Tunneling dynamics in CdTe/(Cd,Zn)Te asymmetric double-quantum-well structures

Abstract

Carrier tunneling through (Cd,Zn)Te barriers of different thicknesses is investigated in CdTe/Cd,Zn)Te asymmetric double quantum wells by use of time-resolved photoluminescence and steady-state photoluminescence excitation experiments. The strong dependence of the observed tunneling times on the barrier thickness indicates a resonant tunneling behavior. The analysis of our results allows us to identify the importance of excitons rather than free-carrier states for the tunneling mechanism.