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In yttrium aluminum garnet (YAG) crystals containing terbium and cerium impurities, along with the main EPR signals of Tb3+ and Се3+ ions located in the dodecahedral sites of the YAG lattice in a regular environment, EPR lines with a lower (several percent) intensity were observed. They also belong to the paramagnetic centers of terbium and cerium, but are characterized by slightly altered parameters—the initial level splitting for non-Kramers Tb3+ ions and g-factors for Се3+ ions. It is shown that the nature of such centers and their number can be explained by the presence of YAl antisite defects, i.e. yttrium ions in the octahedral aluminum positions, in the environment of Tb3+ and Се3+.

The methods of high-frequency electron paramagnetic resonance (EPR), electron spin echo (ESE) and optically detected magnetic resonance (ODMR) are used to study the unique properties of nitrogen-vacancy (NV) defects in diamond in strong magnetic fields. It is shown that in strong magnetic fields (∼3–5 T) there occurs an effective optically induced alignment of populations of spin levels resulting in filling the level MS = 0 and emptying of the levels MS = ±1, that makes it possible to record ODMR using the change in the intensity of photoluminescence which reaches 10% at resonance. It is demonstrated that the efficiency of the alignment has the same order as in zero and low magnetic fields. The samples were preliminary studied by the ODMR method in zero magnetic fields that allowed accurate determination of the main parameters of the fine structure and hyperfine interactions with nitrogen nuclei, as well as dipole-dipole interactions between the NV center and deep nitrogen donors in the form of a nitrogen atom replacing carbon, N0. Hyperfine interactions with the nearest carbon atoms (isotope 13C) were observed in the high-frequency ODMR spectra, that opens up opportunities for measuring the processes of dynamic polarization of carbon nuclei in strong magnetic fields using optical methods. It is assumed that narrow ODMR lines in strong magnetic fields can be used to measure these fields with submicron spatial resolution. A new method for recording ODMR of NV centers with microwave frequency modulation has been developed, which simplifies the technique of measuring high magnetic fields. A significant increase in the intensity of the ODMR signal was demonstrated when a strong magnetic field was oriented along the symmetry axis of the NV center.

The advantage of the high-frequency spectroscopy of electron paramagnetic resonance (EPR) for the identification of nitrogen donors and a deep compensating vanadium impurity in various crystallographic positions of the silicon-carbide crystal is shown. Measurements are performed using a new generation EPR spectrometer operating in the continuous wave and pulsed modes at frequencies of 94 and 130 GHz in a wide range of magnetic fields (–7–7 T) and temperatures (1.5–300 K). A magneto-optical closed-cycle cryogenic system (Spectormag PT), highly stable generators (94 and 130 GHz), and a cavity-free system for supplying microwave power to the sample are used.

Electron paramagnetic resonance (EPR) spectra of Ce3+, Yb3+, Cr3+, and Gd3+ impurity ions in yttrium aluminum garnet Y3Al5O12 (YAG) ceramics were detected and identified at frequency of 94 GHz. The advantage of measuring the EPR spectra in the high-frequency range compared to the standard EPR technique is shown, which makes it possible to separate the EPR spectra characterized by different anisotropic g-factors and also to isolate the EPR signals due to the splitting of the fine structure for centers with high-spin states. In ceramics with a high content of magnetic Gd3+ ions, EPR and electron spin echo (ESE) spectra of multi-ionic gadolinium complexes were observed, and EPR spectra of complexes with the maximum number of exchange-coupled gadolinium ions are seen at low temperatures. The temperature dependences of the EPR spectra indicates ferromagnetic ordering of exchange-coupled complexes of gadolinium.

