INFLUENCE OF THE BARRIER HEIGHTS ON VERTICAL TRANSPORT IN CDTE CDMNTESUPERLATTICES/

Vertical transport in CdTe/Cd1-xMnxTe superlattices has been studied b y an all-optical method. The diffusion lengths of carriers in 40/40 An gstrom and 50/50 Angstrom superlattices at 2 K are found to be 0.21 an d 0.11 mu m, respectively. At temperatures below 20 K, the transport o ccurs by the hopping of excitons between localized states. At higher t emperatures, the excitons are activated into extended states so that t he transport efficiency increases. In an external magnetic field the v ertical transport increases because of a reduction in the barrier heig ht of the heavy hole.