Exciton reflection spectra of Fe-doped CdTe single crystals

The reflection spectra of CdTe crystals doped with Fe atoms are measured in the exciton region. The dependences are obtained of the exciton line position, and its halfwidth and intensity on impurity concentration. The position of the exciton line shifts linearly to shorter wavelengths with increasing impurity concentration. At 4.2 °K with increasing impurity concentration broadening and decrease in intensity of the line is found. At 77 °K the exciton line halfwidth shows no dependence on the doping level. For concentrations between 2 and 4 × 1019 cm−3 exciton „flash up”︁ is observed (exciton line narrowing in the spectrum), which is explained by the effect of an internal effective magnetic field due to exchange interaction between the impurity ions. [Russian Text Ignored.]