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Structure formation during solidification of a Pd–Ni–Cu–P melt is studied. It is demonstrated that changes in the heat transfer conditions lead to a nonlinear change in the characteristics of the structure. The article presents the regimes of cooling the samples and the results of their structure and composition studies. It is found that a decrease in the cooling rate of the alloy leads to an increase in the size, proportion and composition of nanoinclusions in an amorphous matrix. X-ray diffraction method, electron probe microanalysis, transmission microscopy and scanning calorimetry are used for samples characterization. This article is part of the theme issue ‘Transport phenomena in complex systems (part 2)’.

In the study of materials on electron probe devices in the field of action of the electron beam, a contaminating hydrocarbon film is formed, which affects the experimental results. In this paper, we have studied the influence of a contamination film on carbon-film-coated dielectrics on the intensity of cathodoluminescence and characteristic X-ray lines. The absorption coefficient of the contamination film in the visible and UV ranges has been determined. Filming mechanisms at different parameters of the electron beam have been discussed.

Spectra of Eu3+ in various dielectric matrices (Gd2O3:Eu3+, Y2O3:Eu3+, Eu2O3, and mSiO2/Gd2O3:Eu3+ mesoporous particles) are studied by local cathodoluminescence. The results allowed identification of the local environment of Er3+ ions in amorphous samples and detection of the monoclinic Eu2O3 phase impurity in samples with yttrium oxide. The cathodoluminescence spectra of chemically pure Y2O3, Eu2O3, and Gd2O3 are recorded. Conclusions about the structural features of the materials are made and confirmed by other methods (XRD and EPMA).

We report on suppression of the Stark effect in (1.5-2)-monolayer(ML)-thick (GaN/AlN)100 multiple quantum well (MQW) structures grown on AlN/c-Al2O3 templates by plasma-assisted molecular beam epitaxy. Different stress relaxation mechanisms are revealed in these structures by using a multi-beam optical stress sensor in comparison with the 5ML-MQW structure. The former (with well thicknesses ⩽2MLs) demonstrate the nearly stress-free growth, whereas the latter structure with thicker wells exhibits the slow stress evolution from the high initial compressive stress to the nearly relaxed state with zero stress. Moreover, the former structures demonstrate a bright room-temperature cathodoluminescence (CL) with the single peak at the shortest wavelength 240 nm (1.5ML-QWs), while the latter shows much weaker multi-peak CL spectra in the spectral range of 270-360 nm.