White-beam synchrotron topographic study of antiparallel 180° domains in near-stoichiometric LiNbO3 grown from Li2O-rich melt

A near-stoichiometric LiNbO3 (N-SLN) single crystal has been grown by a Czochralski method from a melt of 58.5 mol% Li2O composition. The N-SLN single crystal has been studied by white-beam synchrotron radiation topography. Due to the different structure factors between positive and negative domains at the reflection wavelength near the absorption edge of Nb atom, antiparallel 180° domains in N-SLN have been observed by anomalous scattering. The domain boundary is visible by black-white contrast from positive and negative domain and the ratio of |F(0006)|2 to |F(0006¯)|2 is calculated.