We report on molecular beam epitaxial growth of InSb submonolayer insertions in an InAs matrix, exhibiting intense mid-IR photoluminescence (PL) up to room temperature (RT). The InSb insertions are fabricated by an exposure of InAs surface to an antimony Sb4 flux. The nominal thickness of insertions grown at different temperatures (TS=400–485°C) ranges from 0.6 to 1.4 monolayer, as estimated from x-ray diffraction measurements of InSb∕InAs multiple submonolayer structures. This gives rise to the variation of the emission wavelength within the 3.9–4.3 μm range at RT. An integral PL intensity drop from 77 K to RT does not exceed 20 times.

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.

Modified TGS single crystals have been grown by doping with Cobalt (II) Phosphate in ferroelectric phase. The effects of different amounts of doping entities on the growth habit and P‐E hysteresis loop have been investigated. The experimental results show that while the spontaneous polarization Ps measured on variously doped crystals remains virtually unchanged, the coercive field values differ in dependence on the growth conditions and grown pyramidal features. The highest values of the coercive field Ec have been found to fall in the interval 800‐900 V/cm.

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The formation of organogels and microemulsions of lecithin in the presence of a biocompatible cosurfactant, oleic acid, was studied. Low content of oleic acid ([oleic acid]/[lecithin] < 0.1) in the lecithin–oleic acid–dodecane–water system leads to an expansion of the region of existence and to a decrease in the viscosity of lecithin organogels. At high contents of oleic acid ([oleic acid]/[lecithin] > 0.6), low‐viscosity microemulsion exists in the system. Phosphatidylethanolamine, lysophosphatidylcholine, and other phospholipids that are present as impurities in the commercial samples of soybean lecithin can act as cosurfactants. For the first time, the formation of lecithin organogels in the systems containing commercial samples of soybean lecithin with phosphatidylcholine concentrations of 69.3 wt% (Lipoid S75) and 52.9 wt% (Lipoid S45) and saturated aliphatic hydrocarbons is demonstrated. The gelation is observed at T =25 °C in octane, decane, dodecane, and hexadecane for Lipoid S75 and in dodecane and hexadecane for Lipoid S45. A decrease in the degree of purification of lecithin leads to an expansion of the regions of existence of the organogels and to a reduction of their viscosity.