This PDF file contains the front matter associated with SPIE Proceedings Volume 9031, including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

In the initial variant, the recently proposed correlation-stability approach to elasticity mapping in optical coherence tomography (OCT) of tissues was intended for qualitative visualization of the relative stiffness of different regions in tissue. Further development of this approach is aimed at obtaining the stiffness ratio between different tissue regions. In the proposed modified variant, the correlation-stability approach has much in common with the speckle variance approach which is used for visualizing blood microcirculation in OCT. We present preliminary demonstrations of implementation of the modified correlation-stability approach to quantify the relative stiffness using processing of the speckle-structure variability of OCT images of deformed tissues.

PPG volumetric model is frequently adopted to explain the pulsatile nature of optical response for arterial pulsation. In this article we show that the pulsatile fluctuation of optical response can be explained in terms of the light scattering related changes. According to this assumption, these fluctuations are driven by the modulation the scattering coefficient associated with the blood flow hemodynamic effects. There was shown that the proposed model yields a good correspondence with the pulse-oximetry related parameters. Moreover, it was found that the experimental relationship between the red blood concentration in the blood (hematocrit) and the parameters being derived from the in vivo measured optical signals can be described in terms of this scattering driven model. There was demonstrated that the commonly used volumetric assumption fails to provide a reasonable description of the experimental results. The last fact can be used as a decisive argument in favor of the scattering driven model. This model can be used for better understanding of the pulse oximetry as well as for the guidance for the algorithmic development of the blood hemoglobin/ hematocrit in vivo.

We estimate a limit to spatial resolution in time-domain diffuse optical tomography (DOT) based on a perturbation model by Lyubimov. In the context of structure reconstruction accuracy we consider and compare three approaches to the inverse DOT problem. The first reconstructs diffuse tomograms from straight lines; the second does it from curvilinear average trajectories of photons; and the third uses the total banana-like distributions of photon trajectories. For getting estimates to resolution, we derive analytical expressions for the point spread function and the modulation transfer function, and perform a numerical experiment to reconstruct rectangular scattering objects with circular absorbing inhomogeneities. It is shown that reconstruction with photon trajectory distributions instead of straight lines gives a gain of about order of magnitude in resolution and attains the accuracy of multistep nonlinear DOT algorithms.

Method of optical polarimetry is well known, but earlier it was mainly used to low scattering media. In this paper we consider the possibility of measuring the glucose concentration by detecting polarization of the backscattered laser light. As object of research a human finger have been chosen. The optimal parameters of the probing light were identified, degree of polarization of light scattered by human skin and model objects was registered. A laboratory model of a differential polarimeter, which allows to register the parameters of the polarized radiation scattered by human skin and glucose containing models, was developed. Using the developed polarimeter, model and full-scale experiments were carried out. In the model experiments we investigated the light backscattered by the following objects: a 20% solution of milk and a 50% suspension of human blood. During experiments it was shown, that the amount of optical rotation is also dependent on the angle of registration and, hence, photodetectors position in space is important. The ability of the developed sensor to noninvasively detect the concentration of glucose in the blood was demonstrated. However, its sensitivity to the structure of human skin and the individual characteristics of the organism was identified. This suggests that in order to achieve maximum accuracy it is necessary to carry out individual adjustment and calibration of measuring equipment.

Unprompted skull bones mobility not related to breathing, heart beating and other physiological reactions, using installation of original construction with control of physiological parameters by biofeedback hardware-software complex BOS-lab and BOS-pulse appliance (COMSIB, Novosibirsk, Russia) has been confirmed. Teeth eruption occurs through odontiasis canals, emerging from the funiculus. The main driving force for promoting a tooth into odontiasis canal during eruption is the unprompted skull bones mobility. A simple optical installation was made for the visualization of skull bones mobility during the investigation of the median palatine and incisors sutures. Early detection of failures of unprompted skull bones mobility and its normalization can lead to prevention of impact teeth, malocclusion, extrudocclusion and other anomalies and deformations of teeth, teeth rows, TMJ and skull. The skull bones mobility should be considered during the early preventive treatment and therapy of the consequences of injuries and malfunction of the maxillofacial area.

