Faraday rotation from Zn_1-xFe_xSe epilayers

We present Faraday rotation measurements on Zn1-xFe xSe films grown by molecular beam epitaxy. The samples exhibit giant Faraday rotation characteristic of diluted magnetic semiconductors. Measurements were carried out at T=4.2 K and in magnetic fields up to 8 T. The Faraday rotation angle shows a strong resonance for photon energies close to the band gap. The resonance curves were fitted by a simple dielectric model using the exciton oscillator strength as a fitting parameter.