Increased Power and Detuning of Diode Lasers for Magneto-optical Trap of Lithium

This study is aimed at obtaining high concentration of optically cooled lithium-7 atoms for preparing strongly interacting ultracold plasma and Rydberg matter. A special setup has been constructed, in which two high-power semiconductor lasers are used to cool lithium-7 atoms in a magneto-optical trap. At an optimum detuning of the cooling laser frequency and a magnetic field gradient of 35 G/cm, the concentration of ultracold lithium-7 atoms reaches about 10 11 cm −3 . Additional independent information about the concentration and number of ultracold lithium-7 atoms on different sublevels of the ground state was obtained by using of an additional probing laser.This study is aimed at obtaining high concentration of optically cooled lithium-7 atoms for preparing strongly interacting ultracold plasma and Rydberg matter. A special setup has been constructed, in which two high-power semiconductor lasers are used to cool lithium-7 atoms in a magneto-optical trap. At an optimum detuning of the cooling laser frequency and a magnetic field gradient of 35 G/cm, the concentration of ultracold lithium-7 atoms reaches about 10 11 cm −3 . Additional independent information about the concentration and number of ultracold lithium-7 atoms on different sublevels of the ground state was obtained by using of an additional probing laser.

Journal of Experimental and Theoretical PhysicsNov 1, 201414 citations

Efficient magneto-optical trapping of Yb atoms with a violet laser diode

Chang Yong Park, Tai Hyun Yoon

We report an efficient trapping of rare-earth-metal Yb atoms with a high-power violet laser diode (LD). An injection-locked violet LD with a 25-mW frequency-stabilized output was used for the magneto-optical trapping (MOT) of fermionic as well as bosonic Yb isotopes. A typical number of $4\ifmmode\times\else\texttimes\fi{}{10}^{6}$ atoms for ${}^{174}\mathrm{Yb}$ with a trap density of $\ensuremath{\sim}1\ifmmode\times\else\texttimes\fi{}{10}^{8}{\mathrm{cm}}^{\ensuremath{-}3}$ was obtained. A 10-mW violet external-cavity LD was used for the one-dimensional slowing of an effusive Yb atomic beam without a Zeeman slower resulting in a 35-fold increase in the number of trapped atoms. The overall characteristics of our compact violet MOT, e.g., the loss time of 1 s, the loading time of 400 ms, and the cloud temperature of 0.7 mK, are comparable to those in previously reported violet Yb MOTs, yet with a greatly reduced cost and complexity of the experiment.We report an efficient trapping of rare-earth-metal Yb atoms with a high-power violet laser diode (LD). An injection-locked violet LD with a 25-mW frequency-stabilized output was used for the magneto-optical trapping (MOT) of fermionic as well as bosonic Yb isotopes. A typical number of $4\ifmmode\times\else\texttimes\fi{}{10}^{6}$ atoms for ${}^{174}\mathrm{Yb}$ with a trap density of $\ensuremath{\sim}1\ifmmode\times\else\texttimes\fi{}{10}^{8}{\mathrm{cm}}^{\ensuremath{-}3}$ was obtained. A 10-mW violet external-cavity LD was used for the one-dimensional slowing of an effusive Yb atomic beam without a Zeeman slower resulting in a 35-fold increase in the number of trapped atoms. The overall characteristics of our compact violet MOT, e.g., the loss time of 1 s, the loading time of 400 ms, and the cloud temperature of 0.7 mK, are comparable to those in previously reported violet Yb MOTs, yet with a greatly reduced cost and complexity of the experiment.

