Substitution of Aluminum and Gallium in Single-Crystal Yttrium Iron Garnets

Single crystals of yttrium iron garnet with substitutions of aluminum and gallium were grown from lead oxide-fluoride, lead borate, and barium borate fluxes. Crystals were grown both by slow cooling and by the gradient technique. The aluminum and gallium contents of these crystals were measured; the amount of substitution and its distribution in one crystal and in the mass of crystals in a run were determined. Crystals grown by slow cooling were badly segregated with respect to aluminum and gallium content whereas gradient-grown crystals were very uniform.