Samples of a superconducting indium nanocomposite based on a thin-film porous dielectric matrix prepared by the Langmuir–Blodgett method are obtained for the first time, and their low-temperature electrophysical and magnetic properties are studied. Films with thickness b ≤ 5 μm were made from silicon dioxide spheres with diameter D = 200 and 250 nm; indium was introduced into the pores of the films from the melt at a pressure of P ≤ 5 kbar. Thus, a three-dimensional weakly ordered structure of indium nanogranules was created in the pores, forming a continuous current-conducting grid. Measurements of the temperature and magnetic field dependences of the resistance and magnetic moment of the samples showed an increase in the critical parameters of the superconductivity state of nanostructured indium (critical temperature Tc ≤ 3.62 K and critical magnetic field Hc at T = 0 K Hc(0) ≤ 1700 Oe) with respect to the massive material (Tc = 3.41 K, Hc(0) = 280 Oe). In the dependence of the resistance on temperature and the magnetic field, a step transition to the superconductivity state associated with the nanocomposite structure was observed. A pronounced hysteresis M(H) is observed in the dependence of the magnetic moment M of the nanocomposite on the magnetic field at T < Tc, caused by the multiply connected structure of the current-conducting indium grid. The results obtained are interpreted taking into account the dimensional dependence of the superconducting characteristics of the nanocomposite.

Optical properties of novel metal–dielectric nanocomposite materials based on opal matrices have been investigated. The position of optical resonances of nanocomposites, obtained by embedding of silver into the opal matrix by the electrothermodiffusion method, is explained by the Bragg diffraction, and an asymmetric form of resonance curves is attributed to the Fano resonance. An anomalous transmission and absorption of light by hybrid plasmon-photonic layered heterostructures, which is apparently associated with excitation of surface plasmon-polaritons, propagating along “metal–dielectric” interfaces, was revealed.

The structure and optical diffraction properties of monolayers of monodisperse spheres crystallized on transparent dielectric substrates are studied. Two types of diffraction phenomena are considered: surface light diffraction on the lattice of spheres and waveguide resonances in the monolayer plane. For experimental study of these phenomena, optical retroreflection and transmission spectra are measured as functions of the light incidence angle and azimuthal orientation of the incidence plane. The monolayer structures determined by scanning electron microscopy and light diffraction methods are in quantitative agreement. It is concluded that one-dimensional Fraunhofer diffraction is applicable to describe surface diffraction in the hexagonal lattice of spheres. In the case of oblique light incidence, anisotropy of diffraction and transmission spectra depending on the light incidence plane orientation with respect to the sphere lattice and linear polarization of incident light is detected. Waveguide resonances of the planar two-dimensional photonic crystal are approximated within the light diffraction model in the “empty” hexagonal lattice. The best approximation of the waveguide resonance dispersion is achieved using the effective refractive index, depending on the wavelength. Surface diffraction suppression by waveguide resonances of the photonic crystal is demonstrated. Surface diffraction orders are identified as diffraction at singular points of the Brillouin zone of the planar twodimensional photonic crystal.

An optical quantum thermometer with submicrometer resolution is proposed. Its operation is based on the physical phenomenon of the optical response in a system of spin centers in silicon carbide under conditions of anticrossing of spin sublevels of the excited quadruplet state (S = 3/2) with temperature-dependent fine-structure splitting.

In this work we have performed an analysis of electrostriction mechanism of optical to acoustical energy conversion on the interface of two materials with low optical absorption. We compared this method of conversion with widely used thermal conversion based on thin metal film. It was shown, that the contribution of electrostriction mechanism is significantly lower in case of homogeneous medium. We demonstrated the possibility to amplify the generated acoustic signal by excitation of the guided modes, which energy is localized in a thin (of about 200-400 nm thickness) dielectric layer. Due to high electromagnetic field energy concentration in the structure, local values of intensity increase by more than two order of magnitude in comparison to intensity of incident light, that also allows to increase the amplitude of the pressure correspondingly. Thus, in the project we propose the novel layered dielectric structures, in which electrostriction effect occurs due to excitation of the guided modes.

