Hot electron spectroscopy of the GaAs/AlAs/GaAs band structure

Hot electron spectroscopy was used to study transport through two GaAs/AlAs/GaAs heterostructures with undoped AlAs layers of 10 and 13 nm width. We observed transport through the individual bound states of the quantum well formed in the X-valley of the GaAs/AlAs/GaAs system. From the energetic positions of these bound states, we derived X-AlAs - Gamma(GaAs) = 136 meV for both samples and m* (X,AlAs) = (0.8 +/- 0.1)m(0) for the 10 nm sample and m*(X,AlAs) = (0.7 +/- 0.1)m(0) for the 13 nm sample.