetary atmospheres. At high laser intensities all three components were found to saturate. The results were compared with the theoretical predictions of Mollow's steady-state theory. Theoretical fits for the high-intensity results were obtained when the collisional cross sections were taken to be considerably smaller than in our low-intensity measurements. We believe the discrepancy lies in the use of a steady-state theory for a transient experiment. Effects of radiative trapping and spatial averaging are also discussed.

Physical Review AMar 1, 1977233 citations

Collisional redistribution of near-resonant scattered light in Sr vapour

John L. Carlsten, A. Szöke

Strontium vapour was irradiated by a dye laser tuned near the 460.73 nm ( 1 P 1 0 - 1 S 0 ) resonance transition. Collision-induced fluorescence at the resonance frequency and Rayleigh scattering at the laser frequency were studied as a function of detuning Delta over a range of about 30 nm (1500 cm -1 ). The Rayleigh component was found to vary as Delta -2 , as expected, whereas the collision-induced fluorescence was markedly asymmetric. This experiment constitutes a direct measurement of the redistribution function.Strontium vapour was irradiated by a dye laser tuned near the 460.73 nm ( 1 P 1 0 - 1 S 0 ) resonance transition. Collision-induced fluorescence at the resonance frequency and Rayleigh scattering at the laser frequency were studied as a function of detuning Delta over a range of about 30 nm (1500 cm -1 ). The Rayleigh component was found to vary as Delta -2 , as expected, whereas the collision-induced fluorescence was markedly asymmetric. This experiment constitutes a direct measurement of the redistribution function.

Journal of Physics B Atomic and Molecular PhysicsJun 21, 197639 citations

Two-Photon Near-Resonance Light Scattering from an Atomic Level

J. Liran, L. A. Levin, G. Erez +1 more

We have studied the time-resolved spectra, the energy-resolved spectra, and the total intensity of light emission induced by near-resonance two-photon excitation to the $4^{2}D_{\frac{3}{2}}$ and $4^{2}D_{\frac{5}{2}}$ levels of Na over the detuning range $\ensuremath{-}7 {\mathrm{cm}}^{\ensuremath{-}1}<~\ensuremath{\Delta}<~7 {\mathrm{cm}}^{\ensuremath{-}1}$. The time-resolved spectra of Na perturbed by Ar exhibit a fast adiabatic component and a slow resonance-fluorescence component. The cross section for phase-shifting, ${T}_{2}$ -type collisions in this atomic system is $\ensuremath{\sigma}=110\ifmmode\pm\else\textpm\fi{}20$ ${\mathrm{\AA{}}}^{2}$ .We have studied the time-resolved spectra, the energy-resolved spectra, and the total intensity of light emission induced by near-resonance two-photon excitation to the $4^{2}D_{\frac{3}{2}}$ and $4^{2}D_{\frac{5}{2}}$ levels of Na over the detuning range $\ensuremath{-}7 {\mathrm{cm}}^{\ensuremath{-}1}<~\ensuremath{\Delta}<~7 {\mathrm{cm}}^{\ensuremath{-}1}$. The time-resolved spectra of Na perturbed by Ar exhibit a fast adiabatic component and a slow resonance-fluorescence component. The cross section for phase-shifting, ${T}_{2}$-type collisions in this atomic system is $\ensuremath{\sigma}=110\ifmmode\pm\else\textpm\fi{}20$ ${\mathrm{\AA{}}}^{2}$.

Physical Review LettersFeb 21, 197710 citations

Redistributed spectrum of scattered light

E L Lewis, Daryl Szebesta

The spectrum of redistributed light that results from excitation by monochromatic near-resonant incident light has been observed in calcium perturbed by argon. The two components were found to be well described by the astrophysical redistribution functions ${\mathit{R}}_{\mathrm{II}}$ and ${\mathit{R}}_{\mathrm{III}}$ for the Rayleigh and fluorescent peaks, respectively. The Doppler width of the Rayleigh component was observed to be \ensuremath{\surd}2 larger than that of the fluorescent component, for our observation at right angle to the incident beam, clearly demonstrating the coherence of this part of the scattering. The ratio of fluorescent to Rayleigh intensity was independent of detuning within our range, which was well within the impact region, and increased linearly with argon pressure in a manner that is consistent with an identification of the cross section for redistributing collisions with that for line broadening.The spectrum of redistributed light that results from excitation by monochromatic near-resonant incident light has been observed in calcium perturbed by argon. The two components were found to be well described by the astrophysical redistribution functions ${\mathit{R}}_{\mathrm{II}}$ and ${\mathit{R}}_{\mathrm{III}}$ for the Rayleigh and fluorescent peaks, respectively. The Doppler width of the Rayleigh component was observed to be \ensuremath{\surd}2 larger than that of the fluorescent component, for our observation at right angle to the incident beam, clearly demonstrating the coherence of this part of the scattering. The ratio of fluorescent to Rayleigh intensity was independent of detuning within our range, which was well within the impact region, and increased linearly with argon pressure in a manner that is consistent with an identification of the cross section for redistributing collisions with that for line broadening.

