Molecular beam epitaxy of type II InSb/InAs nanostructures with InSb sub-monolayers

Molecular beam epitaxial growth of InSb sub-monolayer insertions in an InAs matrix, exhibiting intense mid-IR photoluminescence (PL) up to room temperature, is reported. The InSb insertions are fabricated by an exposure of the InAs surface to an antimony Sb4 flux. The nominal thickness of the insertions grown at different temperatures (400-485 °C) changes in the 0.6-1 monolayer range, resulting in the emission wavelength variation from 3.9 to 4.3 μm at 300 K. An integral PL intensity drop from 80 to 300 K does not exceed 20 times. The laser emission at a wavelength of 3.08 μm (T=60K) with the threshold current density of 3-4 kA/cm2 under pulse injection pumping has been demonstrated in a hybrid p-AlGaAsSb/InAs/n-CdMgSe double heterostructure with the multiple type II InSb/InAs nanostructures in the active region.