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In this paper, we report the conditions and results of the synthesis of solid solutions and flux growth of single crystals with the general formula La1 −x–yTbxEuyMgB5O10 from a K2Mo3O10-based high-temperature solution. The structural properties, composition, thermal characteristics, Tb3+ and Eu3+ luminescence spectra, and excitation spectra of the solid solutions have been studied in the ranges 0.2 < x < 0.7 and 0.1 < y < 0.6. We have calculated CIE luminescence spectra of the single crystals and fabricated operating prototype emitters using them. [ABSTRACT FROM AUTHOR]

The paper presents a flux crystal growth technique, studies of the structural peculiarities and the optical absorption spectra of double orthoborate TbCr3(BO3)4 with a huntite structure. The intensities of the phonon modes were used to determine the ratios of the rhombohedral and monoclinic polytypes for this compound, depending on the growth conditions. The broadband absorption spectra of the Tb3+ ions in TbCr3(BO3)4 single crystals were studied in the temperature range from room temperature to 3.0 K. From them, the energies of the crystal-field levels of the Tb3+ ion were determined. The temperature dependence of the absorption spectra of the Er3+ probe ion in TbCr3(BO3)4:Er(1%) shows that there are two phase transitions and agrees with their previously proposed interpretation: at 8.8 K, the chromium subsystem antiferromagnetically orders, and at 5 K, a reorientation of chromium magnetic moments occurs. [ABSTRACT FROM AUTHOR]

The spectral-luminescent properties of Er3+,Yb3+:YMgB5O10 were investigated. The spectra of the cross section of absorption and stimulated emission in polarized light were determined. The lifetimes of the erbium 4I13/2 and ytterbium 2F5/2 energy levels were measured. The Yb3+ → Er3+ energy transfer efficiency was estimated. Within the framework of the conventional Judd–Ofelt theory the strengths of absorption and emission transitions were calculated, which made it possible to determine the lifetime of the Er3+ excited energy levels as well as the luminescence branching ratios. [ABSTRACT FROM AUTHOR]

We have studied and optimized conditions for spontaneous flux growth of TbCr3(BO3)4 crystals. Phase relations in the pseudoternary system TbCr3(BO3)4–K2Mo3O10–B2O3 have been studied in the temperature range 900–1130°C and the single-phase terbium chromium borate crystallization field has been mapped out. It has been shown that increasing the TbCr3(BO3)4 content of the starting high-temperature solution leads to a rhombohedral-to-monoclinic phase transition. Using K2Mo3O10-based high-temperature solutions, we have grown single-phase TbCr3(BO3)4 single crystals or crystals in which the rhombohedral phase (sp. gr. R32) significantly prevails over the monoclinic phase (sp. gr. C2/c). The grown crystals have been characterized by X-ray diffraction techniques, IR spectroscopy, and magnetic measurements. [ABSTRACT FROM AUTHOR]

The ideal of a "strong state" for economic development and provision of security has always been prevalent in Russian history, especially in nativist thought. This paper argues against this perspective by analyzing the stateless Bukhtarman stonemason communities of the eighteenth century that thrived outside of state control in the mountainous region near the Bukhtarma river. I show that through entrepreneurial freedom, free trade, norms for dispute resolution, and signaling through adoption of faith, these anarchic communities were able to avoid the Hobbesian war of all against all and substantially improve their economic welfare. [ABSTRACT FROM AUTHOR]