Phase relations in the growth of stoichiometric LiNbO3
|Katalin Polgar 1, Ágnes Péter 1, Michel Ferriol 2|
1. Hungarian Academy of Sciences, Research Institute for Solid State Physics and Optics (SZFKI), Konkoly Thege M. út 29-33, Budapest H-1121, Hungary
LiNbO3 is one of the most common perovskite-type crystals for optical applications. This a typical non stoichiometric material melts congruently at 48.6 mol % Li2O content and can be grown easily by Czochralski method from its melt. The congruent composition is a serious drawback causing a defect structure with about 1% anti-site Nb5+ ions in the lattice. Therefore stoichiometric crystals (50 mol % Li2O) are expected to show improved performance for a number of applications. In this structure the amount of anti-site Nb5+ is below 0.001%which results in the blue shift of the UV absorption edge, the narrowing of several spectral lines (EPR, NMR, Raman, IR OH- vibration lines , Cr3+luminescent line of the doped crystal.) An important reduction of the electric field (200 V instead of 2kV) required for ferroelectric domain inversion in the stoichiometric crystal makes easier the production of periodically polarized structures for quasi-phase matching.
Presentation: invited oral at E-MRS Fall Meeting 2003, Symposium A, by Katalin Polgar
See On-line Journal of E-MRS Fall Meeting 2003
Submitted: 2003-05-26 14:11 Revised: 2009-06-08 12:55