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The growth of Fe doped LiNbO3 single crystals by the Bridgman method had been reported. Large-size, 0.04 mol% Fe2O3 containing single crystals with good optical property were obtained under the optimum conditions: choosing proper raw materials, sealed platinum crucibles and convex or plane solid–liquid interface with a temperature gradient around 20–30 °C/cm, at the growth rate of 1–3 mm/h. X-ray diffraction (XRD) and differential thermal analysis (DTA) were used to characterize the single crystals. The UV–Visible spectra of lower and upper parts of the single crystals were measured and the Li and Fe concentrations in the crystals were analyzed by using inductively coupled plasma (ICP) spectrometry. The results indicated that the overall Fe and Fe2+ concentration in the single crystal slightly increased from lower to upper parts. The addition of small amount of Fe ions induced bigger lattice parameters. [Copyright &y& Elsevier]

The growth of LiNbO3 crystals by the modified Bridgman method has been reported. The feed material with accurate congruent melt composition is suitable to grow the crystals. Composition change of the melt during growth can be avoided by sealing platinum crucibles. Using the optimum conditions such as growth rate of 1–3 mm/h and temperature gradient around 30°C/cm across the solid–liquid interface, the congruent LiNbO3 crystals without macro-defects have been grown successfully. [Copyright &y& Elsevier]

The growth of novel birefringent crystal α-BaB2O4 by the modified Bridgman method has been reported in this paper. By means of the optimum conditions such as stoichiometric feed materials, sealed platinum crucibles, [001] growth direction, growth rate less than 0.3 mm/h and convex or plane solid–liquid interface with temperature gradient 30–40 °C/cm, large-size crystals without macro-defects have been grown successfully. [Copyright &y& Elsevier]

The growth of LiNbO3 single crystal doped with Eu3+ ions by the Bridgman method and the characteristics of temperature-dependent emission spectra were reported. By means of the optimized conditions such as proper raw materials, sealed platinum crucibles, growth rate of 1–3 mm h−1 and convex or plane solid–liquid interface with a temperature gradient around 20–30 °C cm−1, large size crystals containing 0.1 mol% Eu3+ ion with good optical quality were obtained. X-ray diffraction and DTA were used to characterize the crystals. The temperature-dependence emission spectra of lower and upper part of crystals from 77 to 600 K were investigated under the excitation of a 488 nm light. The results show that, for the upper part of crystal, the fluorescence intensity of Eu3+ ions increased with increasing the temperature as a whole. However, for the lower part, it first increased with increasing the temperature, and then decreased obviously with increasing the temperature. The variations of fluorescence intensity for the lower and upper parts of crystals were discussed. The decrease of emission intensity was induced by the temperature-quenching effect. [Copyright &y& Elsevier]