A digital optical system for intravital capillaroscopy has been developed. It implements the particle image velocimetry (PIV) based approach for measurements of red blood cells velocity in individual capillary of human nailfold. We propose to use a digital real time stabilization technique for compensation of impact of involuntary movements of a finger on results of measurements. Image stabilization algorithm is based on correlation of feature tracking. The efficiency of designed image stabilization algorithm was experimentally demonstrated.

Application of thermometry as a method of blood flow estimation in hands is limited by the differences in waveform of the skin temperature and blood flow oscillations. In addition, there is the delay time between simultaneously registered blood flow and temperature signals. We offer the method of blood flow estimation in hands based on the analysis of skin temperature dynamics. Simplification of the Shitzer's temperature dynamics model in hands allowed us to express the relation between the temperature and blood flow oscillations. As it turns out, within using model the skin blood flow is proportionally to the first time derivative of the skin temperature, in other words, the blood flow oscillations determine the rate of skin temperature alterations. We also derived relation between spectral components of the blood flow and temperature oscillations. To extract spectrum of the blood flow oscillations from temperature spectrum it is necessary using frequency dependent multiplication factor and time shift of each of temperature spectral component. In this study the skin temperature was registered by infrared camera and blood flow was estimated by photoplethysmography. First time derivation of the temperature increases correlation between processed signal and blood flow oscillations from ~0.3 to ~0.7 on average. Thus, derived relations between temperature and blood flow in fingertips provide the basis for the application of thermometry in the field of analysis of low-frequency peripheral blood flow oscillations.

Methods t-LASCA and s-LASCA has been adopted for diagnostics of malignant tissue on animal models. Investigations of tumors on inbred mice (line BALB/c) after the inoculation of syngeneic myeloma cells (line Sp.2/0–Ag.8) and on inbred mice (line SHK) with spontaneous tumors have been carried out. The efficiency of application of t-LASCA with illumination by wide laser beam for tumor investigations has been proven. It also has been found that method of LASCA with illumination of tissue by strongly focused laser beam is absolutely non-productive.

Optical tweezers have been used in biophysical studies for over twenty years. Typical application areas are force measurements of subcellular structures and cell biomechanics. Optical tweezers can also be used to manipulate the orientation of objects. Moreover, using various beam shapes, optical tweezers allow measuring light scattering from single and multiple objects by keeping particles and cells in place during the measurement. At single cell level, light scattering yields important information about the object being studied, including its size, shape and refractive index. Also dependent scattering can be studied. In this paper, we review experimental work conducted in this area by our group and show new results relating to optical clearing phenomena at single microparticle level.

A simple numerical model is proposed to describe the process of OCT signal formation in a scattering medium (biological tissue) under the conditions of immersion chemical agent diffusion. Due to optical clearing of the tissue the shape of the OCT A-scan becomes time-dependent, thus providing information about the diffusion rate. The model includes the numerical solution of the diffusion equation, the relation between the concentration of clearing agent and the scattering coefficient, and, finally, the description of the OCT signal formation given the material parameters and with the probe beam geometry taken into account. The test calculations qualitatively reproduce the experimentally observed time behavior of A-scans in samples of human tooth dentine, caused by diffusion of different chemical agents. In particular, it is shown that the non-monotonic A-scans having a maximum can be explained by assuming that the backscattering coefficient giving rise to the OCT signal is, at least partially, subject to optical clearing alongside with the scattering coefficient responsible for the signal attenuation.

We are proposing a new method for enhancement of optical imaging of proximal interphalangeal (PIP) joints in humans at skin using optical clearing technique. A set of illuminating laser diodes with the wavelengths 670, 820, and 904 nm were used as a light source. The laser diodes, monochromatic digital CCD camera and specific software allowed for detection of the finger joint image in a transillumination mode. The experiments were carried out in vivo with human fingers. Dehydrated glycerol and hand cream with urea (5%) were used as optical clearing agents (OCAs). The contrast of the obtained images was analyzed to determine the effect of the OCA. It was found that glycerol application to the human skin during 60 min caused the decrease of contrast in 1.4 folds for 670 nm and the increase of contrast in 1.5 and 1.7 folds for 820 nm and 904 nm, respectively. At the same time, the hand cream application to the human skin during 60 min caused the decrease of contrast in 1.1 folds for 670 nm and the increase of contrast in 1.3 and 1.1 folds for 820 nm and 904 nm, respectively. The results have shown that glycerol and the hand cream with 5% urea allow for obtaining of more distinct image of finger joint in the NIR. Obtained data can be used for development of optical diagnostic methods of rheumatoid arthritis.

