"Technical Physics Letters"

Borgardt, N. I.;Prihodko, A. S.;Seibt, M.

doi: 10.1134/S106378501612004Xpmid: N/A

Abstract The atomic structure of carbon materials is studied using the example of pyrocarbon and boronrich pyrocarbon by means of the method of reconstruction of the wave function in transmission electron microscopy. It is shown that the digital processing of the phase distributions of these functions allows us to find the average distance between the basal planes. Using the method of molecular dynamics for the formation of the test structures and obtaining for them the calculated phase distributions, the effect of depletion of the basal planes of the carbon atoms on the interplanar distance in the pyrocarbon materials is quantified.

Volynets, N. I.;Bychenok, D. S.;Lyubimov, A. G.;Kuzhir, P. P.;Maksimenko, S. A.;Baturkin, S. A.;Klochkov, A. Ya.;Mastrucci, M.;Micciulla, F.;Bellucci, S.

doi: 10.1134/S1063785016120129pmid: N/A

Abstract Analysis of the electromagnetic properties of composite materials based on epoxy resin with the addition of 0.5 wt % graphene nanoplates in the frequency range of 26–37 GHz is performed. The influence of types of epoxy resin with different viscosities and the type of solvent used (ethanol, acetone) on the electromagnetic response in this frequency range are determined. It is established that the least viscous epoxy resin, Epikote 828, and solvent ethanol are most effective for creation of a shielding covering in the microwave range. Composite materials with optimal composition provide attenuation of the electromagnetic signal at a level at least 10 dB in power for a film thickness of 1.1 mm.

Benemanskaya, G. V.;Dementev, P. A.;Kukushkin, S. A.;Lapushkin, M. N.;Osipov, A. V.;Timoshnev, S. N.

doi: 10.1134/S1063785016120026pmid: N/A

Abstract Photoemission studies of the electronic structure of the vicinal SiC(100) 4° surface, which was grown using a new substrate atom substitution method, and the Cs/SiC(100) 4° interface have been performed for the first time. The modification of spectra of the valence band and C 1s and Si 2p core levels in the process of formation of the Cs/SiC(100) 4° interface was analyzed. The suppression of the surface SiC state with a binding energy of 2.8 eV and the formation of a cesium-induced state with a binding energy of 10.5 eV were observed. The modification of the complex component structure in the spectrum of C 1s core level has been detected and examined for the first time. It was found that Cs adsorption on the vicinal SiC(100) 4° surface results in intercalation of graphene islands on SiC(100) 4° with Cs atoms.

Presnyakov, M. Yu.;Sladkopevtsev, B. V.;Belonogov, E. K.

doi: 10.1134/S1063785016120099pmid: N/A

Abstract Cross sections obtained by the method of a focused ion beam and fractures of the PdCu/Al2O3 nanocomposite synthesized by magnetron sputtering (MS) of alloy-type target PdCu and condensation in vacuum on the surface of nanoporous Al2O3 produced by anodic oxidation of aluminum foil are investigated using the methods of high-resolution scanning electron microscopy implemented on the basis of a Helios 600i setup (FEI, United States). Regularities of the formation of the structure and morphology of crystallites of vacuum condensate of Pd–Cu solid solution with a thickness of 0.1–4 μm on a surface with open porosity are disclosed. Approaches to the formation of the gradient structures near a free surface are discussed, and the conditions of the initiation of MS mechanisms of the formation of discrete, porous, and anisotropic condensates are found. Approaches to nonselective filling of nanopores in a dielectric by metal clusters and forming of the gradient structure of the nanocomposite PdCu/Al2O3 are carried out.

Davydov, S. Yu.;Lebedev, A. A.;Lebedev, S. P.;Sitnikova, A. A.;Sorokin, L. M.

doi: 10.1134/S1063785016120051pmid: N/A

Abstract The transition region of a 3C-SiC/4H-SiC heterostructure constituted by layers of the 3C and 4H polytypes has been studied. A previously proposed spinodal decomposition model was used to estimate the thickness ratio of 4H and 3C layers in comparison with the image furnished by transmission electron microscopy.

Kaveev, A. K.;Bursian, V. E.;Gastev, S. V.;Krichevtsov, B. B.;Suturin, S. M.;Volkov, M. P.;Sokolov, N. S.

doi: 10.1134/S1063785016120075pmid: N/A

Abstract Laser molecular-beam epitaxy has been employed to obtain layers of yttrium-iron garnet (YIG) Y3Fe5O12 on gallium nitride substrates. It was found that there exists a polycrystalline YIG phase without admixtures of other structural phases. A magnetic anisotropy of films of the “easy-magnetic plane” type was found. The gyromagnetic ratio and the demagnetizing field 4πM S were calculated.

Dudelev, V. V.;Zazulin, S. V.;Kolykhalova, E. D.;Losev, S. N.;Deryagin, A. G.;Kuchinskii, V. I.;Efanov, M. V.;Sokolovskii, G. S.

doi: 10.1134/S1063785016120191pmid: N/A

Abstract Fiber-coupled semiconductor lasers have been studied when pumped by high-power short electrical pulses of 5 ns width and leading front duration below 1 ns. In this pumping regime, it is possible to ensure significant sharpening of output pulses, the duration of which decreases below 80 ps for a single-mode laser and below 120 ps for a broad aperture multimode laser at an output peak optical power as high as 1.5 and 27 W, respectively.

Sorokin, S. V.;Sedova, I. V.;Gronin, S. V.;Belyaev, K. G.;Rakhlin, M. V.;Toropov, A. A.;Mukhin, I. S.;Ivanov, S. V.

doi: 10.1134/S1063785016120221pmid: N/A

Abstract We report on the molecular beam epitaxy (MBE) of heterostructures with CdTe/ZnTe quantum dots (QDs) with relatively low surface density, which could be used as single-photon emitters. The QDs were formed on the surface of a 3.1- to 4.5-monolayer-thick two-dimensional strained CdTe layer by depositing amorphous Te layer and its fast thermal desorption. Subsequent thermal annealing of the surface with QDs in the absence of external Te flux led to strong broadening and short-wavelength shift of the QD photoluminescence (PL) peak. Measurement of the micro-PL spectra of individual CdTe/ZnTe quantum dots in fabricated mesastructures with a diameter of 200—1000 nm allowed estimation of the QD surface density as ~1010 cm–2.

Tukachinsky, A. S.;Askinazi, L. G.;Balachenkov, I. M.;Belokurov, A. A.;Gin, D. B.;Zhubr, N. A.;Kornev, V. A.;Lebedev, S. V.;Khil’kevich, E. M.;Chugunov, I. N.;Shevelev, A. E.

doi: 10.1134/S1063785016120233pmid: