Résumé
We have fabricated and characterized a n-doped InSb Faraday isolator in the mid-IR range (9.2 µm). A high isolation ratio of $\approx$30~dB with a transmission over 80\% (polarizer losses not included) is obtained at room temperature. Further possible improvements are discussed. A similar design can be used to cover a wide wavelength range (lambda ~ 7.5-30 µm).