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The metallic ternary compound phase of S-P-H material is predicted to be the ground-state structure by first-principles cluster expansion. We find that the S0.75P0.25H3, S0.5P0.5H3, and S0.25P0.75H3 structures are thermodynamically stable. The characteristic of phonon dispersions shows that the S0.75P0.25H3 and S0.5P0.5H3 structures are dynamically stable at 200 GPa. The solution of the Fermi surface supports the values of superconducting transition temperature (Tc). In addition, the electron localization function and the projected crystal orbital Hamilton populations reveal that the nature of chemical bonding shows the degree of covalent bonding of the S0.75P0.25H3 and S0.5P0.5H3 structures, supporting the Tc value. Our results show that the S0.5P0.5H3 structure is the highest Tc among the S-P-H system. The Tc of the S0.5P0.5H3 structure is estimated to be 89 K at 200 GPa.

The metallic ternary compound phase of S-P-H material is predicted to be the ground-state structure by first principles cluster expansion. We find that the S0.75P0.25H3, S0.5P0.5H3, and S0.25P0.75H3 structures are thermodynamically stable. The characteristic of phonon dispersions shows that the S0.75P0.25H3 and S0.5P0.5H3 structures are dynamically stable at 200 GPa. The solution of the Fermi surface supports the values of superconducting transition temperature (Tc). In addition, the electron localization function and the projected crystal orbital Hamilton populations reveal that the nature of chemical bonding shows the degree of covalent bonding of the S0.75P0.25H3 and S0.5P0.5H3 structures, supporting the Tc value. Our results show that the S0.5P0.5H3 structure is the highest Tc among the S-P-H system. The Tc of the S0.5P0.5H3 structure is estimated to be 89 K at 200 GPa., QC 20210323

Semiconductor nanowires are versatile building blocks for optoelectronic devices, in part because nanowires offer an increased freedom in material design due to relaxed constraints on lattice matching during the epitaxial growth. This enables the growth of ternary alloy nanowires in which the bandgap is tunable over a large energy range, desirable for optoelectronic devices. However, little is known about the effects of doping in the ternary nanowire materials, a prerequisite for applications. Here we present a study of p-doping of InxGa1-xP nanowires and show that the growth dynamics are strongly affected when diethylzinc is used as a dopant precursor. Specifically, using in situ optical reflectometry and high-resolution transmission electron microscopy we show that the doping results in a smaller nanowire diameter, a more predominant zincblende crystal structure, a more Ga-rich composition, and an increased axial growth rate. We attribute these effects to changes in seed particle wetting angle and increased TMGa pyrolysis efficiency upon introducing diethylzinc. Lastly, we demonstrate degenerate p-doping levels in InxGa1-xP nanowires by the realization of an Esaki tunnel diode. Our findings provide insights into the growth dynamics of ternary alloy nanowires during doping, thus potentially enabling the realization of such nanowires with high compositional homogeneity and controlled doping for high-performance optoelectronics devices.

In order to estimate a diffusion coefficient, an InAs mole fraction profile, which is obtained by numerical simulation, is compared with a profile, which is experimentally obtained. The simulation result agrees well with the experimentally obtained profile. The diffusion coefficient is estimated to be about 1.1 x 10(exp -4) sq cm per sec by comparing the numerically obtained growth length with the experimentally obtained one., JAXA Research and Development Report, 宇宙航空研究開発機構研究開発報告

In order to investigate the two-dimensionality in the traveling liquidus-zone (TLZ) method, the two-dimensional TLZ model is introduced. Basing on the two-dimensional model, the two-dimensionality is defined. From the numerical results in various sample diameters, the two-dimensionality is obtained. In the case of the sample diameter of 2 mm, the two-dimensionality is negligibly small on the ground. However, in the case of 10 mm, the two-dimensionality is large even though under no gravity condition if an InGaAS Seed is used., JAXA Research and Development Report, 宇宙航空研究開発機構研究開発報告

We have performed a comparative study of optical properties of isostructural beta -FeSi2, OsSi2, and two ternary configurations of (FeOs)Si-2 by first-principle calculations of band structure and the imaginary part of the dielectric Function. The latter for beta -FeSi2 and OsSi2 were compared to those deduced from ellipsometric measurements: indicating an excellent agreement. From theoretical calculations both binaries are found to be indirect gap semiconductors, whereas one ternary is characterised by a direct transition with high oscillator strength. (C) 2001 Elsevier Science B.V. All rights reserved.

We have previously reported that ternary metal nitrides of the general composition CaxMyNz, where M is a transition metal or post transition metal, are readily prepared as polycrystalline powders by reaction of Ca3N2 and M under N2 at temperatures on the order of 100 C. When the structures are relatively simple, we have been able to determine the structures by x-ray or neutron powder diffraction. In only a few instances have we obtained single crystals. In order to prepare single crystals of materials with more complicated structures, we have been attempting to develop general methods of nitride crystal growth using molten salts or metal fluxes.