Electron dynamics in InNxSb1–x

Electron transport properties in InNxSb1–x are investigated for a range of alloy compositions. The band structure of InNxSb1–x is modeled using a modified k·p Hamiltonian. This enables the semiconductor statistics for a given x value to be calculated from the dispersion relation of the E– subband. These calculations reveal that for alloy compositions in the range 0.001<=x<=0.02 there is only a small variation of the carrier concentration at a given plasma frequency. A similar trend is observed for the effective mass at the Fermi level. Measurements of the plasma frequency and plasmon lifetime for InNxSb1–x alloys enable the carrier concentration and the effective mass at the Fermi level to be determined and a lower limit for the electron mobility to be estimated

Preparation and characterization of Bi26–2xMn2xMo10O69-d and Bi26.4Mn0.6Mo10–2yMe2yO69-d(Me = V, Fe) solid solutions

Received: 06.06.2017; accepted: 23.06.2017; published: 14.07.2017.Single phase samples of bismuth molybdate, Bi26Mo10O69, doped with Mn on the bismuth sublattice and V, Fe on the molybdenum sublattice were found to crystallize in the triclinic Bi26Mo10O69 structure at low doping levels and in the monoclinic Bi26Mo10O69 structure - at higher dopant concentration. The assumption that all Mn ions have an oxidation state of +2 was confirmed by means of magnetic measurement results analysis using Curie-Weiss law. Conductivity was investigated using impedance spectroscopy. The conductivity of Bi26.4Mn0.6Mo9.6Fe0.4O69-d was 1.2*10-2 S*cm-1 at 973 K and 2.2*10-4 S*cm-1 at 623 K, and the conductivity of Bi26.4Mn0.6Mo9.2V0.8O69-d was 2.2*10-3 S*cm-1 at 973 K and 2.2*10-5 S*cm-1 at 623 K

Synthesis, Structure, and Investigation of Bismuth Niobate Doped by Alkaline-Earth Elements

Polycrystalline samples with general formula Bi3

Materials based on BIFEVOX and bismuth or iron simple oxides nanopowders

Received: 22.09.2017; accepted: 17.10.2017; published: 20.10.2017.Compositions of composite materials based on BIFEVOX and nanopowders of bismuth and iron oxides have been obtained. The absence of chemical interaction between the components has been proved, the total electrical conductivity of materials in the average temperature region has been determined. It has been shown that under the selected formation conditions, it has not yet been possible to achieve significant improvement of the functional characteristics of heterogeneous compositions in comparison with individual phases. However positive results on chemical and structural stability give way to further investigations.The work was partially supported by the Scholarship of the President (SP-3376.2016.1) and Russian Foundation for Basic Research (project No 17-53-04098)

Optical properties and energy band parameters of luminescent CaMoO 4 :Bi ceramics

We studied the role of intrinsic defects of matrix and Bi dopant in the formation of optical properties and energy structure of CaMoO 4 :Bi ceramic. Non-elementary luminescence was detected in a pure CaMoO 4 matrix due to radiative transitions in intrinsic vacancy-type defects, which are associated with non-stoichiometry in calcium. The experiment showed that Bi ions act as quenchers of luminescence. © Published under licence by IOP Publishing Ltd.The work has been funded by the Ministry of (Governmenttask№3.1485.2017/4.6)

Photoluminescence spectroscopy of bandgap reduction in dilute InNAs alloys

Photoluminescence (PL) has been observed from dilute InNxAs1–x epilayers grown by molecular-beam epitaxy. The PL spectra unambiguously show band gap reduction with increasing N content. The variation of the PL spectra with temperature is indicative of carrier detrapping from localized to extended states as the temperature is increased. The redshift of the free exciton PL peak with increasing N content and temperature is reproduced by the band anticrossing model, implemented via a (5×5) k·p Hamiltonian