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Some of the achievements of modern optical metrology are offered for the reader at this chapter. Optical testing methods have always attracted by their important advantages: distance, non-destructive impact on the test object and, of course, high accuracy. So, using of polarization optics approach, the authors were able to implement the methods for controlling the surface roughness for the moving surface with the measurement accuracy of 10 angstroms. It has become possible to make a breakthrough in the basic methods of measurements from the nano to the femto or pico units of the measured quantity value over the past decades. Control of nano (micro) particle motion by an optical field and their use for testing complex optical fields; ultra-precise determination of the optical parameters of both solid and liquid and gas-like substances by optical methods; by interference methods and many other, are proposed for consideration here. Some biomedical applications are also offered for reader’s familiarization. Particularly, the results of 3D Stokes-polarimetric mapping of microscopic biological images with digital holographic reproduction of layer-by-layer ellipticity polarization maps in differential diagnosis of benign and malignant tumors with different degrees of differentiation are presented. The authors have shown that using of polarization-holographic measurements in biomedical applications makes it possible to obtain a reliable diagnostic of pathological states both of biological fluids and solid-state objects.

We propose a new approach of using carbon nanoparticles for correlation optical diagnostics of а complex scalar optical field created by scattering and diffraction of radiation off a rough surface. This surface is simulated and we generate a diffraction pattern of the amplitude and phase distribution in the far field. Carbon nanoparticles of a certain size and concentration are obtained by the bottom-up methods of hydrothermal synthesis of citric acid and urea followed by centrifugation. The optical properties of carbon nanoparticles, such as luminescence and absorption in the visible spectrum that essentially differs for different wavelengths, as well as particle size of about dozen nanometers, are the determining criteria for using these particles as probes for the optical speckle field. Luminescence made it possible to register the coordinate position of carbon nanoparticles in real time. The algorithm for reconstruction of the scalar optical field intensity distribution through the analysis of the nanoparticle positions is here displayed. The skeleton of the optical speckle field is analyzed by Hilbert transform to restore the phase. Special attention is paid to the restoration of the speckle field’s phase singularities.

The idea of the proposed paper is a demonstration of the evanescent wave effect on nano-objects of inorganic and organic (in particular, formed blood elements) origin localized in a biological medium, in the direction perpendicular to the direction of the Pointing vector action. On the one hand, this opens up (illustrates) new possibilities in the optical control of the direction of motion and speed of the studied nanoobjects in a layer of biological fluid. On the other hand, the very choice of objects of this type suggests the possible prospects for their use in biology, medicine, pharmacology, and precision chemistry. So, in particular, gold nanoparticles, being non-toxic to the body, are able to penetrate through the cell biomembranes, accumulate in them, thereby contributing to the diagnosis of the cell state with subsequent optical exposure to them, up to destruction in case of cancer pathologies. The role of red blood cells (RBS) in the body is generally unique and controlling their motion contributes to the complex saturation of tissues with oxygen. The choice of just the evanescent wave is explained by the need for near-surface manipulation of optical energy flows, which is especially important in the situation of studying biological complexes and structures. Exclusive manifestation of the evanescent wave action became possible under specially selected experimental condition of evanescent wave exitation. A total internal reflection was realized at the interface between the prism and a biological medium by a linearly polarized wave with the azimuth of polarization of ±45°. The result of such an excitation mechanism was a complex distribution of the optical flow density, which is accompanied by a change in the energy density both in the longitudinal direction coinciding with the direction of the wave vector and in the transverse direction perpendicular to the wave vector. The paper summarizes the latest theoretically and experimentally obtained results illustrating the rectilinear and rotational motion of investigated objects in a biological environment.

The paper briefly presents some essential concepts and features of light fields with strong spatial inhomogeneity of amplitude, phase, polarization, and other parameters. It contains a characterization of optical vortices, speckle fields, polarization singularities. A special attention is paid to the field dynamical characteristics (energy, momentum, angular momentum, and their derivatives), which are considered not only as mechanical attributes of the field but also as its meaningful and application-oriented descriptive parameters. Peculiar features of the light dynamical characteristics in inhomogeneous and dispersive media are discussed. The dynamical properties of paraxial beams and evanescent waves (including surface plasmon–polaritons) are analyzed in more detail; in particular, a general treatment of the extraordinary spin and momentum, orthogonal to the main propagation direction, is outlined. Applications of structured light fields for optical manipulation, metrology, probing, and data processing are described.

