Résumé
Optical path modulation-an interference-based photoreflectance method-is used to study the influence of magnetic properties on the band structure of Cd1-xMnxTe. The results obtained due to the extreme sensitivity of this interferometric method indicate a renormalization of the effective mass under the influence of magnetic fluctuations, not observed so far. Time-dependent measurements supply additional arguments for the thermomagnetic character of the modulation and allow one to study magnetic relaxation phenomena. [S0163-1829(98)01012-1].