Periodic domain inversion in poled KTiOPO₄ via high-resolution x-ray topography and diffraction-space mapping

Periodic domain inversion produced by electron beam writing on the C- face of a hydrothermally grown KTiOPO4 crystal has been investigated by high-resolution multiple-crystal topography and diffraction-space mapping. Periodic contrast, with spacings which are consistent with the lateral dimensions of the inversion domains, has been observed by choosing a high spatial resolution mode for topography. Via reciprocal-space mapping, the scattering features along Δq∥ and Δq⊥ have been extracted and shown, by combination with high angular resolution topography, to relate to the lattice tilting and strain induced during the domain inversion process. The origins of the diffraction contrast in the domain inverted regions, and the factors affecting the diffraction images of the domains are discussed.