"New Journal of Physics" . . "Ku\u017Eel, Petr" . . . . . . "Sep" . "We propose an analytical description of the role of local depolarization fields in the terahertz conductivity of nanostructured samples and demonstrate this approach in a sample composed of silicon nanocrystals fabricated by electrochemical etching of silicon wafer followed by an oxidizing treatment. The post-etching treatment leads to a decrease in the average nanocrystalline Si core size which enhances luminescence in the visible range. We show that the dominating microscopic photoconductive response of photocarriers is essentially Drude-like owing to the presence of a very small amount of large nanocrystals; the macroscopic character of the response is, however, deeply modified by the depolarization fields. Smaller nanocrystals appreciably con- tribute to the terahertz conductivity only at high photoexcitation densities where the screening due to depolarization fields suppresses the response of the large particles."@en . . . "Kadlec, Christelle" . "RIV/68378271:_____/14:00439724!RIV15-GA0-68378271" . . "50506" . . . "[BF9DC3AA8836]" . . . . . "16" . "ultrafast photoconductivity; Si nanocrystals; charge carrier transport; terahertz spectroscopy"@en . . "000342050600001" . "6"^^ . . "DE - Spolkov\u00E1 republika N\u011Bmecko" . "I, P(GA13-12386S), P(GPP204/12/P235)" . "K\u016Fsov\u00E1, Kate\u0159ina" . "N\u011Bmec, Hynek" . "6"^^ . "THz photoconductivity in light-emitting surface-oxidized Si nanocrystals: the role of large particles"@en . "We propose an analytical description of the role of local depolarization fields in the terahertz conductivity of nanostructured samples and demonstrate this approach in a sample composed of silicon nanocrystals fabricated by electrochemical etching of silicon wafer followed by an oxidizing treatment. The post-etching treatment leads to a decrease in the average nanocrystalline Si core size which enhances luminescence in the visible range. We show that the dominating microscopic photoconductive response of photocarriers is essentially Drude-like owing to the presence of a very small amount of large nanocrystals; the macroscopic character of the response is, however, deeply modified by the depolarization fields. Smaller nanocrystals appreciably con- tribute to the terahertz conductivity only at high photoexcitation densities where the screening due to depolarization fields suppresses the response of the large particles." . . . "Pelant, Ivan" . . . "1367-2630" . . "RIV/68378271:_____/14:00439724" . "25"^^ . "THz photoconductivity in light-emitting surface-oxidized Si nanocrystals: the role of large particles" . "THz photoconductivity in light-emitting surface-oxidized Si nanocrystals: the role of large particles"@en . "Zajac, V\u00EDt" . "10.1088/1367-2630/16/9/093013" . . "THz photoconductivity in light-emitting surface-oxidized Si nanocrystals: the role of large particles" .