Réalisation d'une mer de Fermi dipolaire d'atomes de chrome

Il s'agit de la première réalisation mondiale d'un gaz dégénéré dipolaire avec l'isotope fermionique du chrome.International audienceWe 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