In the paper we present the results of study of rat skin and rat subcutaneous tumor under the action of dehydrating agents in terahertz (THz) range (15-30 THz). Frustrated Total Internal Reflection (FTIR) spectra were obtained with infrared Fourier spectrometer Nicolet 6700 and then they were recalculated in the transmittance spectra with Omnic software. Experiments were carried out with healthy and xenografted tumor in skin tissue in vitro. As the dehydrating agents 100% glycerol, 40%-water glucose solution, PEG-600, and propylene glycol were used. To determine the effect of the optical clearing agent (OCA), the alterations of terahertz transmittance for the samples were analyzed. The results have shown that PEG-600 and 40%-glucose water solution are the most effective dehydrating agent. The transmittance of healthy skin after PEG-600 application increased approximately by 6% and the transmittance of tumor tissue after PEG- 600 and 40%-glucose water solution application increased approximately by 8%. Obtained data can be useful for further application of terahertz radiation for tumor diagnostics.

The wide application of optical methods in the areas of diagnostics, therapy and surgery of modern medicine has stimulated the investigation of optical properties of various biological tissues. Numerous investigations related to determination of tissue optical properties are available; however, the optical properties of many tissues have not been studied in a wide wavelength range. In this work the optical properties of parietal peritoneum in the wavelength range 350-2500 nm were measured. Measurement of the diffuse reflectance, total and collimated transmittance were performed using LAMBDA 950 (Perkin Elmer, USA) spectrophotometer with an integrating sphere, and values of absorption and scattering coefficients, and the scattering anisotropy factor were calculated by inverse Monte Carlo Method.

There are lots of publications last time about important role of neuroglial interactions in normal physiology of nervous system. Some of them infer that neuroglial interactions may support survival of neuronal and glial cells. Study the mechanisms of neuroglial interactions needs convenient models which are simple nervous system. They could be easily isolated and studied while retain natural neuroglial relations. The purpose of present work was to estimate glia protective properties of giant axons in simple model – crayfish ventral nerve cord, upon photooxidative stress. To better visualize the axons shape and reveal the periaxonal glial cells, we were filling of the axons with fluorescent label by means of specially devised microinjector. It enabled us to reveal the glial cells which are in close proximity to the axons. Such glial cells was found to have increased survival in compare to more distant ones from the axons under oxidative stress. The obtained data indicate that the crayfish giant axons have glia protective properties, which molecular mechanisms have to be studied.

This paper presents an experimental study in vivo of the rate of the carboxyhemoglobin (HbCO) photodissociation in blood under the influence of the transcutaneous laser irradiation in visible spectral range from 405 to 700 nm. Despite the similarity of the HbCO and HbO2 action spectra, the designed 3-wavelengths measurement system makes it possible to obtain reliable measuring of the HbCO decrease level. The results show that there is a relatively narrow spectral range in the visible region where one could effectively (up to 50%) dissociate carboxyhemoglobin in blood through the tissue. The obtained results can be used in clinical practice on phototherapy and for effective treatment of CO poisoning.

The article describes prospective composite biocompatible titania coatings modified with hydroxyapatite nanoparticles and obtained on intraosseous implants fabricated from commercially pure titanium VT1-00. Consistency changes of morphological characteristics, crystalline structure, physical and mechanical properties and biocompatibility of experimental titanium implant coatings obtained by the combination of oxidation and surface modification with hydroxyapatite during induction heat treatment are defined.

In the present study nanoparticulate silver filler influence on adhesive system mechanical properties has been researched. In the course of laboratory experiments it has been shown that adhesive system mechanical properties are changing in a different manner as soon as silver percentage in adhesive system is increasing. It has been established that 0,5 –1% silver nanoparticle embedding into adhesive system that is enough to make the material X-Ray-sensitive holds its mechanical properties close to the optimum. Thus, the mechanical properties are enhancing in comparison with those of adhesive system without silver nanoparticles. Research findings point to the opportunity to use nanoparticulate silver as a filler while producing X-ray adhesive systems.

