Bulk PPKTP by crystal growth from high temperature solution

Alexandra Pena (1) , Bertrand Ménaert (2) , Benoit Boulanger (1) , Fredrik Laurell (3) , Carlota Canalias (4) , Valdas Pasiskevicius (4) , Luc Ortega (5) , Patricia Segonds (1) , Jerome Debray (2) , Corinne Felix (6)

1 NEEL - OPTIMA - Optique et Matériaux
2 NEEL - CrisMass - Cristaux massifs
3 Laser Physics-KTH
4 KTH - KTH Royal Institute of Technology [Stockholm]
5 NEEL - X'Press - X'Press : diffraction et hautes pressions
6 NEEL - POM - Optique & Microscopies

Periodically-poled ferroelectric crystals show unprecedented efficiency and properties otherwise impossible to obtain. Unfortunately, the sample thickness obtainable today limits their use to low and moderate power application. With the aim of increasing the size of periodically domain-structured crystals with a controlled and regular grating period, we proposed an epitaxial growth process using seeds made of thin plates domain engineered by electric field poling. We demonstrated this process with the ferroelectric crystal KTiOPO4 (KTP) which is one of the most promising candidate materials for that purpose. The poling step requires a sample exhibiting (001) and (00 (1) over bar) faces, so that the growth step has to be performed onto these faces. This constraint is a difficulty to circumvent as these faces are not present in the standard equilibrium morphology. It is then necessary to find the growth conditions enabling to work below the roughening temperature of these faces. By using a high temperature solution method, the so-called "flux method", and by choosing an appropriate chemical composition of the flux solution, we obtained periodically domain-structured KTP layers with thicknesses up to 800 mu m and regular periodicity onto (001) and (00 (1) over bar) faces of the initial PPKTP seeds.

Mots clés: Growth from high temperature solutions; Liquid phase epitaxy; Ferroelectric materials; Nonlinear optic materials

Domaines: Optique [physics.optics]; Matériaux

Alexandra Pena, Bertrand Ménaert, Benoit Boulanger, Fredrik Laurell, Carlota Canalias, et al.. Bulk PPKTP by crystal growth from high temperature solution. Journal of Crystal Growth, 2012, 360, pp.52. ⟨10.1016/j.jcrysgro.2011.11.081⟩. ⟨hal-00909135⟩