InAsSb/InGaAs quantum nanostructures on InP (100) substrate: observation of 2.35 mum photoluminescence

A theoretical and experimental study of the electronic properties of InAsSb quantum dots (QDs) grown on InP substrate is presented. Unstrained bulk InAsSb presents a direct gap between 0.1 eV to 0.35 eV, suitable for mid infrared emitters (3-5 mum). However, strain and quantum confinement effects may limit the extension of the emission spectrum of these nanostructures towards longer wavelengths. Various combinations of barrier materials are considered in the simulations. First photoluminescence spectroscopy experiments on molecular beam epitaxy (MBE) grown samples show promising results. Triple stacks of InAs QDs embedded in a GaInAsP alloy lattice matched to InP and grown by the Stranski-Krastanov mode exhibit room temperature (RT) luminescence at about 2 mum. Emission wavelengths as long as 2.35 mum have been observed at RT in a InAsSb/InGaAs/InP structure. (