Exchange-coupled complexes consisting of Mn ions and holes have been revealed by optically detected magnetic resonance in the narrowest quantum wells of asymmetrical multiple-quantum-well structures (CdMn)Te/(CdMg)Te. Calculations have been performed to estimate the parameters of the complexes (exchange interactions and hole g-factors) and simulate the spectra. The formation of such complexes implies the directional electron tunneling from narrow to larger wells, i.e., an electron cascade, which results in the creation of the excess hole concentration in the narrowest and intermediate-width quantum wells.

Long-lasting afterglow of ZnO single crystals grown by hydrothermal method has been studied using high-frequency (94 GHz) optically detected magnetic resonance (ODMR) at helium temperatures. Giant (up to 30%) afterglow intensity-detected electron paramagnetic resonance signals of shallow donors and deep acceptors, which are lithium atoms substituting for zinc in the ZnO lattice, unambiguously indicate a spin-dependent character of the donor-acceptor recombination. The observed variations in the shape of the afterglow-detected ODMR spectra of lithium acceptors with time passed after irradiation are associated with the difference in the recombination rates of shallow donors with axial and non-axial LiZn centers and with a change in the recombination character with time.

Here \(H=(H_1,H_2,H_3)\) and \(E=( E_1,E_2,E_3)\) are vectors of electric and magnetic strengths, \(\varepsilon >0\), \(\mu >0\) and \(\sigma \) are the permittivity, permeability and conductivity coefficients, respectively, which define electro-dynamical parameters of a medium.

Angle-resolved polarized transmission spectra of thin-film opals are studied experimentally and theoretically as a function of the azimuthal rotation of the plane of incidence at different angles of light incidence. In such 3-dimensional lattices, the refraction acquires the form of diffraction orders, each with a distinct spectrum, that propagate simultaneously along different directions. The corresponding continuous and patchy stop-bands in the photonic energy band structure of the opal photonic crystal are determined numerically. For diffraction at high Miller index planes, the diffraction pattern is often distorted due to multiple-wave diffraction. The finite stacking of hexagonally close-packed layers leads to an intrinsic 3-fold rotation symmetry of these spectra, which is particularly pronounced in transmission for frequencies that correspond to wave vectors within the 1st Brillouin zone. Despite the cubic symmetry of the opal lattice, cross-polarization coupling effects occur in the volume of the opal crystal. These effects are associated with the fact that, the opal eigenmodes are Bloch waves whose electromagnetic field distributions and dispersion relations are markedly different from plane waves.

Based on colloidal crystals of various dimensionality, hybrid metal-dielectric plasmonic-photonic heterocrystals have been prepared. It has been shown that the spectra of optical transmission of heterocrystals are mostly controlled by the sum of contributions of composing plasmonic and photonic crystals. At the same time, there are a number of phenomena caused by the mutual effect of heterostructure components, which lead to a deviation of observed optical properties from the linear superposition of responses of these crystals. In particular, it has been found that the anomalous transmission controlled by the plasmonic crystal decreases with increasing the dimensionality of the photonic crystal attached to it. At the same time, light reflection on a metallized surface changes light diffraction in photonic crystals and leads to Fabry-Perot oscillation amplification. It has been assumed that an intermediate layer is formed, in which Bloch modes of the photonic crystal and surface plasmon-polaritons of the plasmonic crystal are hybridized.

To perform optical detection of high-frequency magnetic resonance (ODMR) and cyclotron resonance (ODCR) with a spatial resolution, we have proposed a noncavity scheme of an ODMR-ODCR spectrometer using a quasi-optical microwave channel. The efficiency of this scheme for obtaining information on the spin properties of ZnO quantum dots and CdMnTe quantum wells and on the effective masses of carriers in crystalline silicon films with a spatial resolution within a focused laser beam is illustrated.

The excitation of acoustic oscillations in absorbing liquids exposed to pulsed Bessel light beams has been considered theoretically. Spatial profiles of refractive index diffraction patterns and the kinetics of their excitation and relaxation have been studied based on a numerical solution of continuous medium motion equations in a Lagrangian form and a heat-transfer equation and using the Lorentz–Lorenz formula. The conditions for optimal excitation of spatially localized acoustic pulses have been determined.

