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[en] Single crystals of GeS were produced using the Bridgeman technique. The speed of lowering the quartz ampoule was between 0.8 and 10/ mm/h, with a temperature gradient between 10 and 20 k/cm. From X-ray analysis the lattice structural properties and the lattice constants were obtained. With a suitable etch dislocations were observed. The optical absorption has been studied and the optical indirect and direct allowed energy gaps obtained
[en] Directional solidification of CM247LC was performed at a constant growth velocity (300 mm/h) using a Bridgman type furnace. Microstructural features, including the number of grains, PDAS, and EBSD IPF map, were investigated with progressive positions from the starter block. As directional solidification proceeded, the number of grains decreased and PDAS increased. These results indicate that the thermal gradient decreases with distance from the starter block. Thermal gradient changes were estimated by dendrite spacing change in the directionally solidified rod. The EBSD IPF map showed that almost all of the grains were close to the <001> preferred direction, but with heights of about 300 mm from the starter block, some grains at the center of the specimen exhibited quite different crystallographic directions near the gate instead of the preferred direction.
[en] A new method of crystallization of cadmium telluride is described. The growth is carried out, by normal freezing of a tellurium-rich solution, in a vertical Bridgman furnace. Crystals of high purity (45mm in diameter-150mm in length) are obtained with this process
[en] Highlights: ► YCOB is a novel non-linear optical crystal possessing good thermal, mechanical and nonlinear optical properties. ► Large size crystal growth is key technology question for YCOB crystal. ► YCOB crystals 3 in. in diameter were grown with modified vertical Bridgman method. ► It is a more effective growth method to obtain large size and high quality YCOB crystal. -- Abstract: Large-aperture yttrium calcium oxyborate YCa4O(BO3)3 (YCOB) crystals with 3 in. in diameter were grown with modified vertical Bridgman method, and the large crystal plate (63 mm × 68 mm × 20 mm) was harvested for high-average power frequency conversion system. The crack, facet growth and spiral growth can be effectively controlled in the as-grown crystal, and Bridgman method displays more effective in obtain large size and high quality YCOB crystal plate than Czochralski technique.
[en] A process is described whereby crystals of an alkaline metal halide may be dried and placed in a crucible for development by the Bridgeman-Stockbarger method. Purified alkaline halides from a suspension are dried and formed into dense cakes of transverse section slightly smaller than that of the crucible, where they are packed, melted and grown into crystals according to the Bridgeman-Stockbarger technique. This method applies to the preparation of alkaline halide crystals, particularly sodium iodide for optical elements or scintillation counters
[fr]On decrit un procede de sechage et de mise en place de cristaux d'halogenure de metal alcalin dans un creuset en vue de leur developpement selon la methode de Bridgeman-Stockbarger. Les halogenures alcalins purifies provenant d'une suspension sont seches et transformes en gateaux denses de section transversale legerement inferieure a celle du creuset et ils sont entasses dans le creuset ou ils sont fondus et ou on les fait croitre pour en former des cristaux suivant la technique de Bridgeman-Stockbarger. Ceci est applicable a la preparation de cristaux d'halogenures alcalins, notamment d'iodure de sodium pour des elements optiques ou des compteurs a scintillation
[en] Recent advances in the growth and doping of CdZnTe using low-pressure Bridgman methods have allowed for the production of high-resistivity crystals. In this work, we present electrical characterization measurements on samples of CdZnTe grown at Washington State University. We demonstrate the capabilities of the CdZnTe material to perform as radiation detectors and correlate detector performance with crystal growth conditions
[en] FeIn2S2Se2 single crystals are grown for the first time by the Bridgman method, and their composition and properties are determined. It is found that the single crystals are hexagonal in structure. The arrangement of Fe ions in the structure of the FeIn2S2Se2 crystals is studied by nuclear γ-resonance spectroscopy. From the transmittance spectra in the region of the fundamental absorption edge, the band gap of the single crystals grown in the study is determined.