Optical pattern transitions from modulation to transverse instabilities in photorefractive crystals.
We show by experimental measurements and theoretical analyses that there exists a pattern transition from optical modulation instability to transverse instability in nonlinear media. An input coherent beam propagating in the photorefractive crystals is observed to break up into stripe filaments at a first threshold voltage. By modeling the periodic strip filaments as cnoidal waves, we demonstrate that a second threshold voltage for forming dot filaments comes from the transverse instability, resulting in a good agreement with the experimental data.
Jeng
Chien-Chung
CC
Department of Physics, National Chung-Hsing University, Taichung 402, Taiwan.
Lin
YuanYao
Y
Hong
Ray-Ching
RC
Lee
Ray-Kuang
RK