Step pseudomorphic asymmetric wells: an optical study in the framework of III - V strain-induced sub-two-dimensional quantum systems

Abstract

An optical study of the basic epitaxial structure for the fabrication of strain-induced sub-two-dimensional quantum systems was performed by comparing photoreflectance measurements with calculations of the energy positions and the relative intensities of the interband transitions originating in the different regions of the sample. It is shown that by taking advantage of the explicit calculation of the overlap integrals associated with the asymmetric well transitions, the complicated optical response of the whole heterostructure can easily be interpreted. This, in turn, enables the development of the optical investigation of the inner GaAs well (the active region of the device) by means of photoreflectance even at room temperature, as an alternative to the most commonly used low-temperature luminescence techniques.