Interface states and the transport of two-dimensional interface excitons in AlGaAs/GaAs structures

Using an unique combination of time and spatially resolved all optical photoluminescence measurement techniques, we have studied the properties of intrinsic excitons localized in quantum interface potentials in symmetric GaAs/Al0.3Ga0.7As double heterostructures. We find the transport of these interface excitons to be extremely sensitive to the time-dependent, spatially varying conduction, and valence band potentials near the heterointerface. The observed dynamics have been modeled, relying heavily on our previous kinetic results, which proved conclusively that H-band emission in our samples arises from the radiative recombination of quasi-two-dimensional excitons localized at the heterointerfaces, and find a simple electrostatic model to be in excellent quantitative agreement with experiment.