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Abstract: Growth of trivalent ions (La3+ and Nd3+) doped Bi4Ti3O12 (BIT) single crystal by self-flux method using excess Bi2O3 as flux is reported. The effects of trivalent ions on the structural, thermal, optical and ferroelectric properties of BIT crystal were investigated. The results of X-ray diffraction and thermal analysis, respectively, indicate that the lattice distortion, liquidus/crystallization temperatures of BIT considerably increase with La and Nd concentrations. Substitution of La in Bi3+ shifts the lower absorption edge towards the ultra-violet region (∼20–25nm), while no shift is observed for the BIT:Nd crystal. Regardless of the dopants, the optical microscopy patterns of the crystal surfaces reveal the existence of 90° domains. Dielectric measurements indicate that BIT:Nd crystals exhibit no significant variation in Curie temperature (T C) of BIT. Substitution of La and Nd in BIT increase both the remnant polarization (P r) and coercive field (E c) of BIT crystals. [Copyright &y& Elsevier]

Single crystals of magnesium diboride with maximum dimension of 200×200×60 μm3 have been successfully grown from copper flux in iron capsules. MgB2 crystallized separately in a system with the composition Mg40Cu40B20, and large single crystals were grown. Crystals grow together in the system with the composition Mg35Cu40B25, and MgB4 is found in this system due to excess B content. MgB2 crystallizes in very small particles in a system with the composition Mg50Cu40B10. MgB2 single crystals show strongly polarized light properties, and thus are easily discriminated from other kinds of accompanying crystals and from their surroundings. Magneto-optical microscope gives direct evidence of superconducting properties of MgB2 crystals. Further measurements of ac-susceptibility show that crystals begin the superconducting transition at 39.1 K with a transition width of 1.3 K. [Copyright &y& Elsevier]

Abstract: KNbO3 crystal is an incongruent melting crystal from a peritectic system. At first, a crystal was formed from the molten zone center of the stoichiometric composition using our original modified floating zone technique. Then the crystal was grown continuously using the firstly formed crystal as seed crystal. A small crystal with facets could be grown. The phase of the grown crystal was investigated in comparison to the phase grown by the conventional floating zone technique. [Copyright &y& Elsevier]

Abstract: Potassium niobate crystals were grown from high temperature solutions using the floating zone pulling-down technique. The starting solution compositions of K and Nb were changed from K:Nb=50:50 to 58:42. The lattice parameter, lattice volume and phase transformation temperature depended on the starting solution compositions. The solid solution region near the KNbO3 crystals was estimated to be expanding to a K-rich composition. [Copyright &y& Elsevier]