From Phys. Rev. Lett. submission:

"Evaporative cooling was performed to cool fermionic ¹⁷³Yb atoms in a crossed optical dipole trap. The large elastic collision rate leads to efficient evaporation and we have successfully cooled the atoms to 0.37±0.06 of the Fermi temperature, that is to say, to a quantum degenerate regime. In this regime, a plunge of evaporation efficiency was observed as a result of Fermi degeneracy."

[Received 8 July 2006; published 17 January 2007]
Phys. Rev. Lett. 98, 030401 (2007)