Correlation between the structure and luminescence of InAs submonolayer stacked nanostructures

The correlation between the structure, measured by atomic force microscopy (AFM), and luminescence, measured by photoluminescence (PL), of InAs submonolayer stacked (SMLS) nanostructures near the 2D to 3D transition is investigated. Topographic measurements using AFM reveal a significant change in the structure of uncapped InAs SMLS samples occurs under certain conditions. This structural change is attributed to the transition from 2D to 3D growth. Optical measurements by PL of corresponding capped SMLS samples showed a significant change in the luminescence properties, in the form of significant redshift and linewidth broadening, also occurs at the same conditions where the structural change occurred. Therefore, the data in the present work establishes a strong correlation between the structural and luminescence properties of InAs SMLS nanostructures. Furthermore, the results demonstrate that two forms of InAs SMLS, stacked 2D islands and 3D structures, possess distinct properties in terms of both structure and luminescence.