We have used the narrow 2 S 1/2 [arrow right] 3 P 3/2 transition in the ultraviolet (UV) to laser cool and magneto-optically trap (MOT) 6 Li atoms. Laser cooling of lithium atoms is usually performed on the 2 S 1/2 [arrow right] 2 P 3/2 (D2) transition, where temperatures of twice the Doppler limit, or ∼300 μ K for lithium, are achieved. The linewidth of the UV transition is seven times narrower than the D2 line, resulting in a lower Doppler limit. We show that a MOT operating on the UV transition reaches temperatures as low as 59 μ K. We load 6 million atoms from this UV MOT into a 1070 nm optical dipole trap (ODT). We show that the light shift of the UV transition in the ODT is small and blue-shifted, facilitating efficient loading. Evaporative cooling of a two spin-state mixture of 6 Li in the ODT produces a quantum degenerate Fermi gas with 3 million atoms in only 11 seconds.We have used the narrow 2 S 1/2 [arrow right] 3 P 3/2 transition in the ultraviolet (UV) to laser cool and magneto-optically trap (MOT) 6 Li atoms. Laser cooling of lithium atoms is usually performed on the 2 S 1/2 [arrow right] 2 P 3/2 (D2) transition, where temperatures of twice the Doppler limit, or ∼300 μ K for lithium, are achieved. The linewidth of the UV transition is seven times narrower than the D2 line, resulting in a lower Doppler limit. We show that a MOT operating on the UV transition reaches temperatures as low as 59 μ K. We load 6 million atoms from this UV MOT into a 1070 nm optical dipole trap (ODT). We show that the light shift of the UV transition in the ODT is small and blue-shifted, facilitating efficient loading. Evaporative cooling of a two spin-state mixture of 6 Li in the ODT produces a quantum degenerate Fermi gas with 3 million atoms in only 11 seconds.

Jan 1, 20112 citations

The Optical Dipolar Force Trap of Laser Cooling Atoms

翔平藤田

Jul 1, 20140 citations

Sympathetic Cooling with Two Atomic Species in an Optical Trap

Marcel Carto Constantin Mudrich, Stephan Kraft, Kilian Singer +3 more

We simultaneously trap ultracold lithium and cesium atoms in an optical dipole trap formed by the focus of a ${\mathrm{CO}}_{2}$ laser and study the exchange of thermal energy between the gases. The optically cooled cesium gas efficiently decreases the temperature of the lithium gas through sympathetic cooling. Equilibrium temperatures down to $25\ensuremath{\mu}\mathrm{K}$ have been reached. The measured cross section for thermalizing ${}^{133}\mathrm{Cs}{\ensuremath{-}}^{7}\mathrm{Li}$ collisions is $8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}{\mathrm{cm}}^{2}$, for both species unpolarized in their lowest hyperfine ground state. Besides thermalization, we observe evaporation of lithium purely through elastic cesium-lithium collisions (sympathetic evaporation).We simultaneously trap ultracold lithium and cesium atoms in an optical dipole trap formed by the focus of a ${\mathrm{CO}}_{2}$ laser and study the exchange of thermal energy between the gases. The optically cooled cesium gas efficiently decreases the temperature of the lithium gas through sympathetic cooling. Equilibrium temperatures down to $25\ensuremath{\mu}\mathrm{K}$ have been reached. The measured cross section for thermalizing ${}^{133}\mathrm{Cs}{\ensuremath{-}}^{7}\mathrm{Li}$ collisions is $8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}{\mathrm{cm}}^{2}$, for both species unpolarized in their lowest hyperfine ground state. Besides thermalization, we observe evaporation of lithium purely through elastic cesium-lithium collisions (sympathetic evaporation).

arXiv:physics/0111213Physical Review LettersJun 7, 2002139 citations

Transport control of Laser Cooled Atoms Using Optical Dipole Force Trap

夏生一ノ関

Jul 1, 20150 citations

SYMPATHETIC COOLING OF LITHIUM BY LASER-COOLED CESIUM

S. KRAFT, Marcel Carto Constantin Mudrich, K. SINGER +3 more

We present first indications of sympathetic cooling between two neutral, optically trapped atomic species. Lithium and cesium atoms are simultaneously stored in an optical dipole trap formed by the focus of a CO $_2$ laser, and allowed to interact for a given period of time. The temperature of the lithium gas is found to decrease when in thermal contact with cold cesium. The timescale of thermalization yields an estimate for the Li-Cs cross-section.We present first indications of sympathetic cooling between two neutral, optically trapped atomic species. Lithium and cesium atoms are simultaneously stored in an optical dipole trap formed by the focus of a CO$_2$ laser, and allowed to interact for a given period of time. The temperature of the lithium gas is found to decrease when in thermal contact with cold cesium. The timescale of thermalization yields an estimate for the Li-Cs cross-section.

arXiv:physics/0109069Laser SpectroscopyJun 1, 20020 citations

Optical Dipole Traps for Neutral Atoms

Rudolf Grimm, Matthias Weidemüller, Yuri B. Ovchinnikov

Advances in atomic, molecular, and optical physicsJan 1, 20001,549 citations

We simultaneously trap ultracold lithium and cesium atoms in an optical dipole trap formed by the focus of a

{\mathrm{CO}}_{2}

laser and study the exchange of thermal energy between the gases. The optically cooled cesium gas efficiently decreases the temperature of the lithium gas through sympathetic cooling. Equilibrium temperatures down to $25\ensuremath{\mu}\mathrm{K}$ have been reached. The measured cross section for thermalizing ${}^{133}\mathrm{Cs}{\ensuremath{-}}^{7}\mathrm{Li}$ collisions is $8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}{\mathrm{cm}}^{2}$, for both species unpolarized in their lowest hyperfine ground state. Besides thermalization, we observe evaporation of lithium purely through elastic cesium-lithium collisions (sympathetic evaporation).

_2

laser, and allowed to interact for a given period of time. The temperature of the lithium gas is found to decrease when in thermal contact with cold cesium. The timescale of thermalization yields an estimate for the Li-Cs cross-section.