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

Europhysics Letters (EPL)

Subrecoil Raman Cooling of Cesium Atoms

Jakob Reichel, O. Morice, Guglielmo Maria Tino, Ch Salomon

Published Dec 1, 1994• 33 citations
Publisher

Abstract

We use velocity-selective Raman pulses generated by two diode lasers to cool cesium atoms in 1 dimension to an r.m.s. of 1.2 mm/s. This is about 1/3 of the single-photon recoil velocity v rec = ℏk/M , where ℏk is the photon momentum and M the atom's mass. The corresponding effective temperature is a factor of 9 below the single-photon recoil temperature given by k B T rec /2 = 1/2 Mv rec 2 . Because of the high cesium mass, this temperature is only (23 ± 5) nanokelvin, the lowest 1D kinetic temperature reported to date.

DOI
10.1209/0295-5075/28/7/004

Related papers

Laser Cooling of Cesium Atoms Below 3 μK

Ch Salomon, Jean Dalibard, William D. Phillips +2 more

We have measured the temperature of cesium atoms released from optical molasses. For a wide range of laser intensity and detuning from resonance, the temperature depends only on the intensity-to-detuning ratio. The lowest temperature achieved is (2.5 ± 0.6) μK, which corresponds to an r.m.s. velocity of 12.5 mm/s or 3.6 times the single-photon recoil velocity. This is, to our knowledge, the coldest kinetic temperature ever measured for three-dimensional (3D) cooling.

Europhysics Letters (EPL)•Aug 15, 1990•239 citations

One-dimensional raman cooling of cesium: towards the nanokelvin

Jakob Reichel, O. Morice, Guglielmo Maria Tino +1 more

In an all-diode-laser experiment, cesium atoms in a gas cell are trapped and pre-cooled to approx.5 μK in a magneto-optical trap followed by optical molasses. We were able to cool about 20% of the pre-cooled atoms into a narrow Gaussian velocity distribution with vrms = 1.9 mm/s = vrec/ 2. This corresponds to a one-dimensional temperature of 27 nK. Our Monte Carlo simulations indicate that velocities well below vrec should be attainable in this case as well in less than 40 ms.

European Quantum Electronics Conference (EQEC)•Aug 24, 2005•0 citations

Deeply subrecoil two-dimensional Raman cooling

Vincent Boyer, L. J. Lising, S. L. Rolston +1 more

We report the implementation of a two-dimensional Raman cooling scheme using sequential excitations along the orthogonal axes. Using square pulses, we have cooled a cloud of ultracold cesium atoms down to an rms velocity spread of 0.39(5) recoil velocities, corresponding to an effective transverse temperature of $30\phantom{\rule{0.3em}{0ex}}\mathrm{nK}$ $(0.15{T}_{\mathrm{rec}})$. This technique can be useful to improve cold-atom atomic clocks and is particularly relevant for clocks in microgravity.

arXiv:physics/0404012•Physical Review A•Oct 14, 2004•22 citations

Raman Cooling of Cesium below 3 nK: New Approach Inspired by Lévy Flight Statistics

Jakob Reichel, F. Bardou, Maxime Dahan +4 more

We present a new approach to optimize subrecoil Raman cooling, based on L\'evy flight statistics. It shows that simple time sequences using square pulses can lead to very efficient cooling. We tested the method in a one-dimensional experiment with cesium atoms and obtained temperatures below 3 nK, less than $\frac{1}{70}$ of the single photon recoil temperature.

Physical Review Letters•Dec 18, 1995•107 citations

Laser cooling below the recoil limit by stimulated Raman transitions

Nir Davidson

A technique for cooling atoms in two dimensions to temperatures below the single photon recoil limit k{sub B}T{sub rec} = (hk){sup 2}/2M is demonstrated. This technique combines velocity selection using stimulated Raman transitions and dissipation by spontaneous emission. It is an extension of the one dimensional cooling technique that was demonstrated recently. Experimental results for sodium atoms are presented, and the limits on the minimal cooling temperatures are analyzed. Finally, the possibility of applying the Raman cooling technique to atoms in a dipole trap is discussed.

Bulletin of the American Physical Society•May 1, 1993•0 citations

Laser cooling with Raman transitions

Nir Davidson, H. J. Lee, Mark A. Kasevich +1 more

Sequences of stimulated Raman pulses and optical pumping pulses have been previously used to cool atoms to temperatures below the single photon recoil temperature kbTrec = ℏk2/2m, (m the atomic mass, k the propagation vector of the cooling light) in one-dimension.1

Annual Meeting Optical Society of America•Jan 1, 1993•0 citations
We use velocity-selective Raman pulses generated by two diode lasers to cool cesium atoms in 1 dimension to an r.m.s. of 1.2 mm/s. This is about 1/3 of the single-photon recoil velocity v rec = ℏk/M , where ℏk is the photon momentum and M the atom's mass. The corresponding effective temperature is a factor of 9 below the single-photon recoil temperature given by k B T rec /2 = 1/2 Mv rec 2 . Because of the high cesium mass, this temperature is only (23 ± 5) nanokelvin, the lowest 1D kinetic temperature reported to date.
We report the implementation of a two-dimensional Raman cooling scheme using sequential excitations along the orthogonal axes. Using square pulses, we have cooled a cloud of ultracold cesium atoms down to an rms velocity spread of 0.39(5) recoil velocities, corresponding to an effective transverse temperature of 30nK30\phantom{\rule{0.3em}{0ex}}\mathrm{nK}30nK (0.15Trec)(0.15{T}_{\mathrm{rec}})(0.15Trec​). This technique can be useful to improve cold-atom atomic clocks and is particularly relevant for clocks in microgravity.
We present a new approach to optimize subrecoil Raman cooling, based on L\'evy flight statistics. It shows that simple time sequences using square pulses can lead to very efficient cooling. We tested the method in a one-dimensional experiment with cesium atoms and obtained temperatures below 3 nK, less than 170\frac{1}{70}701​ of the single photon recoil temperature.
A technique for cooling atoms in two dimensions to temperatures below the single photon recoil limit k{sub B}T{sub rec} = (hk){sup 2}/2M is demonstrated. This technique combines velocity selection using stimulated Raman transitions and dissipation by spontaneous emission. It is an extension of the one dimensional cooling technique that was demonstrated recently. Experimental results for sodium atoms are presented, and the limits on the minimal cooling temperatures are analyzed. Finally, the possibility of applying the Raman cooling technique to atoms in a dipole trap is discussed.