An investigation of the influence of an evanescent wave on the dynamics of motion of erythrocytes in blood plasma is presented. Computer simulation of erythrocytes moving in an evanescent field and experimental demonstration of the forecasted motion substantiate the possibility for control of position of red blood cells in a solution. The range of velocities of transversal motion of erythrocytes due to the action of the optical force of the generated evanescent field is determined as a function of the angle of illumination of a cell by a linearly polarized wave with the azimuth of polarization 45 deg.

The interaction of two mutually orthogonal linearly polarized waves in the incidence plane, where the modulation of polarization and the modulation of the energy volume density occur simultaneously in the observation plane is considered. The spatial modulation of polarization in the observation plane forms the spatial modulation of the energy volume density, which changes the velocity of the particle’s motion according to the coherence characteristics of superposing fields and the resulting optical force that causes the motion of tested particles of micrometer range size. Peculiarities of particle’s motion in a spatial periodically modulated polarized field are determined by coherent properties of interacting optical fields.

We propose an optical correlation algorithm for reconstructing the phase skeleton of complex optical fields from the measured two-dimensional intensity distribution. The essence of the algorithm consists in location of the saddle points of the intensity distribution and connecting such points into nets by the lines of intensity gradient that are closely associated with the equi-phase lines of the field. This algorithm provides a new partial solution to the inverse problem in optics commonly referred to as the phase problem.

Water suspension of light-absorbing nano-sized particles is an example of a medium in which non-linear effects are present at moderate light intensities favorable for optical treatment of organic and biological objects. We study experimentally the phenomena emerging in a thin layer of such a medium under the action of inhomogeneous light field formed due to the Pearcey diffraction pattern near a microlens focus. In this high-gradient field, the light energy absorbed by the particles induces inhomogeneous distribution of the medium refraction index, which results in observable self-diffraction of the incident light, here being strongly sensitive to the medium position with respect to the focus.

The media of layered crystals as a possible element of memory in the storage systems were analyzed, the manipulation mechanisms of which are carried out with polarization of incident radiation. The phenomenon of polarization optical bistability in the medium of layered crystals was obtained, in which the transmission band is managed with only the change of polarization of incident radiation. On the basis of the mechanism of polarization control of nanoparticles motion in the tasks of polarization diagnostics of optical fields, the estimation of the coherent features of mutually orthogonal linearly polarized optical fields was performed that also enables to analyze the terms of storage of information about the structure of an optical field.

Study of the internal energy flows is a rapidly developing branch of physical optics (see, e.g., Refs. [1–8]). The internal flows (optical currents) not only constitute an “energy skeleton” of a light field, which reflects important physical characteristics of its spatial structure. They have proven to be valuable instruments for investigation of fundamental dynamical and geometrical aspects of the light fields’ evolution and transformations [1–5], provide a natural language for explaining the special features of singular fields [1, 2, 4-6], fields with angular momentum [3,6-8] and for interpreting the effects of spin-orbit interaction of light [5]. As physically meaningful and universal parameters of light fields, they permit to disclose physical mechanisms of the beam transformation upon free and restricted propagation and offer attractive possibilities for characterization of arbitrary light fields [5].

Non-spherical dielectric microparticles were suspended in the water-filled cell and exposed to the coherent Gaussian light beam with switchable state of polarization. When the beam polarization is linear, the particles were trapped at certain off-axial position within the beam cross section. After switching to the right (left) circular polarization, the particles performed spinning motion in agreement with the angular momentum imparted by the field, but also they were involved in the orbital rotation around the beam axis, which in previous works [Y. Zhao et al, Phys. Rev. Lett. 99, 073901 (2007)] was treated as an evidence for the spin-to orbital angular momentum conversion. Since in our situation the moderate focusing of the beam excluded possibility of such a conversion, we treat the observed particle behaviour as a demonstration of the macroscopic “spin energy flow” predicted by the theory of inhomogeneously polarized paraxial beams [A. Bekshaev et al, J. Opt. 13, 053001 (2011)].

