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Information × Registration Number 0213U002300, 0111U005451 , R & D reports Title Study of propagation of extremely powerful light pulses in transparent media using laser femtosecond complex. popup.stage_title Head Blonskyy Ivan Vasylyovych, Registration Date 23-01-2013 Organization Institute of physics NASU popup.description2 Objects of research: transparent dielectric materials (sapphire, fused quartz) chalcogenide glassy semiconductors. Objective: To study the physical mechanisms of interaction of femtosecond laser radiation with transparent optoelectronic materials. Research Methods: Methods of measuring spectral-spatial properties of femtosecond laser radiation in filamented mode, Z-scanning, transmissin microscopy, autocorrelation measurements. TPA coefficient ? and the nonlinear refractive index n2 of g-As4Ge30S66 is measured using Z-scan technique. The filamented propagation mode of femtosecond laser pulses is for the first time observed in chalcogenide glasses. Spectral widening of the laser pulse and its modulation is also recorded in filament mode in g-As4Ge30S66, indicating the temporal pulse splitting. Permanent filament-induced waveguides are for the first time written in chalcogenide glasses exemplified by g-As4Ge30S66. It is shown that the self-writing process occurs in two stages. Kerr self-focusing induces optical filament at the first reversible stage. Permanent waveguide is formed at the second stage. Positive refractive index change ~ 0,5 o 10-3 is observed in the area of ~ 3 mm diameter along the axis of the waveguide, around which there is a zone of negative changes ~ 7 ?m in diameter. Self-compression and temporal separation of femtosecond laser pulse are investigated at the transition to the filament mode. The compressed pulse is for the first time separated at the filamentation in fused quartz. The output pulse duration of 63 fs is achieved at 160 fs input pulse duration. The self-compression system of femtosecond laser pulse is made for use in time-resolved "pump-probe" measurements. The results are used to improve temporal resolution of the experimental techniques for Collective Use Center "Femtosecond Laser Complex" and can be used for development of optoelectronics devices. Product Description popup.authors Блонський Іван Васильович Головченко Олена Миколаївна Зубрілін Микола Глібович Кадан Віктор Миколайович popup.nrat_date 2020-04-02 Close