Restoration or replacement of lost or damaged hard tooth tissues remain a reconstructive clinical dentistry challenge. One of the most promising solutions to this problem is the development of novel concepts and methodologies of tissue engineering for the synthesis of three-dimensional graft constructs that are equivalent to original organs and tissues. This structural and functional compatibility can be reached by producing ultra-thin polymer filament scaffolds. This research aims through a series of studies to examine different methods of polymer filament material special preparation and test mechanical properties of the produced materials subjected to a tensile strain. Nanofibrous material preparation using chemically pure acetone and mixtures of ethanol/water has shown no significant changes in sample surface morphology. The high temperature impact on material morphology has resulted in the modification of fiber structure. In the course of mechanical tests it has been revealed the dependence of the material strength on the spinning solution compositions. The results achieved point to the possibility to develop nanofibrous materials with required parameters changing the methodology of spinning solution production.

The effect of heavy metal ions on the fluorescence of semiconductor ZnCdS nanoparticles in albumin solution was studied. It was found that the fluorescence intensity of ZnCdS nanoparticles depends on the albumin concentration in the solution. Interacting with ZnCdS nanoparticles, heavy metals differently affect the fluorescence intensity of the nanoparticles. Copper ions induce fluorescence quenching, cadmium ions increases the fluorescence intensity, and zinc ions do not affect the fluorescence intensity. ZnCdS nanoparticles are most sensitive to copper ions. Albumin enhances the effect of copper ions. The results on the influence of heavy metals on the fluorescence intensity of ZnCdS nanoparticles can be used to create a selective sensor for determination of copper ions in proteins using fluorescence quenching.

The temperature dependence of the fluorescent spectra of ZnCdS nanoparticles placed into a biological tissue has been investigated. It is shown that the fluorescence peak of the nanoparticles is shifted towards longer wavelengths, and fluorescence quenching is observed during heating the biological tissue until its denaturation. ZnCdS nanoparticles are suitable for measuring the temperature of biological nanoobjects under photothermolysis.

The red-shift fluorescent is often observed from the biomolecules covalently coupled with the core/shell quantum dots, while blue shift fluorescent from the electrostatic adsorption coupling structures. These fluorescent effect characteristics are analyzed on the basis of the quantum theory of condensed matter, and are demonstrated to be mainly related with the elementary excitation.

The interaction between laser and C-SQDB bio-molecule which is related with the fluorescence effect, thermal effects and eliectrical effect from the coupling structure of quantum dots bonded with bio-molecules and of have been wildly researched for the potential application in life science. .As one of the most problems, the electrical effects are analyzed by employing quantum theory in this paper and The research will be conducive to the practical application of C-S QDBS in medical science.

In the experiment the white outbred rats with transplanted liver cancer (cholangiocarcinoma line PC-1) and simulated alloxan diabetes were treated by single intravenous injection of gold nanorods. State of lipid peroxidation was evaluated by the following parameters: the malondialdehyde, lipid hydroperoxide, the average weght molecules in the serum of animals by conventional spectrophotometric methods study using a spectrofluorometer RF-5301 PC (Shimadzu, Japan). In both experimental groups of animals the significant increasing of levels of lipid peroxidation products was noted compared with control group. After intravenous administration of nanoparticles in the group of animals with alloxan diabetes the activation of a free radical oxidation was not observed, in group with transplanted liver cancer the increasing of levels of lipid hydroperoxide, malondialdehyde was established.

The oral administration of gold nanoparticles at dose 190 mg /kg animal body weight during 8 days leads to changes in the cellular composition of the mesenteric lymph nodes, the severity and reversibility of the reaction was determined by the size of gold nanoparticles. The cellular composition of the lymph nodes after the introduction of gold nanoparticle size of 1-3 nm for 8 days corresponded the control values, indicating the absence of immunotoxicity. Duration of recovery of cellular composition of the lymph nodes after administration of gold nanoparticles with size 15 nm and 50 nm does not exceed 21 days. It can be concluded that 15 nm and 50 nm nanoparticles have no immunotoxic action at oral administration.

