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Registration Number

0217U002388, 0112U002607 , R & D reports

Title

Nonlinear laser spectroscopy of atoms and molecules in stationary and pulsedlaser fields.

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Head

Negriyko A.M.,

Registration Date

09-02-2017

Organization

Institute of physics NASU

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The aim of study is to obtain new scientific information about the resonant interaction of laser radia-tion with matter, particularly through experimental research by methods of laser spectroscopy of high resolution using pulsed and stationary laser highly monochromatic fields with controlled spatial and temporal parameters. The laser spectroscopy techniques, including laser-fluorescence, absorption, frequency modulation spectroscopy, laser physics methods and techniques, correlation optics, holography, laser interferometry were used in researches. We obtain the new results which are important for the physics and technology of lasers, physics of laser light interaction with matter, including: Experimental study of the spectrum of molecular iodine by method of nonlinear saturated absorption and saturated dispersion laser spectroscopy was provided. The hyperfine structure of spectral line of iodine transition in the vicinity of 640 nm was registered and identified. The 40 hyperfine components and their position were determined with accuracy of better than 100 kHz using as a frequency scale measure the spectral structure of frequency modulation resonance. The resonances of coherent population trapping of rubidium atoms that are excited by laser radiation with broadband equidistantly frequency components were investigated in detail. The diode laser with a frequency shifted feedback as a source of radiation with equidistant frequency components with controlled spectral characteristics was developed and experimentally investigated. It is established that for the creation of organic supramolecular structures as polymer matrix can be used polyurethane elastomers which have high transparency in a wide spectral range, high radiation resis-tance and the ability to dissolve organic dyes while maintaining high fluorescence quantum yield and stable monomeric form of the dye. Optimized aliphatic polyurethane compositions with cross-linked structure based on heksametylendiizotsianat, olihodietylenhlikoladipinat and trimethylolpropane as linking element were created. The revealed high compatibility of nanoparticles with the polyurethane polymer can increase photostability and lifetime of the laser active polyurethanacrylat-based media. The positive effect is due to the formation of hydrogen bonds with silica and a decrease in free volume in the polymer matrix, which reduces the likelihood of interaction between dye molecules with chemically active centers (radicals, singlet oxygen). It was shown that the polymer matrix, manufactured by polycondensation technology, significantly increases the photostability of dissolved oxazine, piromethyne, phenolene organic dyes. The influence of solvatochrome effect and polarity of polyurethane matrix on the optical properties of phototropic tiopirylo- and trycarbocianine dyes. The characteristics of neodymium laser with passive Q-switch modulators based on aliphatic polyurethane with a high dielectric constant were experimentally investigated and a positive effect of the polarity of the matrix on generation efficiency of powerful monopulses was established. The correlative approach to formation of complex laser intensity pattern on target was proposed and implemented. The parameters diffraction converters were calculated theoretically and experiments were conducted to form the complex structures in the laser field in practically real time. The multiplication of laser beams, which are based on the applications of correlation techniques to one- and two-dimensional periodic structures was studied. The experimental schemes of laser spectrometer to study methane desorption from coal samples were developed and implemented. The high sensitivity and speed of the laser methane gas analysis allow to implement the scheme for the study of thermal and laser-stimulated desorption of methane with accurately reproducibility of the dynamics of methane desorption by native coal samples . The laser interferometer based on broadband semiconductor laser for applications in nanometrology was developed. The stable operation of the device at a distance of 200-800 micrometers from the test body and the ability to record the displacement of 0.1 nm were experimentally demonstrated. The results can be used in basic research in the field of laser spectroscopy and form the basis of ap-plied research of laser wavelength reference source for metrology, highly efficient laser elements based on polymeric matrices doped with dyes, laser elements for the control of spatial distribution of energy in the laser beam.

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Бащенко Сергій Мико-лайович
Безродний Володимир Іванович
Гнатовський Олександр Володимирович
Держипольська Люд-мила Анатоліївна
Марченко Людмила Станіславівна
Мацнєв Ігор Вікторо-вич
Негрійко Анатолій Михайлович
Передерій Олександр Олегович
Потьомкіна Жанна Вячеславівна
Прядко Ігор Ігорович
Прядко Лариса Дмитрі-їван
Святенко Артем Ігоро-вич
Удовицька Олена Гри-горівна
Ходаковський Сергій Володимирович
Ясковець Анатолій Олегович

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2020-04-02