High-density, uniform InSb∕GaSb quantum dots emitting in the midinfrared region

Abstract

The authors have developed a multistep molecular-beam epitaxy growth technique which allows them to grow InSb quantum dots with high structural perfection and high density. This technique consists in the deposition at a very low temperature followed by a properly designed annealing step. Fully strained InSb∕GaSb quantum dots with a density exceeding 7×1010cm−2 and lateral sizes in the 20–30nm range have been obtained. Narrow photoluminescence emission is obtained around 3.5μm up to room temperature.

Binding energy of hydrogenic impurities in quantum dots under intense laser radiation

“…A good candidate is InSb/GaSb, for which a 2D ∼ 30 nm. QDs based on InSb/GaSb with lateral sizes in the range 20 − 30 nm [33] or even smaller, of the order of 10 nm [34], have been grown by molecular-beam epitaxy. As we pointed out before, the intensity values for which our approach is valid should be in the range 10 7 − 10 12 W/cm 2 for commonly used laser frequencies.…”

MBE growth and interface formation of compound semiconductor heterostructures for optoelectronics

“…No threading dislocations are observed in contrast to the previous results obtained for usual MBE growth conditions. By tilting the sample to get the interface inclined to the electron beam and to adjust g = 220 diffraction conditions we have demonstrated that the InSb QDs are perfectly coherent and are very uniform in size [34].…”

“…Such an element playing a role similar to a surfactant, it can be considered as a virtual-surfactant, or self-surfactant [28,29]. In such a situation however, the impact of a 2D growth can be either positive, as in the case of (Ga,In)(N,As)(Sb) QWs growth on GaAs [10,45,46], or negative as in the case of InSb QDs growth on GaSb [33,34]. The growth conditions must thus be precisely adjusted in accordance with the target.…”

Quantum dots and quantum dashes in the narrow-gap InSb/InAsSbP system

“…To penetrate in the long-wavelength region (l42 mm) it needs to produce quantum dots based on the narrow-gap semiconductors such as InSb and InAsSb solid solutions obtained in InAs or GaSb enriched matrix that are prospective for the fabrication of emitters and detectors, which can operate in mid-infrared spectral range 3-4 mm [7]. It would be paid an attention that the lattice mismatch between InSb and InAs binary compounds is 7% that is similar to the InAs/GaAs quantum dots system described elsewhere [8].…”