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Phase equilibria that are relevant for the growth of Bi2MO4 have been studied experimentally, and the ternary phase diagrams of Bi2O3–PdO2–Pd and Bi2O3–Cu2O–CuO and its isopleth section Bi2O3–CuO were redetermined. It is shown that every melting and crystallization process is always accompanied by a redox process at the phase boundary and that for both title compounds, the valence of the transition metal is lowered during melting. Vice versa, during crystal growth, O2 must be transported through the melt to the phase boundary. Based on these new insights provided by our thermodynamic studies, Bi2CuO4 single crystals with a length of up to 7 cm and a diameter of 6 mm were grown by the OFZ technique to be used for investigations of magnetic, electronic and thermal transport properties. The grown crystals were characterized by powder X-ray diffraction, Laue, magnetization and specific heat measurements. [ABSTRACT FROM AUTHOR]

Cylindrical SrTiO3 single crystals with diameters and lengths exceeding one inch were grown from non-stoichiometric melts below 1800 °C using the high temperature top-seeded solution growth (TSSG) method. Despite the large crystal diameter the quality has been improved compared to Verneuil grown crystals. Typical etch pit density (EPD) values are in the range between 2 × 104 and 2 × 105 cm−2 for bulk crystals pulled in the ＜100＞ direction and using seeds with EPD values of 5 × 105 cm−2. So far pulling SrTiO3 crystals from the melt suffers from growth instabilities like foot formation and subsequent spiraling. To avoid them an effective heat transport via the crystal is indispensable. Especially at elevated temperatures it requires a high optical transparency in the infrared region. In this paper we report the correlation between oxygen partial pressure, composition, IR-transmittance and coloration of the crystals. The growth at a sufficiently high oxygen partial pressure leads to an increase in the optical transparency of the crystals and can thereby suppress foot or spiral formation. [ABSTRACT FROM AUTHOR]

The TiO2 rich part of the (1 - x)SrO + xTiO2 phase diagram (0.5 ⩽ x ⩽ 1.0) was redetermined and the eutectic point between SrTiO3 and TiO2 was found at xeut = 0.7700 ± 0.0001; Teut = 1449 ± 3 °C. From TiO2 rich melt solutions, x = 0.75, centimeter-sized single crystals could be grown. The best crystals with an etch pit density of <2 × 104 cm-2 were obtained for growth directions (110) and (100). AFM investigation of the interface reveals layer-by-layer growth. [ABSTRACT FROM AUTHOR]