Carrier dynamics in site-controlled InGaAsN:H/GaAs quantum disks

Abstract

Hydrogenation of InGaAsN can be employed to fabricate site-controlled quantum structures with bandgap energies at the low-loss telecommunication window. In this work, laser pulse energy- and temperature-dependent photoluminescence and time-resolved photoluminescence optical spectroscopy techniques are applied to ensembles of 600 nm diameter and 9 nm thick InGaAsN:H quantum disks. From the data, carrier dynamics are investigated and physical parameters related to recombination processes are derived. Hydrogen passivation resulted in shallow tail states that are demonstrated to engage actively in the carrier dynamics. Physical trends typical of dilute nitride structures were also discerned through localization behavior in the conduction band minimum. Investigation of recombination dynamics provides deep understanding of inherent physical phenomena and will contribute to shorter feedback loops in enhancing the growth of InGaAsN:H nanostructures.