In the present study a novel approach to caries management based on the application of nanoparticles of different nature to increase the mineral phase of demineralized dentin has been developed. Silver nanoparticles have been tested as a material for dentine matrix infiltration. Research findings clearly show that collagen fibers of demineralized dentine could be considered as a scaffold for mineral component delivery and the place where mineral growth can occur.

The microscopic mechanism of laser-biomolecule interaction is analyzed by quantum theory, including the interactions of laser with the chain of the biomolecular in the damping case and undamping case. The results show that the interaction of laser with DNA may result in the system getting into a chaotic state of biomolecules due to damping effect and changing the original molecular conformational, which will contribute to the improvement of laser medical.

The work is devoted to the spectral measurements of maple leaves. Fresh green leaves of maple were investigated in spring and summer, healthy leaves and leaves affected by fungal diseases - during the fall color change. F685/F740 parameter values for healthy and diseased maple leaves were found, as well as the change of this parameter during the growing season. The concentration of chlorophylls a and b and carotenoids in ethanol extracts of maple leaves with different pigmentation were calculated by absorption spectroscopy and the ratio of Chl a / Chl b was found.

Research is initiated to study water samples from stratified water basins in the Kandalaksha Gulf of the White Sea at different stages of their separation from the sea. The objects of research are lakes Elovoe and Nizhnee Ershovskoe located close to the Nikolai Pertsov White Sea Biological Station. Depth profiles of physico-chemical characteristics such as temperature, salinity, pH and dissolved oxygen were measured. Brightly colored green water layers were found in both lakes. Concentrations of photosynthetic organisms were estimated using absorption and fluorescence spectra of water samples from various depths.

A theoretical study has been made of the structure and IR spectrum of methyl-β-D-glucopyranoside with allowance for the influence of a hydrogen bond on them. Structural dynamic models of a free methyl-β-D-glucopyranoside molecule and its simplest complexes with the hydrogen bond, which represent variously structured dimmers, have been constructed by a density-functional method using a B3LYP functional in a 6-31G (d) basis. Energies have been minimized; structures, electrooptical parameters, force constants, and frequencies of normal modes in a harmonic approximation and their intensities in IR spectra have been calculated; hydrogen-bond energy has been evaluated. From the calculation results, the IR spectrum of a methyl-β-D-glucopyranoside sample has been interpreted and the conclusions on its structure and spectrum formation, and also on the capabilities of the employed method of density-functional theory have been drawn.

Structural-dynamic models of 2,3-di-O-nitro-methyl-β-D-glucopyranoside and its H-complexes have been obtained using density functional method. B3LYP hybrid functional and 6-31G (d) basis have been applied. Energies, structures, dipole moments, polarizabilities, frequencies of normal modes in harmonic approximation and IR intensities have been obtained. IR spectra of the complexes of 2,3-di-O-nitro-methyl-β-D-glucopyranoside and ethanol has been interpreted in 600-3700 cm^–1 region. Taking into account the results of simulation we have interpreted IR spectrum of the sample in region 600-3700 cm^-1, and determined the structure of the sample.

The peculiarities of the outside influences on the all-optical poling process and on the formed nonlinear optical structures of second-order polarizability are studied. The basic attention is given to considering the outside influences of the laser radiations with different powers and also the variations of temperature. The observed kinetics during the outside influence in the studied phosphate glass materials was investigated and it was shown the possibility of the sufficiently increase of the photo-integrated grating structures in the all-optical poling process by means of the outside thermal influence.

In present paper we investigate the transverse dynamics of frequency-modulated cw laser beam propagated in resonance conditions. At modulation periods comparable with the atomic relaxation times the time dependence of the output intensity exhibits the manifestations of resonance self-action effects. The influence of resonance self-induced lens and aperture on cw laser beam transverse profile and the boundary conditions of self-action are analyzed by numerical simulation.

The processes and the properties of the creation of the photo-refractive Bragg gratings in center-symmetrical materials by considering of the coherent interactions of the laser radiations have been analyzed. Characteristic experimental results of the scattering and the diffraction of light on photo-refractive Bragg gratings in volumetric glass materials are considered and the possible mechanisms of the observed and investigated processes are discussed.

