A chromium dipolar Fermi sea

We report on the production of a degenerate Fermi gas of 53Cr atoms, polarized in the stateF=9/2, mF = −9/2, by sympathetic cooling with bosonic S=3, mS = −3 52Cr atoms. We load inan optical dipole trap 30 000 53Cr atoms with one million 52Cr atoms. Despite this initial small numberof fermionic atoms, we reach a final temperature of T ≃ 0.6 × Tf (Fermi temperature), with upto thousand 53Cr atoms. This surprisingly efficient evaporation stems from an inter-isotope scatteringlength |aBF | = 85(±10) aB (Bohr radius) which is small enough to reduce evaporative losses of thefermionic isotope, but large enough to insure thermalization.