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Information × Registration Number 0217U007015, 0117U002910 , R & D reports Title Development of the extreme ultraviolet interference lithography technologies for a fabrication of nanosized plasmonic structures "metallic grating-semiconductor heterostructures" and investigations of the structures as core elements of terahertz radiation sources. popup.stage_title Head Korotieiev Vadym Vyacheslavovych, Registration Date 21-12-2017 Organization Institute of Semiconductor Physics popup.description2 The work is devoted to the complex study of ultrahigh-frequency characteristics of hybrid nano-plasmonic structures such as "metal grating-semiconductor heterostructure" for their use as the core elements of generators and detectors of terahertz radiation with electric pumping and electrical control of operating frequencies. In the reporting period, the studies focused on the development of a kinetic theory of plasmon oscillations in a strong electric field and the search for parameters in which the effect of the plasmon instability occurs that is necessary for the generation of terahertz radiation. It is shown that the effect of plasmon instability arises in heterostructures based on GaAs and InAs with carrier concentrations of 1-4x1011 cm-2 when stationary fields of order 1 kV / cm are applied. The characteristic wave vectors of plasmons correspond to grating periods of 100-300 nm. Also, the nonlinear effect of detection of THz radiation by drifting two-dimensional electron gas is analyzed. The developed theory of detection was applied to the analysis of THz properties of plasmonic structures based on quantum AlGaAs / GaAs heterostructures. The influence of an optically -thick dielectric substrate and the effect of carriers heating at high drift velocities on the spectral characteristics of the transmittance / absorption coefficients and the shape of the photoresponse voltage spectrum is analyzed. It was found that in the range of applied electric fields 200 .. 400 V / cm the photoresponse voltage can reach values of tens of mV for external signals with a power density of 1 W / cm2 in the frequency range of 0.3..1 THz. The completed set of theoretical works allowed to outline the parameters of hybrid plasmonic structures and develop technological tasks for their production for future use as generators and detectors of THz radiation. According to the recommendations of the theoretical group, the basic AlGaAs / GaAs quantum heterostructures were fabricated by molecular-beam epitaxy methods. The initial characterization of these structures showed the existence of a two-dimensional conducting channel with an electron concentration of 4x1011 cm-2 and a mobility of 5000 cm2 / Vs at room temperature. Samples of basic AlGaAs / GaAs quantum heterostructures are transferred to the Ukrainian for study the high-field characteristics. Together with the German group, a technological cycle of work was developed for the deposition of a nanoplasmonic element in the form of a large-area metallic grating with a submicron periods. Product Description popup.authors Бєляєв Олександр Євгенович Вайнберг Віктор Володимирович Кочелап Вячеслав Олександрович Кухтарук Сергій Миколайович Лящук Юрій Миколайович Наумов Андрій Вадимович Порошин Володимир Миколайович Сингаївська Галина Іванівна popup.nrat_date 2020-04-02 Close