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

Physical Review A

Observation of cold state-selected cesium molecules formed by stimulated Raman photoassociation

B. Laburthe-Tolra, Cyril Drag, P. Pillet

Published Nov 9, 2001• 51 citations
Publisher

Abstract

We demonstrate the formation of cold ground-state ${\mathrm{Cs}}_{2}$ molecules (presumably in a single well-defined rovibrational level) by stimulated Raman photoassociation (PA) in a Cs vapor cell magneto-optical trap. Autler-Townes measurements allow us to precisely define the experimental conditions. The efficiency of the process is comparable to that of the formation of cold molecules obtained after spontaneous deexcitation of photoassociated molecules. Stimulated Raman PA should provide samples where the molecules are cold not only translationally, but are also in a selected rovibrational level.

DOI
10.1103/physreva.64.061401

Related papers

Formation of cold Cs[sub 2] molecules through photoassociation

A. Fioretti

We report on the formation of translationally cold Cs2 ground-state molecules through photoassociation of laser-cooled cesium atoms in a magneto-optical trap. The cold molecules are obtained after spontaneous decay of photoassociated molecules, and detected after pulsed-laser photoionization into Cs2+ ions. Photoassociation spectra of cesium attractive molecular states below the 6S1/2+6P3/2 dissociation limits are reported, obtained with both ion detection and trap-loss method. A temperature as low as 20−5+15 has been measured for the molecular cloud.

AIP conference proceedings•Jan 1, 2000•7 citations

Formation of Cold Cs2 Molecules through Photoassociation

A. Fioretti, D. Comparat, A. Crubellier +3 more

We have performed photoassociative spectroscopy of cold Cs atoms in a vapor-cell magneto-optical trap, within $10{\mathrm{cm}}^{\ensuremath{-}1}$ below the dissociation limit $6s^{2}S_{1/2}+6p^{2}P_{3/2}$. Our detection method is based on pulsed-laser photoionization of ${\mathrm{Cs}}_{2}$ molecules, selectively detected through a time-of-flight mass spectrometer. Temporal and spatial analysis of ${\mathrm{Cs}}_{2}^{+}$ ions show for the first time the formation of translationally cold ${\mathrm{Cs}}_{2}$ triplet ground state molecules, at a temperature $T\ensuremath{\sim}300\ensuremath{\mu}\mathrm{K}$.

Physical Review Letters•May 18, 1998•545 citations

Translationally cold Cs[sub 2] molecules formation in a magneto-optical trap

A. Fioretti, D. Comparat, Cyril Drag +5 more

We report on the observation of translationally cold Cs2 molecules at temperatures in the 300–70 μK range, produced by the photoassociation of cold Cs atoms in a vapor-cell magneto-optical trap. The detection method is based on pulsed-laser photoionization of Cs2 molecules into Cs2+ ions, selectively detected through a time-of-flight mass spectrometer. This technique, together with the usual trap-loss method, enables us to perform the spectroscopy of the long-range attractive molecular states below the 6s 2S1/2+6p 2P3/2 dissociation limit.

AIP conference proceedings•Jan 1, 1998•0 citations

STIMULATED RAMAN MOLECULE FORMATION IN COLD ALKALI GASES.

Paul S. Julienne, Keith R. Burnett, Y. B. Band +1 more

Photoassociation is a process by which two cold, trapped atoms can be optically excited during a collision to make a vibrational level of an excited electronic state of a molecular dimer. High-resolution photoassociation spectra are now well-known for most alkali dimers. The upper level normally decays by spontaneous emission to a number of final molecular levels, bound and unbound. A laser of a second color can be used to stimulate a transition from the upper level to a particular ground state vibrational level. Such a Raman photoassociation process can be used to form translationally cold molecules in a cold atomic gas or a Bose-Einstein condensate. Coupled channels scattering calculations show that the collisional rate coefficient for coherent production of molecules in specific target states, $> 10^{-10} cm^{3}/s,$ can greatly exceed the rate coefficient for forming products due to excited state spontaneous decay. This implies the feasibility of rapid coherent conversion of atom pairs in a condensate to molecules on a time scale short compared to the trap oscillation time. The untrapped molecules can form a coherent molecular beam. We will examine the prospects for the experimental realization of photoassociative molecule formation in cold alkali gases or condensates.

•Jan 1, 1998•0 citations

Observation of cold ground-state cesium molecules produced in a magneto-optical trap

T. Takekoshi, Brian M. Patterson, R. J. Knize

We have observed translationally cold electronic ground-state cesium dimers produced directly in a magneto-optical trap and also by photoassociation of cold atoms in this trap. These neutral molecules were detected using photoionization and time-of-flight spectroscopy. Initial experiments indicated a cold molecular formation rate of about $600{\mathrm{s}}^{\mathrm{\ensuremath{-}}1},$ with no photoassociation laser present. The measured translational temperature of the neutral cesium dimers was approximately 100 \ensuremath{\mu}K.

