We’ve finished installing a new (blue-detuned) laser beam to allow us to “stir” the molecular BEC in the ring, and otherwise perturb the system in a controllable way.

The DMD we’ve been using to create patterned optical potentials can certainly do more than just a simple ring. We’ve just had a first successful attempt at loading ultracold lithium atoms into multi-site ring traps. We probably shouldn’t call them lattices yet since the lattice spacing is still a couple of microns and we don’t expect there to be much tunneling of atoms between the potential wells. Once we have the beam projection system fully optimized and get the lattice spacing down closer to 1 micron, we’ll see about conducting the first experiments with ultracold atoms in ring lattices.

Today we created a ring shaped fermionic quantum gas for the first time.

After some tuning up, we’ll begin studies of persistent flow in fermionic superfluids.

With the “Feshbach” magnetic coils now working, we can control the interactions between lithium atoms when they are trapped in the glass “science” cell, and we have observed evaporative cooling of atoms in that trap. The density and temperature already look favorable enough to add in the beam that will shape the ultracold Fermi gas into a ring shape. One big step closer to our experimental goals.

For over a year now we (mostly Dan) have been designing, constructing, and testing a matched pair of objectives for projecting dipole trapping beams and imaging the atoms in the glass cell part of the vacuum chamber.  The cell windows have a nanopatterned anti-reflection coating that we really want to keep clean, so today the team donned bunny suits to reduce dust during the brief time during the installation that the cell windows won’t be fully covered/enclosed. Assuming we get as close to the 1.5 micron resolution limit as we did during bench testing, we’ll be in great shape for upcoming experiments.