Optical Properties of III–V Quantum Dots

摘要: Results on excitonic properties of few and many particles-complexes confined in self-organized In(Ga)As/GaAs InGaN/GaN quantum dots (QDs) are highlighted. The renormalization transition energies InGaAs QDs is found to be proportional the number excitons per dot wetting layer. Resonant Raman scattering such reveals localized TO- LO-like phonon modes being blue shifted with respect unstrained InAs bulk modes, a interface mode. largely independent structural within different samples. Embedding an well shifts QDs’ emission lower energies. reduction strain identified as main reason for this redshift. Binary InAs/GaAs ensembles show distinct formation subensembles due self-similar shapes height variations steps integral monolayers. A decreasing excited states QD size observed. Spectra individual reveal biexciton binding energy changing from antibinding decreases. trend explained by varying bound hole states. Furthermore, monotonous decrease exciton fine-structure splitting large values 0.5 meV small even negative found, highlighting effect piezoelectricity. For nitride structures clear proof quantum-dot nature provided resonantly time-resolved photoluminescence. Single InGaN emission-lines pronounced linear polarization, which attributed valence band structure wurtzite type nitrides.