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

Acta Physica Sinica (Overseas Edition)

Experimental study on laser cooling of cesium atoms by optical molasses

Jidong Hou, LI Yi-min, Donghai Yang, Yiqiu Wang

Published Dec 1, 1998• 2 citations
Publisher

Abstract

We have studied the relationship between the temperature of Cs cold atoms and the parameters of the cooling laser. The atoms are first cooled and captured by a magneto-optical trap and then further cooled by optical molasses. The temperature of atoms is measured by a time-of-flight method. For relatively large laser intensity and small detuning, the temperature depends linearly on the intensity-to-detuning ratio, and nonlinear relationship has also been found in other case.

DOI
10.1088/1004-423x/7/12/001

Related papers

Obtaining Ultra-cold Atoms by Optical Molasses Directly from Vapor

Jidong Hou

Usually the magneto\|optical trap(MOT)is used to obtain the cold atoms from the vapor.It is reported that experiments for obtaining the ultra\|cold cesium atoms by optical molasses directly from the vapor cell without MOT.The lowest temperature achieved for the cesium atomic cloud was 3?μK.The relationship between the temperature and the detuning of cooling laser was measured.

Acta Scicentiarum Naturalum Universitis Pekinesis•Jan 1, 2001•1 citation

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

Laser cooling of cesium atoms below 3 microkelvins

Christophe 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 rms 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. We then discuss the possibility of using such a cold sample of atoms for realizing a high performance atomic clock in a fountain geometry. In particular, a method for launching the atoms upwards, while maintaining the very cold temperature, is demonstrated.

AIP conference proceedings•Jan 1, 1991•5 citations

Parameter Dependence of the Temperature of Cold Cesium Atoms in 3D Near-Resonance Optical Lattice

Junmin Wang

The four-beam 3D near-resonance optical lattice is introduced and experimentally realized based on the magneto-optical trap and optical molasses.The temperature of cold cesium atoms loaded into the lattice is measured via the short-distance time of flight(TOF) absorption spectrum.By changing the intensity and detuning of lattice beams,the lowest temperature in that case is obtained.The parameter dependence of the temperature of the cold atoms in lattice is experimentally investigated,and a comparison with the case of optical molasses is briefly discussed.

Acta Sinica Quantum Optica•Jan 1, 2007•0 citations

Enhanced optical molasses cooling for Cs atoms with largely detuned cooling lasers*

Di Zhang, Yuqing Li, Yunfei Wang +7 more

We report a detailed study of the enhanced optical molasses cooling of Cs atoms, whose large hyperfine structure allows to use the largely red-detuned cooling lasers. We find that the combination of a large frequency detuning of about −110 MHz for the cooling laser and a suitable control for the powers of the cooling and repumping lasers allows to reach a cold temperature of ∼ 5.5 μK. We obtain 5.1× 107 atoms with the number density around 1× 1012 cm−3. Our result gains a lower temperature than that got in other experiments, in which the cold Cs atoms with the temperature of ∼ 10 μK have been achieved by the optical molasses cooling.

Chinese Physics B•Dec 9, 2019•4 citations

Optical Molasses: The Coldest Atoms Ever

William D. Phillips, Paul D. Lett, S. L. Rolston +7 more

Optical molasses is a three-dimensional (3-D) configuration of laser beams used to laser-cool and to viscously confine neutral atoms. Atoms laser cooled in optical molasses reach temperatures much lower than the limit given by the original theories of laser cooling based on the Doppler effect. This cooling below the Doppler-cooling limit is now seen as being due to new laser cooling mechanisms not considered in the original theories. The dependence of the atomic temperature on parameters such as laser intensity and detuning shows good agreement between calculations performed in 1-D and experiments performed in 3-D. For cooling of Na and Cs atoms, the lowest observed temperatures correspond to rms velocities between three and four times the single photon recoil velocity. For Cs the temperature is 2.5 ± 0.6 μK and is the lowest temperature ever measured for 3-D cooling.

Physica Scripta•Jan 1, 1991•6 citations
We have studied the relationship between the temperature of Cs cold atoms and the parameters of the cooling laser. The atoms are first cooled and captured by a magneto-optical trap and then further cooled by optical molasses. The temperature of atoms is measured by a time-of-flight method. For relatively large laser intensity and small detuning, the temperature depends linearly on the intensity-to-detuning ratio, and nonlinear relationship has also been found in other case.
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 rms 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. We then discuss the possibility of using such a cold sample of atoms for realizing a high performance atomic clock in a fountain geometry. In particular, a method for launching the atoms upwards, while maintaining the very cold temperature, is demonstrated.
The four-beam 3D near-resonance optical lattice is introduced and experimentally realized based on the magneto-optical trap and optical molasses.The temperature of cold cesium atoms loaded into the lattice is measured via the short-distance time of flight(TOF) absorption spectrum.By changing the intensity and detuning of lattice beams,the lowest temperature in that case is obtained.The parameter dependence of the temperature of the cold atoms in lattice is experimentally investigated,and a comparison with the case of optical molasses is briefly discussed.
We report a detailed study of the enhanced optical molasses cooling of Cs atoms, whose large hyperfine structure allows to use the largely red-detuned cooling lasers. We find that the combination of a large frequency detuning of about −110 MHz for the cooling laser and a suitable control for the powers of the cooling and repumping lasers allows to reach a cold temperature of ∼ 5.5 μK. We obtain 5.1× 107 atoms with the number density around 1× 1012 cm−3. Our result gains a lower temperature than that got in other experiments, in which the cold Cs atoms with the temperature of ∼ 10 μK have been achieved by the optical molasses cooling.
Optical molasses is a three-dimensional (3-D) configuration of laser beams used to laser-cool and to viscously confine neutral atoms. Atoms laser cooled in optical molasses reach temperatures much lower than the limit given by the original theories of laser cooling based on the Doppler effect. This cooling below the Doppler-cooling limit is now seen as being due to new laser cooling mechanisms not considered in the original theories. The dependence of the atomic temperature on parameters such as laser intensity and detuning shows good agreement between calculations performed in 1-D and experiments performed in 3-D. For cooling of Na and Cs atoms, the lowest observed temperatures correspond to rms velocities between three and four times the single photon recoil velocity. For Cs the temperature is 2.5 ± 0.6 μK and is the lowest temperature ever measured for 3-D cooling.