EPR studies presented here reveal the presence of three different types of shallow donor (SD) impurities in AlN single crystals: one impurity is located at the N site (preferentially oxygen, labeled D1) and two impurities are located at the Al site (preferentially carbon and silicon, labeled D2 and D3) of the AlN lattice. We show that D1 and D2 centers exhibit a DX-like relaxation. The light-induced EPR signals of the D1 and D2 centers are characterized by slightly anisotropic g factors typical for SD in AlN but strongly different anisotropic EPR linewidths ΔB. The D3 center shows the SD behavior at the room temperature and can be observed without light excitation at the temperatures above 200 K. Combining EPR, optical absorption and thermoluminescence induced by the X-ray irradiation we establish the structure of deep level color centers in AlN - a neutral nitrogen vacancy VN. The an optical absorption band of the center is in the visible region with a maximum at ∼450 nm and the energy level at ∼0.75 eV relative to the bottom of AlN conduction band (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Broadband, omnidirectional, and polarization-independent diversion has been achieved of more than 90% of the light fl ow intensity off its incidence direction using hybrid metal‐dielectric plasmonic-photonic heterocrystals. These architectures were prepared by depositing metal fi lm on the interface between two photonic crystals of different parameters. The magnitude of light losses was extracted from angle-resolved measurements of transmission and refl ectance spectra. Comparing these data for different stages of constructing the complex architecture, the diffraction in colloidal crystals, the excitation and radiative decay of short-living surface plasmon polaritons in a corrugated metal fi lm and the eigenmode mismatch at the interface between two different photonic crystals were identifi ed as corroborating physical mechanisms behind the light diversion.

A numerical model making it possible to consider, with exhaustive completeness, processes that occur in the absorbing spatially inhomogeneous liquid medium on exposure to pulsed laser radiation has been presented. Numerical experiments have shown the efficiency of the presented procedure of calculation in a wide range of pulse durations (from micro- to femtosecond ones) and for typical energy parameters of laser systems.

Hybrid photonic crystals consisting of a thin-film opal and a thin profiled gold film situated on the surface or inside the opal have been prepared. The optical transmittance spectra of hybrid crystals have been studied. It has been found that the spectra exhibit minima due to diffraction resonances in the photonic crystal and bands of enhanced transmission due to transfer of radiation through the metal film surface by plasmon polaritons. It has been shown that the transmittance spectra of hybrid crystals with a metal film on the surface are subjected to a stronger modification than the hybrids having a metal film inside the crystal.

ZnO provides conditions for the formation of a variety of micro/nanostructures which act as laser resonators sustaining guided modes, whispering gallery modes, random lasing and a combination of them. The scanning cathodoluminescence spectra and images of a ZnO nanorod with two mirrors at the end faces are studied at 10 K. Emission peaks of bound excitons and edge luminescence are observed in the ultraviolet spectral region. The spatial distribution pattern of emission intensity corresponding to localized photon modes of the nanorod is recorded at different wavelengths. A new method of visualization of localized optical modes in micro- and nano-sized laser cavities is suggested. The lasing peaks display successive onset and saturation with increasing excitation power density, and fit well the expected resonance spectrum of guided modes in hexagonal ZnO nanorods (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This paper reports on the measurements (in linearly polarized light) of the transmission and reflection spectra of colloidal photonic crystals with three-dimensional and one-two-dimensional photonic band structure, i.e., opal films and Langmuir-Blodgett crystals with a refractive index contrast of ∼1.5: 1.0. It has been shown that the polarization anisotropy is enhanced considerably in the diffraction resonance range both in transmitted and reflected light, and that the anisotropy in the resonance range can be as high as 99%. The interaction of photonic crystal eigenmodes has been found to affect the polarization anisotropy. The assumption has been made that the coincidence of the maxima in polarization anisotropy of the resonant and nonresonant light reflection in colloidal crystals originates from the disorder in their lattices. The generality of the results obtained is confirmed by the fact that the polarization anisotropy manifests itself in the same way in colloidal crystals with different lattice symmetries.

