J. Trull1, C. Cojocaru1,
R. Fischer2, S. M. Saltiel 2,3, W. Krolikovski 4,
K. Staliunas 1, R. Herrero1, Ramón
Vilaseca1, Yuri S. Kivshar2
1) Departament de Física i Enginyeria
Nuclear, Universitat Politècnica
de Catalunya, Terrassa,
2) Centre for Ultrahigh Bandwidth Devices for
Optical Systems (CUDOS),
Nonlinear Physics Centre,
3) Faculty of Physics,
4) Centre for Ultrahigh Bandwidth Devices for
Optical Systems (CUDOS),
Laser Physics Centre, Research School of Physical Sciences and
Engineering,
Australian National University, Canberra, Australia
Broadband second harmonic
parametric scattering in ferroelectric crystals with random domains
structure
Optical second-harmonic generation (SHG) in
material structures with some class of disorder is a subject of present
interest. We report the results of an experimental study on broadband
second-harmonic parametric scattering in an un-poled Strontium Barium
Niobate
(SBN) crystal with random ferroelectric domains. We consider different
geometries of the interacting waves. The observed spatial distribution
of the
SHG is due to the larger facility to achieve phase matching conditions
in the
presence of disorder, and the polarization of the SH light can be both
ordinary
and extraordinary. The nonlinear coefficients of the crystal may be
determined
from the measurement of the SHG as a function of the fundamental beams
polarization. The experimental results are in very good agreement with
the predictions
of our theoretical model.