X-ray topographic investigation of tungstate flux-grown KTiOAsO4 crystals

Abstract

White-beam synchrotron radiation and Lang topographic investigations of non-linear optical crystal KTiOAsO4 have been car¡ out. It is shown that domains and growth striations are primary planar defects in tungstate flux-grown single crystals. By selecting the wavelength to activate anomalous scattering effect near the absorption edge of the As atom, antiparallel ferroelectric domains are revealed, and in reflection pairs hkl and hkl, the domains demonstrate contrast reversal. The differences in integrated intensity from a pair of opposite domains are also calculated and the harmonics in a Laue spot are given. Finally, the domain wall configurations are discussed in terms of the structural characteristics of KTiOAs04.