Search academic texts

Information × Registration Number 0120U102326, ( 0221U000079  0222U004051  ) R & D request Title Nonlinear-optical, spectral, photoelectronic and transport properties of nanostructures based on metal oxides, noble metals, semiconductors and carbon nano-objects functionalized by dyes. Head Brodyn Mykhailo S, д.ф.-м.н. Registration Date 29-04-2020 Organization Institute of Physics of National Academy of Sciences of Ukraine popup.description1 The purpose of the work is: - the searching of effective nonlinear-optical low-dimensional media with high values and small time of optical cubic response, suitable for use in modern optoelectronics. Low-dimensional structures: thin films of some metal oxides (PdO, WO3 (W2O5), CuO (Cu2O) and others) and composites of gold nanoparticles - dielectric thin layer - ometal oxide thin layer will be synthesized and investigated as possible objects for this purpose. The data from the literature suggest that high nonlinearity parameters can be expected in metal oxides (in addition, thin oxide films are relatively easy to synthesize). The optical spectra, the value and the speed of their nonlinear cubic susceptibility χ (3) by action of nanosecond and femtosecond laser radiation of such objects will be measured. The nature of nonlinearity will be explored. The results of the experiment and their analysis will allow us to determine the most effective of the considered nonlinear media. - using optical and spectroscopic methods to investigate and obtain new information on the course of exciton and electron processes in the dispersion media of quantum dots of zinc and cadmium chalcogenides and to show a strong interaction between them, which causes high efficiency of the excitation energy transfer in these structures. Prove that the excitation energy transfer mechanism can be intermediate between the exciton (Forster) hopping mechanism or the coherent exciton delocalization (Dexter). - to create photosensitive nanocomposites from quantum dots, carbon allotrop nanoparticles (fullerenes, nanotubes) with polymethine dyes (PMB) and to investigate the mechanisms of photosensitization and relaxation of electronic states of PMB molecules. On the basis of them, to create nanocomposites with carbon nanoobjects and quantum dots and, under pulsed laser excitation in the nanosecond and picosecond range, to study the life time of molecules. popup.nrat_date 2024-12-10 Close