It is known that internal energy flow in a light beam can be divided into the orbital flow, associated with the macroscopic energy redistribution within the beam, and the spin flow originating from instantaneous rotation of the field vectors inherent in circular or elliptic polarization. In contrast to the orbital one, experimental observation of the spin flow constituent seemed problematic because (i) it does not manifest itself in the visible transformation of the beam profile and (ii) it converts into the orbital flow upon tight focusing of the beam, usually employed for the energy flow detection by the mechanical action on probe particles. We propose a two-beam interference technique that permits to obtain appreciable level of the spin flow in moderately focused beams and to detect the orbital motion of probe particles within a field where the transverse energy circulation is associated exclusively with the spin flow. This result can be treated as the first demonstration of mechanical action of the spin flow of a light field.

The paper presents a new method for determining the degree of coherence of superposing plane linearly polarized waves converging at the angle of 90°. The spatial modulation of polarization, which causes the spatial modulation of the averaged values of the Poynting vector, presets the modulation of the volume energy density. Such an inhomogeneous optical field can affect nano-sized particles randomly caught in this field. The paper shows that the maximum velocity of “trapping” the particles into the regions of maximum averaged values of the Poynting vector determines the degree of coherence of interacting waves.

The paper proposes for consideration an additional possibility to evaluate the degree of coherence of superposing mutually orthogonal linearly-polarized in the incidence plane waves. When analyzing the behavior of various-type particles (Mie and Rayleigh) in the inhomogeneously polarized optical field and in the inhomogeneous field of the averaged values of the Poynting vector, we obtain an additional tool for defining the degree of coherence of interacting fields. The spatial modulation of polarization in the observation plane shapes the spatial modulation of the energy density volume, which changes the velocity of the particle motion according to the coherence characteristics of the superposing fields and to the resulting optical force that causes the motion and trapping of the tested particles.

The influence of phase relations and the degree of mutual coherence of superimposing waves in the arrangements of twowave superposition on the characteristics of the microparticle's motion has been analyzed. The prospects of studying temporal coherence using the proposed approach are made. For the first time, we have shown experimentally the possibility of diagnostics the optical currents in liquids caused by polarization characteristics of an optical field alone, using test metallic particles of nanoscale.

We present the results of computer simulation of the spatial distribution of the Poynting vector and illustrate motion of microparticles and nanoparticles in spatially inhomogeneously polarized fields. The influence of phase relations and the degree of mutual coherence of superimposing waves on the characteristics of the microparticle’s motion has been analyzed. For the first time, we have shown experimentally the possibility of diagnostics of optical currents in liquids caused by polarization characteristics of an optical field alone, using test metallic particles of nanoscale.

The mathematical estimation of the degree of correlation of optical fields in the near field has been analyzed. The need for taking into account the modulation of polarization and the modulation of intensity in measuring the visibility of the interference pattern has been demonstrated.

The impact of temperature, incident light polarization and a weak external magnetic field upon the conditions of optical bistability (OB) realization in the exciton absorption region of layer semiconductors has been investigated. With the 2Hpolytype PbI2 used as an example, the possibility of obtaining the OB realization region by changing the external factors has been shown. It has been also demonstrated that the change of these parameters can control the position and values of the absorption hysteresis loop of corresponding layer crystal excitation exciton zones.

The statement is substantiated that the experimental estimation of the degree of correlation of statistical vector optical fields must include not only the measurement of the visibility of the interference pattern, but also the deepness of the polarization modulation (degree of polarization) in the resulting spatial distribution of a field.

The statement is substantiated that the experimental estimation of the degree of intrinsic coherence of statistical vector optical fields must include not only the measurement of the visibility of the interference pattern but also the degree of polarization in the resulting spatial distribution of a field.

A new mechanism of memory cell formation on structural biological units of the α-helical protein molecules is suggested in this work. The role of Frenkel excitons and "Davydov splitting" in the resonance mechanism of external excitation energy transmission along peptide groups is defined. Using the Green function method was obtained the theoretical bases of the protein cell absorptive power formation under external laser irradiation. The polarization peculiarities of α - protein exciton excitations at such levels of pumping, which allow to obtain a complex outlet signal reaction, were studied. Protein molecules can serve as perspective material for observing the effect of optical bistability. The results of the performed investigations permit to develop one of the lines of the molecular engineering technologies - the creation of molecular memory devices by controlling the laser radiation of the outlet protein molecule.

The impact of a weak external magnetic field upon the conditions of optical bistability (OB) realization in the exciton absorption region of layer semiconductors has been investigated. With the 2H-polytype PbI 2 used as an example, the possibility of obtaining the OB realization region by changing the external magnetic field intensity has been shown. This effect can be used as a basic guideline in measuring the level of laser radiation signals, and can provide means for metrological maintenance of systems working in different active regime.

