酸化物系フラックスを用いたSr_0.5Ba_0.5Nb₂O₆単結晶の育成

抄録

Sr_0.5Ba_0.5Nb₂O₆ (SBN) single crystal with various oxide fluxes was grown by flux cooling method. The results were as follows.
(1) SBN single crystal was only grown in binary of SrB₄O₇-BaB₄O₇ flux. The maximum size of the obtained SBN single crystal was over 1mm.
(2) The SBN single crystal obtained in binary flux had following properties. Curie point was 95°C. Electric resistivity was 3.0×10⁸Ω⋅cm at room temperature. Activation energy was 0.97eV in ferroelectric phase and 0.16eV in paraelectric phase.
(3) From additive of MgO in binary flux, SBN single crystal was changed to colorless and transparent. For the lattice constant, a axis was increased but c axis was decreased in dependence on amount of added MgO. Electric resistivity of the MgO doped SBN crystal was higher value than that of the MgO undoped SBN crystal.
(4) SBN single crystal was not grown in respective simple oxide fluxes. Pb₅Nb₄O₁₅ crystal was formed in PbO flux. Ba₃Nb₁₀O₂₈ and Sr₂Nb₂O₇ crystals were formed in CuO flux. Na_0.5Sr_0.25NbO₃ crystal was formed in Na₂B₄O₇ flux.