Determination of Exciton Zeeman Splittings in Cd$\text{}_{1-x}$Mn$\text{}_{x}$Te from Faraday Rotation Measurements

Reflectivity and Faraday rotation measurements were carried out on Cd$\text{}_{1-x}$Mn$\text{}_{x}$Te bulk crystals in the complete zinc-blende range of composition 0 < x ≤ 0.71. From a comparison of the results of these two experiments for samples with x ≤ 0.3, we demonstrate that the Faraday angle Θ, measured in limited spectral range, is proportional to the energy splitting of exciton states ΔE, measured at the same temperature (2 K) and magnetic field B (up to 5 T). The determined proportionality constant was used to calculate ΔE values also for x > 0.3. This allowed us to find an empirical description of ΔE values for the whole range of compositions as a function of B and x.