Thermoreflectance spectra of CdCr2Se4 in the vicinity of the Curie temperature

Abstract Thermoreflectance studies have been done on undoped and about 1 per cent In doped single crystals of CdCr 2 Se 4 at the temperature above and below the Curie points. The red-shift of the dip in the low energy region of the spectra (∼1.3 eV) and the appearance of the dips at the higher energy regions of the spectra (∼1.95 and ∼2.6 eV) below the Curie temperature are attributed to the exchange interactions between the carrier spins and the spins of the magnetic atoms.