Excitonic fine structure and binding energies of excitonic complexes in single InAs quantum dashes

摘要: The fundamental electronic and optical properties of elongated InAs nanostructures embedded in quaternary InGaAlAs barrier are investigated by means high-resolution spectroscopy many-body atomistic tight-binding theory. These wire-like shaped, self-assembled known as quantum dashes typically formed during the molecular beam epitaxial growth on InP substrates. In this paper, we study excitonic complexes confined emitting a broad spectral range from below 1.2 to 1.55 \ensuremath{\mu}m. We find peculiar trends for biexciton negative trion binding energies, with pronounced smaller size dashes. experimental findings then compared qualitatively explained theoretical analysis shows role correlation effects absolute values energies. Eventually, determine bright exciton fine structure splitting (FSS), where both experiment theory predict distribution varying 50 almost 180 \ensuremath{\mu}eV. identify several key factors determining FSS such nanostructures, including dash variation composition fluctuations.