arXiv:physics/0309034Physical Review ANov 11, 200349 citations

Lithium in a Magneto-Optical Trap

Dan Klemme, Chad Hoyt

Bulletin of the American Physical SocietyFeb 27, 20121 citation

Simultaneous magneto-optical trapping of Ytterbium and Caesium

R. Freytag

This thesis presents progress toward the production of ultracold CsYb molecules. To this end, an apparatus capable of producing magneto optical traps of Yb and Cs was designed, built and tested. Both atoms are produced in a dual species oven and both slowed to low speeds by a single Zeeman slower. From the Zeeman slower atoms are captured in a dual-species magneto-optical trap. To cool caesium the 852 nm D2 transition is addressed by two lasers for cooling and repump. For ytterbium the 399 nm 1S0 ⇒ 1P1 transition is addressed for the Zeeman slower and the 556 nm 1S0 ⇒ 3P1 transition is addressed for the magneto-optical trap. The 399 nm light is produced by two homebuilt diode lasers in an injection-seeding setup, which can produce up to 100 mW. The 556 nm light is produced from a commercial frequency doubled fiber laser, which can produce up to 260 mW. The Zeeman slower is characterised experimentally for both Cs and Yb, and the results compared to those of a numerical simulation of the slower for Yb. The velocity distribution exiting the slower is very sensitive to the exact magnetic field profile, the laser power and detuning of the laser light. The number of atoms loaded into the magneto-optical trap was investigated as a function of the magnetic field gradient, the laser power and the laser detuning. The capture velocity of the Yb MOT is small because the linewidth of the MOT transition is narrow, and so we investigated the influence of broadening the laser linewidth by adding multiple finely-spaced sidebands to the laser light. After optimisation the caesium MOT trapped 5.5 ×10^8 atoms at 125 ± 4 μK. The ytterbium MOT trapped 4.7 ×10^9 atoms at 81 ± 2 μK. Lastly we demonstrate that both MOTs can be produced in the same vacuum chamber simultaneously.This thesis presents progress toward the production of ultracold CsYb molecules. To this end, an apparatus capable of producing magneto optical traps of Yb and Cs was designed, built and tested. Both atoms are produced in a dual species oven and both slowed to low speeds by a single Zeeman slower. From the Zeeman slower atoms are captured in a dual-species magneto-optical trap. To cool caesium the 852 nm D2 transition is addressed by two lasers for cooling and repump. For ytterbium the 399 nm 1S0 ⇒ 1P1 transition is addressed for the Zeeman slower and the 556 nm 1S0 ⇒ 3P1 transition is addressed for the magneto-optical trap. The 399 nm light is produced by two homebuilt diode lasers in an injection-seeding setup, which can produce up to 100 mW. The 556 nm light is produced from a commercial frequency doubled fiber laser, which can produce up to 260 mW. The Zeeman slower is characterised experimentally for both Cs and Yb, and the results compared to those of a numerical simulation of the slower for Yb. The velocity distribution exiting the slower is very sensitive to the exact magnetic field profile, the laser power and detuning of the laser light. The number of atoms loaded into the magneto-optical trap was investigated as a function of the magnetic field gradient, the laser power and the laser detuning. The capture velocity of the Yb MOT is small because the linewidth of the MOT transition is narrow, and so we investigated the influence of broadening the laser linewidth by adding multiple finely-spaced sidebands to the laser light. After optimisation the caesium MOT trapped 5.5 ×10^8 atoms at 125 ± 4 μK. The ytterbium MOT trapped 4.7 ×10^9 atoms at 81 ± 2 μK. Lastly we demonstrate that both MOTs can be produced in the same vacuum chamber simultaneously.

May 1, 20152 citations

Tuning and Locking a Diode Laser for a Magneto-Optical Trap

Rachel Livingston, Matthew Gift, J. H. Huckans +1 more

Bulletin of the American Physical SocietyOct 4, 20140 citations

{}^{174}\mathrm{Yb}

with a trap density of $\ensuremath{\sim}1\ifmmode\times\else\texttimes\fi{}{10}^{8}{\mathrm{cm}}^{\ensuremath{-}3}$ was obtained. A 10-mW violet external-cavity LD was used for the one-dimensional slowing of an effusive Yb atomic beam without a Zeeman slower resulting in a 35-fold increase in the number of trapped atoms. The overall characteristics of our compact violet MOT, e.g., the loss time of 1 s, the loading time of 400 ms, and the cloud temperature of 0.7 mK, are comparable to those in previously reported violet Yb MOTs, yet with a greatly reduced cost and complexity of the experiment.