The theoretical investigation of the role of bending waves in the process of creating conditions for observing optical bistability in layer semiconductors was performed by the Green function method. Using the 2H-polytype of Pb12 as an example. we showed that effective exciton scattering by oscillations of this type leads to a short wave shift of the frequency tegion. the decrease of its sizes. the widening of the temperature interval optical bistability realization of its observing, the shill the hysteresis loop into bigger intensities and the decrease of its height and width.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The influence of the exciton and phonon spectra of layer semiconductors on the conditions of optical bistability (OB) realization in the exciton absorption region is investigated by means of the Green function method. Using the 2H-polytype PbI2 as an example, it has been found that an effective exciton scattering by an oscillation of the bending wave (BW) type leads to the short wave shift of the OB realization region, the decrease of its size, the widening of the OB observing temperature region and to the shift of the hysteresis loop in the direction of greater intensities, the decrease of its height and width. The possibility of observing the polarizable OB, connected with the direction of spreading and the insident light polarization dependence ofthe layer crystal exciton spectra is substantiated in this paper.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The influence of an external magnetic field on optical features of semiconductor exciton spectra is researched in this work. It is shown that the magnetic field brings about the shift of the exciton level in the high-energy spectrum area. This causes the arising of a unique effect-- brightening-- of the crystal on the fixed external excitement frequency with the growth of the magnetic intensity value. The combination of electronic and magnetic characteristics of a crystal in an exciton frequency region opens new possibilities of giving control over the bistable behavior of the crystal. It is shown that the magnetic- optical response of a semiconductor on laser excitation generates bistable loops, both on the intensities of falling light (tau) (T) and in the size of the magnetic field-- (tau) (Hyields).

This paper proposes for consideration an additional mechanism for influencing the exciton absorption spectra and observing temperature redistribution peculiarities of the crystal absorptive power. They are caused by nonlinear phonon-exciton interactions, which are due to anharmonic effects in the exciton-phonon system. The arising of the borderline frequency, which possesses the smallest region of optical bistability realization, is caused by a break in the direction of the absorption curve. At low temperatures the basic role is played by the exciton-exciton interaction, and at high temperatures nonlinear exciton-exciton-phonon processes play the most important role the value of the borderline frequency is defined by the size and sign of the nonlinear exciton-exciton-phonon function as well as by the crystal temperature and the exciton density, which is created by the external powerful laser wave.

In this paper one of the methods of polarimeter investigation of exciton spectra is proposed. The analysis is based on the peculiarities of semiconductor layer crystals, the dipole moment of the exciton transition and one of the main properties of the laser wave, its polarization. As a result, libation oscillations of the exciton dipole become quite actual in anisotropic semiconductors. This leads to the change of the mechanism of light absorption on the exciton frequencies and to the actualization of the indirect vertical phototransition with the change of the polarization angle. These processes result in the depolarization of the absorption spectrum, its structurization, and redistribution of the power along the frequency scale. Finally, the dying away of purely exciton absorption and the increase of oscillatory components take place.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The nonlinear light transmission of semiconductors, in which the indirect exciton phototransition is realized, is studied. It is shown that the presence of two channels of dissipation of light wave energy of the indirect phototransition (the excitation of libration phonons) and exciton relaxation (the excitation of lattice phonons) -- leads to arising of optical multistable states in crystals. Investigations of polarization peculiarities of the dynamics of nonlinear processes with changing intensity of the input signal have been carried out.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The results of theoretical investigations of the role of the dipole moment of excitons during the formation of optical spectra of exciton absorption are presented in this work. Using the model of the indirect phototransition, we calculated the frequency distribution of the coefficient of exciton absorption for different temperatures. It is shown that libration oscillations lead to temperature dependences of the integral absorption; stipulate the anomalous temperature changes of the height of the exciton absorption peak, and make the exciton absorption band structural.

We discuss interconnections between the depth of spatial inhomogeneity of energy distribution of the optical fields and the velocity of motion of test particles for the cases of different light scattering mechanisms during interaction with light. We suggest an additional tool for determining the degree of coherence of superposing waves that propagate along mutually orthogonal directions and have orthogonal polarisations, being linearly polarised in the incidence plane. The use of velocity of the test particles while estimating the degree of coherence of optical fields is suggested for the first time.