Growth and characterization of near stoichiometric LiNbO3 single crystal

A near stoichiometric LiNbO₃ single crystal has been grown by the Czochralski method from a 58.5% Li melt hold in a large platinum crucible. High resolution X‐ray rocking curves of 30 0 and 0006 reflections indicated that the near stoichiometric LiNbO₃ crystal possesses the high structural quality. Compared with the congruent LiNbO₃, the near stoichiometric LiNbO₃ possesses shorter ultraviolet absorption edge, thus higher Li concentration. The OH^– infrared absorption band analyses showed that the Li concentration in the near stoichiometric LiNbO₃ crystal is higher than that in the congruent LiNbO₃ crystal. This result is in good agreement with that of the ultraviolet absorption edge. The electro‐optic (EO) coefficient γ₂₂ of the near stoichiometric LiNbO₃ crystal was measured to be 6.75 pm/V higher than that of congruent LiNbO₃ crystal. It also proves the near stoichiometric LiNbO₃ electro‐optic Q‐switched requires a low driving voltage and it is advantageous for the device performance. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)