We propose a cooling mechanism for ultracold fermionic atom ensembles, which capitalizes on the energy dependence of inelastic collisions near a Feshbach resonance. We first discuss a single magnetic resonance and find that the final temperature and cooling rate is limited by the resonance width. A concrete example for a $p$-wave resonance of ${}^{40}\text{K}$ is given. We then improve upon this setup by using both a sharp optical or radio-frequency-induced resonance and a broad magnetic resonance and show that one can improve upon temperatures reached with current technologies.

• Received 14 March 2009

DOI:https://doi.org/10.1103/PhysRevA.80.030702