Pavel V. Yezhov

Organic–inorganic photocurable nanocomposite materials are a topic of intensive research nowadays. The wide variety of materials and flexibility of their characteristics provide more freedom to design optical elements for light and neutron optics and holographic sensors. We propose a new strategy of nanocomposite application for fabricating resonant waveguide structures (RWS), whose working principle is based on optical waveguide resonance. Due to their resonant properties, RWS can be used as active tunable filters, refractive index (RI) sensors, near-field enhancers for spectroscopy, non-linear optics, etc. Our original photocurable organic–inorganic nanocomposite was used as a material for RWS. Unlike known waveguide structures with corrugated surfaces, we investigated the waveguide gratings with the volume modulation of the RI fabricated by a holographic method that enables large-size structures with high homogeneity. In order to produce thin photosensitive waveguide layers for their subsequent holographic structuring, a special compression method was developed. The resonant and sensing properties of new resonant structures were experimentally examined. The volume waveguide gratings demonstrate narrow resonant peaks with a bandwidth less than 0.012 nm. The Q-factor exceeds 50,000. The sensor based on waveguide volume grating provides detection of a minimal RI change of 1 × 10⁻⁴ RIU. Here we also present the new theoretical model that is used for analysis and design of developed RWS. Based on the proposed model, fairly simple analytical relationships between the parameters characterizing the sensor were obtained.

Nanocomposites based on transparent polymer matrices containing nanoparticles (NPs) of noble metals are modern-day materials that can be specially designed for photonics, linear and nonlinear optics, laser physics and sensing applications. We present the improved photosensitive nanocomposites doped with Au and Ag NPs allowing fabrication of high effective submicrometer dimensional diffraction structures using holographic method. A general approach for the fabrication of holographic structures using a two-component mixture of the monomers of different reactivity was developed. Two different methods, ex situ and in situ, were studied to introduce Au and Ag NPs in the polymer matrix. The diffusion model of the grating formation upon holographic exposure as well as the process of Ag NP synthesis in a polymer matrix is considered. The influence of the NP size on the polymerization process, material dynamic range and nonlinear properties were investigated. The mechanisms and characteristics of the nanocomposite nonlinear optical response are discussed.

We investigated the dynamics of electron excitations in plasmonic nanocomposite based on a polymer matrix with a periodic substructure of ordered silver nanoparticles. The nanoparticles were synthesized in the polymer matrix from a metal precursor periodically distributed by holographic method.

Method of Synthesized Phase Objects in the Optical Pattern Recognition Problem | InTechOpen, Published on: 2016-12-14. Authors: Pavel V. Yezhov, Alexander P. Ostroukh, Jin-Tae Kim, et

As a result of optical experiments, it is established that the controlled variation of a recognition sensitivity at the comparison of the input and reference objects can be realized, while solving the recognition task within the method of synthesized phase objects,1 as distinct from the standard approach. We have obtained and analyzed the results of the recognition for a collection of objects with the use a joint Fourier-transform correlator. For each of the objects, we studied the character of the signal amplitude decrease depending on the growth of distortions in the object structure. We show that it is possible to obtain a family of cross-correlation curves that decrease differently within the method of synthesized phase objects, rather than a single curve. This allows one to vary the sensitivity of the correlator in the process of recognition.