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We record stimulated Raman scattering spectra in chemically-pure glycerol with the formation of two Stokes satellites with equidistant Raman frequencies ν = 2889 cm−1. To excite the scattered radiation, we employ short pulses of the second optical harmonic of a YAG:Nd3+ laser with a wavelength of 532 nm. Using the fundamental harmonic of the YAG:Nd3+ laser λ = 1064 nm, we convert the infrared Stokes component of stimulated Raman scattering into the visible range of the spectrum with the help of a nonlinear crystal of barium titanate. The large Raman shift of the Stokes components of stimulated Raman scattering makes it possible to use glycerol to convert laser radiation into different spectral ranges.

Raman spectra of tryptophan and tyrosine polycrystals have been analyzed in a wide spectral range by fiber-optic spectroscopy. The Raman spectra have been recorded with a BWS465-785H spectrometer in the spectral range of 0–2700 cm–1 using a 785-nm cw laser as an excitation source. Parameters of the Raman spectra are compared for three crystalline phase modifications of aromatic amino acids: left-handed, right-handed, and racemic phase. The presence of strong Raman satellites, the characteristics of which change depending on the type of the chiral phase state of amino acid, is found in the low-frequency Raman spectra of tryptophan and tyrosine amino acid lattices. The results obtained can be used for monitoring the chiral purity of bioactive preparations containing amino acids.

The Raman spectra of different specimens of protium and deuterium water have been compared. The spectra have been recorded using a fiber-optic technique and a compact BWS465-785H spectrometer. The spectra of spontaneous Raman scattering have been excited using a cw laser with a wavelength of 785 nm. Significant differences in the low-frequency Raman spectra from different specimens of water have been observed, which were explained by the presence of structural changes and impurities in analyzed specimens. Stimulated Raman spectra in protium and deuterium water have been measured upon excitation by picosecond laser pulses at a wavelength of 532 nm. The presence of low-frequency satellites in the spectrum of stimulated Raman scattering, indicating the structuring of water due to the formation of clusters consisting of a few molecules, has been revealed.

The spectra of multifrequency parametric stimulated Raman scattering in a barium nitrate single crystal is investigated. When this single crystal is excited by ultrashort (80 ps) YAG : Nd3+ laser pulses with a wavelength of 1064 nm, a frequency comb of eight anti-Stokes components is observed in the visible spectral range. The Raman satellites are due to the totally symmetric vibrational modes of barium nitrate single crystal. The frequencies of the corresponding Raman Stokes components in the IR range (from 1193 to 9662 nm) are calculated. The results of the study open the way to form an array of laser frequencies from the IR to green spectral range with a period of 1047 cm–1.

We have measured photoluminescence spectra of an aqueous uranyl chloride solution under excitation by various light sources: semiconductor light-emitting diodes and cw laser. The excitation wavelength lay within a resonance absorption band of uranyl chloride, which ensured photoluminescence detection at exposure times of 10–3 s using an extremely small volume of the substance (10–9 cm3). The photoluminescence spectra were measured using a small minispectrometer, which allowed us to analyze the spectra in the range 200–1000 nm.

Isofrequency dependences of the spectral intensities of inelastic scattering in LiTaO3, Pb5Ge3O11, BaTiO3, and KNbO3 crystals are registered at a fixed frequency of the spectrometer close to that of the exciting radiation. Results from soft mode analysis are presented.

A technique of probe photoluminescence and Raman spectroscopy has been developed. This technique makes it possible to detect small (10−6 to 10−8 g) amounts of uranyl compounds at short exposure times (1−10 s). The photoluminescence spectra of Na[UO2CH3(COO)3] polycrystals recorded upon excitation by short-wavelength radiation of LEDs and lasers are found to contain equidistant bands with a shift of 854 cm−1, which corresponds to the frequency of totally symmetric uranyl vibration also manifesting itself in Raman spectra.

Mesoporous photonic-crystal alumina based films are synthesized by the anodic etching of thin aluminum plates. The transmission and reflection spectra of the synthesized films in a wide spectral range including several primary band gaps are given. Some microscopic parameters of samples are calculated, and the transmission and reflection spectra are plotted for the first six band gaps alongside with photon dispersion curves.

The photoluminescence spectra of sodium uranyl acetate polycrystals are recorded under excitation by different sources (semiconductor light-emitting diodes, cw lasers, and repetitively pulsed lasers). The excitation wavelengths fall into the absorption band of this solid, which makes it possible to record photoluminescence beginning from an extremely small volume of the material (10–10 cm3) at exposures of ~10–3 s.

