Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:physics/0202016 · Physical Review Letters

Coherent Light Transport in a Cold Strontium Cloud

Yannick Bidel, Bruce G. Klappauf, J. C. Bernard, Dominique Delande, G. Labeyrie, Christian Miniatura, David Wilkowski, Robin Kaiser

Published May 7, 2002• 102 citations
arXivHTMLPDF

Abstract

We study light coherent transport in the weak localization regime using magneto-optically cooled strontium atoms. The coherent backscattering cone is measured in the four polarization channels using light resonant with a J(g) = 0-->J(e) = 1 transition of the strontium atom. We find an enhancement factor close to 2 in the helicity preserving channel, in agreement with theoretical predictions. This observation confirms the effect of internal structure as the key mechanism for the contrast reduction observed with a rubidium cold cloud [G. Labeyrie et al., Phys. Rev. Lett. 83, 5266 (1999)]. Experimental results are in good agreement with Monte Carlo simulations taking into account geometry effects.

DOI
10.1103/physrevlett.88.203902

Related papers

Coherent backscattering of light from a cold atomic cloud

G. Labeyrie, F. De Tomasi, J.-C. Bernard +3 more

We report the first observation of coherent backscattering of light from a sample of laser-cooled atoms. Rubidium 85 atoms are captured from a room-temperature vapor in a magneto-optical trap, and illuminated with a laser probe. The angular intensity distribution of the backscattered light is recorded on a cooled CCD detector. We observe a small enhancement factor in all polarization channels, including the helicity preserving channel where the enhancement is only 1.08. This surprising observation is attributed to the existence of contrast reduction processes involving the atom's internal structure.

Journal de Physique IV (Proceedings)•May 1, 2000•0 citations

Coherent Backscattering of Light From an Ultra Cold Gas of Rubidium-85 Atoms

P. Kulatunga

This thesis reports on the experimental study of coherent radiative transport in an ultracold gas of 85Rb atoms confined in a magneto-optic trap. Measurements are made of the polarization dependence of the spatial and spectral profile of light backscattered from the sample. The results shows an interferometric enhancement sensitive to coherent multiple scattering in the atomic gas, and strong variations with the polarization of the incident and detected light. Effects due to coherent enhancement of weak non-resonant transitions are also observed. Comparison of the measurements with realistic quantum Monte Carlo simulations of Kupriyanov, et al [1] yield very good agreement.

•Jan 1, 2003•0 citations

Coherent backscattering of light by an inhomogeneous cloud of cold atoms

G. Labeyrie, Dominique Delande, Cord Axel Müller +2 more

When a quasiresonant laser beam illuminates an optically thick cloud of laser-cooled rubidium atoms, the average diffuse intensity reflected off the sample is enhanced in a narrow angular range around the direction of exact backscattering. This phenomenon is known as coherent backscattering (CBS). By detuning the laser from resonance, we are able to modify the light scattering mean-free path inside the sample and we record accordingly the variations of the CBS cone shape. We then compare the experimental data with theoretical calculations and Monte Carlo simulations including the effect of the light polarization and of the internal structure of the atoms. We confirm that the internal structure strongly affects the enhancement factor of the cone and we show that the unusual shape of the atomic medium---approximately a spherically-symmetric, Gaussian density profile---strongly affects the width and shape of the cone.

Physical Review A•Mar 27, 2003•47 citations

Phase coherence in multiple scattering: weak and intense monochromatic light wave propagating in a cold strontium cloud

David Wilkowski, Yannick Bidel, T. Chanelière +3 more

For large bulk disordered media, light transport is generally successfully described by a diffusion process. This picture assumes that any interference is washed out under configuration average. However, it is now known that, under certain circumstances, some interference effects survive the disorder average and in turn lead to wave localizations effects. In this paper, we investigate coherence of a monochromatic laser light propagating in an optically thick sample of laser-cooled strontium atoms. For this purpose, we use the coherent backscattering effect as an interferometric tool. At low laser probe beam intensities, phase coherence is fully preserved and the interference contrast is maximal. At higher intensities, saturation effects start to set in and the interference contrast is reduced.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Aug 1, 2005•2 citations

