https://doi.org/10.1051/epjap:1999249
Focusing effect in X-ray diffraction imaging of LiNbO3 crystals under static electric field
1
European Synchrotron Radiation Facility, B.P. 220, 38043 Grenoble, France
2
Polish Academy of Sciences, Swietokrzyska 21, 00049 Warszawa, Poland
Corresponding author: rejma@esrf.fr
Received:
6
April
1999
Accepted:
12
October
1999
Published online: 15 December 1999
The X-ray diffracted intensity changes considerably when a static electric field is applied perpendicularly to a X- or Y-cut LiNbO3 platelet-shaped crystal. Section diffraction images (topographs) recorded using synchrotron radiation in transmission mode reveal the curvature of the lattice planes under such a field. A theoretical analysis based on the equations of electro-mechanical field in a piezoelectric medium together with chemical etching experiments allows us to explain this effect. Tiny inverted ferroelectric doMayns produced by the applied field exert a strain on the non-inverted bulk leading to the observed curvature of the lattice planes. This approach seems to be valid for other piezoelectric crystals of various symmetry classes.
PACS: 77.84.Dy – Niobates, titanates, tantalates, PZT ceramics, etc. / 61.10.-i – X-ray diffraction and scattering / 61.72.Ff – Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
© EDP Sciences, 1999
