ABSTRACT
PACS numbers 78.60.Fi, 73.20.Dx, 78.65.Fa. Abstract Arsenic rich InAs/InAs1-xSbx strained layer superlattices (SLS's) grown on GaAs substrates by Molecular Beam Epitaxy (MBE) are studied for their potential application as infrared emitters. The long wavelength emission (4-11μm) is highly sensitive to superlattice design parameters and is accounted for by a large type II band offset, greater than in previously studied antimony rich InSb/InAs1-xSbx SLS's. High internal PL efficiencies (>10%) and intense luminescence emission were observed at these long wavelengths despite large dislocation densities. Initial unoptimised InAs/InAs1-xSbx SLS LED's gave ≈ 200nW of emission at 300K, with an internal quantum efficiency >0.05% in the 4.2μm CO2 absorption band. LED's with similar efficiencies are demonstrated at wavelengths extending out to 10μm, the longest yet reported for a 300K device.
