In this paper the analyses of the linear and nonlinear light propagation in the photonic crystal fiber infiltrated with nematic liquid crystal is presented. Our theoretical investigations, carried out by using the finite difference beam propagation method, show the extreme importance of the discrete space representation aspect. The main aim of this work is to reveal that application of the triangular grid for the discretization of the analyzed structure of the photonic crystal fiber with the hexagonal symmetry gives more reasonable results than in the case of the standard square mesh utilization.
In this work nonlinear light propagation in a photonic crystal fiber (PCF) infiltrated with a nematic liquid crystal
(NLC) is presented. Such a photonic structure, called the photonic liquid crystal fiber (PLCF), combines the passive PCF
and the active NLC guest mixture. The analyzed configuration with a periodic modulation of spatial refractive index
distribution corresponds to the matrix of waveguides. This kind of structure can be controlled by optical power and
additionally by temperature and it allows for studying variety of discrete optical phenomena. For properly chosen
parameters of the analyzed fiber, discrete diffraction in the linear case and generation of the discrete spatial soliton in
nonlinear regime can be obtained. In this paper a possibility of the transverse light localization and delocalization due to
both focusing and defocusing Kerr-type nonlinearity was analyzed. In the case of the positive nonlinearity the refractive
index increases as a function of light intensity in such a way that the stronger guiding of the light within NLC cores is
obtained. Light modifies the refractive index distribution inducing a defect in the periodic structure. That can lead to the
situation in which light becomes self-localized and its diffractive broadening is eliminated. Eventually the discrete
soliton can be created. In the case of negative nonlinearity, the difference between NLC waveguides and glass refractive
indices decreases and the beam guidance becomes weaker for higher light intensities. In such a case the generation of the
bright soliton is possible only in the regime of negative discrete diffraction. However, in the case of defocusing
nonlinearity a decrease of refractive index with the optical power can lead to the bandgap shifting. The incident beam
with a frequency initially within a bandgap is then turned outside the bandgap resulting in changing of the propagation
mechanism to the modified total internal reflection.
The article describes measurements and interpretations of transverse distribution of an underpressured nitrogen laser beam. Also there is a trial of visualization of a UV beam.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.