Magnetization and exchange interactions in Zn1−xFexTe diluted magnetic semiconductors

Magnetization and magnetoreflectivity measurements have been performed in diluted Zn1−xFexTe compounds, at T=1.8 K. The magnetization of Fe2+ ions is quantitatively analyzed in the framework of the crystal field and spin–orbit coupling model and is in excellent agreement with the crystal field and spin–orbit coupling parameters we deduced from previous optical studies (Δ=−2693 cm−1 and λ=−102.2 cm−1). The six Zeeman-like components of the free exciton spectrum are observed, in Faraday or Voigt configuration. The comparison between the energy splittings and the magnetization data yields the values for the conduction and valence exchange parameters: N0α=0.29±0.09 eV and N0β=−1.50±0.17 eV.