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By the method of metal-organic chemical vapor deposition we have epitaxially grown effective samples of InAs/p-GaSb/n-GaSb/n-GaAs/InxGa1−xAs/Ge/Si(113) photovoltaic cells and investigated their photoelectric properties. The suitability of application of quality heterojunction diode structures in termophotovoltaic cells is experimentally proved.

An extremely broad emission spectrum is obtained for semiconductor optical amplifiers with multiple quantum wells fabricated on the substrate. The spectral width is nearly 400 nm (1200–1600 nm), which covers the entire usable bandwidth of an optical fiber. Broadband characteristics allow observing three novel effects: (i) the bi-directional guided effect of lasing mode in a bent waveguide of semiconductor optical amplifiers, (ii) the optical switching effect in one semiconductor optical amplifier for optical communication band, and (iii) the effect of separate confinement heterostructure layer thickness.

A non-conventional method of obtaining few-layer graphene (FLG) is suggested, which comprises repeatedly rubbing bulk graphite against semiconducting and insulating substrates. The obtained graphene/graphite structures consisting of rubbed-off layers behave like a semiconducting material with through-thickness anisotropy of carrier mobility reaching to 3000 cm/V⋅sec at the surface. The structure surface demonstrates more ordered and oriented character containing FLG. The suggested method allows easily obtaining graphene with pencil directly on paper, as well as graphene-based electronic components and circuits on paper and other substrates, which could enable flexible and cheap electronics. The observed phenomenon is universal, does not depend on the substrate material and could find a widespread application. Keywords—graphene; graphite; pencil; drawing

Analytical expressions of temperature dependencies of magnitude–frequency and phase–frequency characteristics of a HTSC RLC parallel circuit are obtained, where the resistance and inductance are non-linearly depended on the optical signal modulated by the intensity. It is shown that the magnitude–frequency and phase–frequency characteristics of circuits can be controlled by choosing the parameters of the HTSC thin film and optical “pump”.

Optical and photoelectrical properties of surface states of CdTe and ZnO, as well as their interfaces with electrolyte and chemisorbed oxygen were investigated. For that reason photoluminescence (PL), reflectance, electroreflectance (ER) and photocurrent spectra of CdTe, CdTe-chemisorbed oxygen, CdTe- and ZnO-electrolyte interfaces depending on temperature, concentration of charge carriers, light polarization, chemisorption and value of surface potential (SP) were experimentally investigated. Quasi-two-dimensional surface excitons (quasi-2DSE) and size-quantized quasi-2DSE were observed. A model of size-quantized quasi-2DSE associated with two-dimensional surface subbands (2DSS) was suggested. The behaviour of such excitons and the parameters of quantum inverse layer were determined. The binding energy of quasi-2DSE was evaluated.

We investigated vapour phase epitaxy (VPE)-grown ZnO nano-wires (NWs) on a Si substrate by scanning electron microscopy (SEM). SEM investigations show that there are single NWs and ensembles of NWs, among which we found straight and bend, perfect and non-perfect NWs, as well as NWs with clean surfaces and surfaces with the dark spots and features. After focused ion beam (FIB) polishing we found that every NW has a clean homogeneous surface, which allow us to conclude that all those dark spots and surface features of the NWs really are just surface features. The FIB milling gives information of the deeper interior of the NWs.

For semiconductor optical amplifiers fabricated on the substrate with multiple quantum wells, a very broad emission spectrum is obtained. The spectral width is nearly 400 nm (1200-1600 nm). Broadband characteristics allow observing three novel phenomena: (i) bi-directional guided effect of lasing mode in a bending waveguide of semiconductor optical amplifier; (ii) an optical switching effect in one semiconductor optical amplifier for optical communication band; and (iii) the effect of separate confinement heterostructure layer thickness

Superluminescent diodes with broad emission bandwidth characteristics and the mechanism of carrier distribution in the active layer are explored. Using InP substrate with five 6 nm InGaAsP quantum wells and two 15 nm InGaAs quantum wells, we get a very broad emission spectrum. The spectral width is nearly 400 nm, almost covering the range from 1250 nm to 1650 nm.

We investigated vapour-phase-epitaxy grown ZnO NWs on a Si substrate by SEM. SEM investigations show that there are single NWs and ensembles of NWs, among which we found straight and bend, perfect (with regular facets and smooth surfaces) and non-perfect (with irregular facets, non smooth surfaces, variable widths, damaged and particle) NWs, as well as NWs with clean surfaces, and surfaces with dark spots and features. After FIB polishing, we found that every NW has a clean homogeneous surface, which allows us to conclude that all its dark spots and surface features are really just surface features. The FIB milling gives information regarding the deeper interior of the NWs, i.e. buried structures within them, and whether or not those structures are propagating within them. But also here we found that there are no buried structures inside the NWs and the dark spots and features are not propagating within them, which lead to the result that NWs are totally homogeneous. The hexagonal facets of the NWs were observed on SEM images, which emphasize their good crystalline quality. The sizes of NWs were determined: the length is about 2–24 μm, and the width and height are about 200–500 nm.