Annealing effect on the shape of CdTe/ZnTe quantum wells

We report on the effect of thermal annealing on thin (001) CdTe/ZnTe single quantum wells. We found that the interdiffusion strongly modifies the optical spectra: (i) besides the expected blue shift, a strong reduction of the linewidth is observed in a first stage of annealing; we attribute this effect to a complete elimination of the larger islands present at the interface, (ii) in a second stage, ‘‘usual’’ interdiffusion occurs, with a slow rate in agreement with the diffusion coefficient extrapolated from reported self-diffusion data at higher temperatures.