Photonic heterocrystals are prepared by sandwiching films of self-assembled opal and force-assembled Langmuir–Blodgett colloidal crystals. Anomalously strong light scattering in conjunction with low reflectivity is observed with increasing angle of incidence in the spectral range of photonic bandgaps. The occurrence of light scattering at the interface has been assigned to the optical mode mismatch between the two types of photonic crystals. Photonic bandgap-related mechanisms of trapping the decaying photonic crystal modes at the interface are suggested.

The transmission spectra of thin-film colloidal photonic crystals with three-dimensional and one-dimensional-two-dimensional photonic energy band structures, i.e., opals and Langmuir-Blodgett crystals with a refractive index contrast of ∼1.5: 1.0, have been measured in linearly polarized light. It has been demonstrated that the polarization anisotropy in the light transmitted through the crystal is uniquely related to the diffraction resonance and that the degree of polarization can exceed 90%. A higher degree of polarization is provided by lattices that are characterized by a smaller attenuation of light polarized in the plane of incidence. It has been revealed that the diffraction resonances from the crystal planes for which the dispersions are in anticrossing with the dispersion of the growth planes acquire the same anisotropy. The general character of the results obtained has been confirmed by the fact that the polarization anisotropy identically manifests itself in colloidal crystals that have different symmetries and lattice orderings.

Long-lasting (several hours) afterglow at helium temperatures was observed in ZnO nanocrystals, 36 nm in size, after switching off the UV excitation. A quenching of the afterglow intensity in the magnetic field was found, which appears because of the preferential orientation of the recombining spins along the field and the spin-dependence of the recombination. ODMR was detected as resonance increase in the afterglow intensity at saturation of the EPR transitions of defects, which take part in the recombination. Shallow donors and different types of acceptors responsible for the afterglow in Al doped ZnO nanocrystals were identified. ODMR of donors and Li acceptors was recorded via the afterglow of bulk ZnO:Li, which could last for about an hour. In the photoluminescence-detected ODMR of bulk ZnO:Li crystals exchange-coupled donor–acceptor pairs were observed in addition to the Li acceptor and donor signals. Exchange-coupled pairs dominated the ODMR spectra recorded on the photoluminescence of ZnO nanocrystals.

The centers involved in the spin-dependent recombination in KCl: AgCl insulator-semiconductor wide-band-gap crystal structures, bulk ZnO crystals, and quantum dots based on ZnO nanocrystals have been identified by detecting electron paramagnetic resonance from tunneling afterglow. Long tunneling after-glow has been excited by short-term UV irradiation of the sample at liquid-helium temperatures. The observed magnetic quenching of the afterglow at low temperatures results from the Boltzmann polarization of spins of recombination centers. The revealed giant increase in the afterglow intensity is induced by the reorientation of spins of these centers at electron paramagnetic resonance. A new technique for recording the spectra at a high frequency of 94 GHz has been developed and used with the aim of increasing the sensitivity and spectral resolution. This technique has made it possible to separate electron and hole centers in the KCl: AgCl structures and to demonstrate that ZnO: Al quantum dots contain two types of deep acceptors.

The transformation of singular light beams is analyzed theoretically for multiwave interactions on amplitude and phase dynamic holograms in media with a resonant nonlinearity. The possibility of multiplying topological charge using different diffraction orders is demonstrated and optimal conditions for parametric energy exchange are determined which ensure retention of the structure of the wave front of optical vortices.

The scanning cathodoluminescence spectra and images of a ZnO nanorod with two mirrors at the end faces are studied at 10 K. Emission peaks of bound excitons and edge luminescence are observed in the ultraviolet spectral region. The spatial distribution pattern of emission intensity corresponding to localized photon modes of the nanorod is recorded at different wavelengths. A new method of visualization of localized optical modes in micro- and nano-sized laser cavities is suggested.

