Luminescent properties of self-assembled Ge(Si)/SOI nanoislands embedded in twodimensional photonic crystal (PhC) slabs with and without L3 cavities were studied with PhC period a varied between 350 and 600 nm. For small periods (a£450 nm), the nanoisland luminescence, which spans over the wavelength range from 1.2 to 1.6 μm, overlaps with the PhC bandgap resulting in a coupling with the localized modes of an L3 cavity. It is shown that for larger periods (a>450 nm), nanoisland emission couples to the radiative modes above the bandgap located in the vicinity of the Г-point of the photonic crystal Brillouin zone and is characterized by the low group velocity. In this case, a significant (up to 35-fold) increase in the PL intensity was observed in a number of PhCs without a cavity. From a technological point of view, the latter result makes such types of photonic crystal structures particularly promising for the realization of Si-based light emitters operating in the telecommunication wavelength range because, firstly, their manufacture does not require a precise cavity formation and, secondly, they provide a much larger area for the radiating region, as compared with PhC cavities.

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The observation of a stimulated emission at interband transitions in monocrystalline n-InN layers under optical pumping is reported. The spectral position of the stimulated emission changes over a range of 1.64 to 1.9 μm with variations of free electron concentration in InN layers from 2·1019 cm−3 to 3·1017 cm−3. The main necessary conditions for achieving the stimulated emission from epitaxial InN layers are defined. In the best quality samples, a threshold excitation power density is obtained to be as low as 400 W/cm2 at T = 8 K and the stimulated emission is observed up to 215 K. In this way, the feasibility of InN-based lasers as well as the potentials of crystalline indium nitride as a promising photonic material are demonstrated.

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YBa2Cu3O (YBCO) films were fabricated by magnetron sputtering with modification of the substrate surface by preliminary topology masks. Formation features of Josephson junctions on bicrystal Zr1−xYxO2 (YSZ) substrates have been considered. The structural and electrical properties of such junctions were investigated. As a result, the presented technology allows us to fabricate YBCO structures on YSZ substrates with a buffer cerium dioxide (CeO2) layer where YBCO film sputtering is the final stage of structure formation. In particular, long Josephson junctions with good characteristics have been fabricated by this technology and measured, allowing us to achieve critical currents of 80 mA for 150 um junctions.