Secondary emission spectra of globular silica photonic crystals when their surfaces were exposed to laser pulses 250 fs long at a power density to 1 TW/cm2 have been studied. Optical harmonics and plasma emission were detected in this case. For the opal matrix containing pores filled with air, in the reflection mode, the third optical harmonic with a conversion efficiency of ∼10% arises. The highest conversion efficiency for exciting radiation with wavelengths of 1026 or 513 nm is implemented when the frequencies of the exciting radiation or the second harmonic are near the stop band edge. In globular photonic crystals filled with sodium nitrite or barium titanate ferroelectrics, the second optical harmonic is observed. The exciting radiation conversion efficiency to the second optical harmonic was a few percent and depended on the frequency of exciting radiation and photonic crystal globule diameters. It is found that the plasma emission intensity increases with the exciting radiation power density. The dependences of the intensity of the second and third optical harmonics on the pump intensity are constructed for various photonic crystal globule diameters.

The technique for recording Raman spectra in uranium compounds using a probe minispectrometer with a multielement radiation detector has been developed. A selective filter, which reflects exciting laser radiation and transmits Raman signals, has been used to suppress the exciting radiation. It is shown that the technique developed makes it possible to record Raman spectra from a small amount (~10–5 g) of sodium uranyl-acetate polycrystals in a wide spectral range for several seconds.

The characteristics of stimulated Raman scattering in benzene and carbon disulfide introduced in pores of globular photonic crystals—opal matrices formed from close-packed balls (globules) of amorphous quartz (silica)—have been experimentally studied. Stimulated Raman scattering spectra have been excited by giant pulses of the second optical harmonic (532 nm) of a YAG laser. The spectra have been recorded in the direction of mirror reflection from the (111) growth surface of a globular photonic crystal at various angles of incidence (10°–70°) of laser radiation. It has been shown that the threshold of stimulated Raman scattering decreases sharply (by more than an order of magnitude) at a certain angle of mirror reflection and additional Stokes and anti-Stokes Raman satellites appear in the spectrum. The observed sharp decrease in the threshold of stimulated Raman scattering has been explained by an increase in the spectral density of the electromagnetic field in the surface region of the photonic crystal because of the approach of the spectral position of the stopband of the photonic crystal to the exciting line (532 nm) under variation of the angle of incidence of pump radiation on the (111) surface.

This paper reports on the results of experimental investigations of the generation of the second optical harmonic localized in a thin subsurface layer of ferroelectric photonic crystals and photon traps. To excite the second optical harmonic, a KGW: Yb solid-state pulsed-periodic laser generating the radiation with a wavelength of 1026 nm in a form of pulses ∼10−13 s long with a repetition frequency of 200 kHz at the average power of 0.1–3.5 W and power density of ∼109−1012 W/cm2 in a spot less than 100 μm in diameter focused near the surface was used. Ferroelectrics, notably, barium titanate or sodium nitrite, were introduced into the pores between SiO2 nanoglobules. It is established that the maximal conversion efficiency of the exciting radiation into the second optical harmonic was several percents. The generation characteristics of the second optical harmonic near the surface of photonic crystals filled with ferroelectrics are compared with the generation of the second optical harmonic in ferroelectric photon traps of barium titanate ceramics and sodium nitrite microcrystals.

Multi-frequency stimulated Raman scattering spectra were recorded with excitation of infrared (λ0=1064 nm) emission of picosecond solid state laser. The registration of spectra was with the fiber-optic technique by minispectrometer at wide frequency region.

In this paper, the features of the Raman spectra in diamond microcrystals were investigated. The Raman spectra in microdiamonds were characterized by high intensity due to the effects of trapped radiation and total internal reflection. A characteristic line with a frequency of 1332 cm–1 and additional bands located in the overtone region of fundamental modes was registered in the observed spectra. Raman spectra in diamond-substances composites (diamond: K2Cr2O7, NaBrO3, NaNO2, HgI2, K2CrO4, PbO, KIO3, sulfur, iodine, stilbene, triglyceride sulfate, and POPOP) were detected.

We present the results of an experimental study of the spontaneous and stimulated Raman scattering (SRS) spectra and luminescence spectra of light and heavy waters. Also we investigate various samples of light water. We show the possibility of using spectral methods to detect impurities in water and determine the degree of its structuredness, which can serve as an additional criterion of the water quality. We find a fine structure in the SRS spectrum of heavy water in the low-frequency region.

The structure and optical properties of quantum-dot photonic crystals (quantytes) were studied. Such crystals have the so-called band gaps, which leads to a strong reflection of electromagnetic waves from the crystal surface. It was shown that in certain spectral regions the refractive index has a negative sign, and the group velocity of electromagnetic waves essentially decreases. The applications of quantytes as optical information recording and rewriting devices, negative refractive optical elements, selective mirrors, narrowband filters, and others were discussed.

