CORRELATION BETWEEN IMPURITY DISTRIBUTION AND LOCATION OF FERROELECTRIC DOMAIN-WALLS IN ND-MG-LINBO3 SINGLE-CRYSTAL

Using selective chemical etching, scanning electron microscope (SEM) a nd wave dispersive X-ray (WDX) microanalysis we showed that the ferroe lectric domain walls coincide with the maxima and minima Nd-impurity m odulation in a periodically poled Nd:Mg:LiNbO3 crystal grown bg the Cz ochralski method along the normal Lo the (0 1 (1) over bar 2)face, Asy mmetric form of the Nd-modulation produces nonequal positive and negat ive domains for one period. Variations of instantaneous rate of growth were estimated for facet and nonfacet crystal region in the framework of Burton-Prim-Slichter theory. (C) 1998 Elsevier Science B.V. All ri ghts reserved.