Persistent photoconductivity and electron mobility in In$_{0.52}$Al$_{0.48}$As/In$_{0.53}$Ga$_{0.47}$As/In$_{0.52}$Al$_{0.48}$As/InP quantum-well structures
Abstract:
The influence of the width of the quantum well $L$ and doping on the band structure, scattering, and electron mobility in nanoheterostructures with an isomorphic In$_{0.52}$Al$_{0.48}$As/In$_{0.53}$Ga$_{0.47}$As/In$_{0.52}$Al$_{0.48}$As quantum well grown on an InP substrate are investigated. The quantum and transport mobilities of electrons in the dimensionally quantized subbands are determined using Shubnikov–de Haas effect measurements. These mobilities are also calculated for the case of ionized-impurity scattering taking into account intersub-band electron transitions. It is shown that ionized-impurity scattering is the dominant mechanism of electron scattering. At temperatures $T <$ 170 K, persistent photoconductivity is observed, which is explained by the spatial separation of photoexcited charge carriers.