In this paper, we present the results of the study of supernatant liquid of washed erythrocytes by the photoluminescence upon ultraviolet excitation. The spectra of intrinsic photoluminescence of an aqueous solution of “Sodium adenosine triphosphate-Vial” (Na2ATP) were compared with the spectra of supernatant liquid of erythrocytes with added Na2ATP, glucose, and without additional substances. The results of the comparison suggest that ATP emerging from washed erythrocytes into environment can be recorded in supernatant liquid.

The photoluminescence spectra of aromatic compounds in a photon trap under ultraviolet pulse-periodic excitation are recorded. It is shown that the photoluminescence spectrum shape depends on the material layer thickness in a cell, physical state of the sample, and exciting radiation characteristics: as the layer thicknesses decreases, the intensity is significantly redistributed, which is explained by the transition from spontaneous luminescence to superluminescence.

We have measured visible to near-UV reflection spectra of opal photonic crystals infiltrated with ferroelectrics: barium titanate, sodium nitrite, potassium iodate, and triglycine sulfate. An experimental procedure has been developed for the infiltration of various ferroelectrics into opal pores through laser ablation and laser implantation. Using a fiber-optic probe, we were able to analyze surface reflection spectra of photonic crystals with a 0.2-mm resolution. A deuterium lamp was used as a broadband UV source, which allowed us to observe both the first and second [111] photonic band gaps in the reflection spectrum of opal crystals.

A method for diagnosing the molecular structure and composition of aromatic bioactive preparations is developed by the example of pharmaceutical objects: analgin, citramon, aspirin, and paracetamol. The method is based on fiber-optic measurements of fluorescence spectra upon laser ultraviolet (266 nm) excitation with high (0.1 mm) spatial resolution. It is shown that the inhomogeneity of a pharmaceutical preparation containing several components is observed at a distance of a few millimeters. Difference fluorescence spectra are constructed, which allow detection of differences in preparation compositions and structures even in the case of closeness of their fluorescence spectra. The developedmethod can be used to control quality of a large class of bioactive structures luminescing under ultraviolet light.

We report the optical properties of a new type of photonic crystal: a transparent fused silica matrix containing quantum dots—nanoparticles of another material. In this study, nanoparticles consist of graphite zones several nanometers in size, stabilized by zirconia. The photonic crystal is prepared by high-temperature annealing (1200°C) of synthetic opal infiltrated with zirconia and a small amount of carbon. We demonstrate selective reflection of visible light from the surface of the quantum-dot crystal under broadband illumination. Such crystals are potentially attractive as narrow-band selective filters that would reflect the exciting light in Raman measurements and might be used to convert short-wavelength broadband radiation to quasi-monochromatic light in the visible range.

We present experimental results on the introduction (laser implantation) of ferroelectric NaNO2 into artificial opal pores upon exposure of a thin powder layer of sodium nitrite applied on the artificial opal surface to radiation of the ultraviolet excimer laser. Reflection spectra of broadband radiation from the laser-implanted sample surface are compared with the reflection spectra of pure initial opals, artificial opals impregnated with a saturated aqueous solution of sodium nitrite and evaporated from solvent, and samples in which NaNO2 was directly introduced in the form of a melt.

We present the experimental results on implantation of NaNO2 ferroelectric into pores of synthetic opal by illuminating with focused ultraviolet excimer-laser radiation of a sodium nitrite film located on the synthetic-opal surface. The reflection spectra of broadband radiation from the surface of implanted specimens are compared with the reflection spectra of initial (without any treatment) opals, synthetic opals filled with a saturated aqueous solution of sodium nitrite with subsequently evaporated solvent, and specimens with NaNO2 embedded as a melt. The possible mechanisms of shifts of reflected- and transmitted-radiation peaks are analyzed. Methods of implanting materials with high melting points into pores of 3D photonic crystals are proposed.

We have studied the optical properties of gold- and silver-infiltrated opal photonic crystals composed of close-packed SiO2 spheres ∼200 nm in diameter. The reflectivity spectra obtained are used to assess the photonic band gap of the crystals in the visible range. We present the characteristics of the emission induced in the opal photonic crystals by monochromatic and broadband light sources and calculated reflectances of the synthetic opal samples.

We have studied the optical properties of opal photonic crystals infiltrated with the M0.35Zn0.65Fe2O4 (M = Ni, Co) ferrites. The crystals consisted of amorphous SiO2 nanospheres. The visible reflectivity spectra of the crystals were used to determine parameters of their photonic band gap and their refractive index.