This work is devoted to the quantitative evaluation of the lattice ordering of opal films. Assembling colloidal crystals in a moving meniscus under random noise agitation produced opal films with generically the same lattice but different disorders. The lattice ordering is quantified by the magnitudes of harmonics in the Fourier transforms of (i) the scanning electron microscopy images to address the in-plane lattice ordering and (ii) rotation diagrams of the optical transmission to address the regularity of crystal planes. In prepared opals, the strong deviation of the lattice from the face-centered cubic symmetry is demonstrated. We find uneven lattice responses to changing the growth conditions, e.g., the 30% improvement of the hexagonal lattice ordering in the (111) growth plane accompanied by a ten-time better ordering of (220) planes as a result of noise agitation. The suggested approach to characterize crystalline quality of the lattice is a general methodology that can be applied to the analysis of other three-dimensional photonic crystals.

The peculiarities of transformation of transverse structure for singular light beams propagating in a resonant medium have been analyzed theoretically. The influence of nonlinear absorption, self-focusing, and defocusing on the characteristics of optical vortices with different topological structure has been studied. The formation conditions and parameters for singular spatially localized structures have been characterized.

Temporal evolution of wavepacket tunneling in a periodic double-well torsional potential has been studied numerically. Peculiarities of wavepacket tunneling dynamics under conditions of asymmetric distortion of the periodic potential function have been analyzed.

Regular arrays of parallel nanotubes of chrysotile asbestos have been infilled with CdTe nanocrystals using capillary forces. The radiative recombination of photoexcited electron–hole pairs has been studied using photoluminescence and photoluminescence excitation techniques. The co-existence of two channels of radiative relaxation of photoexcitations generated in the nanocomposite, namely, the recombination in nanocrystals and the recombination in template defects, has been observed. The enhancement of the defect emission in infilled asbestos has been interpreted as a result of trapping the electron–hole pairs from nanocrystals. Selective inhibition of emission from nanocrystals has been observed in nanotubes co-infiltrated with semiconductor and gold nanoparticles.

Nanowires have been formed by the infiltration of CdTe nanocrystals (NCs) into nanotubes of chrysotile asbestos (Mg3Si2O5(OH)4). Photoluminescence of a regular array of these templated nanowires was studied under the excitation of the light from a xenon lamp at different wavelengths. Strong interactions of nanocrystals with structural defects of the template were observed. No dependence of the photoluminescence spectra upon polarisation of the laser beam was observed and no shift of the photoluminescence band was detected in the light polarised along and across nanowires, thus indicating the weakness of the interaction between nanocrystals in the nanotubes.

Thin opal films are prepared by crystallization in a moving meniscus, and their optical transmission spectra are recorded in polarized light and studied. It is shown that the anisotropy of light propagation in the films is unambiguously related to the photonic band structure of opal and depends on the angle of incidence, the orientation of the incidence plane with respect to the opal lattice, and the wavelength and polarization of the incident light. Azimuthal diagrams of transmitted polarized light are constructed in the range of photonic band gaps of three orders for oblique incidence of a light beam. The anisotropy is found to vary with the light wave-length independently in perpendicular polarizations. A model of the band structure of opal wherein opal is represented as an fcc lattice of close-packed spheres adequately describes the optical transmission of opal films only in the range of the first-order photonic band gap.

In the context of Si-based photonics, we report on a strategy to integrate two optical components, a 3D photonic crystal light emitter and a waveguide, in a silicon-on-insulator patterned substrate. Self-assembled colloidal photonic crystals are produced with high crystalline quality and spatial selectivity. Plane wave expansion and finite-difference time-domain have been used to find suitable configurations for positioning emitters and waveguides. The first steps toward the realisation of these configurations are presented.