Physical Review AAug 1, 19901 citation

Light scattering on theF= 1 →F′ = 0 transition in a cold and high density87Rb vapor

A. S. Sheremet, Igor M. Sokolov, Dmitriy V. Kupriyanov +3 more

We report an experimental study of near resonance light scattering on the component of the line in atomic . Experiments are performed on spatially bi-Gaussian ultracold gas samples having peak densities ranging from about – atoms/cm and for a range of resonance saturation parameters and detunings from atomic resonance. Time resolution of the scattered light intensity reveals the dynamics of light scattering, optical pumping, and saturation effects. The experimental line shape for optical excitation in steady state is found to be significantly narrower than that for the transition studied previously under similar conditions. This difference is qualitatively reproduced by a theoretical model of the two transitions at similar density.We report an experimental study of near resonance light scattering on the component of the line in atomic . Experiments are performed on spatially bi-Gaussian ultracold gas samples having peak densities ranging from about – atoms/cm and for a range of resonance saturation parameters and detunings from atomic resonance. Time resolution of the scattered light intensity reveals the dynamics of light scattering, optical pumping, and saturation effects. The experimental line shape for optical excitation in steady state is found to be significantly narrower than that for the transition studied previously under similar conditions. This difference is qualitatively reproduced by a theoretical model of the two transitions at similar density.

Journal of Modern OpticsJan 2, 201411 citations

Light scattered from strontium vapor near its 460.73-nm (

^{1}{P}_{1}^{\ensuremath{\circ}}\ensuremath{-}^{1}S_{0}

This paper reports on our studies of near-resonant scattering of laser light in a collisional environment. A pulsed dye laser with a peak power of 55 MW/

{\mathrm{cm}}^{2}

was tuned near the 460.73-nm resonance line of strontium and the side emission was observed from an oven containing both strontium vapor and argon buffer gas. The emission was composed of three spectral components: Rayleigh scattering at the frequency of the laser ${\ensuremath{\omega}}_{L}$, fluorescence at the resonance frequency ${\ensuremath{\omega}}_{0}$ of strontium, and a third component at $2{\ensuremath{\omega}}_{L}\ensuremath{-}{\ensuremath{\omega}}_{0}$. These three components have been studied as a function of the frequency and intensity of the laser and also as a function of the argon buffer gas pressure. While the Rayleigh emission was found to vary as ${\ensuremath{\Delta}}^{\ensuremath{-}2}$ ($\ensuremath{\Delta}={\ensuremath{\omega}}_{0}\ensuremath{-}{\ensuremath{\omega}}_{L}$), the fluorescence component, which was produced by Sr-Ar collisions, was found to be asymmetric with the sign of $\ensuremath{\Delta}$ as predicted by line-broadening theory. By measuring the ratio of the intensities of the fluorescence and Rayleigh components, we were able to measure directly the collisional redistribution function, important in the study of radiative transfer in stellar and planetary atmospheres. At high laser intensities all three components were found to saturate. The results were compared with the theoretical predictions of Mollow's steady-state theory. Theoretical fits for the high-intensity results were obtained when the collisional cross sections were taken to be considerably smaller than in our low-intensity measurements. We believe the discrepancy lies in the use of a steady-state theory for a transient experiment. Effects of radiative trapping and spatial averaging are also discussed.

We have studied the time-resolved spectra, the energy-resolved spectra, and the total intensity of light emission induced by near-resonance two-photon excitation to the

4^{2}D_{\frac{3}{2}}

and

4^{2}D_{\frac{5}{2}}

levels of Na over the detuning range $\ensuremath{-}7 {\mathrm{cm}}^{\ensuremath{-}1}<~\ensuremath{\Delta}<~7 {\mathrm{cm}}^{\ensuremath{-}1}$. The time-resolved spectra of Na perturbed by Ar exhibit a fast adiabatic component and a slow resonance-fluorescence component. The cross section for phase-shifting,

{T}_{2}

-type collisions in this atomic system is $\ensuremath{\sigma}=110\ifmmode\pm\else\textpm\fi{}20$

{\mathrm{\AA{}}}^{2}

{\mathit{R}}_{\mathrm{II}}

and

{\mathit{R}}_{\mathrm{III}}

for the Rayleigh and fluorescent peaks, respectively. The Doppler width of the Rayleigh component was observed to be \ensuremath{\surd}2 larger than that of the fluorescent component, for our observation at right angle to the incident beam, clearly demonstrating the coherence of this part of the scattering. The ratio of fluorescent to Rayleigh intensity was independent of detuning within our range, which was well within the impact region, and increased linearly with argon pressure in a manner that is consistent with an identification of the cross section for redistributing collisions with that for line broadening.