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The influence of the level of modifier content on the behavior of the optical characteristics of thermally deposited films of arsenic triselenide chalcogenide glasses is investigated. A parallel shift of the absorption edge towards short wavelengths and a decrease in the slope of the exponential “tail” are observed. The increase in the slope of the Urbach energy dependence with an increasing modification level can be explained both by an increase in the concentration of metal-metal bonds, due to a deviation from stoichiometry, and by a transition through the value of the coordination number corresponding to the point of the topological phase transition. A simultaneous decrease in the band gap apparently indicates an increase in the defectiveness of the structure. In addition, it may indicate the presence of a higher concentration of trap states near the Fermi level, leading to a corresponding smearing in the “tails” of conductivity in chalcogenide glassy semiconductors (CGS).

В исследованных халькогенидных стеклообразных полупроводников (ХСП) обнаружен эффект влияния модификации на характер температурной зависимости электропроводности. Величина последней увеличивается с уменьшением ширины запрещенной зоны и, соответственно, с увеличением энергии активации. Указанная энергия коррелирует с изменением высоты потенциального барьера на контакте между металлом и халькогенидным стеклообразным полупроводником для различных составов материалов As2Se3 и As2S3. Отмечена существенная роль одиночной пары электронов, принадлежащей атомам модифицирующей примеси. Пара электронов отвечает за реализацию неупорядоченной и дефектной структуры, а также за формирование энергетической системы локальных состояний, оказывающих влияние на процесс переноса носителей заряда.

The paper reports the results of a comparative study of optical properties of thin films of arsenic chalcogenides of the As–S system taking into account the effect of their modification with molybdenum. An analysis of the experimental optical transmission spectra made it possible to calculate the dispersion curves of the refractive, absorption, and extinction coefficients of the medium, as well as the real and imaginary components of the complex permittivity. The revealed features of the behavior of the obtained spectral dependences are associated with the stereoeffect of a lone electron pair (LEP) in the structure of the arsenic compound under study.

The paper reports the results of a comparative study of optical properties of thin films of arsenic chalcogenides of the As–S system taking into account the effect of their modification with molybdenum. An analysis of the experimental optical transmission spectra made it possible to calculate the dispersion curves of the refractive, absorption, and extinction coefficients of the medium, as well as the real and imaginary components of the complex permittivity. The revealed features of the behavior of the obtained spectral dependences are associated with the stereoeffect of a lone electron pair (LEP) in the structure of the arsenic compound under study.

This article discusses the spectral dependences of the absorption coefficient of thin arsenic sulphide films obtained by spin-coating, identified using a single-beam spectrophotometer in the wavelength range of 400–1000 nm. The effect of doping of molybdenum on the optical band gap is studied. While for a pure glass the band gap decreases with higher sulphur concentration, the opposite trend is observed in glass doped with molybdenum. Molybdenum doping also leads to an increase in Urbach energy. The obtained experimental curves are compared with theoretical ab-initio calculations.

The paper presents the results of an experimental study of the dielectric properties of a composite with a polymer matrix based on polyvinyl alcohol cyanoethyl ether (CEPVA) with a filler—ferroelectric barium titanate BaTiO3 modified with graphene nanoparticles. The behavior of frequency dependences of the components with complex permittivity and electrical modulus indicates the relaxation character of the dielectric polarization with the participation of polar formations of the functional components of the composite under study.

The paper presents the results of an experimental study of trilead tetraoxide Pb3O4 binder layers and their dielectric properties. The study revealed polarisation processes in low frequency range associated with structure peculiarities in the Pb3O4 compound. The study established the dependence of dielectric properties on temperature and frequency of the applied field. The complex dielectric response of layer samples was measured under various AC drive and DC bias conditions. The paper provides an explanation for the influence of the simultaneous AC and DC voltages on dipole and Maxwell–Wagner polarisation in Pb3O4. It is assumed that there is an impact of interfacial barriers in the polycrystalline structure. The paper discusses the role of lone pair (LP) electrons Pb2+ in polarisation properties of trilead tetraoxide compound.