Light propagation in photonic hetero-crystals, consisting of two opal films with different lattice constants, has been investigated in the realistic regime of weak scattering, when the main light flux is transported by ballistic photons. The light scattering at the photonic bandgap interface is studied in combination with transmission data. The spectra and directionality diagrams of scattered light of single- and hetero-opal films are compared. The rate of decrease of the scattering intensity as a function of the scattering angle has been used to quantify the scattering strength. The anisotropy of the interface scattering is identified by deducing the trajectories of single scattered photons from scattered light spectra. It is found that the weak scattering regime is preserved in the hetero-opal. Moreover, the diffusively scattered light leaving the double-film is mostly generated in the film, which faces the detector.

The directionality of the polarised light transmission has been studied in heterogeneous photonic crystals based on double-film opal in comparison to homogeneous crystals on single-film opals. In spite of additional scattering at the photonic bandgap interface, ballistic propagation has been preserved. Changes of the polarisation anisotropy in hetero-opal compared to homogeneous opal have been assigned to specific mode matching conditions at the photonic bandgap interface.

We report on the fabrication of high-quality opaline photonic crystals from large silica spheres (diameter of 890 nm), self-assembled in hydrophilic trenches of silicon wafers by using a novel technique coined a combination of "lifting and stirring". The achievements reported here comprise a spatial selectivity of opal crystallization without special treatment of the wafer surface, a filling of the trenches up to the top, leading to a spatially uniform film thickness, particularly an absence of cracks within the size of the trenches, and finally a good 3D order of the opal lattice even in trenches with a complex confined geometry, verified using optical measurements. The opal lattice was found to match the pattern precisely in width as well as depth, providing an important step toward applications of opals in integrated optics.

New nanocomposites based on zeolites (NaA-NaNO2, NaA-NaNO3) and opals (o-NaNO2, o-NaNO3) that contain sodium nitrite or sodium nitrate nanoparticles in cages of regular porous matrices are prepared. The nanocomposites are characterized by scanning electron microscopy, diffuse reflectance spectroscopy, and electrical measurements.

Spectra of transmitted and forward scattered light of single opal films and triple-film hetero-opals have been compared. The presence of an intermediate film in hetero-opal results in an anomalous increase of the scattered light intensity and in the change of the mainly ballistic light propagation regime to the mainly diffusive one in the frequency range of the photonic bandgap defect state.

The interaction between surface plasmon resonance of the metallodielectric photonic crystal and the Bragg resonance of the opal photonic crystal has been studied. Two types of samples were investigated, differing in the topology of the metal content, metal-dielectric photonic crystals prepared using layer-by-layer deposition coating spheres with oppositely charged polyelectrolyte and Au nanoparticles and infiltrated opaline structures with Au nanoparticles. It was found that when the“red”-shift of plasmon resonance overlaps the Bragg diffraction, the latter become almost disperionless.

Transmission, scattering and reflectance of bulk opals and thin opal films have been studied using a micro-optical set-up. Spectra of transmitted and scattered light are similar and complementary to reflectance spectrum. Long- and short-range attenuation mechanisms have been identified and related to the scattering on lattice defects.

dimensional photonic bandgap structures working in the visible have been given increasing attention in recent years encouraged by the possibility to control, modify or confine electromagnetic waves in all three dimensions, since this could have considerable impact on novel passive and active optical devices and systems. Although substantial progress has been made in the fabrication of 3D Photonic crystals by means of nano-lithography and nanotechnol- ogy, it still remains a challenge to fabricate these crystals with feature sizes of the half of the wavelength in the visible. Self-assembling of colloidal particles is an alternative method to prepare 3-dimensional photonic crystals. The aim of this article is to show how to use col- loidal crystals as templates for photonic crystals and how to monitor the changes of their optical properties due course of the modification.

Different methods of functionalisation of thin opal films are discussed, including synthesis of opals on pre-patterned substrates, post-synthesis electron beam lithography, preparation of opals with heterogeneous photonic band gap structure and integrating opals with light sources. These approaches have been tested experimentally and key technological problems have been identified.