Coherent backscattering of light by cold atoms: Theory meets experiment

G. Labeyrie, Dominique Delande, Cord Axel Müller +2 more

Coherent backscattering (CBS) of quasi-resonant light by cold atoms presents some specific features due to the internal structure of the atomic scatterers. We present the first quantitative comparison between the experimentally observed CBS cones and Monte Carlo calculations which take into account the shape of the atomic cloud as well as the internal atomic structure.

arXiv:physics/0211091•Europhysics Letters (EPL)•Feb 1, 2003•47 citations

Saturation-induced coherence loss in coherent backscattering of light

T. Chanelière, David Wilkowski, Yannick Bidel +2 more

We use coherent backscattering of light by cold strontium atoms to study phase-breaking mechanisms in the multiple-scattering regime. As the probe light intensity is increased, the atomic optical transition starts to be saturated. Nonlinearities and inelastic scattering then occur. The latter induces a characteristic phase-breaking time that reduces the wave coherence. In our experiment, this leads to a strong reduction of the enhancement factor of the coherent backscattering cone. The results at different probe detuning are also presented.

arXiv:physics/0309095•Physical Review E•Sep 3, 2004•56 citations
We study light coherent transport in the weak localization regime using magneto-optically cooled strontium atoms. The coherent backscattering cone is measured in the four polarization channels using light resonant with a J(g) = 0-->J(e) = 1 transition of the strontium atom. We find an enhancement factor close to 2 in the helicity preserving channel, in agreement with theoretical predictions. This observation confirms the effect of internal structure as the key mechanism for the contrast reduction observed with a rubidium cold cloud [G. Labeyrie et al., Phys. Rev. Lett. 83, 5266 (1999)]. Experimental results are in good agreement with Monte Carlo simulations taking into account geometry effects.
We report the first observation of coherent backscattering of light from a sample of laser-cooled atoms. Rubidium 85 atoms are captured from a room-temperature vapor in a magneto-optical trap, and illuminated with a laser probe. The angular intensity distribution of the backscattered light is recorded on a cooled CCD detector. We observe a small enhancement factor in all polarization channels, including the helicity preserving channel where the enhancement is only 1.08. This surprising observation is attributed to the existence of contrast reduction processes involving the atom's internal structure.
This thesis reports on the experimental study of coherent radiative transport in an ultracold gas of 85Rb atoms confined in a magneto-optic trap. Measurements are made of the polarization dependence of the spatial and spectral profile of light backscattered from the sample. The results shows an interferometric enhancement sensitive to coherent multiple scattering in the atomic gas, and strong variations with the polarization of the incident and detected light. Effects due to coherent enhancement of weak non-resonant transitions are also observed. Comparison of the measurements with realistic quantum Monte Carlo simulations of Kupriyanov, et al [1] yield very good agreement.
When a quasiresonant laser beam illuminates an optically thick cloud of laser-cooled rubidium atoms, the average diffuse intensity reflected off the sample is enhanced in a narrow angular range around the direction of exact backscattering. This phenomenon is known as coherent backscattering (CBS). By detuning the laser from resonance, we are able to modify the light scattering mean-free path inside the sample and we record accordingly the variations of the CBS cone shape. We then compare the experimental data with theoretical calculations and Monte Carlo simulations including the effect of the light polarization and of the internal structure of the atoms. We confirm that the internal structure strongly affects the enhancement factor of the cone and we show that the unusual shape of the atomic medium---approximately a spherically-symmetric, Gaussian density profile---strongly affects the width and shape of the cone.
For large bulk disordered media, light transport is generally successfully described by a diffusion process. This picture assumes that any interference is washed out under configuration average. However, it is now known that, under certain circumstances, some interference effects survive the disorder average and in turn lead to wave localizations effects. In this paper, we investigate coherence of a monochromatic laser light propagating in an optically thick sample of laser-cooled strontium atoms. For this purpose, we use the coherent backscattering effect as an interferometric tool. At low laser probe beam intensities, phase coherence is fully preserved and the interference contrast is maximal. At higher intensities, saturation effects start to set in and the interference contrast is reduced.
We use coherent backscattering of light by cold strontium atoms to study phase-breaking mechanisms in the multiple-scattering regime. As the probe light intensity is increased, the atomic optical transition starts to be saturated. Nonlinearities and inelastic scattering then occur. The latter induces a characteristic phase-breaking time that reduces the wave coherence. In our experiment, this leads to a strong reduction of the enhancement factor of the coherent backscattering cone. The results at different probe detuning are also presented.