Neutral and charged multi-exciton complexes in single InAs quantum dots grown on InP(001)
Résumé
Lowdensity InAs/InP(001) quantum dots, formed by the ripening of self-organized quantum sticks, are subjected to optical spectroscopy by photoluminescence and micro-photoluminescence. The presence of neutral multi-exciton states in single quantum dots is observed up to the 4X state. The large energy spacing between the s- and p-shells (90 meV) reveals the strong spatial confinement of carriers in such InAs/InP quantum dots. Micro-photoluminescence studies show that some dots are charged which allows us to measure the exchange energies in the InAs/InP quantum dots.