Investigations of the nonlinear optical phenomenon of light parametrical down-frequency conversion which is appeared on micro-periodic nonlinear structures photo-integrated in volumetric optical isotropic medium on all-optical poling process are presented. The observed phenomenon is similar to the well known degenerate parametric conversion in square-nonlinear media such as the optical nonlinear crystals. Observations of the amplification of low light signals on the created micro-structured oxide glass materials and also the appearance of the photoelectric instability of the preliminarily induced optical anisotropy by illumination of medium with use the coherent monochromatic source are considered. The big growth of the intensity of small signal of the basic frequency radiation with time (a photo-induced amplification of light) has been detected in experiments with the influence upon amorphous optical material simultaneously by the weak probe radiation of the basic frequency and the strong radiation of the second harmonic. Various modes of the amplification of light signal in experimental samples were investigated in presence of the preliminary created photo-integrated nonlinear structures with different amplitudes and mechanisms of the occurrence of the parametric generation in photo-integrated structures with the existence of the non-steady regimes of signal amplification are discussed.

The entanglement of two dipole-coupled superconducting flux qubits with degenerate two-photon transitions interacting with one-mode superconducting LC circuit has been investigated. The possibility of considerable growth of atomic entanglement due atomic coherence and dipole-dipole interaction has been shown.

The entanglement of two dipole-coupled superconducting flux qubits with degenerate and nondegenerate twophoton transitions interacting with one-mode or two-mode field in lossless cavity has been investigated. The influence of dipole-dipole interaction on the entanglement between two qubits for different initial atom-field entangled states has been considered. The results show that the entanglement between two artificial atoms can be increased by means of dipole-dipole interaction and for some initial states the entanglement sudden death effect can be weakened.

An exact solution of the problem of two two-level atoms with nondegenerate two-photon transitions and intensitydependent coupling interacting with two-mode radiation field is presented. Asymptotic solution for system state vector is obtained in the approximation of large initial coherent fields. The atom-field entanglement is investigated on the basis of the reduced atomic entropy dynamics. The possibility of the system being initially in a pure disentangled state to revive into this state during the evolution process is shown. Conditions and times of disentanglement are derived.

We propose a method of generation terahertz radiation based on difference frequency mixing of colliding femtosecond pulses in the wavelength range 1550 nm. Obtaining a defined frequency difference is due to stimulated Raman soliton generation via splitting of multisoliton replica pulses in a photonic-crystal fiber. Pulse train is generated by a single laser. The results of numerical simulation of such process, based on the solution of the modified nonlinear Schrödinger equation, which includes the impact of higher-order dispersion, the optical Kerr effect and Raman amplification are presented. One of the easiest ways to generate pulses with a frequency difference is to use the fibers with variable dispersion.

Gaussian pulse ansatzs were used in description of pump and Stokes pulse nonlinear interaction in optical fiber. Modified generalized momenta method is used for derivation of the ordinary differential equations for pulse parameters allowing the gain and saturation effects.

Metamaterials, made in form of periodically arranged metal and dielectric cylindrical inclusions, have been investigated on the basis of the integral equation method, based on periodic Green's function. Metal rods are described in terms of complex permittivity [see manuscript]. Along the rods terahertz and infrared waves propagate substantially with the speed of light c and small losses weakly depending on the transverse wave number, whereas in the optical range, in particular in the shortwave part of a spectrum, they turn into the slow -waves of a dielectric waveguide.

Numerical model of fiber laser is proposed suitable for numerical investigation of fiber laser dynamics. The model is based on the equations describing propagation effects, linear coupling of oppositely running pulses and its interaction in a ring or standing-wave fiber cavity. The derivation of these equations is based on the field representation in terms of longitudinal harmonics rather than monochromatic waves. This allows to formulate easily the initial values problem for numerical simulations, to the contrast to two-points boundary values problem in the case of monochromatic wave decomposition. Numerical results are presented for the case of Raman pump by CW monochromatic laser radiation using upwind method. The results can be applied for investigation of dynamics in fiber lasers, including Raman lasers, especially with long cavities, and random feedback fiber lasers.

