The Sanhetun tellurium-gold (Te-Au) deposit, located in the Duobaoshan polymetallic metallogenic belt (DPMB) within the eastern section of the Central Asian Orogenic Belt (CAOB), is a newly discovered small scale gold deposit. The mineralization, with resource of ≥ 4t Au, is mainly hosted in 3 NNE-trending alteration zones between granitic mylonite and volcanogenic-sedimentary formations. It’s the genesis and timing of formation of this deposit are poorly constrained. Here, we report the results of petrographic studies, TESCAN Integrated Mineral Analyzer (TIMA), major and trace element concentrations, and in situ S isotope of pyrite and U-Pb ages of calcite. The results show that there are five species of telluride, including native tellurium, tetradymite, tsumoite, hessite and petzite and four types of pyrite, including coarse-grained euhedral Py1, fine-grained quartz-Py2 vein crosscutting Py1 and anhedral aggregated Py3 and Py4. The pre-ore Py1, containing negligible Au, Te and other trace elements, have a relatively narrow range of δ34S values ranging from -1.20 to -0.57‰. The Py2 have slightly high concentrations of Au and Te and distinctly high concentrations of Mo, Sb, Zn and Mn with markedly positive δ34S values of 4.67 to 14.43‰. The main ore stage Py3 contains high Au and Te concentrations and shows narrow δ34S values ranging from -5.69 to 0.19‰. The post-ore stage Py4 contains low Au concentrations with the δ34S values ranging from 2.66 to 3.86‰. Calcite from ore stage yield a U-Pb age of 135 ± 22 Ma, interpreted as the age of Te-Au mineralization. Our geochemical and geochronological data indicate that the Te was derived from partial melting of mantle metasomatized by the Te-rich fluids that originated from oceanic sediments. We correlate the tectonic setting with the subduction of Paleo Pacific plate in Early Cretaceous.

The problem of intensification of melt crystal growth process has been analyzed using CdTe as an actual material. Numerical simulation of 100 mm diameter CdTe crystal growth by VGF technique has been carried out. The heat-mass transfer was controlled by introducing of low-frequency oscillating baffle into the melt, so called axial vibrational control (AVC) technique. The baffle configuration has been optimized to destroy solid «tails», which were formed near the crucible walls at high cooling rates due to the low thermoconductivity and the corresponding latent heat. Analysis of CdTe homogeneity range showed that during fast crystal cooling Te micro precipitations were formed resulting from decay of oversaturated Cd-riched nonstoichiometric solid solution at Bridgman crystal growth technique. A VGF grown CdTe crystal after full crystallization stays inside the phase field of the high temperature wurtzite polymorph. This makes it possible to go through the polymorph transition without Te micro-precipitating using the advantages of VGF specific feature of very slow cooling.

In this study, the effect of laser processing (LP) on the thermoelectric (TE) properties of bismuth antimony telluride (BST) alloy pellets is investigated. The stoichiometric alloy used is Bi0.4Sb1.6Te3.0, which was prepared by mechanical alloying techniques (MA) and hot pressed (HP) into pellets under optimal pressing and temperature conditions. An innovative approach to HP was also developed to enhance the yield of BST samples per HP process while maintaining the TE profiles of the samples within a variance of less than 1%. The LP process was executed by employing a metal 3D printer, with a thorough analysis of beam parameters. Notably, the laser power (P) was held constant at 25 W, along with a fixed hatching distance (HD) of 50 μm, while the parameter adjusted was the laser's scanning speed (SS), which spanned from [600 - 1800] mm/s in increments of 200 mm/s. Examination via scanning electron microscopy (SEM) revealed two material states: melted and sintered. The melted state formed the surface crust of "canyon" patterns that were held on the surface of the samples, and which both size and quantity were altered with changes in SS. For thermoelectric characterization, two distinct shapes of LP samples were produced: rectangular (for electrical properties) and disk (for thermal properties). The results demonstrated that the electrical properties are profoundly influenced by SS, with the electrical conductivity peak at SS value of 1600 mm/s, while the Seebeck coefficient reaches a minimum at the same value. Consequently, within the temperature range of interest, a notable 12% increase in electrical conductivity and a 9% decrease in the Seebeck coefficient were observed compared to the non-LP material state. Overall, the ZT value experience an 6.9% decline within the same temperature interval.

We report on comparison between temperature-dependent magneto¬absorption and magnetotransport spectroscopy of HgTe/CdHgTe quantum wells in terms of detection of phase transition between topological insulator and band insulator states. Our results demonstrate that temperature-dependent magnetospectroscopy is a powerful tool to discriminate trivial and topological insulator phases, yet magnetotransport method is shown to have advantages for clear manifestation of the phase transition with accurate quantitative values of transition parameter (i.e. critical magnetic field Bc).

In this work, the parameters of plasma (electron temperature (T_e), electron density n_e, plasma frequency (f_p) , Debye length (λ_D) and Debye number (N_D)) have been studied by using the spectrometer that collect the spectrum of Laser produce Cadmium telluride plasma at different energies. The results of electron temperature for CdTe range 0.93-1.18 eV also the electron density 5 × 10¹⁰ – 3.8 × 10¹¹ cm^-3 have been measured under vacuum reaching 2.5 × 10^-2 mbar .Optical properties of CdTe were determined through the optical transmission method using ultraviolet visible spectrophotometer within the range 190 – 1100 nm.

The interest in the Spark Plasma Sintering (SPS) technique has continuously increased over the last few years. This article shows the possibility of the development of a SPS device used for material processing and synthesis both in both scientific and industrial applications. This work presents an example of processing Arc-Meleted (half-Heusler, cobalt triantimonide) and SHS-synthesized semiconductors (bismuth telluride) materials with SPS device. The system functionalities expansion is presented, showing the possible way of increasing the information amount obtained about SPS processes and using the SPS apparatus for conducting synthesis of materials and increasing reproducibility and accuracy of process parameters control.