Excitons and Band Splitting Produced by Uniaxial Stress in CdTe

A single exciton peak may be seen in the reflection spectrum of CdTe, a semiconductor with the cubic zinc‐blende structure. Some properties of this exciton and of the associated fluorescent phenomena are described. Under uniaxial compressive stress, the single exciton peak splits into two peaks corresponding to the splitting of the $\mathrm{J=}\frac{3}{2}$ valence band. The movement of the peaks as a function of stress has been determined for four directions of stress in the (110) plane. Within experimental error, the splittings are identical for a given stress applied in any direction. Thus, although the material is elastically anisotropic, the splitting may be described by one rather than two deformation potentials. These conclusions are consistent with the polarization properties of the exciton transitions. The polarization properties also show that under compressive stress the M_J=±½ band moves ``up'' and the $M_J\mathrm{=\pm }\frac{3}{2}$ band moves ``down.''