Recently we managed to prepare a three-component degenerate Fermi gas of 6Li with 50000 atoms in each state at a temperature of 215 nK, which corresponds to T/TF=0.37.
We studied the collisional stability of the gas in the magnetic field range from 0 to 750 G and found a broad and pronounced loss feature at 130 G. At approximately 580 G the sample remains quite stable, with 1/e lifetimes exceeding 30 s.
For a more quantitative analysis we deduced the three-body loss coefficient K3 from lifetime measurements.
The new results are available at arXiv:0806.0587.
We have reached condensation of 80000 6Li2 molecules in a dipole trap using an all-optical approach.
After being precooled in our magneto-optical trap (MOT) the 6Li atoms are transferred into the optical dipole trap, for which we use a 200 W fibre laser. The trap is established by two focussed beams with a waist of 50 µm crossing under an angle of about 7°.
Picture: Bimodal (condensate and thermal cloud) distributions at different stages of evaporation with final laser power between 120 - 61 mW. Before taking the image (after a time of flight of 10ms) the laser power is adiabatically ramped back to 120mW for all images.
the second diploma thesis (from Thomas Lompe) with the title:
"An apparatus for the production of molecular Bose-Einstein condensates"
was just finished. And is now available online:
The first diploma thesis with the title
"The setup of a Magneto Optical Trap for the preparation of a mesoscopic degenerate Fermi gas"
is now online.
a further step towards a molecular BEC could be reached: The Magneto Optical Trap (MOT)