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 h ighest Cd concentration (x=0.43), the diffusion length increased with tempe rature up to 225 K and then dropped at higher temperatures. Diffusion lengt hs were 0.21 mu m at 8 K, 0.38 mu m at 225 K, and 0.24 mu m at room tempera ture. For the well with least Cd concentration (x=0.24), longer diffusion l engths were obtained. The nature of the diffusing carriers is also discusse d. (C) 1999 American Institute of Physics. [S0003-6951(99)03905-4].