Skip to Content

Fermi degenerate gas on a chip

Thywissen graph

On July 12, 2005, we observed a cloud of 40K atoms at 0.9TF. Analysis of data taken on August 4, 2005 revealed temperatures as low as 0.2TF, and an unambiguous signature of quantum degeneracy: non-Gaussian statistics in the time-of-flight distributions.

From the polylog fit of our lowest temperature data we find a temperature of 230nK, or about 0.2TF, where TF is 1.1µK, N is 6×104, and the oscillation frequencies in the trap are 2π×826Hz (radial) and 2π×49Hz (longitudinal).

To our knowledge, this is the first time this regime has been reached using an atom chip. The advantage of this approach is that evaporation can be quick (in our case, 6 seconds). A fast evaporation relaxes the vacuum quality constraint, allowing us to achieve Fermi degeneracy using a single MOT in a simple single-cell vacuum chamber.