Transition behavior from coupled to uncoupled CdTe/ZnTe asymmetric double quantum wells

Photoluminescence (PL) measurements on CdTe/ZnTe double quantum wells grown by the simple method of double-well temperature-gradient vapor-transport deposition have been carried out to investigate the interband transitions in the double quantum wells. CdTe quantum wells were separated by a ZnTe potential-barrier width between 10 and 50 Å. The results for the PL data at 15 K demonstrated clearly that the transition behavior from coupled to uncoupled peaks depends on the ZnTe barrier thickness. Electronic subband energies and wave functions in the quantum wells were calculated by an envelope-function approximation taking into account the strain effects, and the transition values were in good qualitative agreement with those obtained from the experimental measurements.