[en] In this work, we fabricated a flexible wide spectral range absorber using diamond-graphite mixture. Angular reflectivity, diffusional reflectivity and transmittance were investigated in the range 85-8000 cm^-1 (117-1. 25 µm). (authors)

[en] The ferromagnetic Fe-In_2O_3 nanocomposite thin film has been synthesized by the thermite Fe_2O_3 + In → Fe-In_2O_3 reaction. The transmittance (400 - 1100 nm) was measured at temperatures from 320 to 5 K. It was found that the transmittance increases when temperature decreases. For wavelength 600, 700, 800, 900 and 1000 nm maximum change of transmittance was ~ 3.2, 4.2, 4.8, 5.1 and 5.4 %, respectively. From transmittance spectra, spin glass-like behavior was observed near ~ 36 K and confirmed by magnetization measurements. The Verwey transition was identified at ~ 127 K by magnetization measurements. We have shown direct relationship between transmittance and magnetization of nanocomposite Fe - In_2O_3 thin film near ~ 36 K and give proposed possible mechanism this phenomena. (authors)

[en] In accordance with model calculations, one-dimensional photonic crystals (OPC) based on SiO₂/Si₃N₄ have been synthesized using plasma chemical vapor deposition. A good agreement has been obtained between the experimental and calculated data in terms of the optical properties of the OPC. Based on the synthesized OPCs, optical elements with a gold sublayer have been obtained for the experimental observation of the Tamm plasmon-polariton

[en] The thin-film solid-state reaction between elemental Ge and Mn across chemically inert Ag layers with thicknesses of (0, 0.3, 1 and 2.2 µm) in Ge/Ag/Mn trilayers was studied for the first time. The initial samples were annealed at temperatures between 50 and 500 °C at 50 °C intervals for 1 h. The initiation temperature of the reaction for Ge/Mn (without a Ag barrier layer) was ~ 120 °C and increased slightly up to ~ 250 °C when the Ag barrier layer thickness increased up to 2.2 µm. In spite of the Ag layer, only the ferromagnetic Mn₅Ge₃ compound and the Nowotny phase were observed in the initial stage of the reaction after annealing at 500 °C. The cross-sectional studies show that during Mn₅Ge₃ formation the Ge is the sole diffusing species. The magnetic and cross-sectional transmission electron microscopy (TEM) studies show an almost complete transfer of Ge atoms from the Ge film, via a 2.2 µm Ag barrier layer, into the Mn layer. We attribute the driving force of the long-range transfer to the long-range chemical interactions between reacting Mn and Ge atoms. - Graphical abstract: The direct visualization of the solid state reaction between Mn and Ge across a Ag buffer layer at 500 °C. - Highlights: • The migration of Ge, via an inert 2.2 µm Ag barrier, into a Mn layer. • The first Mn₅Ge₃ phase was observed in reactions with different Ag layers. • The Ge is the sole diffusing species during Mn₅Ge₃ formation • The long-range chemical interactions control the Ge atomic transfer.

[en] Highlights: • Ferromagnetic Fe–In_2O_3 nanocomposites were prepared by solid-state reactions. • The reaction starts above the initiation temperature T_i_n ∼ 180 °S. • The reaction products contain α-Fe nanocrystals enveloped by an In_2O_3 shell. • The formation mechanisms of the Fe–In_2O_3 core/shell-like structures were discussed. - Abstract: We have successfully synthesized ferromagnetic Fe–In_2O_3 nanocomposite thin films for the first time using the thermite reaction Fe_2O_3 + In = In_2O_3 + Fe. The initial In/Fe_2O_3 bilayers were obtained by the deposition of In layers on α-Fe_2O_3 films. The reaction occurs in a self-propagating mode in a homogeneous thermal film plane field at heating rates above 20 K/s and at temperatures above initiation temperature T_i_n ∼ 180 °S. At heating rates lower than 20 K/s the mixing of the In and Fe_2O_3 layers occurs across the whole In/Fe_2O_3 interface and the synthesis of the ferromagnetic α-Fe phase starts above the initiation temperature T_i_n = 180 °S. X-ray diffraction, X-ray photoelectron spectroscopy, Mossbauer spectroscopy, transmission electron microscopy and magnetic measurements were used for phase identification and microstructure observation of the synthesized Fe–In_2O_3 samples. The reaction products contain (1 1 0) textured α-Fe nanocrystals with a diameter around 100 nm and surrounded by an In_2O_3 matrix. These results enable new efficient low-temperature methods for synthesizing ferromagnetic nanocomposite films containing ferromagnetic nanoclusters embedded in transparent conducting oxides