Diffusion lengths of excited carriers in CdxZn1−xSe quantum wells

Diffusion lengths of excited carriers in a CdxZn1−xSe multiple quantum well structure were determined for temperatures between room temperature and 8 K from cathodoluminescence measurements. The diffusion length was found to depend upon temperature and Cd concentration of the quantum well. For the highest Cd concentration (x=0.43), the diffusion length increased with temperature up to 225 K and then dropped at higher temperatures. Diffusion lengths were 0.21 μm at 8 K, 0.38 μm at 225 K, and 0.24 μm at room temperature. For the well with least Cd concentration (x=0.24), longer diffusion lengths were obtained. The nature of the diffusing carriers is also discussed.