Temperature-dependent photoluminescence from type-II InSb∕InAs quantum dots

We report on the photoluminescence (PL) studies of InSb-enriched quantum dots (QDs) which are grown by molecular beam epitaxy in an InAs matrix. InSb∕InAs heterostructures have a nominal thickness of InSb insertions in the range of 0.6–2 monolayers and exhibit bright PL up to room temperature in the mid-infrared spectral range. The PL temperature dependence gives evidence that each InSb insertion can be regarded as an ensemble of QDs subject to carrier transfer even at low temperatures. Both QD PL energy and line-shape variations with temperature can be described employing Fermi-Dirac carrier statistics.