Self-assembled InSb submonolayer quantum dots (QDs) in an InAs matrix have been grown by molecular beam epitaxy using ${\text{Sb}}_2$ and ${\text{As}}_2$ fluxes. The structures exhibit bright midinfrared photoluminescence up to room temperature. Intense room temperature electroluminescence with a peak at wavelength near $3.8\mu \text{m}$ was observed from $p\text{-}i\text{-}n$ light emitting diode structures containing ten InSb submonolayer QD sheets inserted within the InAs active region.

Room-temperature electroluminescence is reported from InAsSb multiple-quantum-well light-emitting diodes. The diodes exhibited emission in the mid-infrared peaking near 4μm. The spectral dependence on injection current at 4K was investigated and two transitions were identified, centered at 4.05 and 3.50μm, which are associated with the eigenstates of the confined holes inside the quantum well. The use of an Sb predeposition and As flux surface exposure during epitaxial growth was observed to have a major effect on the electroluminescence output.

The design, fabrication, and characterization of heterojunction photodiodes for room temperature operation in the mid-infrared (3–5μm) spectral range is described. Devices appropriate for carbon dioxide detection have been developed and studied. The authors report on the improvements obtained by increasing buffer layer thickness and also by using a blocking barrier to reduce leakage current.