In this thesis we measure and calculate the enhanced scattering rate for both cold thermal clouds and Bose-Einstein condensates. For Bose-Einstein condensates we find that the scattering rate is enhanced, due to the large densities and a temperature just below the critical temperature. The enhancement under typical experimental conditions with a Bose-Einstein condensate is up to a factor 3, while there is no enhancement for thermal clouds. The scattering rate influences both the number of particles and the average energy per particle. For both the energy and the number of particles a theoretical prediction is compared with an experimental result. For the number of particles in a cloud both with and without a Bose-Einstein condensate and the energy in a cloud without a Bose-Einstein condensate, we find that theory and experiment agree within their uncertainties. In the case of the energy per particle in a cloud with a Bose-Einstein condensate, we included a cooling effect for condensed atoms that become thermal, however our experimental results are not sufficient to confirm this theory.In this thesis we measure and calculate the enhanced scattering rate for both cold thermal clouds and Bose-Einstein condensates. For Bose-Einstein condensates we find that the scattering rate is enhanced, due to the large densities and a temperature just below the critical temperature. The enhancement under typical experimental conditions with a Bose-Einstein condensate is up to a factor 3, while there is no enhancement for thermal clouds. The scattering rate influences both the number of particles and the average energy per particle. For both the energy and the number of particles a theoretical prediction is compared with an experimental result. For the number of particles in a cloud both with and without a Bose-Einstein condensate and the energy in a cloud without a Bose-Einstein condensate, we find that theory and experiment agree within their uncertainties. In the case of the energy per particle in a cloud with a Bose-Einstein condensate, we included a cooling effect for condensed atoms that become thermal, however our experimental results are not sufficient to confirm this theory.

Feb 11, 20150 citations

EXPERIMENTAL ASPECTS OF BOSE-EINSTEIN CONDENSATION

A. C. Wilson, Callum R. McKenzie

Dec 1, 20000 citations

Experimental Study on Evaporative Cooling and Bose–Einstein Condensation of Sodium Atoms

Kou Matsui, Takahiko Shobu, Yasunori Tanami +3 more

We have developed an apparatus for creating Bose–Einstein condensates of sodium atoms. Radio-frequency-induced forced evaporative cooling was studied experimentally and optimized to stably create sodium condensates containing a large number of atoms. The transition temperature, the spatial distribution of the condensate, and the aspect ratio of the Bose–Einstein condensate were analyzed quantitatively and compared with theoretical predictions. Several methods of ramping down the rf for evaporative cooling were tested.We have developed an apparatus for creating Bose–Einstein condensates of sodium atoms. Radio-frequency-induced forced evaporative cooling was studied experimentally and optimized to stably create sodium condensates containing a large number of atoms. The transition temperature, the spatial distribution of the condensate, and the aspect ratio of the Bose–Einstein condensate were analyzed quantitatively and compared with theoretical predictions. Several methods of ramping down the rf for evaporative cooling were tested.

Journal of the Physical Society of JapanAug 10, 20092 citations

Studies of Bose-Einstein Condensates

Michael R. Andrews, Dallin Durfee, S. Inouye +3 more

Journal of Low Temperature PhysicsJan 1, 19986 citations

Efficient production of large K39 Bose-Einstein condensates

Robert L. D. Campbell, Robert P. Smith, Naaman Tammuz +3 more

We describe an experimental setup and the cooling procedure for producing $^{39}\mathrm{K}$ Bose-Einstein condensates of over $4\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms. Condensation is achieved via a combination of sympathetic cooling with $^{87}\mathrm{Rb}$ in a quadrupole-Ioffe-configuration (QUIC) magnetic trap and direct evaporation in a large-volume crossed optical dipole trap, where we exploit the broad Feshbach resonance at 402 G to tune the $^{39}\mathrm{K}$ interactions from weak and attractive to strong and repulsive. In the same apparatus we create quasipure $^{87}\mathrm{Rb}$ condensates of over $8\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms.We describe an experimental setup and the cooling procedure for producing $^{39}\mathrm{K}$ Bose-Einstein condensates of over $4\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms. Condensation is achieved via a combination of sympathetic cooling with $^{87}\mathrm{Rb}$ in a quadrupole-Ioffe-configuration (QUIC) magnetic trap and direct evaporation in a large-volume crossed optical dipole trap, where we exploit the broad Feshbach resonance at 402 G to tune the $^{39}\mathrm{K}$ interactions from weak and attractive to strong and repulsive. In the same apparatus we create quasipure $^{87}\mathrm{Rb}$ condensates of over $8\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms.

arXiv:1010.3739Physical Review ADec 8, 201045 citations

We describe an experimental setup and the cooling procedure for producing

^{39}\mathrm{K}

Bose-Einstein condensates of over $4\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms. Condensation is achieved via a combination of sympathetic cooling with

^{87}\mathrm{Rb}

in a quadrupole-Ioffe-configuration (QUIC) magnetic trap and direct evaporation in a large-volume crossed optical dipole trap, where we exploit the broad Feshbach resonance at 402 G to tune the

^{39}\mathrm{K}

interactions from weak and attractive to strong and repulsive. In the same apparatus we create quasipure

^{87}\mathrm{Rb}

condensates of over $8\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms.