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Abstract: We report the method of the epitaxial growth of the core–shell ZnTe/ZnMgTe nanowires. The morphology and the crystal structure of several samples grown in different processes have been studied by scanning electron microscopy, high resolution transmission electron microscopy and X-ray diffraction methods. It was shown that the ZnMgTe shell growth was clearly epitaxial with a good crystal quality. The average lattice spacing of the ZnTe cores and ZnMgTe shells have been calculated and Mg content in the shells has been estimated. It was documented that growing the shell lattice mismatched to the core induces the strain in the core. The model of the strain creation mechanism has been proposed. The presence of a shell with a larger energy gap than that of the core results in a strong emission in the spectral region near the band edge. [Copyright &y& Elsevier]

Abstract: The results of structural and magnetic characterization of GaMnSb layers grown on GaSb(001) and GaAs(111) substrates are presented. The presence of hexagonal, highly oriented MnSb inclusions embedded in GaSb matrix has been demonstrated. The lattice parameters of these inclusions were the same as those for bulk MnSb for the layers grown on GaSb(100) substrate while for the layers grown on GaAs(111) the MnSb inclusions were strained. The influence of a presence of MnSb clusters on the lattice parameter of GaSb matrix has been demonstrated. It was confirmed that in all cases the MnSb clusters exhibit a ferromagnetic behavior at room temperature. [Copyright &y& Elsevier]

Abstract: Implantation creates an opportunity for creation of ferromagnetic MnSb inclusions, which may be of interest for application in spintronics. Three sets of Mn-ion implanted (001) and (111) GaSb crystals prepared at different implantation and annealing conditions were investigated by X-ray diffraction methods applying both the standard laboratory source and synchrotron radiation. Polycrystalline phase of GaSb, formed as a result of GaSb matrix damage, was detected for all samples. For the same samples Sb and MnO2 inclusions were also observed. The phase composition of the samples is found to depend mainly on the energy and dose of Mn ions during the implantation process. For the lowest Mn dose, the layered structure was found. The strain caused by implanted buried layer depends on substrate temperature during implantation; an increased implantation temperature leads to strain relaxation. [Copyright &y& Elsevier]

High-Tc YBa2Cu3O7−x c-axis oriented thin films deposited by laser ablation were irradiated in-situ at their growth temperature by ultraviolet excimer-laser pulses with a fluence of up to 105 mJ/cm2. The resulting microstructure changes were investigated using X-ray diffraction and optical microscopy. Although the irradiation procedure leads to much smoother film surfaces, it also introduces a remarkable misorientation of YBaCuO grains creating a polycrystalline layer close to the top surface. [Copyright &y& Elsevier]

Abstract: This paper reports on the results of detailed X-ray diffraction studies of ZnTe and ZnMgTe nanowires grown by molecular beam epitaxy. As the aim of proper interpretation of the X-ray measurements of samples consisting of large number of nanowires we defined a virtual unit cell as an averaged one from all really existing cells in the large number of nanowires. The studies revealed that average structure of nanowires is characterized by a minor rhombohedral distortion. The occurrence of this distortion is attributed to the specific defect structure in the majority of nanowires. [Copyright &y& Elsevier]

Abstract: Advanced electronic devices based on III-N semiconductors, particularly these operated at the high power and high frequency or corrosive atmosphere, need elaboration of new technology for contacts metallization which are thermally and chemically stable. Performed studies aimed at the development of materials for applications in the improved metallization. Due to the unique combination of the metallic electro-thermal conductivity and ceramic resistance to oxidation and thermal stability, the MAX phases were chosen as the materials potentially applicable to this task. Particular interest lies in the MAX phases based on the Ti, Si and C or N atoms, especially on the Ti3SiC2 phase. The paper focuses on a comprehensive characterization of films grown by means of high-temperature magnetron Ti, Si and C co-sputtering. The complementary characterization by X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) is presented. XRD studies pointed out the presence of several phases in the investigated samples, therefore XAS as an atomic sensitive probe was applied to examine the average atomic order around Ti atoms as a function of the technological parameters and to point towards proper procedures to achieve the appropriate stoichiometry around Ti atoms and finally the Ti3SiC2 phase. [Copyright &y& Elsevier]

Abstract: The magnetic properties of a Cd1−x Mn x GeAs2: MnAs hybrid micro-composite have the signature of ferromagnetic order at room temperature. Magnetotransport reveals the presence of a large linear positive magnetoresistance, with maximum values of about 550% ( T) for . This is interpreted in terms of an effective medium approximation with the value and the shape of the magnetoresistance depending on the structural and electronic properties of the semiconductor rather than on its magnetic properties. The absence of an anomalous Hall effect leads to the conclusion that ferromagnetic ordering is not the only factor necessary for the occurrence of asymmetric scattering in granular ferromagnetic materials. [Copyright &y& Elsevier]

Abstract: The crystalline structure and surface morphology of Dy x O y dielectric films grown on Si substrates were studied by grazing incidence diffraction and absorption with use of synchrotron radiation and by atomic force microscopy. The crystalline structure and the roughness of Dy x O y films were found to be strongly dependent on the deposition rate. The dielectric-silicon interface depends on the type of gas used in the annealing process. Moreover, results from the near edge X-ray absorption studies, have revealed that none of the examined films has a stoichiometry close to the Dy2O3. The level of stoichiometry is determined by the technological conditions. Nevertheless, MOS structures with Dy x O y films (EOT∼23Å) have shown a rather good Dy x O y -Si interface properties, which can be further improve by thermal annealing, and introducing of several additives, therefore Dy x O y films can be considered as suitable candidates for gate dielectric in MOS devices. [Copyright &y& Elsevier]

High-pressure diffraction experiments for wurtzite-type zinc magnesium selenide were performed using a large-anvil X-ray diffraction press, MAX80, and synchrotron radiation. The pressure dependence of unit-cell parameters was determined for Zn0.53Mg0.47Se for pressures ranging up to 5.17 GPa. The value of bulk modulus and its pressure derivative were calculated from the pressure–volume dependence by fitting the Birch–Murnaghan equation of state (EOS). They are compared with reported data for ZnSe, MgSe and some related solid solutions. Photoluminescence (PL) data for Zn0.38Mg0.62Se were collected using a diamond-anvil cell at a lower pressure. These data show an evolution of the main deep-levels emission band: a narrowing of the spectrum, an increase of luminescence intensity and a blue shift. [Copyright &y& Elsevier]

Minimising the pressure gradients in large-anvil pressure cells is one of conditions for getting the high-quality results in investigations of structural and physical properties of the solid state. Pressure or temperature distributions in such devices are usually studied by scanning the sample with finely collimated X-ray beam. The previously reported pressure and temperature distributions in diamond anvil cells as well as temperature distributions in large-anvil cells, exhibit a strong dependence on materials of the sample environment and on the construction of sample assembly (data for pressure distribution in large-anvil cells were not available in literature). Present experiments were performed in energy-dispersive mode at MAX80 X-ray diffraction press installed at F2.1 beamline (Hasylab). The pressure distribution along the z-axis of a cylindrical NaCl sample mounted within a graphite heater embedded in a boron-epoxy cube was derived from the energetical positions of the 002 reflection along the sample scanned with white collimated X-ray beam. The pressure is found to be constant along the z-axis. [Copyright &y& Elsevier]

[Display omitted] • Quasi-ternary ZnO/MgO alloys are grown by MBE as an alternative to random alloys. • The highest mean Mg concentration is reaching 72%. • Critical thickness of Mg layers for retaining wurtzite crystallinity is established. • HAADF images confirmed thicknesses of ZnO and MgO layers assessed with two approaches of simulation of XRD diffractograms. • Biaxial strains at interfaces are partly responsible for creation of ZnMgO region, which influences WZ structure retainment. The analysis of heteroepitaxially grown ZnO/MgO superlattices on a -oriented ZnO substrates was described. The influence of unalike natural crystalline structures of ZnO and MgO on the interface's abruptness and retaining wurtzite crystallinity was studied. Wurtzite structure was found to be retained in the MgO thin barriers up to 1.5 nm, but creation of nonuniform biaxial strains and some interdiffusion of Mg from barriers to ZnO QW's seemed to be inevitable. The complex strain/composition heterogeneities can be explained by the difference of vapor pressure between Mg (p = 1.93 Pa) and Zn (p = 0.22 Pa) elements at growth temperatures and high mobility of Mg atoms, which are gladly incorporated into ZnO matrix. As a result, a subtle three monolayers in size ZnMgO film was created at the interfaces, which was partly responsible for retaining the wurtzite structure of coherently grown MgO layers. [ABSTRACT FROM AUTHOR]