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Information × Registration Number 0217U002114, 0116U008790 , R & D reports Title Laser femtosecond filaments in isotropic and anisotropic media:fundamental and applied aspects. popup.stage_title Head Blonskyi Ivan Vasylyovych, Registration Date 19-01-2017 Organization Institute of physics NASU popup.description2 The object of study: birefringent dielectric media. Objective: The project aims to study the mechanisms of interaction of ultrashort light pulses with matter and their applications. The aim is to find common patterns of spatio-temporal and spectral transformation of high intensity optical pulses of femtosecond duration in their propagation in transparent Kerr media in filamentation regime and structural changes induced by femtosecond laser pulses in optical engineering materials. Research Methods: The measurement of spectral and spatial, luminescent, polarization and temporal properties of femtosecond laser pulses in filamented mode. In recent years, much attention was attracted to issues of interpretation the relationship between the dynamics of supercontinuum, conical emission and filamentation in isotropic media. Conical radiation associated with Cherenkov emission, plasma defocusing in the tail of the pulse, with the four-wave mixing, in which the energy of the plane pump wave is transformed into a conical Stokes and anti-Stokes waves. However, outside the field of view of researchers is the question of influence of the anisotropy of the medium on the properties of the supercontinuum and conical emission generated in filaments. This project is focused on the features of a femtosecond laser filamentation in birefringent media. Also in this project we investigated the issue of reducing the pulse duration in the solid crystalline media. Main results: The periodic filamentation of femtosecond laser pulses is found in sapphire and quartz crystals. It is found that the periodic change of pulse polarization in birefringent medium in conjunction with a difference of the photon absorption cross-sections for the linear and circular polarizations is the basic physical mechanism of filament intensity modulation. The polarization features of white supercontinuum (SC) and conical emission (CE) in birefringent media for cases of nо < nе and nо > nе have been for the first time found. It has been shown that these features are caused by time lag between o- and e-polarized pulses. The polarization of CE is determined by the polarization of the trailing edge of the whole pulse, while its leading edge determines the polarization of SC. The phenomenon of temporal self-compression of filamented femtosecond laser pulse is studied using crystalline sapphire plate as a working body. The pulse of 150 fs duration is compressed to 60 fs. Compared with previous work, in which fused silica was used, resistance to laser damage processes is significantly improved. (From 1 minute to 3 hours). Scope: modification of the properties of optoelectronics materials. Product Description popup.authors Блонський Іван Васильович Головченко Олена Миколаївна Дмитрук Андрій Миколайович Кадан Віктор Миколайович Коренюк Петро Іванович Рибак Андрій Станіславович Шинкаренко Євген Вікторович popup.nrat_date 2020-04-02 Close