The characteristic features of the absorption, luminescence and photoluminescence excitation spectra of InP nanocrystals crystallized in chrysotile asbestos nanotubes and CdS nanocrystals crystallized in hollow channels of a dielectric template have been explained in terms of exciton transitions in semiconductor–dielectric quantum wires. In these structures, the dielectric confinement effect leads to a considerable increase of the exciton binding energy—the Coulomb attraction between electron and hole is considerably enhanced as a result of the difference between the permittivities of the semiconductor and insulator. The kinetics of porous InP photoluminescence at high excitation by picosecond laser pulses has been explained by the slowing down of the intraband energy relaxation, collective exciton–exciton (electron) interaction and Auger recombination in nanostructures.

The steady interest in nonlinear systems of optical data processing that has been shown in the last few decades is due to the prospects of direct optical image transformation and control of the space-time structure of light fields. The first investigations in this field dating back to the 1960s were developed by generalizing the ideas and methods of traditional (static) holography as applied to the processes of recording and processing the wave fields in nonlinear media. Subsequently, a close relationship between dynamic holography and nonlinear optics was established. The works along these lines revealed the phenomenon of wave-front reversal (phase conjugation) of light beams under four-wave mixing (FWM) [1]. The upsurge of investigations on the phase-conjugation optics in the 1980s set new ways in using dynamic gratings for solving various problems of transformation of the space-time structure of light fields (phase-distortion compensation, radiation self-focusing on a target, associative holographic memory, dynamic grating lasers, etc.) [2]. At the same time, the discovery in the mid-1970s of the phenomenon of optical bistability revealed at lightbeam propagation in a nonlinear Fabry–Perot interferometer filled with sodium vapors is noteworthy [3]. The investigations along these lines made it possible to devise a transphasor (an optical analog for the transistor) and optical limiters and to develop an optical memory system. The nonlinear interferometers proved to be very convenient systems for modeling various effects of self-organization. On their basis various dynamic regimes, including regenerative intensity pulsations and the transition to optical chaos were investigated [4]. In the last decade, nonlinear systems for controlling the spatial structure of laser beams received a large development effort [5]. Methods for generating light fields of new types — stationary spatially modulated, rotating, helical, and turbulent — ones were proposed. Analysis of the interaction of two light waves of equal input intensity at their counterpropagation in a nonlinear ring cavity revealed a new regime of optical bistability in which energy transfer from the less intense light beam to the more powerful one takes place and the effect of interferometer transmission asymmetry for two light beams with a practically equal input intensity is observed [6]. This effect, named asymmetric optical bistability, was also predicted later for the case of symmetric incidence of two light beams on the input mirror of a Kerr-nonlinearity Fabry– Perot interferometer [7]. The dynamics of nonlinear-optical systems under the conditions of symmetry breaking bifurcation was investigated by an example of anisotropic lasers with a saturating absorber [8] as well as in a distributed feedback system (Bragg grating) at counterpropagation of two light beams [9].

Ordered and disordered monolayers of spheres were assembled on dielectric and metallized substrate using the Langmuir-Blodgett style technique. The coexistence of Mie and diffraction resonances was investigated. Experiments showed the weak dependence of diffraction resonances on the distance between spheres, but their gradual destruction with increasing disorder. In turn, Mie resonances appear along the increased light localization in the monolayer, but experience strong blue shift and gradual reduction of the magnitude along the increased isolation in the lattice. Calculation proved that hybridization of Mie resonances rapidly vanishes along the increase of the spacing between spheres and the hopping of excitations between spheres can be expected only in tightly packed arrays.

GaAs/AlAs and GaAs/AlGaAs quantum wells and superlattices were grown by molecularbeam epitaxy and self-organized oriented silver halide micro- and nanocrystals were embedded in crystalline alkali halide matrix. We report the results of the application of optically detected magnetic resonance (ODMR) and level anticrossing (LAC) spectroscopy for the investigations of these two classes of nanostructures. ODMR and LAC spectroscopy are shown to be very suitable for obtaining important physical parameters of low-dimensional systems and for a local diagnostics of nanostructures.