Dynamical transport of photoexcited carriers between a narrow and a wide quantum well embedded in a GaAs/AlAs superlattice

The temperature dependence of the emission properties in a composite quantum well structure consisting of a wide and a narrow GaAs quantum well (QW) separated by and embedded in a GaAs/AlAs short-period superlattice (SPS) has been studied by steady-state and time-resolved photoluminescence (PL) measurements. At low temperatures View the MathML source, distinct PL peaks originating from the QWs and SPS are observed. When the temperature is increased to View the MathML source, the PL intensity of the wide QW with strongly confined states significantly increases, while the ones of the narrow QW and the SPS gradually decrease. Above View the MathML source, however, the PL intensity of the wide QW decreases and the others increase. The temperature dependence of the PL dynamics indicates that the PL properties of the composite QWs are connected to Bloch-type transport of photoexcited carriers in the SPS between the wide and narrow QW.