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Information × Registration Number 0213U003712, 0110U004585 , R & D reports Title Investigation of optical and nonlinear optical properties of nanostructures based on noble metals and semiconductors: development of new high sensitive techniques for studying and testing the nanostructures. popup.stage_title Head Brodyn Mykhailo Semenovych, Registration Date 27-02-2013 Organization Institute of physics NASU popup.description2 Theoretical and experimental studies of the third order nonlinearity of noble metal nanoparticles (NP) depending of their size and shape have been carried out to get to know conditions making it possible to increase the nonlinearity of metal nanostructures and to search for appropriate media. Periodic Au nanostructures with a set of two type triangle NP of ~130 nm and ~300 nm transversal sizes and ~30 nm height have been synthesized by means of "nanosphere" lithography. The technology in question makes it possible to obtain periodic nanostructures consisting of clusters of NP (3 or 5 particles in a cluster) of the same shape but different size which theoretically are perspective for increasing the third order nonlinearity. The morphology of such structures has been studied by means of APM. The shape of NP variation with the technology conditions is shown. The dynamic of the structures nonlinear optical response under excitation by laser light with 800 and 400 nm wave lengths (nonresonant conditions with respect to the surface plasmon resonance) have been studied by means of pump&probe technique. The nature of the optical nonlinear response in the nonresonant conditions analysis has shown that the main contribution is related to conducting electron heating followed by their thermalization as a result of electron-electron and electro-phonon scattering. Under 400 nm excitation the intraband transitions evidently take place. Z-scan measurements of the third order optical susceptibility give the following values: Re?(3)800nm=+1,7?10-7 esu и Re?(3)460nm=+1?10-7 esu. Theory of the optical nonlinearity for metal NP of spheroid shape dissipative and nondissipative nonlinearities connecting with the dipole oscillations of metal NP electron subsystem has been developed. An analytical expression for the third order part of the dipole moment of the surface plasmons as well as absorption of the electron gas oscillation has been obtained. Product Description popup.authors Бродин Михайло Семенович Буднік Петро Іванович Волков Владислав Іванович Воловик Микола Володимирович Ляховецький Володимир Романович Руденко Валентин Іванович Стьопкін Вівктор Іванович Томчук Петро Михайлович popup.nrat_date 2020-04-02 Close