We are carefully analyzing the properties of the eigenwaves of 2D-structure with regularly ordered metal nanorods in lossless dielectric. Plane-wave-decomposition was used in numerical calculations. New “hyperbolic” solutions were found.

Propagation of pair of fundamental solitons in optical fiber is considered numerically. A new scenario for optical rogue wave generation is proposed. A dispersion oscillating fiber forces the interaction between fundamental solitons. Couple of solitons is merged into a single pulse. The intensity of output pulse is twice higher than the same for initial soliton. The output pulse can be delivered by constant-dispersion single mode fiber. A conversion of two-soliton breather into single pulse as a new scenario of optical rogue wave generation can be considered.

Digital holographic microscopy (DHM) combines the possibility of high resolution quantitative phase imaging with numerical focusing and in transmission mode is widely used for live cell imaging. The use of partially spatially coherent illumination in DHM provides some advantages over the conventional spatially coherent illumination, but modifies the signal properties and requires detailed investigation, especially in the part of numerical focusing. In this paper we present theoretical analysis of the effects of partially spatially coherent illumination in transmission-mode DHM on its impulse response and numerical focusing possibilities. Further, we propose a method of providing high quality impulse response (as by the spatially low-coherent illumination), preserving large maximum distance of numerical focusing.

The diffraction of a linearly polarized plane wave by a corner dielectric microstep of height equals of two incident wavelengths was studied using finite-difference time domain method and near-field scanning optical microscopy. It was shown that the corner step generates an elongated region of enhanced intensity, termed as a curved laser microjet. The curved laser microjet has a length of about DOF = 9.5λ and the smallest diameter FWHM = (1.94±0.15)λ at distance z = 5.5λ.

Circular dichroism is typical of cholesteric materials with a cholesteric pitch of the order of light wavelength, where it is connected with selective reflection of one of the circularly polarized components of light. In this work we report, for the first time, on our observations of circular dichroism on multi-domain layers of a nonabsorbing cholesteric LC material whose natural cholesteric pitch is much larger than the wavelength of incident light. It is demonstrated that the degree of manifestation of the circular dichroism depends heavily on the LC layer thickness, voltage applied to the layer, and wavelength.

A method of determining key parameters of imperfect compound zero-order quartz waveplates is proposed. Estimates obtained by this method can be used for correcting experimental data for waveplate imperfections.

The model for quantum tunneling of a diatomic homonuclear molecule is formulated as a 2D boundary-value problem (2D BVP) for the Schrodinger equation with homogeneous boundary conditions of the third type. The molecule is considered as a pair of identical particles coupled via the effective potential. For short-range barrier potentials the Galerkin reduction to BVP for a set of closed-channel second-order ordinary differential equations (ODEs) is obtained by expanding the solution in a basis of transverse variable functions. Benchmark calculations of quantum tunneling through Gaussian barriers are presented for a pair of identical nuclei coupled by Morse potential. The results are compared with the direct numerical solution of the original2D BVP obtained using the Numerov scheme. The effect of quantum transparency, i.e., the resonance behavior of the transmission coefficient versus the energy of the molecule, is shown to be a manifestation of the barrier metastable states, embedded in the continuum below the dissociation threshold, as well as quantum diffusion. The possibility of controlling the dynamics of atom-ion collisions by laser pulses is analyzed using a lD BVP two-center model with Poschl-Teller potentials.

Aimed at applications to the photonics of composite two-electron quantum systems like a helium atom in hyper­ spherical coordinates, the boundary value problem (BVP) for a system of coupled self-adjoined 3D elliptic partial differential equations of the Schrodinger type with homogeneous third-type boundary conditions is formulated in coupled-channel adiabatic approach. The Kantorovich reduction of the problem to BVPs for ordinary second­-order differential equations (ODEs) with respect to functions of a single hyper-radial variable is implemented by expanding the solution over a set of surface (angular) functions that depend on the hyper-radial variable as a parameter. Benchmark calculations are presented by the example of the ground and first excited states of a Helium atom. The convergence of the results with respect to the number of the surface functions and their components is studied. The comparison with the known results is presented.