We analyze broadband visible reflectivity spectra of opal photonic crystals annealed in an argon atmosphere and air. Scanning electron microscopic examination has shown that the crystals consist of close-packed spheres with a mean diameter in the range 200–290 nm. Incorporation of even small amounts of carbon (≃0.5 wt %) increases the density of the opal matrix. The presence of carbon shifts the Bragg reflection peak of the opal and increases its intensity.

Results of optical properties investigations of photonic crystals, filled by ferrites, are presented. The photonic crystals consist of amorphous SiO2 spherical nanoclusters. Pores of the crystals were filled by ferrites , where . Reflectance spectra were studied in visible range. It was shown that the reflectivity of the fabricated magnetophotonic crystals increases up to 80% under magnetization.

Spontaneous Raman-scattering spectra of light in ADP and DADP crystals were obtained in four polarization schemes, the widths of some Raman lines were measured. The presence of a strong and sharp Raman line corresponding to the totally symmetric vibration of the phosphate group and a strong diffuse Raman satellite corresponding to the totally symmetric vibration of the ammonium group in the spontaneous scattering spectra of both (ADP and DADP) crystals was observed. According to the theory, such lines are preferable for the stimulated Raman scattering.

The paper is devoted to the results of investigating the spontaneous Raman scattering spectra in the lithium compounds crystals in a wide spectral range by the fibre-optic spectroscopy method. We also present the stimulated Raman scattering spectra in the lithium hydroxide and lithium deuteride crystals obtained with the use of powerful laser source. The symmetry properties of the lithium hydroxide, lithium hydroxide monohydrate and lithium deuteride crystals optical modes were analyzed by means of the irreducible representations of the point symmetry groups. We have established the selection rules in the Raman and infrared absorption spectra of LiOH, LiOHH2O and LiD crystals.

Mesoporous one-dimensional photonic crystals based on aluminum oxide have been synthesized by electrochemical etching method. Reflection spectra of the obtained mesoporous samples in a wide spectral range that covers several band gaps are presented. Microscopic parameters of photonic crystals are calculated and corresponding reflection spectra for the first six band gaps are presented.

Stimulated Raman Scattering in globular photonic crystals and globular photonic glasses at different diameters of globules (250 – 400 nm) with embedded molecular liquids is studied under excitation by nanosecond or picoseconds laser pulses. Substantial decrease of Stimulated Raman Scattering threshold was observed. Such phenomenon was explained as the result of laser radiation field increase in globular photonic structures due to photonic density of states enhancement near the edges of photonic stop bands of photonic crystals and due to Mie resonance or whispering gallery modes effect revealing in photonic glasses. Stimulated Raman Scattering threshold lowering as a result of light capture in globular photonic crystals and photonic glasses opens the way to new efficient laser sources created on the base of composite globular photonic structures. Experimental data on spectra of Stimulated Raman Scattering in light and heavy waters are presented. As sources of exciting light the powerful ultra short solid state laser pulses with 532.0 nm wavelength and giant pulses of Ruby laser (694.3 nm) have been used. Several Stokes and anti-Stokes satellites were observed. Libration modes have been excited and resulted in some additional Raman bands at low frequency region and also as combining tones.

As is known, studies of the soft x radiation of cosmic objects using proportional flow counters of large area are associated with considerable technical difficulties. At the same time, the use of reflecting x-ray optics is possible in this region of the spectrum (softer than l keV). It is advisable to examine the use of reflecting x-ray telescopes in two aspects. On the one hand, the reflecting optics makes it possible to have a comparatively large collecting area with small detector dimensions, which decreases the technical difficulties to a considerable extent and increases the signal-to-noise ratio; on the other hand, reflecting objectives open up the possibility in principle of obtaining an image analogous to that provided by telescopes in the visible region of the spectrum.

The classical instrument for the study of cosmic sources of x radiation is the photon counter equipped with a mechanical collimating system for the isolation of radiation from individual sections of the celestial sphere. Such “collimator telescopes” have been used since the very inception of x-ray astronomy in 1962 and, in particular, in the especially fruitful experiment on the Uhuru satellite [1], For a number of years, however, considerable attention has been paid to reflecting x-ray telescopes of “glancing incidence.” Such telescopes are especially promising for studies in the soft x-ray region of the spectrum of λ > 10 A (E < 1 keV). At shorter wavelengths the glancing angle of the ray must be very small (< 1°) and mirrors with a focus of several meters are required to obtain a significant effective area. Studies of sources of soft x radiation have already been conducted using reflecting telescopes mounted on rockets [2–5].