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Information × Registration Number 0213U000511, 0112U006100 , R & D reports Title Development of nonlinear- optical diagnostic methods for solar nanocomposite materials. popup.stage_title Head Poroshin Volodimir Mikolayovich, Registration Date 13-02-2013 Organization Institute of physics NASU popup.description2 Based on existing methods of investigation of nonlinear-optical response for bulk media the methods of noncontact nonlinear optical diagnostics of silicon nanostructured materials, which are based on phenomena of self-influence pulsed / continuous laser emission and generation of the optical second harmonic, have been developed. The developed methods enable to separate contributions of surface / defect states and bulk material response into the macroscopic nonlinear optical response of nanocomposite taking into account large specific surface of silicon nanowires / nanoparticles and significant manifestation of the phenomenon of light localization. The proposed methods are worked out at studies of model objects - mesaporous silicon films with different extent of surface oxidation. There is created a technique for studying the kinetics of induced light absorption in the course of propagation of femtosecond laser pulses in nanocomposite media with Kerr nonlinearity according the common scheme - "excitation-probing" for femto-picosecond time interval. There are described an original scheme to reduce the duration of the probe pulse and the method of allocation of a separate compressed pulse. A system for self-compression of a femtosecond laser pulse for use in time-resolved measurements has been made. The technique was tested at studies of induced absorption in nanostructured silicon samples obtained by isothermal annealing of films with non-stoichiometric composition of SiOx (x < 2). The laboratory technology to fabricate thin (with thickness less than 1 mm) films of amorphous-crystalline silicon nanocrystals with dimensions of a few nanometers has been developed. High-energy electron irradiation and doping by isovalent elements (Sn, Pb) are used to control the processes of nucleation and growth of nanocrystals in amorphous silicon matrix. The technology differs by the fact that nanocomposite formation occurs at 300C. This enables to use it for fabrication of film heterostructures for photoelectric conversion made on polymer substrates. Product Description popup.authors Блонський Іван Васильович Бродин Михайло Семенович Гайворонський Володимир Ярославович Головченко Олена Миколаївна Дмитрук Андрій Миколайович Кадан Віктор Миколайович Копиловський Максим Володимирович Коренюк Петро Іванович Неймаш Володимир Борисович Поварчук Василь Юрійович Порошин Володимир Миколайович Рогуцький Іван Станіславович Фролова Олена Костянтинівна popup.nrat_date 2020-04-02 Close