Laser Trap Produces Degenerate Fermi Gas

Although Bose-Einstein condensates have not exactly become commonplace, intensive research over the last decade has greatly expanded scientists' understanding of this state of matter. Now researchers at Duke University in Durham, N.C., have used laser trapping to generate the fermionic counterpart of the Bose-Einstein condensate, a degenerate Fermi gas. The work promises to enable the construction of cold gas analogs of high-temperature superconductors.

Previously, teams had employed evaporative cooling in magnetic traps to create degenerate Fermi gases. The Duke researchers, in contrast, constructed a trap with a single focused beam from a stable 140-W CO₂ laser. Their two-component mixture of approximately 10⁵ atoms of ⁶Li was cooled to less than 4 µK in the trap.

They reported the work in the March 25 issue of Physical Review Letters.