Physical Review A•Jan 1, 1999•63 citations

Photoassociative Spectroscopy and Formation of Cold Molecules

P. Pillet, Cyril Drag, B. Laburthe-Tolra +7 more

In the molecular photoassociation process, two free cold atoms absorb one photon by a resonant way, to create an excited molecule in a well defined ro-vibrational state. The photoassociative spectroscopy of alkaline dimers yields accurate determinations for the long-range parts of molecular potential curves correlated to the first s + p asymptote. In contrast to atoms, laser cooling of molecules is very difficult because of the lack of a closed two-level scheme for recycling the population. The molecular photoassociation of cold atoms opens also a promising alternative for the formation of cold ground state molecules. Photoassociation of cold cesium atoms has permitted the first observation of translationally cold ground state molecules. The case of the cesium atom is very favorable because the 0 g - and 1 u purely long-range states below the dissociation limit 6s 1/2 +6p 3/2 present Condon points at intermediate distances. Such configurations offer rather efficient channels for the creation of singlet or triplet ground state Cs 2 molecules after spontaneous decay.

Physica Scripta•Jan 1, 2000•0 citations
We demonstrate the formation of cold ground-state Cs2{\mathrm{Cs}}_{2}Cs2​ molecules (presumably in a single well-defined rovibrational level) by stimulated Raman photoassociation (PA) in a Cs vapor cell magneto-optical trap. Autler-Townes measurements allow us to precisely define the experimental conditions. The efficiency of the process is comparable to that of the formation of cold molecules obtained after spontaneous deexcitation of photoassociated molecules. Stimulated Raman PA should provide samples where the molecules are cold not only translationally, but are also in a selected rovibrational level.
We report on the formation of translationally cold Cs2 ground-state molecules through photoassociation of laser-cooled cesium atoms in a magneto-optical trap. The cold molecules are obtained after spontaneous decay of photoassociated molecules, and detected after pulsed-laser photoionization into Cs2+ ions. Photoassociation spectra of cesium attractive molecular states below the 6S1/2+6P3/2 dissociation limits are reported, obtained with both ion detection and trap-loss method. A temperature as low as 20−5+15 has been measured for the molecular cloud.
We have performed photoassociative spectroscopy of cold Cs atoms in a vapor-cell magneto-optical trap, within $10{\mathrm{cm}}^{\ensuremath{-}1}$ below the dissociation limit 6s2S1/2+6p2P3/26s^{2}S_{1/2}+6p^{2}P_{3/2}6s2S1/2​+6p2P3/2​. Our detection method is based on pulsed-laser photoionization of Cs2{\mathrm{Cs}}_{2}Cs2​ molecules, selectively detected through a time-of-flight mass spectrometer. Temporal and spatial analysis of Cs2+{\mathrm{Cs}}_{2}^{+}Cs2+​ ions show for the first time the formation of translationally cold Cs2{\mathrm{Cs}}_{2}Cs2​ triplet ground state molecules, at a temperature $T\ensuremath{\sim}300\ensuremath{\mu}\mathrm{K}$.
We report on the observation of translationally cold Cs2 molecules at temperatures in the 300–70 μK range, produced by the photoassociation of cold Cs atoms in a vapor-cell magneto-optical trap. The detection method is based on pulsed-laser photoionization of Cs2 molecules into Cs2+ ions, selectively detected through a time-of-flight mass spectrometer. This technique, together with the usual trap-loss method, enables us to perform the spectroscopy of the long-range attractive molecular states below the 6s 2S1/2+6p 2P3/2 dissociation limit.
Photoassociation is a process by which two cold, trapped atoms can be optically excited during a collision to make a vibrational level of an excited electronic state of a molecular dimer. High-resolution photoassociation spectra are now well-known for most alkali dimers. The upper level normally decays by spontaneous emission to a number of final molecular levels, bound and unbound. A laser of a second color can be used to stimulate a transition from the upper level to a particular ground state vibrational level. Such a Raman photoassociation process can be used to form translationally cold molecules in a cold atomic gas or a Bose-Einstein condensate. Coupled channels scattering calculations show that the collisional rate coefficient for coherent production of molecules in specific target states, >10−10cm3/s,> 10^{-10} cm^{3}/s,>10−10cm3/s, can greatly exceed the rate coefficient for forming products due to excited state spontaneous decay. This implies the feasibility of rapid coherent conversion of atom pairs in a condensate to molecules on a time scale short compared to the trap oscillation time. The untrapped molecules can form a coherent molecular beam. We will examine the prospects for the experimental realization of photoassociative molecule formation in cold alkali gases or condensates.
We have observed translationally cold electronic ground-state cesium dimers produced directly in a magneto-optical trap and also by photoassociation of cold atoms in this trap. These neutral molecules were detected using photoionization and time-of-flight spectroscopy. Initial experiments indicated a cold molecular formation rate of about $600{\mathrm{s}}^{\mathrm{\ensuremath{-}}1},$ with no photoassociation laser present. The measured translational temperature of the neutral cesium dimers was approximately 100 \ensuremath{\mu}K.
In the molecular photoassociation process, two free cold atoms absorb one photon by a resonant way, to create an excited molecule in a well defined ro-vibrational state. The photoassociative spectroscopy of alkaline dimers yields accurate determinations for the long-range parts of molecular potential curves correlated to the first s + p asymptote. In contrast to atoms, laser cooling of molecules is very difficult because of the lack of a closed two-level scheme for recycling the population. The molecular photoassociation of cold atoms opens also a promising alternative for the formation of cold ground state molecules. Photoassociation of cold cesium atoms has permitted the first observation of translationally cold ground state molecules. The case of the cesium atom is very favorable because the 0 g - and 1 u purely long-range states below the dissociation limit 6s 1/2 +6p 3/2 present Condon points at intermediate distances. Such configurations offer rather efficient channels for the creation of singlet or triplet ground state Cs 2 molecules after spontaneous decay.