White‐beam synchrotron topographic characterization of antiparallel 180° domains in MgO doped near‐stoichiometric LiNbO₃

Abstract The Czochralski grown MgO‐doped near‐stoichiometric LiNbO₃ (N‐SLN) crystals have been investigated by using white‐beam synchrotron radiation topography. It was found that quasi‐periodic antiparallel 180° domains appeared frequently in y ‐cut (10$ \bar 1 $0) slice. Due to the different structure factors between positive and negative domains, at the wavelengths near the absorption edge of Nb atom, antiparallel 180° domains in MgO‐doped N‐SLN were revealed by anomalous scattering and the domain boundaries were visible by black‐white contrast from positive and negative domains. In the case of occurrence of anomalous scattering the ratio of |F (0006)|² to |F (000$ \bar 6 $)|² was calculated. The mechanisms of this quasi‐periodic domain inversion and the growth characteristics in MgO‐doped N‐SLN are also discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)