Sergey N. Sharangovich

Investigation of influence of photopolymerization processes on kinetics of transmission and reflection gratings record in absorbent photopolymer materials

In this paper we present the model of record of 3-dimensional transmission and reflection gratings for 0.3<k<1 (k - exponent of intensity in photopolymerization equations) in photopolymers with a dye sensitizer. The numerical simulation of kinetics of transmission and reflection gratings record in this kind of photopolymers and its diffraction performances for optional value of k and contrast are carried out on the base of the model. The model also takes into consideration the following factors: polymerization and diffusion mechanisms of record, optical absorption, contrast of interference pattern, change of diffusion coefficients during record according polymerization level.

Analysis of dynamics of holographic grating formation with inharmonic spatial distribution in photopolymer + liquid crystal compounds

We present an analytical model of dynamics of three spatial harmonics of 2D spatial grating profiles with taking into consideration both record mechanisms (polymerization and components diffusion, absorption, interference pattern contrast. On the base of numerical simulation we examined an influence of these parameters on 2D spatial profile along grating vector and along thickness of a film.

The PDLC photonic structures diffraction characteristics managing by the spatially non-uniform electric field

We develop an analytical model of light beams diffraction on the holographic photonic PDLC structures under the influence of a spatially non-uniform electric field. We propose an additional way to control the diffraction characteristics of these structures.

Anisotropic light beam diffraction on electrical controlled holographic gratings in photopolymer-dispersed liquid crystals

In this work we present the analytical model of light beam diffraction on holographic recorded polymer-dispersed liquid crystals anisotropic gratings controlled by an electrical field and their diffraction properties investigation. Optical anisotropy, statistics of LC orientation distribution in the droplet, optical nonuniformity of PDLC layer caused by reorientation of the mean values of principal axes of liquid crystal droplets in the homogeneous electrical field, photopolymeric and liquid crystalline components of diffraction structures are taken into consideration.

Analysis of kinetics of photopolymer holographic grating formation with inharmonic spatial distribution

We present an analytical model of dynamics of three spatial harmonics of 2D spatial grating profiles with taking into consideration both record mechanisms (polymerization and components diffusion), absorption, interference pattern contrast. On the base of numerical simulation we examined an influence of these parameters on 2D spatial profile along grating vector and along thickness of a film

Formation of Holographic Transmission Diffraction Gratings in Absorbing Photopolymer Media

The formation of holographic transmission gratings in absorbent photopolymer materials (PPM) is studied theoretically. Analytical model describing a spatiotemporal transformation of holographic grating field during record is developed with allowance for optical absorption and diffusion processes. It is demonstrated that optical attenuation during record causes the spatial inhomogeneity of refractive index grating profile and of the its growth kinetics. A degree of influence of optical attenuation on the integral diffraction characteristics is evaluated based on numerical simulation. The kinetics of record of high-efficient transmission holograms in PPM is experimentally investigated. Based on a comparison of theoretical and experimental time dependences of diffraction efficiency, physical parameters of the examined PPM are determined and adequacy and tendency in the development of the suggested mathematical model are evaluated.

Nonuniform holographic photonic structures in photopolymer-based nano-composites

In the paper we present the analytical model of multi-beam record of photonic structures in photopolymer composite materials. In the model the photonic structures considered as superposition of superimposed diffraction gratings with arbitrary number of harmonics. The model takes into account nonuniform intensity distribution of beams recorded, nonlinearity of record process, and absorption of material. The results of numerical simulation of influence of interrelation between harmonics and gratings and nonlinearity of record process on photonic structure characteristics are presented. The simulation has been carried out on the base of the model presented.

Analytical and experimental investigations of nonlinear dynamics of photopolymer Bragg gratings at pulse recording

In this paper, the analytical models of pulse record of diffraction gratings in photopolymer material (PPM) are presented. In the analytical model we take into consideration that record process is realized with optical pulse string. The model is developed for transmitted gratings recorded at photoinduced optical absorption. The diffraction efficiency of gratings has been calculated on the base of the analytical model. The experimental investigations of pulse recording have been carried out in HPPM-630 photopolymer material. The matching of data calculated theoretically and experimental data have been made.

Anisotropic interaction of light beams with electrically controlled nonuniform holographic polymer-dispersed liquid crystals transmission gratings

In this work we present the analytical model of anisotropic light beam diffraction on holographic recorded polymer-dispersed liquid crystals transmitted gratings controlled by an electrical field and their diffraction properties investigation.

Analytical and experimental investigations of photopolymer Bragg gratings at a string pulse record

In this work the theoretical study of pulse string construction of holographic gratings in photopolymeric materials with light-induced optical attenuation has been carried out. The analytical model describing spatial-temporal transformation of holographic grating field during construction process is developed. The model has a view of recurrence relation and takes into consideration light-induced changing of optical attenuation and diffusion process. The results of numerical simulation on the base of the model are presented and include analysis of record stage, self-amplification stage and whole pulse string construction. The behavior of spatial profile and diffraction characteristics of constructed gratings are estimated with the help of numerical simulation. Fitting experiment and theoretical data has been made. The researched photopolymer was made in Institute of Organic Chemistry of the Siberian Separation of the Russian Academy of Sciences (Novosibirsk).